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Kelly PH, Tan Y, Yan Q, Shafquat M, Davidson A, Xu Q, Major M, Halsby K, Grajales A, Davis J, Angulo FJ, Moïsi JC, Stark JH. Borrelia burgdorferi sensu lato prevalence in Ixodes scapularis from Canada: A thirty-year summary and meta-analysis (1990-2020). Acta Trop 2024; 256:107268. [PMID: 38782109 DOI: 10.1016/j.actatropica.2024.107268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/30/2024] [Accepted: 05/21/2024] [Indexed: 05/25/2024]
Abstract
Borrelia burgdorferi sensu lato (Bb) are a complex of bacteria genospecies that can cause Lyme disease (LD) in humans after the bite of an infected Ixodes spp. vector tick. In Canada, incidence of LD is increasing in part due to the rapid geographic expansion of Ixodes scapularis across the southcentral and eastern provinces. To better understand temporal and spatial (provincial) prevalence of Bb infection of I. scapularis and how tick surveillance is utilized in Canada to assess LD risk, a literature review was conducted. Tick surveillance studies published between January 1975 to November 2023, that measured the prevalence of Bb in I. scapularis via "passive surveillance" from the public citizenry or "active surveillance" by drag or flag sampling of host-seeking ticks in Canada were included for review. Meta-analyses were conducted via random effects modeling. Forty-seven articles, yielding 26 passive and 28 active surveillance studies, met inclusion criteria. Mean durations of collection for I. scapularis were 2.1 years in active surveillance studies (1999-2020) and 5.5 years by passive surveillance studies (1990-2020). Collectively, data were extracted on 99,528 I. scapularis nymphs and adults collected between 1990-2020 across nine provinces, including Newfoundland & Labrador (33 ticks) and Alberta (208 ticks). More studies were conducted in Ontario (36) than any other province. Across nine provinces, the prevalence of Bb infection in I. scapularis collected by passive surveillance was 14.6% with the highest prevalence in Nova Scotia at 20.5% (minimum studies >1). Among host-seeking I. scapularis collected via active surveillance, Bb infection prevalence was 10.5% in nymphs, 31.9% in adults, and 23.8% across both life stages. Host-seeking I. scapularis nymphs and adults from Ontario had the highest Bb prevalence at 13.6% and 34.8%, respectively. Between 2007-2019, Bb infection prevalence in host-seeking I. scapularis was positively associated over time (p<0.001) which is concurrent with a ∼25-fold increase in the number of annually reported LD cases in Canada over the same period. The prevalence of Bb-infection in I. scapularis has rapidly increased over three decades as reported by tick surveillance studies in Canada which coincides with increasing human incidence for LD. The wide-ranging distribution and variable prevalence of Bb-infected I. scapularis ticks across provinces demonstrates the growing need for long-term standardized tick surveillance to monitor the changing trends in I. scapularis populations and best define LD risk areas in Canada.
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Affiliation(s)
- Patrick H Kelly
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., New York City, NY, USA.
| | - Ye Tan
- Medical Affairs, Evidence Generation Statistics Pfizer Inc., Cambridge, MA, USA
| | - Qi Yan
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., Collegeville, PA, USA
| | - Madiha Shafquat
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., New York City, NY, USA
| | - Alexander Davidson
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., New York City, NY, USA
| | - Qiaoyi Xu
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., New York City, NY, USA
| | - Maria Major
- Vaccines Medical Affairs Pfizer Canada ULC, Kirkland, QC, Canada
| | - Kate Halsby
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., Walton Oaks, Surrey, UK
| | - Ana Grajales
- Vaccines Medical Affairs Pfizer Canada ULC, Kirkland, QC, Canada
| | - Julie Davis
- Life Sciences, Clarivate Analytics, 3133 W. Frye Road Suite 401, Chandler, AZ, USA
| | - Frederick J Angulo
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., Collegeville, PA, USA
| | - Jennifer C Moïsi
- Medical Affairs, Vaccines and Antivirals Pfizer Inc., Paris, France
| | - James H Stark
- Medical Affairs, Vaccines and Antivirals, Pfizer Inc., Cambridge, MA, USA
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Rodríguez-Vivas RI, Flota-Burgos GJ, Torres-Castro M, Reyes-Novelo E, Sánchez-Montes S, Colunga-Salas P. Monthly fluctuation of parasitism by adult Ixodes keiransi ticks in dogs from Yucatán, Mexico. Vet Parasitol Reg Stud Reports 2024; 53:101077. [PMID: 39025538 DOI: 10.1016/j.vprsr.2024.101077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/24/2024] [Accepted: 06/30/2024] [Indexed: 07/20/2024]
Abstract
The monthly fluctuation of adult Ixodes keiransi in dogs from two cattle farms in southeastern Mexico was determined. In ranch 1 (R1), 6-7 mixed breed dogs from six months to five years of age; while in ranch 2 (R2), 7-8 mixed breed dogs from one to four years of age, were followed. All dogs were monthly inspected for tick infestation through one year. The abundance of dogs infested with ticks was estimated for each month. Tick specimens were taxonomically identified as I. keiransi using morphological features. In R1 the dogs were inspected 60 times and in R2 90 times. The overall proportion of dogs infested by ticks through the year was 75% (60/80) in R1 and 67% (67/90) in R2. The higher abundance of adult I. keiransi parasitizing dogs was from July to December with maximum peaks from September to November. In April, May and June, no ticks were observed on dogs from both ranches. Tick abundance fluctuation showed a concordant pattern with rainfall but with a delay because de maximum peak of I. keiransi abundance was almost two months after the greatest rainfall peak. It is concluded that, in some conditions, the adult I. keiransi in southeastern Mexico presents high-infested rates on dogs and a maximum abundance from September to November. The I. keiransi abundance fluctuation showed a concordant pattern with rainfall.
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Affiliation(s)
- Roger I Rodríguez-Vivas
- Campus de Ciencias Biológicas y Agropecuarias, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Carretera Mérida-Xmatkuil Km 15.5, C.P. 97100 Mérida, Yucatán, Mexico.
| | - Gabriela J Flota-Burgos
- Campus de Ciencias Biológicas y Agropecuarias, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Carretera Mérida-Xmatkuil Km 15.5, C.P. 97100 Mérida, Yucatán, Mexico
| | - Marco Torres-Castro
- Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Enrique Reyes-Novelo
- Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Mexico
| | - Sokani Sánchez-Montes
- Facultad de Ciencias Biológicas y Agropecuarias Región Poza Rica-Tuxpan, Universidad Veracruzana, Carretera Tuxpan Tampico Kilómetro 7.5, Universitaria, C.P. 92870, Tuxpan de Rodríguez Cano, Veracruz, Mexico
| | - Pablo Colunga-Salas
- Instituto de Biotecnología y Ecología Aplicada, Universidad Veracruzana, C.P. 91090 Xalapa de Enríquez, Veracruz, Mexico
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Sharma Y, Laison EK, Philippsen T, Ma J, Kong J, Ghaemi S, Liu J, Hu F, Nasri B. Models and data used to predict the abundance and distribution of Ixodes scapularis (blacklegged tick) in North America: a scoping review. LANCET REGIONAL HEALTH. AMERICAS 2024; 32:100706. [PMID: 38495312 PMCID: PMC10943480 DOI: 10.1016/j.lana.2024.100706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 03/19/2024]
Abstract
Tick-borne diseases (TBD) remain prevalent worldwide, and risk assessment of tick habitat suitability is crucial to prevent or reduce their burden. This scoping review provides a comprehensive survey of models and data used to predict I. scapularis distribution and abundance in North America. We identified 4661 relevant primary research articles published in English between January 1st, 2012, and July 18th, 2022, and selected 41 articles following full-text review. Models used data-driven and mechanistic modelling frameworks informed by diverse tick, hydroclimatic, and ecological variables. Predictions captured tick abundance (n = 14, 34.1%), distribution (n = 22, 53.6%) and both (n = 5, 12.1%). All studies used tick data, and many incorporated both hydroclimatic and ecological variables. Minimal host- and human-specific data were utilized. Biases related to data collection, protocols, and tick data quality affect completeness and representativeness of prediction models. Further research and collaboration are needed to improve prediction accuracy and develop effective strategies to reduce TBD.
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Affiliation(s)
- Yogita Sharma
- Department of Mathematics and Statistics, University of Victoria, Victoria, Canada
| | - Elda K.E. Laison
- Département de Médecine Préventive et Sociale, University of Montréal, Montréal, Canada
| | - Tanya Philippsen
- Department of Mathematics and Statistics, University of Victoria, Victoria, Canada
| | - Junling Ma
- Department of Mathematics and Statistics, University of Victoria, Victoria, Canada
| | - Jude Kong
- Department of Mathematics and Statistics, York University, Toronto, Ontario, Canada
| | - Sajjad Ghaemi
- Digital Technologies Research Center, National Research Council of Canada, Toronto, Canada
| | - Juxin Liu
- Department of Mathematics and Statistics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - François Hu
- Department of Mathematics and Statistics, University of Montréal, Montréal, Canada
| | - Bouchra Nasri
- Département de Médecine Préventive et Sociale, University of Montréal, Montréal, Canada
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Yang H, Gould CA, Jones R, St Juliana A, Sarofim M, Rissing M, Hahn MB. By-degree Health and Economic Impacts of Lyme Disease, Eastern and Midwestern United States. ECOHEALTH 2024; 21:56-70. [PMID: 38478199 PMCID: PMC11127817 DOI: 10.1007/s10393-024-01676-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 01/20/2024] [Indexed: 05/26/2024]
Abstract
Lyme disease (LD) is the most common vector-borne disease in the United States (U.S.). This paper assesses how climate change may influence LD incidence in the eastern and upper Midwestern U.S. and the associated economic burden. We estimated future Ixodes scapularis habitat suitability and LD incidence with a by-degree approach using variables from an ensemble of multiple climate models. We then applied estimates for present-day and projected habitat suitability for I. scapularis, present-day presence of Borrelia burgdorferi, and projected climatological variables to model reported LD incidence at the county level among adults, children, and the total population. Finally, we applied an estimate of healthcare expenses to project economic impacts. We show an overall increase in LD cases with regional variation. We estimate an increase in incidence in New England and the upper Midwestern U.S. and a concurrent decrease in incidence in Virginia and North Carolina. At 3°C of national warming from the 1986-2015 baseline climate, we project approximately 55,000 LD cases, a 38-percent increase from present-day estimates. At 6°C of warming, our most extreme scenario, we project approximately 92,000 LD cases in the region, an increase of 145 percent relative to current levels. Annual LD-related healthcare expenses at 3°C of warming are estimated to be $236 million (2021 dollars), approximately 38 percent greater than present-day. These results may inform decision-makers tasked with addressing climate risks, the public, and healthcare professionals preparing for treatment and prevention of LD.
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Affiliation(s)
- Haisheng Yang
- Abt Associates, 6130 Executive Boulevard, Rockville, MD, 2085, USA
| | - Caitlin A Gould
- Climate Change Division, Climate Science and Imapcts Branch, U.S. Environmental Protection Agency, 1200 Pennsylvania Ave NW, 4226-G South, Washington, DC, 20460, USA.
| | - Russ Jones
- Abt Associates, 6130 Executive Boulevard, Rockville, MD, 2085, USA
| | | | - Marcus Sarofim
- Climate Change Division, Climate Science and Imapcts Branch, U.S. Environmental Protection Agency, 1200 Pennsylvania Ave NW, 4226-G South, Washington, DC, 20460, USA
| | - Matt Rissing
- Abt Associates, 6130 Executive Boulevard, Rockville, MD, 2085, USA
| | - Micah B Hahn
- Institute for Circumpolar Health Studies, University of Alaska-Anchorage, 3211 Providence Drive, Anchorage, AK, 99508, USA
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Stokowski M, Allen D. IxPopDyMod: an R package to write, run, and analyze tick population and infection dynamics models. Parasit Vectors 2024; 17:90. [PMID: 38409067 PMCID: PMC10898031 DOI: 10.1186/s13071-024-06171-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 01/29/2024] [Indexed: 02/28/2024] Open
Abstract
Given the increasing prevalence of tick-borne diseases, such as Lyme disease, modeling the population and infection dynamics of tick vectors is an important public health tool. These models have applications for testing the effects of control methods or climate change on tick populations. There is an established history of tick population models, but code for them is rarely shared, especially not in a convenient format for others to modify and use. We present an R package, called IxPopDyMod, intended to function as a flexible and consistent framework for reproducible Ixodidae (hard-bodied ticks) population dynamics models. Here we focus on two key parts of the package: a function to create valid model configurations and a function to run a configured model and return the daily population over time. We provide three examples in appendices: one reproducing an existing Ixodes scapularis population model, one providing a novel Dermacentor albipictus model, and one showing Borrelia burgdorferi infection in ticks. Together these examples show the flexibility of the package to model scenarios of interest to tick researches.
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Affiliation(s)
- Myles Stokowski
- Department of Biology, Middlebury College, Middlebury, 05753, VT, USA
| | - David Allen
- Department of Biology, Middlebury College, Middlebury, 05753, VT, USA.
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Ogden NH, Dumas A, Gachon P, Rafferty E. Estimating the Incidence and Economic Cost of Lyme Disease Cases in Canada in the 21st Century with Projected Climate Change. ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:27005. [PMID: 38349724 PMCID: PMC10863724 DOI: 10.1289/ehp13759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 01/11/2024] [Accepted: 01/16/2024] [Indexed: 02/15/2024]
Abstract
BACKGROUND Lyme disease (LD) is emerging in Canada owing to the range expansion of the tick vector Ixodes scapularis (I. scapularis). OBJECTIVES Our objective was to estimate future LD incidence in Canada, and economic costs, for the 21st century with projected climate change. METHODS Future regions of climatic suitability for I. scapularis were projected from temperature output of the North American Coordinated Regional Climate Downscaling Experiment regional climate model ensemble using greenhouse gas Representative Concentration Pathways (RCPs) 4.5 and 8.5. Once regions became climatically suitable for ticks, an algorithm derived from tick and LD case surveillance data projected subsequent increasing LD incidence. Three scenarios (optimistic, intermediate, and pessimistic) for maximum incidence at endemicity were selected based on LD surveillance, and underreporting estimates, from the United States. Health care and productivity cost estimates of LD cases were obtained from the literature. RESULTS Projected annual LD cases for Canada ranged from 120,000 to > 500,000 by 2050. Variation in incidence was mostly due to the maximum incidence at endemicity selected, with minor contributions from variations among climate models and RCPs. Projected annual costs were substantial, ranging from CA $ 0.5 billion to $ 2.0 billion a year by 2050. There was little difference in projected incidence and economic cost between RCPs, and from 2050 to 2100, because projected climate up to 2050 is similar for RCP4.5 and RCP8.5 (mitigation of greenhouse gas emissions captured in RCP4.5 does not impact climate before the 2050s) and by 2050 the most densely populated areas of the study region are projected to be climatically suitable for ticks. CONCLUSIONS Future incidence and economic costs of LD in Canada are likely to be substantial, but uncertainties remain. Because densely populated areas of Canada are projected to become endemic under conservative climate change scenarios, mitigation of greenhouse gas emissions is unlikely to provide substantial health co-benefits for LD. https://doi.org/10.1289/EHP13759.
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Affiliation(s)
- Nicholas H. Ogden
- Public Health Risk Sciences Division, Scientific Operations and Response, National Microbiology Laboratory, Public Health Agency of Canada, St-Hyacinthe, Quebec, Canada
- Groupe de recherche en épidémiologie des zoonoses et santé publique, Université de Montréal, St-Hyacinthe, Quebec, Canada
- Centre de recherche en santé publique, Université de Montréal, Montréal, Québec, Canada
| | - Ariane Dumas
- Public Health Risk Sciences Division, Scientific Operations and Response, National Microbiology Laboratory, Public Health Agency of Canada, St-Hyacinthe, Quebec, Canada
| | - Philippe Gachon
- Étude et Simulation du Climat à l’Échelle Régionale centre, Université du Québec à Montréal, Montréal, Québec, Canada
- Department of Geography, Université du Québec à Montréal, Montréal, Québec, Canada
| | - Ellen Rafferty
- Institute of Health Economics, Edmonton, Alberta, Canada
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Eisen RJ, Eisen L. Evaluation of the association between climate warming and the spread and proliferation of Ixodes scapularis in northern states in the Eastern United States. Ticks Tick Borne Dis 2024; 15:102286. [PMID: 38016209 PMCID: PMC10884982 DOI: 10.1016/j.ttbdis.2023.102286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 11/30/2023]
Abstract
Ixodes scapularis (the blacklegged tick) is widely distributed in forested areas across the eastern United States. The public health impact of I. scapularis is greatest in the north, where nymphal stage ticks commonly bite humans and serve as primary vectors for multiple human pathogens. There were dramatic increases in the tick's distribution and abundance over the last half-century in the northern part of the eastern US, and climate warming is commonly mentioned as a primary driver for these changes. In this review, we summarize the evidence for the observed spread and proliferation of I. scapularis being driven by climate warming. Although laboratory and small-scale field studies have provided insights into how temperature and humidity impact survival and reproduction of I. scapularis, using these associations to predict broad-scale distribution and abundance patterns is more challenging. Numerous efforts have been undertaken to model the distribution and abundance of I. scapularis at state, regional, and global scales based on climate and landscape variables, but outcomes have been ambiguous. Across the models, the functional relationships between seasonal or annual measures of heat, cold, precipitation, or humidity and tick presence or abundance were inconsistent. The contribution of climate relative to landscape variables was poorly defined. Over the last half-century, climate warming occurred in parallel with spread and population increase of the white-tailed deer, the most important reproductive host for I. scapularis adults, in the northern part of the eastern US. There is strong evidence for white-tailed deer playing a key role to facilitate spread and proliferation of I. scapularis in the US over the last century. However, due to a lack of spatially and temporally congruent data, climate, landscape, and host variables are rarely included in the same models, thus limiting the ability to evaluate their relative contributions or interactions in defining the geographic range and abundance patterns of ticks. We conclude that the role of climate change as a key driver for geographic expansion and population increase of I. scapularis in the northern part of the eastern US over the last half-century remains uncertain.
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Affiliation(s)
- Rebecca J Eisen
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521, United States.
| | - Lars Eisen
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521, United States
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Pandipati S, Leong M, Basu R, Abel D, Hayer S, Conry J. Climate change: Overview of risks to pregnant persons and their offspring. Semin Perinatol 2023; 47:151836. [PMID: 37863676 DOI: 10.1016/j.semperi.2023.151836] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2023]
Abstract
Climate change is one of the greatest challenges confronting humanity. Pregnant persons, their unborn children, and offspring are particularly vulnerable, as evidenced by adverse perinatal outcomes and increased rates of childhood illnesses. Environmental inequities compound the problem of maternal health inequities, and have given rise to the environmental justice movement. The International Federation of Gynecology and Obstetrics and other major medical societies have worked to heighten awareness and address the deleterious health effects of climate change and toxic environmental exposures. As part of routine prenatal, neonatal, and pediatric care, neonatal-perinatal care providers should incorporate discussions with their patients and families on potential harms and also identify actions to mitigate climate change effects on their health. This article provides clinicians with an overview of how climate change affects their patients, practical guidance in caring for them, and a frame setting of the articles to follow. Clinicians have a critical role to play, and the time to act is now.
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Affiliation(s)
- Santosh Pandipati
- Maternal-Fetal Medicine, Obstetrix of San Jose, e-Lōvu Health, United States.
| | - Melanie Leong
- Attending Neonatologist, Neonatal ECMO Services, The Regional Neonatal Center of Maria Fareri Children's Hospital at Westchester Medical Center, New York Medical College, United States; Assistant Professor of Pediatrics, New York Medical College, United States
| | - Rupa Basu
- Air and Climate Epidemiology Section, Office of Environmental Health Hazard Assessment, California EPA, United States
| | - David Abel
- Maternal-Fetal Medicine, Oregon Health Sciences University, United States
| | - Sarena Hayer
- Obstetrics & Gynecology, Oregon Health Sciences University, United States
| | - Jeanne Conry
- International Federation of Gynecology and Obstetrics, United States
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Fellin E, Varin M, Millien V. Risky business: human-related data is lacking from Lyme disease risk models. Front Public Health 2023; 11:1113024. [PMID: 38026346 PMCID: PMC10662633 DOI: 10.3389/fpubh.2023.1113024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
Used as a communicative tool for risk management, risk maps provide a service to the public, conveying information that can raise risk awareness and encourage mitigation. Several studies have utilized risk maps to determine risks associated with the distribution of Borrelia burgdorferi, the causal agent of Lyme disease in North America and Europe, as this zoonotic disease can lead to severe symptoms. This literature review focused on the use of risk maps to model distributions of B. burgdorferi and its vector, the blacklegged tick (Ixodes scapularis), in North America to compare variables used to predict these spatial models. Data were compiled from the existing literature to determine which ecological, environmental, and anthropic (i.e., human focused) variables past research has considered influential to the risk level for Lyme disease. The frequency of these variables was examined and analyzed via a non-metric multidimensional scaling analysis to compare different map elements that may categorize the risk models performed. Environmental variables were found to be the most frequently used in risk spatial models, particularly temperature. It was found that there was a significantly dissimilar distribution of variables used within map elements across studies: Map Type, Map Distributions, and Map Scale. Within these map elements, few anthropic variables were considered, particularly in studies that modeled future risk, despite the objective of these models directly or indirectly focusing on public health intervention. Without including human-related factors considering these variables within risk map models, it is difficult to determine how reliable these risk maps truly are. Future researchers may be persuaded to improve disease risk models by taking this into consideration.
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Affiliation(s)
- Erica Fellin
- Department of Biology, McGill University, Montréal, QC, Canada
- Redpath Museum, McGill University, Montréal, QC, Canada
| | - Mathieu Varin
- Centre d'Enseignement et de Recherche en Foresterie (CERFO), Québec City, QC, Canada
| | - Virginie Millien
- Department of Biology, McGill University, Montréal, QC, Canada
- Redpath Museum, McGill University, Montréal, QC, Canada
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Millien V, Leo SST, Turney S, Gonzalez A. It's about time: small mammal communities and Lyme disease emergence. Sci Rep 2023; 13:14513. [PMID: 37667029 PMCID: PMC10477272 DOI: 10.1038/s41598-023-41901-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 08/31/2023] [Indexed: 09/06/2023] Open
Abstract
Theory predicts that biodiversity changes due to climate warming can mediate the rate of disease emergence. The mechanisms linking biodiversity-disease relationships have been described both theoretically and empirically but remain poorly understood. We investigated the relations between host diversity and abundance and Lyme disease risk in southern Quebec, a region where Lyme disease is rapidly emerging. We found that both the abundance of small mammal hosts and the relative abundance of the tick's natural host, the white-footed mouse (Peromyscus leucopus), influenced measures of disease risk in tick vectors (Borrelia burgdorferi infection abundance and prevalence in tick vectors). Our results suggest that the increase in Lyme disease risk is modulated by regional processes involving the abundance and composition of small mammal assemblages. However, the nature and strength of these relationships was dependent both on time and geographic area. The strong effect of P. leucopus abundance on disease risk we report here is of significant concern, as this competent host is predicted to increase in abundance and occurrence in the region, with the northern shift in the range of North American species under climate warming.
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Affiliation(s)
- V Millien
- Redpath Museum, McGill University, Montréal, QC, H3A 0C4, Canada.
- Department of Biology, McGill University, Montréal, QC, H3A 1B1, Canada.
| | - S S T Leo
- Redpath Museum, McGill University, Montréal, QC, H3A 0C4, Canada
- Department of Biology, McGill University, Montréal, QC, H3A 1B1, Canada
| | - S Turney
- Redpath Museum, McGill University, Montréal, QC, H3A 0C4, Canada
- Department of Biology, McGill University, Montréal, QC, H3A 1B1, Canada
| | - A Gonzalez
- Department of Biology, McGill University, Montréal, QC, H3A 1B1, Canada
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Krichel L, Kirk D, Pencer C, Hönig M, Wadhawan K, Krkošek M. Short-term temperature fluctuations increase disease in a Daphnia-parasite infectious disease system. PLoS Biol 2023; 21:e3002260. [PMID: 37683040 PMCID: PMC10491407 DOI: 10.1371/journal.pbio.3002260] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 07/18/2023] [Indexed: 09/10/2023] Open
Abstract
Climate change has profound effects on infectious disease dynamics, yet the impacts of increased short-term temperature fluctuations on disease spread remain poorly understood. We empirically tested the theoretical prediction that short-term thermal fluctuations suppress endemic infection prevalence at the pathogen's thermal optimum. This prediction follows from a mechanistic disease transmission model analyzed using stochastic simulations of the model parameterized with thermal performance curves (TPCs) from metabolic scaling theory and using nonlinear averaging, which predicts ecological outcomes consistent with Jensen's inequality (i.e., reduced performance around concave-down portions of a thermal response curve). Experimental observations of replicated epidemics of the microparasite Ordospora colligata in Daphnia magna populations indicate that temperature variability had the opposite effect of our theoretical predictions and instead increase endemic infection prevalence. This positive effect of temperature variability is qualitatively consistent with a published hypothesis that parasites may acclimate more rapidly to fluctuating temperatures than their hosts; however, incorporating hypothetical effects of delayed host acclimation into the mechanistic transmission model did not fully account for the observed pattern. The experimental data indicate that shifts in the distribution of infection burden underlie the positive effect of temperature fluctuations on endemic prevalence. The increase in disease risk associated with climate fluctuations may therefore result from disease processes interacting across scales, particularly within-host dynamics, that are not captured by combining standard transmission models with metabolic scaling theory.
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Affiliation(s)
- Leila Krichel
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Devin Kirk
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Clara Pencer
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Madison Hönig
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
- Department of Anthropology, Washington State University, Pullman, Washington, United States of America
| | - Kiran Wadhawan
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
- School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Martin Krkošek
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
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Tardy O, Acheson ES, Bouchard C, Chamberland É, Fortin A, Ogden NH, Leighton PA. Mechanistic movement models to predict geographic range expansions of ticks and tick-borne pathogens: Case studies with Ixodes scapularis and Amblyomma americanum in eastern North America. Ticks Tick Borne Dis 2023; 14:102161. [PMID: 36996508 DOI: 10.1016/j.ttbdis.2023.102161] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/30/2023]
Abstract
The geographic range of the blacklegged tick, Ixodes scapularis, is expanding northward from the United States into southern Canada, and studies suggest that the lone star tick, Amblyomma americanum, will follow suit. These tick species are vectors for many zoonotic pathogens, and their northward range expansion presents a serious threat to public health. Climate change (particularly increasing temperature) has been identified as an important driver permitting northward range expansion of blacklegged ticks, but the impacts of host movement, which is essential to tick dispersal into new climatically suitable regions, have received limited investigation. Here, a mechanistic movement model was applied to landscapes of eastern North America to explore 1) relationships between multiple ecological drivers and the speed of the northward invasion of blacklegged ticks infected with the causative agent of Lyme disease, Borrelia burgdorferi sensu stricto, and 2) its capacity to simulate the northward range expansion of infected blacklegged ticks and uninfected lone star ticks under theoretical scenarios of increasing temperature. Our results suggest that the attraction of migratory birds (long-distance tick dispersal hosts) to resource-rich areas during their spring migration and the mate-finding Allee effect in tick population dynamics are key drivers for the spread of infected blacklegged ticks. The modeled increases in temperature extended the climatically suitable areas of Canada for infected blacklegged ticks and uninfected lone star ticks towards higher latitudes by up to 31% and 1%, respectively, and with an average predicted speed of the range expansion reaching 61 km/year and 23 km/year, respectively. Differences in the projected spatial distribution patterns of these tick species were due to differences in climate envelopes of tick populations, as well as the availability and attractiveness of suitable habitats for migratory birds. Our results indicate that the northward invasion process of lone star ticks is primarily driven by local dispersal of resident terrestrial hosts, whereas that of blacklegged ticks is governed by long-distance migratory bird dispersal. The results also suggest that mechanistic movement models provide a powerful approach for predicting tick-borne disease risk patterns under complex scenarios of climate, socioeconomic and land use/land cover changes.
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13
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Wilson C, Gasmi S, Bourgeois AC, Badcock J, Carr J, Chahil N, Coatsworth H, Dibernardo A, Goundar P, Leighton P, Lee MK, Morshed M, Ripoche M, Savage J. Surveillance for Ixodes scapularis and Ixodes pacificus ticks and their associated pathogens in Canada, 2020. CANADA COMMUNICABLE DISEASE REPORT = RELEVE DES MALADIES TRANSMISSIBLES AU CANADA 2023; 49:288-298. [PMID: 38444700 PMCID: PMC10914093 DOI: 10.14745/ccdr.v49i06a06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Background Ixodes scapularis and Ixodes pacificus ticks are the principal vectors of the agent of Lyme disease and several other tick-borne diseases in Canada. Tick surveillance data can be used to identify local tick-borne disease risk areas and direct public health interventions. The objective of this article is to describe the seasonal and spatial characteristics of the main Lyme disease vectors in Canada, and the tick-borne pathogens they carry, using passive and active surveillance data from 2020. Methods Passive and active surveillance data were compiled from the National Microbiology Laboratory Branch (Public Health Agency of Canada), provincial and local public health authorities, and eTick (an online, image-based platform). Seasonal and spatial analyses of ticks and their associated pathogens are presented, including infection prevalence estimates. Results In passive surveillance, I. scapularis (n=7,534) were submitted from all provinces except Manitoba and British Columbia, while I. pacificus (n=718) were submitted only from British Columbia. No ticks were submitted from the Territories. The seasonal distribution of I. scapularis submissions was bimodal, but unimodal for I. pacificus. Four tick-borne pathogens were identified in I. scapularis (Borrelia burgdorferi, Anaplasma phagocytophilum, Babesia microti and Borrelia miyamotoi) and one in I. pacificus (B. miyamotoi). In active surveillance, I. scapularis (n=688) were collected in Ontario, Québec and New Brunswick. Five tick-borne pathogens were identified: B. burgdorferi, A. phagocytophilum, B. microti, B. miyamotoi and Powassan virus. Conclusion This article provides a snapshot of the distribution of I. scapularis and I. pacificus and their associated human pathogens in Canada in 2020, which can help assess the risk of exposure to tick-borne pathogens in different provinces.
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Affiliation(s)
- Christy Wilson
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
| | - Salima Gasmi
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Saint-Hyacinthe, QC
| | - Annie-Claude Bourgeois
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
| | - Jacqueline Badcock
- Public Health New Brunswick, New Brunswick Department of Health, Fredericton, NB
| | - Justin Carr
- New Brunswick Provincial Veterinary Laboratory, Department of Agriculture, Aquaculture and Fisheries, Fredericton, NB
| | - Navdeep Chahil
- BCCDC Public Health Laboratory, BC Centre for Disease Control, Vancouver, BC
| | - Heather Coatsworth
- National Microbiology Laboratory Branch, Public Health Agency of Canada, Winnipeg, MB
| | - Antonia Dibernardo
- National Microbiology Laboratory Branch, Public Health Agency of Canada, Winnipeg, MB
| | | | - Patrick Leighton
- Epidemiology of Zoonoses and Public Health Research Group (GREZOSP), Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, QC
| | - Min-Kuang Lee
- BCCDC Public Health Laboratory, BC Centre for Disease Control, Vancouver, BC
| | - Muhammad Morshed
- BCCDC Public Health Laboratory, BC Centre for Disease Control, Vancouver, BC
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC
| | - Marion Ripoche
- Institut national de santé publique du Québec, Montréal, QC
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14
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Sack A, Naumova EN, Price LL, Xu G, Rich SM. Passive Surveillance of Human-Biting Ixodes scapularis Ticks in Massachusetts from 2015-2019. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:4306. [PMID: 36901316 PMCID: PMC10002092 DOI: 10.3390/ijerph20054306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/24/2023] [Accepted: 02/26/2023] [Indexed: 06/18/2023]
Abstract
This study aimed to analyze human-biting Ixodes scapularis ticks submitted to TickReport tick testing service from 2015-2019 in Massachusetts to (1) examine possible patterns of pathogen-positive adult and nymphal ticks over time and (2) explore how socioeconomic factors can influence tick submissions. A passive surveillance data set of ticks and tick-borne pathogens was conducted over 5 years (2015-2019) in Massachusetts. The percentages of four tick-borne pathogens: Borrelia burgdorferi, Anaplasma phagocytophilum, Babesia microti, and Borrelia miyamotoi were determined by Massachusetts county and by month and year. Regression models were used to examine the association between zip-code-level socioeconomic factors and submissions. A total of 13,598 I. scapularis ticks were submitted to TickReport from Massachusetts residents. The infection rate of B. burgdorferi, A. phagocytophilum, and B. microti was 39%, 8%, and 7% in adult ticks; 23%, 6%, and 5% in nymphal ticks, respectively. A relatively higher level of education was associated with high tick submission. Passive surveillance of human-biting ticks and associated pathogens is important for monitoring tick-borne diseases, detecting areas with potentially high risks, and providing public information. Socioeconomic factors should be considered to produce more generalizable passive surveillance data and to target potentially underserved areas.
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Affiliation(s)
- Alexandra Sack
- Clinical and Translational Science Graduate Program, Tufts University Graduate School of Biomedical Sciences, Boston, MA 02111, USA
- Department of Biological Sciences, Eck Institute of Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Elena N. Naumova
- Division of Nutrition Epidemiology and Data Science, Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA 02111, USA
| | - Lori Lyn Price
- Tufts Institute of Clinical and Translational Science, Tufts University, Boston, MA 02111, USA
- Institute of Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA 02111, USA
| | - Guang Xu
- Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | - Stephen M. Rich
- Laboratory of Medical Zoology, Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
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15
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Kopsco HL, Gronemeyer P, Mateus-Pinilla N, Smith RL. Current and Future Habitat Suitability Models for Four Ticks of Medical Concern in Illinois, USA. INSECTS 2023; 14:213. [PMID: 36975898 PMCID: PMC10059838 DOI: 10.3390/insects14030213] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 02/11/2023] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
The greater U.S. Midwest is on the leading edge of tick and tick-borne disease (TBD) expansion, with tick and TBD encroachment into Illinois occurring from both the northern and the southern regions. To assess the historical and future habitat suitability of four ticks of medical concern within the state, we fit individual and mean-weighted ensemble species distribution models for Ixodes scapularis, Amblyomma americanum, Dermacentor variabilis, and a newly invading species, Amblyomma maculatum using a variety of landscape and mean climate variables for the periods of 1970-2000, 2041-2060, and 2061-2080. Ensemble model projections for the historical climate were consistent with known distributions of each species but predicted the habitat suitability of A. maculatum to be much greater throughout Illinois than what known distributions demonstrate. The presence of forests and wetlands were the most important landcover classes predicting the occurrence of all tick species. As the climate warmed, the expected distribution of all species became strongly responsive to precipitation and temperature variables, particularly precipitation of the warmest quarter and mean diurnal range, as well as proximity to forest cover and water sources. The suitable habitat for I. scapularis, A. americanum, and A. maculatum was predicted to significantly narrow in the 2050 climate scenario and then increase more broadly statewide in the 2070 scenario but at reduced likelihoods. Predicting where ticks may invade and concentrate as the climate changes will be important to anticipate, prevent, and treat TBD in Illinois.
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Affiliation(s)
- Heather L. Kopsco
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
| | - Peg Gronemeyer
- Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
| | - Nohra Mateus-Pinilla
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
- Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
| | - Rebecca L. Smith
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
- Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
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16
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Tiffin HS, Rajotte EG, Sakamoto JM, Machtinger ET. Tick Control in a Connected World: Challenges, Solutions, and Public Policy from a United States Border Perspective. Trop Med Infect Dis 2022; 7:388. [PMID: 36422939 PMCID: PMC9695313 DOI: 10.3390/tropicalmed7110388] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/07/2022] [Accepted: 11/17/2022] [Indexed: 07/30/2023] Open
Abstract
Ticks are able to transmit the highest number of pathogen species of any blood-feeding arthropod and represent a growing threat to public health and agricultural systems worldwide. While there are numerous and varied causes and effects of changes to tick-borne disease (re)emergence, three primary challenges to tick control were identified in this review from a U.S. borders perspective. (1) Climate change is implicated in current and future alterations to geographic ranges and population densities of tick species, pathogens they can transmit, and their host and reservoir species, as highlighted by Ixodes scapularis and its expansion across southern Canada. (2) Modern technological advances have created an increasingly interconnected world, contributing to an increase in invasive tick species introductions through the increased speed and frequency of trade and travel. The introduction of the invasive Haemaphysalis longicornis in the eastern U.S. exemplifies the challenges with control in a highly interconnected world. (3) Lastly, while not a new challenge, differences in disease surveillance, control, and management strategies in bordering countries remains a critical challenge in managing ticks and tick-borne diseases. International inter-agency collaborations along the U.S.-Mexico border have been critical in control and mitigation of cattle fever ticks (Rhipicephalus spp.) and highlight the need for continued collaboration and research into integrated tick management strategies. These case studies were used to identify challenges and opportunities for tick control and mitigation efforts through a One Health framework.
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17
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Couret J, Schofield S, Narasimhan S. The environment, the tick, and the pathogen - It is an ensemble. Front Cell Infect Microbiol 2022; 12:1049646. [PMID: 36405964 PMCID: PMC9666722 DOI: 10.3389/fcimb.2022.1049646] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 10/17/2022] [Indexed: 03/22/2024] Open
Abstract
Ixodes scapularis is one of the predominant vectors of Borrelia burgdorferi, the agent of Lyme disease in the USA. The geographic distribution of I. scapularis, endemic to the northeastern and northcentral USA, is expanding as far south as Georgia and Texas, and northwards into Canada and poses an impending public health problem. The prevalence and spread of tick-borne diseases are influenced by the interplay of multiple factors including microbiological, ecological, and environmental. Molecular studies have focused on interactions between the tick-host and pathogen/s that determine the success of pathogen acquisition by the tick and transmission to the mammalian host. In this review we draw attention to additional critical environmental factors that impact tick biology and tick-pathogen interactions. With a focus on B. burgdorferi we highlight the interplay of abiotic factors such as temperature and humidity as well as biotic factors such as environmental microbiota that ticks are exposed to during their on- and off-host phases on tick, and infection prevalence. A molecular understanding of this ensemble of interactions will be essential to gain new insights into the biology of tick-pathogen interactions and to develop new approaches to control ticks and tick transmission of B. burgdorferi, the agent of Lyme disease.
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Affiliation(s)
- Jannelle Couret
- Department of Biological Sciences, College of Environment and Life Sciences, University of Rhode Island, Kingston, RI, United States
| | - Samantha Schofield
- Department of Biological Sciences, College of Environment and Life Sciences, University of Rhode Island, Kingston, RI, United States
| | - Sukanya Narasimhan
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
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18
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Backus LH, Pascoe EL, Foley J. Will new ticks invade North America? How to identify future invaders. Trends Parasitol 2022; 38:805-814. [PMID: 35820944 DOI: 10.1016/j.pt.2022.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 06/17/2022] [Accepted: 06/19/2022] [Indexed: 11/19/2022]
Abstract
Invasive tick species and the pathogens they transmit pose increasing threats to human and animal health around the world. Little attention has been paid to the characteristics enabling tick species to invade. Here we analyze examples of tick invasion events in North America to identify factors that facilitated the invasion. Commonalities among invasive ticks are that they thrive in anthropogenically modified habitats, feed on either domestic animals or wildlife occurring in high density, and can survive across a broad range of climatic conditions. Invasive tick species varied widely in life history and reproductive habits, suggesting that invasion occurs when multiple characteristics converge. The combination of potential characteristics leading to invasion, however, improves our ability to predict future invaders and inform surveillance.
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Affiliation(s)
- Laura H Backus
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Emily L Pascoe
- Laboratory of Entomology, Wageningen University & Research, 6708, PB, Wageningen, The Netherlands
| | - Janet Foley
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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19
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The effect of climate variability in the efficacy of the entomopathogenic fungus Metarhizium acridum against the desert locust Schistocerca gregaria. Sci Rep 2022; 12:7535. [PMID: 35534636 PMCID: PMC9085851 DOI: 10.1038/s41598-022-11424-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 04/21/2022] [Indexed: 11/08/2022] Open
Abstract
Despite substantial efforts to control locusts they remain periodically a major burden in Africa, causing severe yield loss and hence loss of food and income. Distribution maps indicating the value of the basic reproduction number R0 was used to identify areas where an insect pest can be controlled by a natural enemy. A dynamic process-based mathematical model integrating essential features of a natural enemy and its interaction with the pest is used to generate R0 risk maps for insect pest outbreaks, using desert locust and the entomopathogenic fungus Metarhizium acridum (Synn. Metarhizium anisoliae var. acridum) as a case study. This approach provides a tool for evaluating the impact of climatic variables such as temperature and relative humidity and mapping spatial variability on the efficacy of M. acridum as a biocontrol agent against desert locust invasion in Africa. Applications of M. acridum against desert locust in a few selected African countries including Morocco, Kenya, Mali, and Mauritania through monthly spatial projection of R0 maps for the prevailing climatic condition are illustrated. By combining mathematical modeling with a geographic information system in a spatiotemporal projection as we do in this study, the field implementation of microbial control against locust in an integrated pest management system may be improved. Finally, the practical utility of this model provides insights that may improve the timing of pesticide application in a selected area where efficacy is highly expected.
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20
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Gasmi S, Koffi JK, Nelder MP, Russell C, Graham-Derham S, Lachance L, Adhikari B, Badcock J, Baidoobonso S, Billard BA, Halfyard B, Jodoin S, Singal M, Bourgeois AC. Surveillance for Lyme disease in Canada, 2009-2019. CANADA COMMUNICABLE DISEASE REPORT = RELEVE DES MALADIES TRANSMISSIBLES AU CANADA 2022; 48:219-227. [PMID: 38105769 PMCID: PMC10723632 DOI: 10.14745/ccdr.v48i05a05] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Background Lyme disease (LD) is a multisystem infection that can affect the skin, heart, joints and nervous system. In Canada, the incidence of LD cases has increased over the past decade making this a disease of public health concern. The objective of this study is to summarize the epidemiology of LD cases reported in Canada from 2009 through 2019. Methods Incidence over time, case classification (confirmed and probable), seasonal and geographic distribution, demographic and clinical characteristics of reported LD cases were determined. Logistic regression was used to explore potential demographic risk factors for the occurrence of LD. Results During 2009-2019, a total of 10,150 LD cases were reported by the provinces to the Public Health Agency of Canada, of which 7,242 (71.3%) were confirmed and 2,908 (28.7%) were probable cases. The annual count increased from 144 in 2009 to 2,634 in 2019, mainly due to an increase in locally acquired infections, from 65.3% to 93.6%, respectively. The majority of cases (92.1%) were reported from three provinces: Ontario (46.0%); Nova Scotia (28.0%); and Québec (18.1%). Most of the locally acquired cases (74.0%) were reported in the summer months of June (20.0%), July (35.4%) and August (18.6%). The highest incidence rates (cases per 100,000 population) were in children aged 5-9 years (45.0) and in adults aged 65-69 years (74.3), with 57.3% of all reported cases occurring among males. The most common presenting symptoms were single erythema migrans rash (75.1%) and arthritis (34.1%). The frequency of reported clinical manifestations varied among age groups and seasons with erythema migrans and arthritis at presentation reported more frequently in children than older patients. Conclusion The results of this report highlight the continued emergence of LD in Canada and the need for further development and implementation of targeted awareness campaigns designed to minimize the burden of LD.
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Affiliation(s)
- Salima Gasmi
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Saint-Hyacinthe, QC
| | - Jules K Koffi
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Saint-Hyacinthe, QC
| | - Mark P Nelder
- Enteric, Zoonotic and Vector-Borne Diseases, Public Health Ontario, Toronto, ON
| | - Curtis Russell
- Enteric, Zoonotic and Vector-Borne Diseases, Public Health Ontario, Toronto, ON
| | - Scott Graham-Derham
- Communicable Disease Control Branch, Manitoba Health and Seniors Care, Winnipeg, MB
| | - Lisa Lachance
- Health and Wellness Promotion Branch, Public Health and Compliance Division, Alberta Health, Edmonton, AB
| | - Bijay Adhikari
- Population Health Branch, Ministry of Health, Regina, SK
| | - Jacqueline Badcock
- Office of the Chief Medical Officer of Health, New Brunswick Department of Health, Fredericton, NB
| | - Shamara Baidoobonso
- Prince Edward Island Department of Health and Wellness, Population Health Assessment & Surveillance Unit, Charlottetown, PE
| | - Beverly A Billard
- Public Health Branch, Nova Scotia Department of Health and Wellness, Halifax, NS
| | - Beth Halfyard
- Health and Community Services, Population Health Branch, St. John’s, NL
| | - Stéphanie Jodoin
- Direction générale adjointe de la protection de la santé publique, Ministère de la Santé et des Services sociaux, Québec, QC
| | - Mayank Singal
- Communicable Diseases and Immunization Service, BC Centre for Disease Control, Vancouver, BC
| | - Annie-Claude Bourgeois
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
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21
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Ackleh AS, Veprauskas A. Modeling the invasion and establishment of a tick-borne pathogen. Ecol Modell 2022; 467. [PMID: 35663375 PMCID: PMC9161809 DOI: 10.1016/j.ecolmodel.2022.109915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
We develop a discrete-time tick–host–pathogen model to describe the spread of a disease in a hard-bodied tick species. This model incorporates the developmental stages for a tick, the dependence of the tick life-cycle and disease transmission on host availability, and three sources of pathogen transmission. We first establish the global dynamics of the disease-free system. We then apply the model to two pathogens, Borellia burgdorferi and Anaplasma phagocytophila, using Ixodes ricinus as the tick species to study properties of the invasion and establishment of a disease numerically. In particular, we consider the basic reproduction number, which determines whether a disease can invade the tick-host system, as well as disease prevalence and time to establishment in the case of successful disease invasion. Using Monte Carlo simulations, we calculate the means of each of these disease metrics and their elasticities with respect to various model parameters. We find that increased tick survival may help enable disease invasion, decrease the time to disease establishment, and increase disease prevalence once established. In contrast, though disease invasion is sensitive to tick-to-host transmission and tick searching efficiencies, neither disease prevalence nor time to disease establishment is sensitive to these parameters. These differences emphasize the importance of developing approaches, such as the one highlighted here, that can be used to study disease dynamics beyond just pathogen invasion, including transitional and long-term dynamics.
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22
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De Pelsmaeker N, Korslund L, Steifetten Ø. Host in reserve: The role of common shrews (
Sorex araneus
) as a supplementary source of tick hosts in small mammal communities influenced by rodent population cycles. Ecol Evol 2022; 12:e8776. [PMID: 35432925 PMCID: PMC9001028 DOI: 10.1002/ece3.8776] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 03/06/2022] [Accepted: 03/13/2022] [Indexed: 11/17/2022] Open
Abstract
Rodents often act as important hosts for ticks and as pathogen reservoirs. At northern latitudes, rodents often undergo multi‐annual population cycles, and the periodic absence of certain hosts may inhibit the survival and recruitment of ticks. We investigated the potential role of common shrews (Sorex araneus) to serve as a supplementary host source to immature life stages (larvae and nymphs) of a generalist tick Ixodes ricinus and a small mammal specialist tick I. trianguliceps, during decreasing abundances of bank voles (Myodes glareolus). We used generalized mixed models to test whether ticks would have a propensity to parasitize a certain host species dependent on host population size and host population composition across two high‐latitude gradients in southern Norway, by comparing tick burdens on trapped animals. Host population size was defined as the total number of captured animals and host population composition as the proportion of voles to shrews. We found that a larger proportion of voles in the host population favored the parasitism of voles by I. ricinus larvae (estimate = −1.923, p = .039) but not by nymphs (estimate = −0.307, p = .772). I. trianguliceps larvae did not show a lower propensity to parasitize voles, regardless of host population composition (estimate = 0.875, p = .180), while nymphs parasitized shrews significantly more as vole abundance increased (estimate = 2.106, p = .002). These results indicate that common shrews may have the potential to act as a replacement host during periods of low rodent availability, but long‐term observations encompassing complete rodent cycles may determine whether shrews are able to maintain tick range expansion despite low rodent availability.
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Affiliation(s)
- Nicolas De Pelsmaeker
- Department of Nature, Health and Environment University of Southeastern Norway Bø Norway
| | - Lars Korslund
- Department of Natural Sciences University of Agder Kristiansand Norway
| | - Øyvind Steifetten
- Department of Nature, Health and Environment University of Southeastern Norway Bø Norway
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Bacon EA, Kopsco H, Gronemeyer P, Mateus-Pinilla N, Smith RL. Effects of Climate on the Variation in Abundance of Three Tick Species in Illinois. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:700-709. [PMID: 34875079 PMCID: PMC8924963 DOI: 10.1093/jme/tjab189] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Indexed: 06/01/2023]
Abstract
The range of ticks in North America has been steadily increasing likely, in part, due to climate change. Along with it, there has been a rise in cases of tick-borne disease. Among those medically important tick species of particular concern are Ixodes scapularis Say (Acari: Ixodidae), Dermacentor variabilis Say (Acari: Ixodidae), and Amblyomma americanum Linneaus (Acari: Ixodidae). The aim of this study was to determine if climate factors explain existing differences in abundance of the three aforementioned tick species between two climatically different regions of Illinois (Central and Southern), and if climate variables impact each species differently. We used both zero-inflated regression approaches and Bayesian network analyses to assess relationships among environmental variables and tick abundance. Results suggested that the maximum average temperature and total precipitation are associated with differential impact on species abundance and that this difference varied by region. Results also reinforced a differential level of resistance to desiccation among these tick species. Our findings help to further define risk periods of tick exposure for the general public, and reinforce the importance of responding to each tick species differently.
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Affiliation(s)
- E A Bacon
- College of Veterinary Medicine, University of Illinois, Urbana IL, USA
| | - H Kopsco
- College of Veterinary Medicine, University of Illinois, Urbana IL, USA
| | - P Gronemeyer
- College of Veterinary Medicine, University of Illinois, Urbana IL, USA
| | - N Mateus-Pinilla
- College of Veterinary Medicine, University of Illinois, Urbana IL, USA
| | - R L Smith
- College of Veterinary Medicine, University of Illinois, Urbana IL, USA
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Wu Y, Huang C. Climate Change and Vector-Borne Diseases in China: A Review of Evidence and Implications for Risk Management. BIOLOGY 2022; 11:biology11030370. [PMID: 35336744 PMCID: PMC8945209 DOI: 10.3390/biology11030370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary Vector-borne diseases are among the most rapidly spreading infectious diseases and are widespread all around the world. In China, many types of vector-borne diseases have been prevalent in different regions, which is a serious public health problem with significant association with meteorological factors and weather events. Under the background of current severe climate change, the outbreaks and transmission of vector-borne diseases have been proven to be impacted greatly due to rapidly changing weather conditions. This study summarizes research progress on the association between climate conditions and all types of vector-borne diseases in China. A total of seven insect-borne diseases, two rodent-borne diseases, and a snail-borne disease were included, among which dengue fever is the most concerning mosquito-borne disease. Temperature, rainfall, and humidity have the most significant effect on vector-borne disease transmission, while the association between weather conditions and vector-borne diseases shows vast differences in China. We also make suggestions about future research based on a review of current studies. Abstract Vector-borne diseases have posed a heavy threat to public health, especially in the context of climate change. Currently, there is no comprehensive review of the impact of meteorological factors on all types of vector-borne diseases in China. Through a systematic review of literature between 2000 and 2021, this study summarizes the relationship between climate factors and vector-borne diseases and potential mechanisms of climate change affecting vector-borne diseases. It further examines the regional differences of climate impact. A total of 131 studies in both Chinese and English on 10 vector-borne diseases were included. The number of publications on mosquito-borne diseases is the largest and is increasing, while the number of studies on rodent-borne diseases has been decreasing in the past two decades. Temperature, precipitation, and humidity are the main parameters contributing to the transmission of vector-borne diseases. Both the association and mechanism show vast differences between northern and southern China resulting from nature and social factors. We recommend that more future research should focus on the effect of meteorological factors on mosquito-borne diseases in the era of climate change. Such information will be crucial in facilitating a multi-sectorial response to climate-sensitive diseases in China.
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Affiliation(s)
- Yurong Wu
- Vanke School of Public Health, Tsinghua University, Beijing 100084, China;
- School of Public Health, Sun Yat-sen University, Guangzhou 510275, China
| | - Cunrui Huang
- Vanke School of Public Health, Tsinghua University, Beijing 100084, China;
- School of Public Health, Sun Yat-sen University, Guangzhou 510275, China
- Institute of Healthy China, Tsinghua University, Beijing 100084, China
- Correspondence:
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25
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Otálora-Luna F, Dickens JC, Brinkerhoff J, Li AY. Behavior of Nymphs and Adults of the Black-Legged Tick Ixodes scapularis and the Lone Star Tick Ambylomma americanum in Response to Thermal Stimuli. INSECTS 2022; 13:insects13020130. [PMID: 35206704 PMCID: PMC8876853 DOI: 10.3390/insects13020130] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 02/06/2023]
Abstract
Ticks use chemical and thermal signals emitted by humans and other vertebrates to locate suitable hosts for a blood meal. Here, we study the behavior of black-legged Ixodes scapularis and the lone star ticks Amblyomma americanum exposed to heat sources held at temperatures near those of vertebrate hosts (32 °C). First, we used a locomotion compensator to test behavioral responses of ticks to an infrared light emitting diode (LED). The servosphere allowed us to measure parameters such as velocity, acceleration, linearity, and orientation. Then a heating element (Peltier) located in one of the extremes of a double-choice vertical rod (flying T), was employed to observe upward movement of the ticks toward such a heat source. While both species oriented toward the LED, only lone star ticks were attracted to the Peltier element while climbing upward. In conclusion, we showed that heat attracted ticks from short distances up to several centimeters on a the servosphere, and those responses differed between the two species of ticks on the flying T. We discuss our results in the context of the ecology of both tick species and their potential in tick survey and management.
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Affiliation(s)
- Fernando Otálora-Luna
- Department of Biology, School of Art & Sciences, University of Richmond, Richmond, VA 23173, USA; (J.C.D.); (J.B.)
- Correspondence: ; Tel.: +1-(804)-549-9175
| | - Joseph C. Dickens
- Department of Biology, School of Art & Sciences, University of Richmond, Richmond, VA 23173, USA; (J.C.D.); (J.B.)
| | - Jory Brinkerhoff
- Department of Biology, School of Art & Sciences, University of Richmond, Richmond, VA 23173, USA; (J.C.D.); (J.B.)
| | - Andrew Y. Li
- Invasive Insect Biocontrol & Behavior Laboratory, USDA, ARS, Beltsville, MD 20705, USA;
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26
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Ginsberg HS, Hickling GJ, Pang G, Tsao JI, Fitzgerald M, Ross B, Rulison EL, Burke RL. Selective Host Attachment by Ixodes scapularis (Acari: Ixodidae): Tick-Lizard Associations in the Southeastern United States. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:267-272. [PMID: 34718657 DOI: 10.1093/jme/tjab181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Indexed: 06/13/2023]
Abstract
Questing behavior and host associations of immature blacklegged ticks, Ixodes scapularis Say, from the southeastern United States are known to differ from those in the north. To elucidate these relationships we describe host associations of larval and nymphal I. scapularis from 8 lizard species sampled from 5 sites in the southeastern U.S. Larvae and nymphs attached in greater numbers to larger lizards than to smaller lizards, with differential levels of attachment to different lizard species. Blacklegged ticks are generally attached to skinks of the genus Plestiodon in greater numbers per unit lizard weight than to anoles (Anolis) or fence lizards (Sceloporus). The broad-headed skink, Plestiodon laticeps (Schneider), was a particularly important host for immature I. scapularis in our study and in several previous studies of tick-host associations in the southeast. Blacklegged ticks show selective attachment to Plestiodon lizard hosts in the southeast, but whether this results from behavioral host preferences or from ecological factors such as timing or microhabitat distributions of tick questing and host activity remains to be determined.
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Affiliation(s)
- Howard S Ginsberg
- U.S. Geological Survey, Eastern Ecological Science Center, Field Station at the University of Rhode Island, Kingston, RI, USA
| | - Graham J Hickling
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, USA
| | - Genevieve Pang
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA
| | - Jean I Tsao
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA
| | - Meghan Fitzgerald
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN, USA
| | - Breann Ross
- Department of Biology, Hofstra University, Hempstead, NY, USA
| | - Eric L Rulison
- Department of Plant Sciences and Entomology, University of Rhode Island, Kingston, RI, USA
| | - Russell L Burke
- Department of Biology, Hofstra University, Hempstead, NY, USA
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27
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Hauser N, Conlon KC, Desai A, Kobziar LN. Climate Change and Infections on the Move in North America. Infect Drug Resist 2022; 14:5711-5723. [PMID: 35002262 PMCID: PMC8722568 DOI: 10.2147/idr.s305077] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 11/12/2021] [Indexed: 12/18/2022] Open
Abstract
Climate change is increasingly recognized for its impacts on human health, including how biotic and abiotic factors are driving shifts in infectious disease. Changes in ecological conditions and processes due to temperature and precipitation fluctuations and intensified disturbance regimes are affecting infectious pathogen transmission, habitat, hosts, and the characteristics of pathogens themselves. Understanding the relationships between climate change and infectious diseases can help clinicians broaden the scope of differential diagnoses when interviewing, diagnosing, and treating patients presenting with infections lacking obvious agents or transmission pathways. Here, we highlight key examples of how the mechanisms of climate change affect infectious diseases associated with water, fire, land, insects, and human transmission pathways in the hope of expanding the analytical framework for infectious disease diagnoses. Increased awareness of these relationships can help prepare both clinical physicians and epidemiologists for continued impacts of climate change on infectious disease in the future.
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Affiliation(s)
- Naomi Hauser
- Department of Medicine, Division of Infectious Disease, University of California Davis Health, Sacramento, CA, USA.,Climate Adaptation Research Center, University of California, Davis, CA, USA
| | - Kathryn C Conlon
- Climate Adaptation Research Center, University of California, Davis, CA, USA.,Department of Public Health Sciences, School of Medicine, University of California Davis, Davis, CA, USA.,Department of Veterinary Medicine & Epidemiology, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Angel Desai
- Department of Medicine, Division of Infectious Disease, University of California Davis Health, Sacramento, CA, USA
| | - Leda N Kobziar
- Department of Natural Resources and Society, University of Idaho, Coeur d'Alene, ID, USA
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28
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Zhang L, Ma D, Li C, Zhou R, Wang J, Liu Q. Projecting the Potential Distribution Areas of Ixodes scapularis (Acari: Ixodidae) Driven by Climate Change. BIOLOGY 2022; 11:biology11010107. [PMID: 35053104 PMCID: PMC8773098 DOI: 10.3390/biology11010107] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/06/2022] [Accepted: 01/07/2022] [Indexed: 11/16/2022]
Abstract
Ixodes scapularis is a vector of tick-borne diseases. Climate change is frequently invoked as an important cause of geographic expansions of tick-borne diseases. Environmental variables such as temperature and precipitation have an important impact on the geographical distribution of disease vectors. We used the maximum entropy model to project the potential geographic distribution and future trends of I. scapularis. The main climatic variables affecting the distribution of potential suitable areas were screened by the jackknife method. Arc Map 10.5 was used to visualize the projection results to better present the distribution of potential suitable areas. Under climate change scenarios, the potential suitable area of I. scapularis is dynamically changing. The largest suitable area of I. scapularis is under SSP3-7.0 from 2081 to 2100, while the smallest is under SSP5-8.5 from 2081 to 2100, even smaller than the current suitable area. Precipitation in May and September are the main contributing factors affecting the potential suitable areas of I. scapularis. With the opportunity to spread to more potential suitable areas, it is critical to strengthen surveillance to prevent the possible invasion of I. scapularis.
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Affiliation(s)
- Lu Zhang
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (L.Z.); (D.M.); (C.L.); (R.Z.); (J.W.)
| | - Delong Ma
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (L.Z.); (D.M.); (C.L.); (R.Z.); (J.W.)
- School of Public Health and Health Management, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan 250117, China
| | - Chao Li
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (L.Z.); (D.M.); (C.L.); (R.Z.); (J.W.)
- School of Public Health and Health Management, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan 250117, China
| | - Ruobing Zhou
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (L.Z.); (D.M.); (C.L.); (R.Z.); (J.W.)
| | - Jun Wang
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (L.Z.); (D.M.); (C.L.); (R.Z.); (J.W.)
| | - Qiyong Liu
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (L.Z.); (D.M.); (C.L.); (R.Z.); (J.W.)
- Shandong University Climate Change and Health Center, School of Public Health, Shandong University, Jinan 250012, China
- Correspondence: ; Tel.: +86-13910599152
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29
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Curriero FC, Wychgram C, Rebman AW, Corrigan AE, Kvit A, Shields T, Aucott JN. The Lyme and Tickborne Disease Dashboard: A map-based resource to promote public health awareness and research collaboration. PLoS One 2021; 16:e0260122. [PMID: 34851988 PMCID: PMC8635336 DOI: 10.1371/journal.pone.0260122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/02/2021] [Indexed: 11/19/2022] Open
Abstract
With the incidence of Lyme and other tickborne diseases on the rise in the US and globally, there is a critical need for data-driven tools that communicate the magnitude of this problem and help guide public health responses. We present the Johns Hopkins Lyme and Tickborne Disease Dashboard (https://www.hopkinslymetracker.org/), a new tool that harnesses the power of geography to raise awareness and fuel research and scientific collaboration. The dashboard is unique in applying a geographic lens to tickborne diseases, aiming not only to become a global tracker of tickborne diseases but also to contextualize their complicated geography with a comprehensive set of maps and spatial data sets representing a One Health approach. We share our experience designing and implementing the dashboard, describe the main features, and discuss current limitations and future directions.
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Affiliation(s)
- Frank C. Curriero
- Department of Epidemiology, Spatial Science for Public Health Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Cara Wychgram
- Department of Epidemiology, Spatial Science for Public Health Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
| | - Alison W. Rebman
- Division of Rheumatology, Department of Medicine, Lyme Disease Research Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Anne E. Corrigan
- Department of Epidemiology, Spatial Science for Public Health Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Anton Kvit
- Department of Epidemiology, Spatial Science for Public Health Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Timothy Shields
- Department of Epidemiology, Spatial Science for Public Health Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - John N. Aucott
- Division of Rheumatology, Department of Medicine, Lyme Disease Research Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
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30
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Ticks, Human Babesiosis and Climate Change. Pathogens 2021; 10:pathogens10111430. [PMID: 34832586 PMCID: PMC8625897 DOI: 10.3390/pathogens10111430] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 11/17/2022] Open
Abstract
The effects of current and future global warming on the distribution and activity of the primary ixodid vectors of human babesiosis (caused by Babesia divergens, B. venatorum and B. microti) are discussed. There is clear evidence that the distributions of both Ixodes ricinus, the vector in Europe, and I. scapularis in North America have been impacted by the changing climate, with increasing temperatures resulting in the northwards expansion of tick populations and the occurrence of I. ricinus at higher altitudes. Ixodes persulcatus, which replaces I. ricinus in Eurasia and temperate Asia, is presumed to be the babesiosis vector in China and Japan, but this tick species has not yet been confirmed as the vector of either human or animal babesiosis. There is no definite evidence, as yet, of global warming having an effect on the occurrence of human babesiosis, but models suggest that it is only a matter of time before cases occur further north than they do at present.
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Chala B, Hamde F. Emerging and Re-emerging Vector-Borne Infectious Diseases and the Challenges for Control: A Review. Front Public Health 2021; 9:715759. [PMID: 34676194 PMCID: PMC8524040 DOI: 10.3389/fpubh.2021.715759] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 09/07/2021] [Indexed: 01/22/2023] Open
Abstract
Vector-borne emerging and re-emerging diseases pose considerable public health problem worldwide. Some of these diseases are emerging and/or re-emerging at increasing rates and appeared in new regions in the past two decades. Studies emphasized that the interactions among pathogens, hosts, and the environment play a key role for the emergence or re-emergence of these diseases. Furthermore, social and demographic factors such as human population growth, urbanization, globalization, trade exchange and travel and close interactions with livestock have significantly been linked with the emergence and/or re-emergence of vector-borne diseases. Other studies emphasize the ongoing evolution of pathogens, proliferation of reservoir populations, and antimicrobial drug use to be the principal exacerbating forces for emergence and re-emergence of vector-borne infectious diseases. Still other studies equivocally claim that climate change has been associated with appearance and resurgence of vector-borne infectious diseases. Despite the fact that many important emerging and re-emerging vector-borne infectious diseases are becoming better controlled, our success in stopping the many new appearing and resurging vector-borne infectious diseases that may happen in the future seems to be uncertain. Hence, this paper reviews and synthesizes the existing literature to explore global patterns of emerging and re-emerging vector-borne infections and the challenges for their control. It also attempts to give insights to the epidemiological profile of major vector-borne diseases including Zika fever, dengue, West Nile fever, Crimean-Congo hemorrhagic fever, Chikungunya, Yellow fever, and Rift Valley fever.
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Affiliation(s)
- Bayissa Chala
- Department of Applied Biology, School of Applied Natural Science, Adama Science and Technology University, Adama, Ethiopia
| | - Feyissa Hamde
- Department of Applied Biology, School of Applied Natural Science, Adama Science and Technology University, Adama, Ethiopia
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Monitoring Risk: Tick and Borrelia burgdorferi Public Participatory Surveillance in the Canadian Maritimes, 2012-2020. Pathogens 2021; 10:pathogens10101284. [PMID: 34684234 PMCID: PMC8538556 DOI: 10.3390/pathogens10101284] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 11/17/2022] Open
Abstract
Ticks are vectors of many diseases, including Lyme disease (Ld). Lyme disease is an emerging disease in Canada caused by infection with the Lyme borreliosis (Lb) members of the Borrelia genus of spirochaete bacteria, of which Borrelia burgdorferi is regionally the most prevalent. The primary tick vector in central and eastern Canada, Ixodes scapularis, is increasing in numbers and in the geographical extent of established populations. This study documents the distribution of ticks recovered by passive surveillance, and their B. burgdorferi infection prevalence, in three Canadian Maritime provinces from 2012-2020. These regions represent areas in which tick populations are widely established, establishing, and considered non-established. Using a community science approach by partnering with veterinarians and members of the public, we collected over 7000 ticks from the 3 provinces. The three species found most often on companion animals and humans were I. scapularis (76.9%), Ixodes cookei (10.4%) and Dermacentor variabilis (8.9%). The most common hosts were dogs (60.5%), cats (16.8%) and humans (17.6%). As is typical of passive surveillance tick collections, the majority of ticks recovered were adult females; for I. scapularis 90.2%, 5.3%, 3.9% and 0.6% of the total of 5630 ticks recovered for this species were adult females, adult males, nymphs and larvae, respectively. The majority of B. burgdorferi-infected ticks were I. scapularis, as expected. Borrelia infection prevalence in I scapularis was higher in Nova Scotia (20.9%), the province with the most endemic regions, than New Brunswick (14.1%) and Prince Edward Island (9.1%), provinces thought to have established and non-established tick populations, respectively. The province-wide Borrelia infection prevalence generally increased in these latter tow provinces over the course of the study. The host did not have a significant effect on B. burgdorferi infection prevalence; I. scapularis ticks from dogs, cats, humans was, 13.3% (n = 3622), 15.6% (n = 817), 17.9% (n = 730), respectively. No I. scapularis larvae were found infected (n = 33) but B. burgdorferi was detected in 14.8% of both adults (n = 5140) and nymphs (n = 215). The incidence of B. burgdorferi infection also did not differ by engorgement status 15.0% (n = 367), 15.1% (n = 3101) and 14.4% (n = 1958) of non-engorged, engorged and highly engorged ticks, respectively, were infected. In New Brunswick, at the advancing front of tick population establishment, the province-wide infection percentages generally increased over the nine-year study period and all health district regions showed increased tick recoveries and a trend of increased percentages of Borrelia-infected ticks over the course of the study. Within New Brunswick, tick recoveries but not Borrelia infection prevalence were significantly different from endemic and non-endemic regions, suggesting cryptic endemic regions existed prior to their designation as a risk area. Over the 9 years of the study, tick recoveries increased in New Brunswick, the primary study region, and I. scapularis recoveries spread northwards and along the coast, most but not all new sites of recoveries were predicted by climate-based models, indicating that ongoing tick surveillance is necessary to accurately detect all areas of risk. Comparison of tick recoveries and public health risk areas indicates a lag in identification of risk areas. Accurate and timely information on tick distribution and the incidence of Borrelia and other infections are essential for keeping the public informed of risk and to support disease prevention behaviors.
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Poché DM, Dawson K, Tseveenjav B, Poché RM. Efficacy of low-dose fipronil bait against blacklegged tick (Ixodes scapularis) larvae feeding on white-footed mice (Peromyscus leucopus) under simulated field conditions. Parasit Vectors 2021; 14:459. [PMID: 34493330 PMCID: PMC8424918 DOI: 10.1186/s13071-021-04930-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 08/05/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Lyme disease, caused primarily by Borrelia burgdorferi sensu stricto, is the most prevalent vector-borne disease in the United States. Treatment of rodent pathogen reservoirs with an oral acaricide may suppress the production of infected host-seeking ticks posing a risk for human infection. A previous study showed that an oral fipronil bait effectively controlled larval Ixodes scapularis ticks on white-footed mice (Peromyscus leucopus) up to 15 days post-bait exposure. The present study expands upon this finding by exposing group-housed white-footed mice to fipronil bait under simulated field conditions prior to tick infestation. METHODS Mice (n = 80) were housed in groups of 10 within large enclosures and offered a choice between fipronil bait within a commercial bait station and an alternative diet. The mice were assigned to two treatment groups and two control groups to undergo bait exposure durations of either 24 h (reduced) or 168 h (extended). Groups were further differentiated by the time point post-bait exposure when larval ticks were applied to mice within feeding capsules (reduced day 1, day 15; extended day 21, day 35). For 4 days post-tick introduction, attached larvae were observed by microscopy and replete larvae were recovered. Replete larvae were monitored for molting success. Plasma was collected from all treatment group mice to obtain fipronil plasma concentrations (CP). RESULTS The fipronil bait (0.005% fipronil) was palatable and controlled larval ticks on white-footed mice when presented under simulated field conditions. Efficacy in preventing attached larvae from feeding to repletion was 100% (day 1), 89.0% (day 15), 85.8% (day 21), and 75.2% (day 35). When also considering molting success, the fipronil bait prevented 100% (day 1), 91.1% (day 15), 91.7% (day 21), and 82.5% (day 35) of larvae attaching to mice from molting. The mean CP per mouse was 191.5 ng/ml (day 1), 29.4 ng/ml (day 15), 10.6 ng/ml (day 21), and 1.0 ng/ml (day 35). CONCLUSIONS The results suggest that fipronil bait will be consumed by white-footed mice in the presence of an alternative diet, and effectively control larval ticks on treated mice. A field trial is needed to confirm the results of this study. Low-dose fipronil bait may provide a cost-effective means of controlling blacklegged ticks to be integrated into tick management programs.
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Tick infestation of birds across a gradient of urbanization intensity in the United States Great Plains. Urban Ecosyst 2021. [DOI: 10.1007/s11252-021-01160-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kopsco HL, Duhaime RJ, Mather TN. An analysis of companion animal tick encounters as revealed by photograph-based crowdsourced data. Vet Med Sci 2021; 7:2198-2208. [PMID: 34414695 PMCID: PMC8604111 DOI: 10.1002/vms3.586] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Background Community science is increasingly utilized to track important vectors of companion animal disease, providing a scalable, cost‐effective strategy for identifying new foci, changing phenology, and disease prevalence across wide geographies. Objectives We examined photographs of ticks found attached to predominately dogs and cats reported to a photograph‐based tick surveillance program to identify potential areas for improvements in tick prevention education and risk intervention. Methods We compared estimated days of tick attachment using a Kruskal–Wallis one‐way analysis of variance, and a Pearson's chi‐square analysis of variance on the number of submissions by host type submitted for each season. Results The blacklegged tick (Ixodes scapularis) was the most common species reported (39.8%). Tick photographs submitted were almost entirely adults (89.5%), and ticks found on companion animals exhibited an estimated median engorgement time of 2.5 days. Ixodes scapularis displayed the highest median engorgement of the top tick species found feeding on companion animals (χ2 = 98.96, p < 0.001). Ticks were spotted year‐round; during spring and summer, ticks collected from pets represented 15.4 and 12.8% of all submissions, but increased to 28.5 and 35.2% during autumn and winter, respectively. Conclusions Crowdsourced data reveal that mostly adult ticks are detected on pets, and they are found at a point in the blood‐feeding process that puts pets at heightened risk for disease transmission. The increase in proportion of ticks found on pets during colder months may reveal a critical knowledge gap amongst pet owners regarding seasonal activity of I. scapularis, a vector of Lyme disease, providing an opportunity for prevention‐education.
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Affiliation(s)
- Heather L Kopsco
- Center for Vector-Borne Disease, University of Rhode Island, Kingston, Rhode Island.,TickEncounter Resource Center, Kingston, Rhode Island.,Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Roland J Duhaime
- TickEncounter Resource Center, Kingston, Rhode Island.,Environmental Data Center, University of Rhode Island, Kingston, Rhode Island
| | - Thomas N Mather
- Center for Vector-Borne Disease, University of Rhode Island, Kingston, Rhode Island.,TickEncounter Resource Center, Kingston, Rhode Island
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O'Brien SF, Drews SJ, Yi QL, Bloch EM, Ogden NH, Koffi JK, Lindsay LR, Gregoire Y, Delage G. Risk of transfusion-transmitted Babesia microti in Canada. Transfusion 2021; 61:2958-2968. [PMID: 34272882 DOI: 10.1111/trf.16595] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 01/21/2023]
Abstract
BACKGROUND Babesia microti has gained a foothold in Canada as tick vectors become established in broader geographic areas. B. microti infection is associated with mild or no symptoms in healthy individuals but is transfusion-transmissible and can be fatal in immunocompromised individuals. This is the first estimate of clinically significant transfusion-transmitted babesiosis (TTB) risk in Canada. STUDY DESIGN AND METHODS The proportion of B. microti-antibody (AB)/nucleic acid amplification test (NAT)-positive whole blood donations was estimated at 5.5% of the proportion of the general population with reported Lyme Disease (also tick-borne) based on US data. Monte Carlo simulation estimated the number and proportion of infectious red cell units for three scenarios: base, localized incidence (risk in Manitoba only), and donor study informed (prevalence from donor data). The model simulated 1,029,800 donations repeated 100,000 times for each. RESULTS In the base scenario 0.5 (0.01, 1.75), B. microti-NAT-positive donations would be expected per year, with 0.08 (0, 0.38) recipients suffering clinically significant TTB (1 every 12.5 years). In the localized incidence scenario, there were 0.21(0, 0.7) B. microti-NAT-positive donations, with 0.04 (0, 0.14) recipient infections (about 1 every 25 years). In the donor study informed scenario, there were 4.6 (0.3, 15.8) B. microti-NAT-positive donations expected, and 0.81 (0.05, 3.14) clinically significant TTB cases per year. DISCUSSION The likelihood of clinically relevant TTB is low. Testing would have very little utility in Canada at this time. Ongoing pathogen surveillance in tick vectors is important as B. microti prevalence appears to be slowly increasing in Canada.
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Affiliation(s)
- Sheila F O'Brien
- Epidemiology & Surveillance, Canadian Blood Services, Ottawa, Ontario, Canada.,School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Steven J Drews
- Department of Microbiology, Canadian Blood Services, Edmonton, Alberta, Canada.,Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Qi-Long Yi
- Epidemiology & Surveillance, Canadian Blood Services, Ottawa, Ontario, Canada
| | - Evan M Bloch
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nicholas H Ogden
- Public Health Risk Sciences Division, National Microbiology Laboratory, Public Health Agency of Canada, Saint-Hyacinthe, Quebec, Canada
| | - Jules K Koffi
- Public Health Risk Sciences Division, National Microbiology Laboratory, Public Health Agency of Canada, Saint-Hyacinthe, Quebec, Canada
| | - Leslie Robbin Lindsay
- Zoonotic Diseases & Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Yves Gregoire
- Epidemiology and Statistics, Héma-Québec, Quebec City, Quebec, Canada
| | - Gilles Delage
- Medical Microbiology, Héma-Québec, Montreal, Quebec, Canada
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Ogden NH, Beard CB, Ginsberg HS, Tsao JI. Possible Effects of Climate Change on Ixodid Ticks and the Pathogens They Transmit: Predictions and Observations. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:1536-1545. [PMID: 33112403 PMCID: PMC9620468 DOI: 10.1093/jme/tjaa220] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Indexed: 05/09/2023]
Abstract
The global climate has been changing over the last century due to greenhouse gas emissions and will continue to change over this century, accelerating without effective global efforts to reduce emissions. Ticks and tick-borne diseases (TTBDs) are inherently climate-sensitive due to the sensitivity of tick lifecycles to climate. Key direct climate and weather sensitivities include survival of individual ticks, and the duration of development and host-seeking activity of ticks. These sensitivities mean that in some regions a warming climate may increase tick survival, shorten life-cycles and lengthen the duration of tick activity seasons. Indirect effects of climate change on host communities may, with changes in tick abundance, facilitate enhanced transmission of tick-borne pathogens. High temperatures, and extreme weather events (heat, cold, and flooding) are anticipated with climate change, and these may reduce tick survival and pathogen transmission in some locations. Studies of the possible effects of climate change on TTBDs to date generally project poleward range expansion of geographical ranges (with possible contraction of ranges away from the increasingly hot tropics), upslope elevational range spread in mountainous regions, and increased abundance of ticks in many current endemic regions. However, relatively few studies, using long-term (multi-decade) observations, provide evidence of recent range changes of tick populations that could be attributed to recent climate change. Further integrated 'One Health' observational and modeling studies are needed to detect changes in TTBD occurrence, attribute them to climate change, and to develop predictive models of public- and animal-health needs to plan for TTBD emergence.
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Affiliation(s)
- Nicholas H. Ogden
- Public Health Risk Sciences Division, National Microbiology Laboratory, Public Health Agency of Canada, St-Hyacinthe, QC, Canada J2S 2M2
- Groupe de recherche en épidémiologie des zoonoses et santé publique (GREZOSP), Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, QC, Canada J2S 2M2
- Corresponding author,
| | - C. Ben Beard
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521
| | - Howard S. Ginsberg
- U.S. Geological Survey, Patuxent Wildlife Research Center, Rhode Island Field Station, University of Rhode Island, Kingston, RI 02881
| | - Jean I. Tsao
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824
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Evidence-based communication on climate change and health: Testing videos, text, and maps on climate change and Lyme disease in Manitoba, Canada. PLoS One 2021; 16:e0252952. [PMID: 34111202 PMCID: PMC8191974 DOI: 10.1371/journal.pone.0252952] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 05/25/2021] [Indexed: 11/19/2022] Open
Abstract
Given the climate crisis and its cumulative impacts on public health, effective communication strategies that engage the public in adaptation and mitigation are critical. Many have argued that a health frame increases engagement, as do visual methodologies including online and interactive platforms, yet to date there has been limited research on audience responses to health messaging using visual interventions. This study explores public attitudes regarding communication tools focused on climate change and climate-affected Lyme disease through six focus groups (n = 61) in rural and urban southern Manitoba, Canada. The results add to the growing evidence of the efficacy of visual and storytelling methods in climate communications and argues for a continuum of mediums: moving from video, text, to maps. Findings underscore the importance of tailoring both communication messages and mediums to increase uptake of adaptive health and environmental behaviours, for some audiences bridging health and climate change while for others strategically decoupling them.
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Ratti V, Winter JM, Wallace DI. Dilution and amplification effects in Lyme disease: Modeling the effects of reservoir-incompetent hosts on Borrelia burgdorferi sensu stricto transmission. Ticks Tick Borne Dis 2021; 12:101724. [PMID: 33878571 DOI: 10.1016/j.ttbdis.2021.101724] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 11/19/2022]
Abstract
The literature on Lyme disease includes a lively debate about the paradoxical role of changing deer populations. A decrease in the number of deer will both (1) reduce the incidence of Lyme disease by decreasing the host populations for ticks and therefore tick populations, and (2) enhance the incidence of Lyme disease by offering fewer reservoir-incompetent hosts for ticks, forcing the vector to choose reservoir-competent, and therefore possibly diseased, hosts to feed on. A review of field studies exploring the net impact of changing deer populations shows mixed results. In this manuscript, we investigate the hypothesis that the balance of these two responses to changing deer populations depends on the relative population sizes of reservoir-competent vs. reservoir-incompetent hosts and the presence of host preference in larval and adult stages. A temperature driven seasonal model of Borrelia burgdorferi sensu stricto (cause of Lyme disease) transmission among three host types (reservoir-competent infected and uninfected hosts, and reservoir-incompetent hosts) is constructed as a system of nonlinear ordinary differential equations. The model, which produces biologically reasonable results for both the tick vector Ixodes scapularis Say 1921 and the hosts, is used to investigate the effects of reservoir-incompetent host removal on both tick populations and disease prevalence for various relative population sizes of reservoir-competent hosts vs. reservoir-incompetent hosts. In summary, the simulation results show that the model with host preference appears to be more accurate than the one with no host preference. Given these results, we found that removal of adult I. scapularis(Say) hosts is likely to reduce questing nymph populations. At very low levels questing adult abundance may rise with lack of adult hosts. There is a dilution effect at low reservoir-competent host populations and there is an amplification effect at high reservoir-competent host populations.
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Affiliation(s)
- Vardayani Ratti
- Department of Mathematics and Statistics, California State University Chico, CA, United States.
| | - Jonathan M Winter
- Department of Geography, Dartmouth College, Hanover, NH, United States
| | - Dorothy I Wallace
- Department of Mathematics, Dartmouth College, Hanover, NH, United States
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Della-Giustina D, Duke C, Goldflam K. Underrecognized Tickborne Illnesses: Borrelia Miyamotoi and Powassan Virus. Wilderness Environ Med 2021; 32:240-246. [PMID: 33839017 DOI: 10.1016/j.wem.2021.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 11/16/2022]
Abstract
Over the past 2 decades, tickborne disease has been increasingly recognized as a threat to humans as a result of the growing geographic range of ticks. This review describes 2 tickborne diseases, Borrelia miyamotoi and Powassan virus, that likely have a significant impact on humans, yet are underdiagnosed compared to most other tickborne diseases. We performed a literature search from 2015 to 2020. Borrelia miyamotoi is a tickborne pathogen that infects and co-infects ticks along with other pathogens, including Borrelia burgdorferi. Because B miyamotoi infects the same Ixodes ticks as B burgdorferi, B miyamotoi may cover a similar geographic range. B miyamotoi infection may be underdiagnosed for 2 reasons. First, a presumptive treatment approach to Lyme disease may result in B miyamotoi infection treatment without identification of the actual cause. Second, the absence of readily available testing and diagnostic criteria makes it difficult to diagnose B miyamotoi infection. Powassan virus is a tickborne flavivirus similar to the dengue virus. Powassan virus disease appears to have an asymptomatic or minimally symptomatic presentation in most people but can cause devastating and fatal encephalitis. The Powassan virus may be transmitted in less than 15 min of tick feeding. Powassan virus disease is a difficult diagnosis because testing capabilities are limited and because there may be co-infection with other tickborne pathogens.
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Affiliation(s)
| | - Charles Duke
- Yale School of Medicine, Department of Emergency Medicine, New Haven, CT
| | - Katja Goldflam
- Yale School of Medicine, Department of Emergency Medicine, New Haven, CT
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41
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Convergence Research for Emerging Zoonoses. Trends Parasitol 2021; 37:465-467. [PMID: 33858779 DOI: 10.1016/j.pt.2021.03.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/18/2021] [Accepted: 03/18/2021] [Indexed: 12/26/2022]
Abstract
Global emergence of vector-borne and zoonotic diseases presents a rapidly growing 'wicked' problem. We outline the need for a transdisciplinary research program that is grounded in ecological and evolutionary theory but integrates fundamentally with research perspectives spanning the health, social, and natural sciences.
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42
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Cameron L, Rocque R, Penner K, Mauro I. Public perceptions of Lyme disease and climate change in southern Manitoba, Canada: making a case for strategic decoupling of climate and health messages. BMC Public Health 2021; 21:617. [PMID: 33781235 PMCID: PMC8008613 DOI: 10.1186/s12889-021-10614-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 03/11/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Despite scientific evidence that climate change has profound and far reaching implications for public health, translating this knowledge in a manner that supports citizen engagement, applied decision-making, and behavioural change can be challenging. This is especially true for complex vector-borne zoonotic diseases such as Lyme disease, a tick-borne disease which is increasing in range and impact across Canada and internationally in large part due to climate change. This exploratory research aims to better understand public risk perceptions of climate change and Lyme disease in order to increase engagement and motivate behavioural change. METHODS A focus group study involving 61 participants was conducted in three communities in the Canadian Prairie province of Manitoba in 2019. Focus groups were segmented by urban, rural, and urban-rural geographies, and between participants with high and low levels of self-reported concern regarding climate change. RESULTS Findings indicate a broad range of knowledge and risk perceptions on both climate change and Lyme disease, which seem to reflect the controversy and complexity of both issues in the larger public discourse. Participants in high climate concern groups were found to have greater climate change knowledge, higher perception of risk, and less skepticism than those in low concern groups. Participants outside of the urban centre were found to have more familiarity with ticks, Lyme disease, and preventative behaviours, identifying differential sources of resilience and vulnerability. Risk perceptions of climate change and Lyme disease were found to vary independently rather than correlate, meaning that high climate change risk perception did not necessarily indicate high Lyme disease risk perception and vice versa. CONCLUSIONS This research contributes to the growing literature framing climate change as a public health issue, and suggests that in certain cases climate and health messages might be framed in a way that strategically decouples the issue when addressing climate skeptical audiences. A model showing the potential relationship between Lyme disease and climate change perceptions is proposed, and implications for engagement on climate change health impacts are discussed.
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Affiliation(s)
- Laura Cameron
- Prairie Climate Centre, University of Winnipeg, 515 Portage Ave, Winnipeg, Manitoba, R3B 2E9, Canada.
| | - Rhéa Rocque
- Prairie Climate Centre, University of Winnipeg, 515 Portage Ave, Winnipeg, Manitoba, R3B 2E9, Canada
| | - Kailey Penner
- Prairie Climate Centre, University of Winnipeg, 515 Portage Ave, Winnipeg, Manitoba, R3B 2E9, Canada
| | - Ian Mauro
- Prairie Climate Centre, University of Winnipeg, 515 Portage Ave, Winnipeg, Manitoba, R3B 2E9, Canada.
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Couper LI, MacDonald AJ, Mordecai EA. Impact of prior and projected climate change on US Lyme disease incidence. GLOBAL CHANGE BIOLOGY 2021; 27:738-754. [PMID: 33150704 PMCID: PMC7855786 DOI: 10.1111/gcb.15435] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/28/2020] [Indexed: 05/21/2023]
Abstract
Lyme disease is the most common vector-borne disease in temperate zones and a growing public health threat in the United States (US). The life cycles of the tick vectors and spirochete pathogen are highly sensitive to climate, but determining the impact of climate change on Lyme disease burden has been challenging due to the complex ecology of the disease and the presence of multiple, interacting drivers of transmission. Here we incorporated 18 years of annual, county-level Lyme disease case data in a panel data statistical model to investigate prior effects of climate variation on disease incidence while controlling for other putative drivers. We then used these climate-disease relationships to project Lyme disease cases using CMIP5 global climate models and two potential climate scenarios (RCP4.5 and RCP8.5). We find that interannual variation in Lyme disease incidence is associated with climate variation in all US regions encompassing the range of the primary vector species. In all regions, the climate predictors explained less of the variation in Lyme disease incidence than unobserved county-level heterogeneity, but the strongest climate-disease association detected was between warming annual temperatures and increasing incidence in the Northeast. Lyme disease projections indicate that cases in the Northeast will increase significantly by 2050 (23,619 ± 21,607 additional cases), but only under RCP8.5, and with large uncertainty around this projected increase. Significant case changes are not projected for any other region under either climate scenario. The results demonstrate a regionally variable and nuanced relationship between climate change and Lyme disease, indicating possible nonlinear responses of vector ticks and transmission dynamics to projected climate change. Moreover, our results highlight the need for improved preparedness and public health interventions in endemic regions to minimize the impact of further climate change-induced increases in Lyme disease burden.
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Affiliation(s)
- Lisa I Couper
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Andrew J MacDonald
- Earth Research Institute, University of California, Santa Barbara, CA, USA
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, USA
| | - Erin A Mordecai
- Department of Biology, Stanford University, Stanford, CA, USA
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Winter JM, Partridge TF, Wallace D, Chipman JW, Ayres MP, Osterberg EC, Dekker ER. Modeling the Sensitivity of Blacklegged Ticks (Ixodes scapularis) to Temperature and Land Cover in the Northeastern United States. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:416-427. [PMID: 32901803 DOI: 10.1093/jme/tjaa179] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Indexed: 06/11/2023]
Abstract
The prevalence of Lyme disease and other tick-borne diseases is dramatically increasing across the United States. While the rapid rise in Lyme disease is clear, the causes of it are not. Modeling Ixodes scapularis Say (Acari: Ixodidae), the primary Lyme disease vector in the eastern United States, presents an opportunity to disentangle the drivers of increasing Lyme disease, including climate, land cover, and host populations. We improved upon a recently developed compartment model of ordinary differential equations that simulates I. scapularis growth, abundance, and infection with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) by adding land cover effects on host populations, refining the representation of growth stages, and evaluating output against observed data. We then applied this model to analyze the sensitivity of simulated I. scapularis dynamics across temperature and land cover in the northeastern United States. Specifically, we ran an ensemble of 232 simulations with temperature from Hanover, New Hampshire and Storrs, Connecticut, and land cover from Hanover and Cardigan in New Hampshire, and Windsor and Danielson in Connecticut. Consistent with observations, simulations of I. scapularis abundance are sensitive to temperature, with the warmer Storrs climate significantly increasing the number of questing I. scapularis at all growth stages. While there is some variation in modeled populations of I. scapularis infected with B. burgdorferi among land cover distributions, our analysis of I. scapularis response to land cover is limited by a lack of observations describing host populations, the proportion of hosts competent to serve as B. burgdorferi reservoirs, and I. scapularis abundance.
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Affiliation(s)
- Jonathan M Winter
- Department of Geography, Dartmouth College, Hanover, NH
- Department of Earth Sciences, Dartmouth College, Hanover, NH
| | | | | | - Jonathan W Chipman
- Department of Geography, Dartmouth College, Hanover, NH
- Department of Earth Sciences, Dartmouth College, Hanover, NH
| | - Matthew P Ayres
- Department of Biological Sciences, Dartmouth College, Hanover, NH
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Abstract
Ticks exist on all continents and carry more zoonotic pathogens than any other type of vector. Ticks spend most of their lives in the external environment away from the host and are thus expected to be affected by changes in climate. Most empirical and theoretical studies demonstrate or predict range shifts or increases in ticks and tick-borne diseases, but there can be a lot of heterogeneity in such predictions. Tick-borne disease systems are complex, and determining whether changes are due to climate change or other drivers can be difficult. Modeling studies can help tease apart and understand the roles of different drivers of change. Predictive models can also be invaluable in projecting changes according to different climate change scenarios. However, validating these models remains challenging, and estimating uncertainty in predictions is essential. Another focus for future research should be assessing the resilience of ticks and tick-borne pathogens to climate change.
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Affiliation(s)
- Lucy Gilbert
- Institute for Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, United Kingdom;
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46
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Harnessing the Four Horsemen of Climate Change: A Framework for Deep Resilience, Decarbonization, and Planetary Health in Ontario, Canada. SUSTAINABILITY 2021. [DOI: 10.3390/su13010379] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Widespread implementation of nature-based solutions like green infrastructure, provides a multi-functional strategy to increase climate resilience, enhance ecological connectivity, create healthier communities, and support sustainable urban development. This paper presents a decision-support framework to facilitate adoption of green infrastructure within communities using the Climate Change Local Adaptation Action Model (CCLAAM) developed for this purpose. It also presents an ecosystems-based approach to bridging the gap between climate change mitigation and adaptation actions in Ontario, Canada. Green infrastructure could be a viable strategy to address multiple climate change impacts and support the implementation of the UN Sustainable Development Goals (SDGs).
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47
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Drake C, Coyne M, McCrann DJ, Buch J, Mack R. Risk of Development of Chronic Kidney Disease After Exposure to Borrelia burgdorferi and Anaplasma spp. Top Companion Anim Med 2020; 42:100491. [PMID: 33152525 DOI: 10.1016/j.tcam.2020.100491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 10/14/2020] [Accepted: 10/30/2020] [Indexed: 01/12/2023]
Abstract
Lyme disease is a multi-faceted illness caused by infection due to Borrelia burgdorferi. Acute kidney damage secondary to Lyme disease is well described but less so as a chronic event. The role of Anaplasma spp. and secondary kidney dysfunction is not known. A retrospective cohort study was performed to determine if dogs within a defined Lyme disease and anaplasmosis region with B. burgdorferi or Anaplasma spp. antibodies had an increased risk of chronic kidney disease (CKD). Patient exposure was defined as having a B. burgdorferi or Anaplasma spp. antibody positive result recorded at any point in the available patient history. CKD was defined as concurrent increased symmetric dimethylarginine and creatinine (Cr) for a minimum of 25 days with inappropriate urine specific gravity (USG). Patients were matched using propensity scoring to control for age, region, and breed. Contingency tables were used to compare dogs seropositive and not seropositive to B. burgdorferi and Anaplasma spp. and CKD outcome. For each comparison that was performed, statistical significance was defined by a P-value of <.025. The risk ratio of CKD for patients exposed to B. burgdorferi and Anaplasma spp. were found to be 1.43 (95% confidence interval [CI, 1.27, 1.61], P < .0001) and 1.04, (95% CI [0.87, 1.24], P = .6485), respectively. Results suggest in this cohort no increased risk for developing CKD when exposed to Anaplasma spp. but a significant increase in risk for developing CKD with exposure to B. burgdorferi.
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Affiliation(s)
- Corie Drake
- IDEXX Laboratories, Inc., Westbrook, ME 04092, USA
| | | | | | - Jesse Buch
- IDEXX Laboratories, Inc., Westbrook, ME 04092, USA
| | - Rebekah Mack
- IDEXX Laboratories, Inc., Westbrook, ME 04092, USA
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Hess J, Boodram LLG, Paz S, Stewart Ibarra AM, Wasserheit JN, Lowe R. Strengthening the global response to climate change and infectious disease threats. BMJ 2020; 371:m3081. [PMID: 33106244 PMCID: PMC7594144 DOI: 10.1136/bmj.m3081] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jeremy Hess
- Departments of Emergency Medicine, Environmental and Occupational Health Sciences, and Global Health, and Center for Health and the Global Environment, Schools of Medicine and Public Health, University of Washington, Seattle, WA USA
| | | | - Shlomit Paz
- Department of Geography and Environmental Studies, University of Haifa, Haifa, Israel
| | - Anna M Stewart Ibarra
- Inter-American Institute for Global Change Research (IAI), Montevideo, Department of Montevideo, Uruguay
| | - Judith N Wasserheit
- Departments of Global Health and Medicine, Schools of Medicine and Public Health, University of Washington, Seattle, WA USA
| | - Rachel Lowe
- Centre on Climate Change & Planetary Health and Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, UK
- Barcelona Institute for Global Health (ISGlobal), Spain
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Aguilar-Vega C, Bosch J, Fernández-Carrión E, Lucientes J, Sánchez-Vizcaíno JM. Identifying Spanish Areas at More Risk of Monthly BTV Transmission with a Basic Reproduction Number Approach. Viruses 2020; 12:E1158. [PMID: 33066209 PMCID: PMC7602074 DOI: 10.3390/v12101158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/08/2020] [Accepted: 10/12/2020] [Indexed: 01/24/2023] Open
Abstract
Bluetongue virus (BTV) causes a disease that is endemic in Spain and its two major biological vector species, C. imicola and the Obsoletus complex species, differ greatly in their ecology and distribution. Understanding the seasonality of BTV transmission in risk areas is key to improving surveillance and control programs, as well as to better understand the pathogen transmission networks between wildlife and livestock. Here, monthly risk transmission maps were generated using risk categories based on well-known BTV R0 equations and predicted abundances of the two most relevant vectors in Spain. Previously, Culicoides spp. predicted abundances in mainland Spain and the Balearic Islands were obtained using remote sensing data and random forest machine learning algorithm. Risk transmission maps were externally assessed with the estimated date of infection of BTV-1 and BTV-4 historical outbreaks. Our results highlight the differences in risk transmission during April-October, June-August being the period with higher R0 values. Likewise, a natural barrier has been identified between northern and central-southern areas at risk that may hamper BTV spread between them. Our results can be relevant to implement risk-based interventions for the prevention, control and surveillance of BTV and other diseases shared between livestock and wildlife host populations.
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Affiliation(s)
- Cecilia Aguilar-Vega
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary Medicine, Complutense University of Madrid, 28040 Madrid, Spain; (J.B.); (E.F.-C.); (J.M.S.-V.)
| | - Jaime Bosch
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary Medicine, Complutense University of Madrid, 28040 Madrid, Spain; (J.B.); (E.F.-C.); (J.M.S.-V.)
| | - Eduardo Fernández-Carrión
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary Medicine, Complutense University of Madrid, 28040 Madrid, Spain; (J.B.); (E.F.-C.); (J.M.S.-V.)
| | - Javier Lucientes
- Department of Animal Pathology (Animal Health), AgriFood Institute of Aragón IA2, Faculty of Veterinary Medicine, University of Zaragoza, 50013 Zaragoza, Spain;
| | - José Manuel Sánchez-Vizcaíno
- VISAVET Health Surveillance Centre, Animal Health Department, Faculty of Veterinary Medicine, Complutense University of Madrid, 28040 Madrid, Spain; (J.B.); (E.F.-C.); (J.M.S.-V.)
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Addressing challenges in routine health data reporting in Burkina Faso through Bayesian spatiotemporal prediction of weekly clinical malaria incidence. Sci Rep 2020; 10:16568. [PMID: 33024162 PMCID: PMC7538437 DOI: 10.1038/s41598-020-73601-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 09/07/2020] [Indexed: 11/15/2022] Open
Abstract
Sub-Saharan African (SSA) countries’ health systems are often vulnerable to unplanned situations that can hinder their effectiveness in terms of data completeness and disease control. For instance, in Burkina Faso following a workers' strike, comprehensive data on several diseases were unavailable for a long period in 2019. Weather, seasonal-malaria-chemoprevention (SMC), free healthcare, and other contextual data, which are purported to influence malarial disease, provide opportunities to fit models to describe the clinical malaria data and predict the disease spread. Bayesian spatiotemporal modeling was applied to weekly malaria surveillance data from Burkina Faso (2011–2018) while considering the effects of weather, health programs and contextual factors. Then, a prediction was used to deal with weekly missing data for the entire year of 2019, and SMC and free healthcare effects were quantified. Our proposed model accurately predicted weekly clinical malaria incidence (correlation coefficient, r = 0.90). The distribution of clinical malaria incidence was heterogeneous across the country. Overall, national predicted clinical malaria incidence in 2019 (605 per 1000 [95% CrI: 360–990]) increased by 24.7% compared with the year 2015. SMC and the interaction between free healthcare and health facility attendance were associated with a reduction in clinical malaria incidence. Our modeling approach could be a useful tool for strengthening health systems’ resilience by addressing data completeness and could support SSA countries in developing appropriate targets and indicators to facilitate the subnational control effort.
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