1
|
Diallo AO, Banek K, Kashamuka MM, Bala JAM, Nkalani M, Kihuma G, Nseka TM, Atibu JL, Mahilu GE, McCormick L, White SJ, Sendor R, Sinai C, Keeler C, Herman C, Emch M, Sompwe E, Thwai KL, Dinglasan RR, Rogier E, Juliano JJ, Tshefu AK, Parr JB. Impact of malaria diagnostic choice on monitoring of Plasmodium falciparum prevalence estimates in the Democratic Republic of the Congo and relevance to control programs in high-burden countries. PLOS Glob Public Health 2023; 3:e0001375. [PMID: 37494361 PMCID: PMC10370698 DOI: 10.1371/journal.pgph.0001375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 06/09/2023] [Indexed: 07/28/2023]
Abstract
Malaria programs rely upon a variety of diagnostic assays, including rapid diagnostic tests (RDTs), microscopy, polymerase chain reaction (PCR), and bead-based immunoassays (BBA), to monitor malaria prevalence and support control and elimination efforts. Data comparing these assays are limited, especially from high-burden countries like the Democratic Republic of the Congo (DRC). Using cross-sectional and routine data, we compared diagnostic performance and Plasmodium falciparum prevalence estimates across health areas of varying transmission intensity to illustrate the relevance of assay performance to malaria control programs. Data and samples were collected between March-June 2018 during a cross-sectional household survey across three health areas with low, moderate, and high transmission intensities within Kinshasa Province, DRC. Samples from 1,431 participants were evaluated using RDT, microscopy, PCR, and BBA. P. falciparum parasite prevalence varied between diagnostic methods across all health areas, with the highest prevalence estimates observed in Bu (57.4-72.4% across assays), followed by Kimpoko (32.6-53.2%), and Voix du Peuple (3.1-8.4%). Using latent class analysis to compare these diagnostic methods against an "alloyed gold standard," the most sensitive diagnostic method was BBA in Bu (high prevalence) and Voix du Peuple (low prevalence), while PCR diagnosis was most sensitive in Kimpoko (moderate prevalence). RDTs were consistently the most specific diagnostic method in all health areas. Among 9.0 million people residing in Kinshasa Province in 2018, the estimated P. falciparum prevalence by microscopy, PCR, and BBA were nearly double that of RDT. Comparison of malaria RDT, microscopy, PCR, and BBA results confirmed differences in sensitivity and specificity that varied by endemicity, with PCR and BBA performing best for detecting any P. falciparum infection. Prevalence estimates varied widely depending on assay type for parasite detection. Inherent differences in assay performance should be carefully considered when using community survey and surveillance data to guide policy decisions.
Collapse
Affiliation(s)
- Alpha Oumar Diallo
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Kristin Banek
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | | | | | - Marthe Nkalani
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Georges Kihuma
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Tommy Mambulu Nseka
- Programme National de Lutte Contre Paludisme, Kinshasa, Democratic Republic of the Congo
| | - Joseph Losoma Atibu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Georges Emo Mahilu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Lauren McCormick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Samuel J. White
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Rachel Sendor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Cyrus Sinai
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Corinna Keeler
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Camelia Herman
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Eric Sompwe
- Programme National de Lutte Contre Paludisme, Kinshasa, Democratic Republic of the Congo
| | - Kyaw Lay Thwai
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Rhoel R. Dinglasan
- University of Florida Emerging Pathogens Institute, Department of Infectious Diseases & Immunology, College of Veterinary Medicine, Gainesville, Florida, United States of America
| | - Eric Rogier
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Jonathan J. Juliano
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Antoinette Kitoto Tshefu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jonathan B. Parr
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| |
Collapse
|
2
|
Dhingra R, Keeler C, Staley BS, Jardel HV, Ward-Caviness C, Rebuli ME, Xi Y, Rappazzo K, Hernandez M, Chelminski AN, Jaspers I, Rappold AG. Wildfire smoke exposure and early childhood respiratory health: a study of prescription claims data. Environ Health 2023; 22:48. [PMID: 37370168 PMCID: PMC10294519 DOI: 10.1186/s12940-023-00998-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023]
Abstract
Wildfire smoke is associated with short-term respiratory outcomes including asthma exacerbation in children. As investigations into developmental wildfire smoke exposure on children's longer-term respiratory health are sparse, we investigated associations between developmental wildfire smoke exposure and first use of respiratory medications. Prescription claims from IBM MarketScan Commercial Claims and Encounters database were linked with wildfire smoke plume data from NASA satellites based on Metropolitan Statistical Area (MSA). A retrospective cohort of live infants (2010-2016) born into MSAs in six western states (U.S.A.), having prescription insurance, and whose birthdate was estimable from claims data was constructed (N = 184,703); of these, gestational age was estimated for 113,154 infants. The residential MSA, gestational age, and birthdate were used to estimate average weekly smoke exposure days (smoke-day) for each developmental period: three trimesters, and two sequential 12-week periods post-birth. Medications treating respiratory tract inflammation were classified using active ingredient and mode of administration into three categories:: 'upper respiratory', 'lower respiratory', 'systemic anti-inflammatory'. To evaluate associations between wildfire smoke exposure and medication usage, Cox models associating smoke-days with first observed prescription of each medication category were adjusted for infant sex, birth-season, and birthyear with a random intercept for MSA. Smoke exposure during postnatal periods was associated with earlier first use of upper respiratory medications (1-12 weeks: hazard ratio (HR) = 1.094 per 1-day increase in average weekly smoke-day, 95%CI: (1.005,1.191); 13-24 weeks: HR = 1.108, 95%CI: (1.016,1.209)). Protective associations were observed during gestational windows for both lower respiratory and systemic anti-inflammatory medications; it is possible that these associations may be a consequence of live-birth bias. These findings suggest wildfire smoke exposure during early postnatal developmental periods impact subsequent early life respiratory health.
Collapse
Affiliation(s)
- Radhika Dhingra
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, University of North Carolina, 135 Dauer Drive, C.B 7431, Chapel Hill, NC, 27599, USA.
- Brody School of Medicine, East Carolina University, Greenville, NC, USA.
| | - Corinna Keeler
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Brooke S Staley
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Hanna V Jardel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Durham, NC, USA
| | - Cavin Ward-Caviness
- Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Durham, NC, USA
| | - Meghan E Rebuli
- Department of Pediatrics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Yuzhi Xi
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, University of North Carolina, 135 Dauer Drive, C.B 7431, Chapel Hill, NC, 27599, USA
| | - Kristen Rappazzo
- Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Durham, NC, USA
| | - Michelle Hernandez
- Department of Pediatrics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ann N Chelminski
- Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Durham, NC, USA
| | - Ilona Jaspers
- Department of Pediatrics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ana G Rappold
- Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Durham, NC, USA
| |
Collapse
|
3
|
Keeler C, Luben TJ, Forestieri N, Olshan AF, Desrosiers TA. Is residential proximity to polluted sites during pregnancy associated with preterm birth or low birth weight? Results from an integrated exposure database in North Carolina (2003-2015). J Expo Sci Environ Epidemiol 2023; 33:229-236. [PMID: 36100666 PMCID: PMC10008762 DOI: 10.1038/s41370-022-00475-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/30/2022] [Accepted: 08/31/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Preterm birth (PTB) and term low birth weight (LBW) have been associated with pollution and other environmental exposures, but the relationship between these adverse outcomes and specific characteristics of polluted sites is not well studied. OBJECTIVES We conducted a retrospective cohort study to examine relationships between residential proximity to polluted sites in North Carolina (NC) and PTB and LBW. We further stratified exposure to polluted sites by route of contaminant emissions and specific contaminants released at each site. METHODS We created an integrated exposure geodatabase of polluted sites in NC from 2002 to 2015 including all landfills, Superfund sites, and industrial sites. Using birth certificates, we assembled a cohort of 1,494,651 singleton births in NC from 2003 to 2015. We geocoded the gestational parent residential address on the birth certificate, and defined exposure to polluted sites as residence within one mile of a site. We used log-binomial regression models to estimate adjusted risk ratios (aRR) and 95% confidence intervals (CI). Binomial models were used to estimate adjusted risk differences (aRD) per 10,000 births and 95% CIs for associations between exposure to polluted sites and PTB or LBW. RESULTS We observed weak associations between residential proximity to polluted sites and PTB [aRR(95% CI): 1.07(1.06,1.09); aRD(95% CI): 61(48,74)] and LBW [aRR(95% CI): 1.09(1.06,1.12); aRD(95% CI): 24(17,31)]. Secondary analyses showed increased risk of both PTB and LBW among births exposed to sites characterized by water emissions, air emissions, and land impoundment. In analyses of specific contaminants, increased risk of PTB was associated with proximity to sites containing arsenic, benzene, cadmium, lead, mercury, and polycyclic aromatic hydrocarbons. LBW was associated with exposure to arsenic, benzene, cadmium, lead, and mercury. SIGNIFICANCE This study provides evidence for potential reproductive health effects of polluted sites, and underscores the importance of accounting for heterogeneity between polluted sites when considering these exposures. IMPACT STATEMENT We documented an overall increased risk of both PTB and LBW in births with gestational exposure to polluted sites using a harmonized geodatabase of three site types, and further examined exposures stratified by site characteristics (route of emission, specific contaminants present). We observed increased risk of both PTB and LBW among births exposed to sites with water emissions or air emissions, across site types. Increased risk of PTB was associated with gestational proximity to sites containing arsenic, benzene, cadmium, lead, mercury, and polycyclic aromatic hydrocarbons; increased risk of LBW was associated with exposure to arsenic, benzene, cadmium, lead, and mercury.
Collapse
Affiliation(s)
- Corinna Keeler
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Thomas J Luben
- Center for Public Health and Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Durham, NC, USA
| | - Nina Forestieri
- Birth Defects Monitoring Program, State Center for Health Statistics, Division of Public Health, North Carolina Department of Health and Human Services, Raleigh, NC, USA
| | - Andrew F Olshan
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Tania A Desrosiers
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| |
Collapse
|
4
|
Deutsch-Feldman M, Parr JB, Keeler C, Brazeau NF, Goel V, Emch M, Edwards JK, Kashamuka M, Tshefu AK, Meshnick SR. The Burden of Malaria in the Democratic Republic of the Congo. J Infect Dis 2021; 223:1948-1952. [PMID: 33057671 PMCID: PMC8176632 DOI: 10.1093/infdis/jiaa650#supplementary-data] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 10/12/2020] [Indexed: 10/05/2023] Open
Abstract
Despite evidence that older children and adolescents bear the highest burden of malaria, large malaria surveys focus on younger children. We used polymerase chain reaction data from the 2013-2014 Demographic and Health Survey in the Democratic Republic of Congo (including children aged <5 years and adults aged ≥15 years) and a longitudinal study in Kinshasa Province (participants aged 6 months to 98 years) to estimate malaria prevalence across age strata. We fit linear models and estimated prevalences for each age category; adolescents aged 10-14 years had the highest prevalence. We estimate approximately 26 million polymerase chain reaction-detectable infections nationally. Adolescents and older children should be included in surveillance studies.
Collapse
Affiliation(s)
- Molly Deutsch-Feldman
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jonathan B Parr
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Nicholas F Brazeau
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Varun Goel
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Michael Emch
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jessie K Edwards
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Melchior Kashamuka
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of the Congo
| | - Antoinette K Tshefu
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of the Congo
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| |
Collapse
|
5
|
Brandt K, Goel V, Keeler C, Bell GJ, Aiello AE, Corbie-Smith G, Wilson E, Fleischauer A, Emch M, Boyce RM. SARS-CoV-2 testing in North Carolina: Racial, ethnic, and geographic disparities. Health Place 2021; 69:102576. [PMID: 33915376 PMCID: PMC8212571 DOI: 10.1016/j.healthplace.2021.102576] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 04/07/2021] [Accepted: 04/09/2021] [Indexed: 01/03/2023]
Abstract
SARS-CoV-2 testing data in North Carolina during the first three months of the state's COVID-19 pandemic were analyzed to determine if there were disparities among intersecting axes of identity including race, Latinx ethnicity, age, urban-rural residence, and residence in a medically underserved area. Demographic and residential data were used to reconstruct patterns of testing metrics (including tests per capita, positive tests per capita, and test positivity rate which is an indicator of sufficient testing) across race-ethnicity groups and urban-rural populations separately. Across the entire sample, 13.1% (38,750 of 295,642) of tests were positive. Within racial-ethnic groups, 11.5% of all tests were positive among non-Latinx (NL) Whites, 22.0% for NL Blacks, and 66.5% for people of Latinx ethnicity. The test positivity rate was higher among people living in rural areas across all racial-ethnic groups. These results suggest that in the first three months of the COVID-19 pandemic, access to COVID-19 testing in North Carolina was not evenly distributed across racial-ethnic groups, especially in Latinx, NL Black and other historically marginalized populations, and further disparities existed within these groups by gender, age, urban-rural status, and residence in a medically underserved area.
Collapse
Affiliation(s)
- Katerina Brandt
- UNC Department of Geography, Chapel Hill, NC, USA; Carolina Population Center, Chapel Hill, NC, USA
| | - Varun Goel
- UNC Department of Geography, Chapel Hill, NC, USA; Carolina Population Center, Chapel Hill, NC, USA
| | | | | | - Allison E Aiello
- Carolina Population Center, Chapel Hill, NC, USA; UNC Department of Epidemiology, Chapel Hill, NC, USA
| | | | - Erica Wilson
- North Carolina Department of Health and Human Services, Raleigh, NC, USA
| | - Aaron Fleischauer
- North Carolina Department of Health and Human Services, Raleigh, NC, USA
| | - Michael Emch
- UNC Department of Geography, Chapel Hill, NC, USA; Carolina Population Center, Chapel Hill, NC, USA; UNC Department of Epidemiology, Chapel Hill, NC, USA.
| | - Ross M Boyce
- Division of Infectious Diseases, UNC School of Medicine, Chapel Hill, NC, USA.
| |
Collapse
|
6
|
Deutsch-Feldman M, Parr JB, Keeler C, Brazeau NF, Goel V, Emch M, Edwards JK, Kashamuka M, Tshefu AK, Meshnick SR. The Burden of Malaria in the Democratic Republic of the Congo. J Infect Dis 2020; 223:1948-1952. [PMID: 33057671 DOI: 10.1093/infdis/jiaa650] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 10/12/2020] [Indexed: 01/31/2023] Open
Abstract
Despite evidence that older children and adolescents bear the highest burden of malaria, large malaria surveys focus on younger children. We used polymerase chain reaction data from the 2013-2014 Demographic and Health Survey in the Democratic Republic of Congo (including children aged <5 years and adults aged ≥15 years) and a longitudinal study in Kinshasa Province (participants aged 6 months to 98 years) to estimate malaria prevalence across age strata. We fit linear models and estimated prevalences for each age category; adolescents aged 10-14 years had the highest prevalence. We estimate approximately 26 million polymerase chain reaction-detectable infections nationally. Adolescents and older children should be included in surveillance studies.
Collapse
Affiliation(s)
- Molly Deutsch-Feldman
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jonathan B Parr
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Nicholas F Brazeau
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Varun Goel
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Michael Emch
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jessie K Edwards
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Melchior Kashamuka
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of the Congo
| | - Antoinette K Tshefu
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of the Congo
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| |
Collapse
|
7
|
Mitchell CL, Brazeau NF, Keeler C, Mwandagalirwa MK, Tshefu AK, Juliano JJ, Meshnick SR. Under the Radar: Epidemiology of Plasmodium ovale in the Democratic Republic of the Congo. J Infect Dis 2020; 223:1005-1014. [PMID: 32766832 DOI: 10.1093/infdis/jiaa478] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 07/28/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Plasmodium ovale is an understudied malaria species prevalent throughout much of sub-Saharan Africa. Little is known about the distribution of ovale malaria and risk factors for infection in areas of high malaria endemicity. METHODS Using the 2013 Democratic Republic of the Congo (DRC) Demographic and Health Survey, we conducted a risk factor analysis for P. ovale infections. We evaluated geographic clustering of infections and speciated to P. ovale curtisi and P. ovale wallikeri through deep sequencing. RESULTS Of 18 149 adults tested, we detected 143 prevalent P. ovale infections (prevalence estimate 0.8%; 95% confidence interval [CI], .59%-.98%). Prevalence ratios (PR) for significant risk factors were: male sex PR = 2.12 (95% CI, 1.38-3.26), coprevalent P. falciparum PR = 3.52 (95% CI, 2.06-5.99), and rural residence PR = 2.19 (95% CI, 1.31-3.66). P. ovale was broadly distributed throughout the DRC; an elevated cluster of infections was detected in the south-central region. Speciation revealed P. ovale curtisi and P. ovale wallikeri circulating throughout the country. CONCLUSIONS P. ovale persists broadly in the DRC, a high malaria burden country. For successful elimination of all malaria species, P. ovale needs to be on the radar of malaria control programs.
Collapse
Affiliation(s)
- Cedar L Mitchell
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Nicholas F Brazeau
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Melchior Kashamuka Mwandagalirwa
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA.,Kinshasa School of Public Health, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Antoinette K Tshefu
- Kinshasa School of Public Health, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Jonathan J Juliano
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA.,Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.,Curriculum in Genetics and Molecular Biology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA.,Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| |
Collapse
|
8
|
Brazeau NF, Assefa A, Mohammed H, Seme H, Tsadik AG, Parr JB, Keeler C, Hathaway NJ, Meshnick SR, Bailey JA, Kassa M, Juliano JJ, Woyessa A. Pooled Deep Sequencing of Drug Resistance Loci from Plasmodium falciparum Parasites across Ethiopia. Am J Trop Med Hyg 2020; 101:1139-1143. [PMID: 31516103 DOI: 10.4269/ajtmh.19-0142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Although Ethiopia has an overall lower prevalence of Plasmodium falciparum among countries in Africa, the emergence of drug resistance could seriously hinder elimination efforts. Using samples collected from five therapeutic efficacy studies conducted in 2007-11, we evaluated the prevalence of putative drug resistance mutations in the pfcrt, pfmdr1, and kelch13 genes at the time of those studies, as well as the ama1 gene for genetic relatedness using a pooled amplicon deep sequencing approach. Among all sites, the kelch13 gene showed no mutations, whereas the pfcrt CVIET genotype was fixed in all populations. By contrast, the mdr1 gene demonstrated frequencies of resistant genotypes ranging from 10 to 100% at amino acid position 86 and from 0% to 57.8% at amino acid position 1246. Although we observed a low degree of haplotype sharing between sites, we did observe considerable haplotype sharing within sites over time. This suggests that P. falciparum populations in Ethiopia are isolated and able to persist through time.
Collapse
Affiliation(s)
- Nicholas F Brazeau
- Doctor of Medicine/Doctor of Philosophy Program, School of Medicine, University of North Carolina, Chapel Hill, North Carolina.,Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | | | | | - Heven Seme
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Abeba G Tsadik
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Jonathan B Parr
- Division of Infectious Diseases, School of Medicine, University of North Carolina, Chapel Hill, North Carolina
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina
| | - Nicholas J Hathaway
- School of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Jeffrey A Bailey
- Division of Transfusion Medicine, Brown University, Providence, Rhode Island
| | - Moges Kassa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Jonathan J Juliano
- Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina.,Division of Infectious Diseases, School of Medicine, University of North Carolina, Chapel Hill, North Carolina.,Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Adugna Woyessa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| |
Collapse
|
9
|
Parr JB, Lodge EK, Holzmayer V, Pepin J, Frost EH, Fried MW, McGivern DR, Lemon SM, Keeler C, Emch M, Mwandagalirwa K, Tshefu A, Fwamba F, Muwonga J, Meshnick SR, Cloherty G. An Efficient, Large-Scale Survey of Hepatitis C Viremia in the Democratic Republic of the Congo Using Dried Blood Spots. Clin Infect Dis 2019; 66:254-260. [PMID: 29048459 DOI: 10.1093/cid/cix771] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 08/24/2017] [Indexed: 02/07/2023] Open
Abstract
Background Efficient viral load testing is needed for hepatitis C (HCV) surveillance and diagnosis. HCV viral load testing using dried blood spots (DBSs), made with a single drop of finger-prick whole blood on filter paper, is a promising alternative to traditional serum- or plasma-based approaches. Methods We adapted the Abbott Molecular m2000 instrument for high-throughput HCV viremia testing using DBSs with simple specimen processing and applied these methods to estimate the national burden of infection in the Democratic Republic of the Congo (DRC). We tested DBSs collected during the 2013-2014 DRC Demographic and Health Survey, including 1309 adults ≥40 years of age. HCV-positive samples underwent targeted sequencing, genotyping, and phylogenetic analyses. Results This high-throughput screening approach reliably identified HCV RNA extracted from DBSs prepared using whole blood, with a 95% limit of detection of 1196 (95% confidence interval [CI], 866-2280) IU/mL for individual 6-mm punches and 494 (95% CI, 372-1228) IU/mL for larger 12-mm punches. Fifteen infections were identified among samples from the DRC Demographic and Health Survey; the weighted country-wide prevalence of HCV viremia was 0.9% (95% CI, 0.3%-1.6%) among adults ≥40 years of age and 0.7% (95% CI, .6%-.8%) among human immunodeficiency virus-infected subjects. All successfully genotyped cases were due to genotype 4 infection. Conclusions DBS-based HCV testing represents a useful tool for the diagnosis and surveillance of HCV viremia and can easily be incorporated into specimen referral systems. Among adults ≥40 years of age in the DRC, 100000-200000 may have active infection and be eligible for treatment.
Collapse
Affiliation(s)
- Jonathan B Parr
- Division of Infectious Diseases, Department of Medicine, University of North Carolina, Chapel Hill
| | - Evans K Lodge
- School of Medicine, University of North Carolina, Chapel Hill
| | | | | | | | - Michael W Fried
- Division of Gastroenterology, Department of Medicine, University of North Carolina, Chapel Hill
| | - David R McGivern
- Division of Infectious Diseases, Department of Medicine, University of North Carolina, Chapel Hill
| | - Stanley M Lemon
- Division of Infectious Diseases, Department of Medicine, University of North Carolina, Chapel Hill
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill
| | - Michael Emch
- Department of Geography, University of North Carolina, Chapel Hill.,Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina, Chapel Hill
| | - Kashamuka Mwandagalirwa
- Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina, Chapel Hill.,Kinshasa School of Public Health, Kinshasa, Democratic Republic of Congo
| | - Antoinette Tshefu
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of Congo
| | - Franck Fwamba
- National AIDS Control Program, Kinshasa, Democratic Republic of Congo
| | - Jérémie Muwonga
- National AIDS Control Program, Kinshasa, Democratic Republic of Congo
| | - Steven R Meshnick
- Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina, Chapel Hill
| | | |
Collapse
|
10
|
Brazeau NF, Whitesell AN, Doctor SM, Keeler C, Mwandagalirwa MK, Tshefu AK, Likwela JL, Juliano JJ, Meshnick SR. Plasmodium vivax Infections in Duffy-Negative Individuals in the Democratic Republic of the Congo. Am J Trop Med Hyg 2019; 99:1128-1133. [PMID: 30203741 DOI: 10.4269/ajtmh.18-0277] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Although Plasmodium vivax has been assumed to be absent from sub-Saharan Africa because of the protective mutation conferring the Duffy-negative phenotype, recent evidence has suggested that P. vivax cases are prevalent in these regions. We selected 292 dried blood spots from children who participated in the 2013-2014 Demographic and Health Survey of the Democratic Republic of the Congo (DRC), to assess for P. vivax infection. Four P. vivax infections were identified by polymerase chain reaction, each in a geographically different survey cluster. Using these as index cases, we tested the remaining 73 samples from the four clusters. With this approach, 10 confirmed cases, three probable cases, and one possible case of P. vivax were identified. Among the 14 P. vivax cases, nine were coinfected with Plasmodium falciparum. All 14 individuals were confirmed to be Duffy-negative by sequencing for the single point mutation in the GATA motif that represses the expression of the Duffy antigen. This finding is consistent with a growing body of literature that suggests that P. vivax can infect Duffy-negative individuals in Africa. Future molecular and sequencing work is needed to understand the relationship of these isolates with other P. vivax samples from Asia and South America and discover variants linked to P. vivax virulence and erythrocyte invasion.
Collapse
Affiliation(s)
- Nicholas F Brazeau
- Medical Scientist Training Program, University of North Carolina School of Medicine, Chapel Hill, North Carolina.,Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Amy N Whitesell
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Stephanie M Doctor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina
| | | | - Antoinette K Tshefu
- Programme National de la Lutte Contre le Paludisme, Kinshasa, Democratic Republic of Congo
| | - Joris L Likwela
- Kinshasa School of Public Health, Kinshasa, Democratic Republic of the Congo
| | - Jonathan J Juliano
- Division of Infectious Diseases, School of Medicine, University of North Carolina, Chapel Hill, North Carolina.,Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| |
Collapse
|
11
|
Wang LT, Bwambale R, Keeler C, Reyes R, Muhindo R, Matte M, Ntaro M, Mulogo E, Sundararajan R, Boyce RM. Private sector drug shops frequently dispense parenteral anti-malarials in a rural region of Western Uganda. Malar J 2018; 17:305. [PMID: 30134987 PMCID: PMC6106765 DOI: 10.1186/s12936-018-2454-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 08/10/2018] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Malaria is a leading cause of paediatric morbidity and mortality in Uganda. More than half of febrile children in rural areas initially seek care at private clinics and drug shops. These shops are generally unregulated and the quality of clinical care is variable, with the potential for misdiagnosis and the development of drug resistance. There is thus an urgent need to identify rural drug shops and coordinate their malaria treatment efforts with those of the public sector. The objective of the study was to identify all drug shops in the Bugoye sub-county of Western Uganda and assess their anti-malarial dispensing practices. METHODS This study is a cross-sectional survey of drug shops in a rural sub-county of Western Uganda. In the first phase, shop locations, licensing and shopkeeper's qualifications, and supply and pricing of anti-malarials were characterized. In the second phase, the proportion of anti-malarials dispensed by private drug shops was compared to public health facilities. RESULTS A total of 48 drug shops were identified. Only one drug shop (1 of 48, 2%) was licensed with the sub-county's records office. The drug shops stocked a variety of anti-malarials, including first-line therapies and less effective agents (e.g., sulfadoxine/pyrimethamine). Almost all drug shops (45 of 48, 94%) provided parenteral anti-malarials. Of the 3900 individuals who received anti-malarials during the study, 2080 (53.3%) purchased anti-malarials through the private sector compared to 1820 (46.7%) who obtained anti-malarials through the public sector. Drug shops were the primary source of parenteral anti-malarials. Inadequate dosing of anti-malarials was more common in drug shops. CONCLUSIONS Drug shops are major sources of parenteral anti-malarials, which should be reserved for cases of severe malaria. Strengthening malaria case management and incorporating drug shops in future interventions is necessary to optimize malaria control efforts in the sub-county, and in similarly endemic regions.
Collapse
Affiliation(s)
- Lawrence T Wang
- School of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
| | - Robert Bwambale
- Bugoye Level III Health Centre, Uganda Ministry of Health, Bugoye, Kasese District, Western Region, Uganda
| | - Corinna Keeler
- Department of Geography, University of North Carolina at Chapel Hill, Campus Box 3220, Chapel Hill, NC, 27599, USA
| | - Raquel Reyes
- Division of General Medicine & Clinical Epidemiology, University of North Carolina at Chapel Hill, 5039 Old Clinic Building, CB 7110, Chapel Hill, 27599, USA
| | - Rabbison Muhindo
- Department of Community Health, Mbarara University of Science & Technology, P.O. Box 1410, Mbarara, Uganda
| | - Michael Matte
- Department of Community Health, Mbarara University of Science & Technology, P.O. Box 1410, Mbarara, Uganda
| | - Moses Ntaro
- Department of Community Health, Mbarara University of Science & Technology, P.O. Box 1410, Mbarara, Uganda
| | - Edgar Mulogo
- Department of Community Health, Mbarara University of Science & Technology, P.O. Box 1410, Mbarara, Uganda
| | - Radhika Sundararajan
- Department of Emergency Medicine, Weill Cornell Medical College, 525 East 68th Street, New York, NY, 10065, USA
| | - Ross M Boyce
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, 130 Mason Farm Road, Chapel Hill, NC, 27599, USA
| |
Collapse
|
12
|
Willcox AC, Collins MH, Jadi R, Keeler C, Parr JB, Mumba D, Kashamuka M, Tshefu A, de Silva AM, Meshnick SR. Seroepidemiology of Dengue, Zika, and Yellow Fever Viruses among Children in the Democratic Republic of the Congo. Am J Trop Med Hyg 2018; 99:756-763. [PMID: 29988000 DOI: 10.4269/ajtmh.18-0156] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Flaviviruses such as Zika, dengue, and yellow fever cause epidemics throughout the tropics and account for substantial global morbidity and mortality. Although malaria and other vector-borne diseases have long been appreciated in Africa, flavivirus epidemiology is incompletely understood. Despite the existence of an effective vaccine, yellow fever continues to cause outbreaks and deaths, including at least 42 fatalities in the Democratic Republic of the Congo (DRC) in 2016. Here, we leveraged biospecimens collected as part of the nationally representative 2013-2014 Demographic and Health Survey in the DRC to examine serological evidence of flavivirus infection or vaccination in children aged 6 months to 5 years. Even in this young stratum of the Congolese population, we find evidence of infection by dengue and Zika viruses based on results from enzyme-linked immunosorbent assay and neutralization assay. Surprisingly, there was remarkable discordance between reported yellow fever vaccination status and results of serological assays. The estimated seroprevalences of neutralizing antibodies against each virus are yellow fever, 6.0% (95% confidence interval [CI] = 4.6-7.5%); dengue, 0.4% (0.1-0.9%); and Zika, 0.1% (0.0-0.5%). These results merit targeted, prospective studies to assess effectiveness of yellow fever vaccination programs, determine flavivirus seroprevalence across a broader age range, and investigate how these emerging diseases contribute to the burden of acute febrile illness in the DRC.
Collapse
Affiliation(s)
- Alexandra C Willcox
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Matthew H Collins
- Department of Medicine, Division of Infectious Diseases, Hope Clinic of the Emory Vaccine Center, Emory School of Medicine, Decatur, Georgia
| | - Ramesh Jadi
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina
| | - Jonathan B Parr
- Department of Medicine, Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Dieudonné Mumba
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
| | - Melchior Kashamuka
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Antoinette Tshefu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Aravinda M de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| |
Collapse
|
13
|
Boyce R, Reyes R, Keeler C, Matte M, Ntaro M, Mulogo E, Siedner MJ. Anemia was an Uncommon Complication of Severe Malaria in a High-Transmission Rural Area of Western Uganda. Am J Trop Med Hyg 2017; 98:683-691. [PMID: 29280423 DOI: 10.4269/ajtmh.17-0681] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The clinical epidemiology of severe malaria among patients presenting to peripheral health centers has not been well described. We conducted a prospective, observational cohort study to describe the epidemiology and clinical manifestations of severe malaria in a highland area of declining transmission intensity in Western Uganda. Individuals presenting with a history of fever were screened with a malaria rapid diagnostic test (RDT). We prepared blood smears and conducted clinical and laboratory testing for those with a positive RDT. We defined severe malaria in accordance with World Health Organization guidelines for research and epidemiological studies. A total of 6,641 individuals underwent testing for malaria. Ninety-six of 1,462 (6.6%) participants with confirmed parasitemia satisfied the criteria for severe malaria. The incidence of severe malaria peaked between 2 and 3 years of age (incidence rate ratio = 17.1, 95% confidence interval = 8.4-34.9, P < 0.001) and then declined steadily until age 10. However, we also found a second peak among those ≥ 50 years of age. Severe anemia was uncommon, detected in only 5.3% of cases. Instead, shock (22.2%) and lactic acidosis (19.4%) were most frequently encountered. Our results suggest that the clinical characteristics of severe malaria presenting to rural, peripheral health centers may be different than previously observed in referral centers. These findings merit further investigation into the optimal methods for identification and management of severe malaria in rural health centers in the region.
Collapse
Affiliation(s)
- Ross Boyce
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Raquel Reyes
- Division of General Medicine & Clinical Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Corinna Keeler
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Michael Matte
- Department of Community Health, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Moses Ntaro
- Department of Community Health, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Edgar Mulogo
- Department of Community Health, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Mark J Siedner
- Department of Medicine, Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts
| |
Collapse
|
14
|
Parr JB, Verity R, Doctor SM, Janko M, Carey-Ewend K, Turman BJ, Keeler C, Slater HC, Whitesell AN, Mwandagalirwa K, Ghani AC, Likwela JL, Tshefu AK, Emch M, Juliano JJ, Meshnick SR. Pfhrp2-Deleted Plasmodium falciparum Parasites in the Democratic Republic of the Congo: A National Cross-sectional Survey. J Infect Dis 2017; 216:36-44. [PMID: 28177502 DOI: 10.1093/infdis/jiw538] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 11/02/2016] [Indexed: 11/14/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) account for more than two-thirds of malaria diagnoses in Africa. Deletions of the Plasmodium falciparum hrp2 (pfhrp2) gene cause false-negative RDT results and have never been investigated on a national level. Spread of pfhrp2-deleted P. falciparum mutants, resistant to detection by HRP2-based RDTs, would represent a serious threat to malaria elimination efforts. Methods Using a nationally representative cross-sectional study of 7,137 children under five years of age from the Democratic Republic of Congo (DRC), we tested 783 subjects with RDT-/PCR+ results using PCR assays to detect and confirm deletions of the pfhrp2 gene. Spatial and population genetic analyses were employed to examine the distribution and evolution of these parasites. Results We identified 149 pfhrp2-deleted parasites, representing 6.4% of all P. falciparum infections country-wide (95% confidence interval 5.1-8.0%). Bayesian spatial analyses identified statistically significant clustering of pfhrp2 deletions near Kinshasa and Kivu. Population genetic analysis revealed significant genetic differentiation between wild-type and pfhrp2-deleted parasite populations (GST = .046, p ≤ .00001). Conclusions Pfhrp2-deleted P. falciparum is a common cause of RDT-/PCR+ malaria among asymptomatic children in the DRC and appears to be clustered within select communities. Surveillance for these deletions is needed, and alternatives to HRP2-specific RDTs may be necessary.
Collapse
Affiliation(s)
- Jonathan B Parr
- Division of Infectious Diseases, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Robert Verity
- Department of Infectious Disease Epidemiology, Imperial College, London, United Kingdom
| | - Stephanie M Doctor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Mark Janko
- Department of Geography, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Kelly Carey-Ewend
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Breanna J Turman
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Hannah C Slater
- Department of Infectious Disease Epidemiology, Imperial College, London, United Kingdom
| | - Amy N Whitesell
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Kashamuka Mwandagalirwa
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
- University of Kinshasa School of Public Health, Kinshasa, Democratic Republic of Congo
| | - Azra C Ghani
- Department of Infectious Disease Epidemiology, Imperial College, London, United Kingdom
| | - Joris L Likwela
- Programme National de la Lutte contre le Paludisme, Kinshasa, Democratic Republic of Congo
| | - Antoinette K Tshefu
- University of Kinshasa School of Public Health, Kinshasa, Democratic Republic of Congo
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Geography, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jonathan J Juliano
- Division of Infectious Diseases, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Steven R Meshnick
- Division of Infectious Diseases, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| |
Collapse
|
15
|
Ngondi JM, Ishengoma DS, Doctor SM, Thwai KL, Keeler C, Mkude S, Munishi OM, Willilo RA, Lalji S, Kaspar N, Kitojo C, Paxton LA, Hathaway NJ, Bailey JA, Juliano JJ, Meshnick SR, Gutman J. Surveillance for sulfadoxine-pyrimethamine resistant malaria parasites in the Lake and Southern Zones, Tanzania, using pooling and next-generation sequencing. Malar J 2017; 16:236. [PMID: 28583119 PMCID: PMC5460401 DOI: 10.1186/s12936-017-1886-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 05/30/2017] [Indexed: 11/16/2022] Open
Abstract
Background Malaria in pregnancy (MiP) remains a major public health challenge in areas of high malaria transmission. Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended to prevent the adverse consequences of MiP. The effectiveness of SP for IPTp may be reduced in areas where the dhps581 mutation (a key marker of high level SP resistance) is found; this mutation was previously reported to be common in the Tanga Region of northern Tanzania, but there are limited data from other areas. The frequency of molecular markers of SP resistance was investigated in malaria parasites from febrile patients at health centres (HC) in seven regions comprising the Lake and Southern Zones of mainland Tanzania as part of the ongoing efforts to generate national-wide data of SP resistance. Methods A cross-sectional survey was conducted in the outpatient departments of 14 HCs in seven regions from April to June, 2015. 1750 dried blood spot (DBS) samples were collected (117 to 160 per facility) from consenting patients with positive rapid diagnostic tests for malaria, and no recent (within past 2 months) exposure to SP or related drugs. DNA was extracted from the DBS, pooled by HC, and underwent pooled targeted amplicon deep sequencing to yield estimates of mutated parasite allele frequency at each locus of interest. Results The dhps540 mutation was common across all 14 sites, ranging from 55 to 98.4% of sequences obtained. Frequency of the dhps581 mutation ranged from 0 to 2.4%, except at Kayanga HC (Kagera Region, Lake Zone) where 24.9% of sequences obtained were mutated. The dhfr164 mutation was detected only at Kanyanga HC (0.06%). Conclusion By pooling DNA extracts, the allele frequency of mutations in 14 sites could be directly determined on a single deep-sequencing run. The dhps540 mutant was very common at all locations. Surprisingly, the dhps581 was common at one health center, but rare in all the others, suggesting that there is geographic micro-heterogeneity in mutant distribution and that accurate surveillance requires inclusion of multiple sites. A better understanding of the effect of the dhps581 mutant on the efficacy of IPTp-SP is needed.
Collapse
Affiliation(s)
| | | | | | - Kyaw L Thwai
- UNC Gillings School of Global Public Health, Chapel Hill, NC, USA
| | - Corinna Keeler
- UNC Gillings School of Global Public Health, Chapel Hill, NC, USA
| | - Sigsbert Mkude
- National Malaria Control Programme, Dar es Salaam, Tanzania
| | | | | | | | - Naomi Kaspar
- US President's Malaria Initiative/United States Agency for International Development, Dar es Salaam, Tanzania
| | - Chonge Kitojo
- US President's Malaria Initiative/United States Agency for International Development, Dar es Salaam, Tanzania
| | - Lynn A Paxton
- US President's Malaria Initiative, Malaria Branch, Division of Parasitic Diseases and Malaria, US Centers for Disease Control and Prevention, Dar es Salaam, Tanzania
| | - Nicholas J Hathaway
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Jeffrey A Bailey
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | | | | | - Julie Gutman
- Malaria Branch, Division of Parasitic Diseases and Malaria, US Centers for Disease Control and Prevention, Atlanta, GA, USA.
| |
Collapse
|
16
|
Doctor SM, Liu Y, Anderson OG, Whitesell AN, Mwandagalirwa MK, Muwonga J, Keeler C, Emch M, Likwela JL, Tshefu A, Meshnick SR. Low prevalence of Plasmodium malariae and Plasmodium ovale mono-infections among children in the Democratic Republic of the Congo: a population-based, cross-sectional study. Malar J 2016; 15:350. [PMID: 27392905 PMCID: PMC4938993 DOI: 10.1186/s12936-016-1409-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 06/21/2016] [Indexed: 11/10/2022] Open
Abstract
Background In an effort to improve surveillance for epidemiological and clinical outcomes, rapid diagnostic tests (RDTs) have become increasingly widespread as cost-effective and field-ready methods of malaria diagnosis. However, there are concerns that using RDTs specific to Plasmodium falciparum may lead to missed detection of other malaria species such as Plasmodium malariae and Plasmodium ovale. Methods Four hundred and sixty six samples were selected from children under 5 years old in the Democratic Republic of the Congo (DRC) who took part in a Demographic and Health Survey (DHS) in 2013–14. These samples were first tested for all Plasmodium species using an 18S ribosomal RNA-targeted real-time PCR; malaria-positive samples were then tested for P. falciparum, P. malariae and P.ovale using a highly sensitive nested PCR. Results The prevalence of P. falciparum, P. malariae and P. ovale were 46.6, 12.9 and 8.3 %, respectively. Most P. malariae and P. ovale infections were co-infected with P. falciparum—the prevalence of mono-infections of these species were only 1.0 and 0.6 %, respectively. Six out of these eight mono-infections were negative by RDT. The prevalence of P. falciparum by the more sensitive nested PCR was higher than that found previously by real-time PCR. Conclusions Plasmodium malariae and P. ovale remain endemic at a low rate in the DRC, but the risk of missing malarial infections of these species due to falciparum-specific RDT use is low. The observed prevalence of P. falciparum is higher with a more sensitive PCR method. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1409-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Stephanie M Doctor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599-7435, USA
| | - Yunhao Liu
- Department of Statistics and Operations Research, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Olivia G Anderson
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599-7435, USA
| | - Amy N Whitesell
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599-7435, USA
| | - Melchior Kashamuka Mwandagalirwa
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599-7435, USA.,Ecole de Santé Publique, Faculté de Medecine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jérémie Muwonga
- Programme National de Lutte contre le SIDA et les IST, Kinshasa, Democratic Republic of the Congo
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599-7435, USA.,Department of Geography, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Joris L Likwela
- Programme National de Lutte contre le Paludisme, Kinshasa, Democratic Republic of the Congo
| | - Antoinette Tshefu
- Ecole de Santé Publique, Faculté de Medecine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599-7435, USA.
| |
Collapse
|
17
|
Lillehoj H, Kim CH, Kim DK, Keeler C. Comparison of Global Transcriptional Responses of Chicken Following Primary and Secondary Eimeria acervulina Infections (37.13). The Journal of Immunology 2010. [DOI: 10.4049/jimmunol.184.supp.37.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
In this stuy, we compared chicken gene transcriptional profiles following primary and secondary infections with Eimeria acervulina using a 9.6K avian intestinal intraepithelial lymphocyte cDNA microarray (AVIELA). Gene Ontology analysis showed that primary infection significantly modulated the levels of mRNAs for genes involved in the metabolism of lipids and carbohydrates as well as those for innate immune-related genes. By contrast, secondary infection increased the levels of transcripts encoded by genes related to humoral immunity and reduced the levels of transcripts for the innate immune-related genes. Because the observed modulation in transcript levels for gene related to energy metabolism and immunity occurred concurrent with the clinical signs of coccidiosis, these results suggest that altered expression of a specific set of host genes induced by Eimeria infection may be responsible, in part, for the observed reduction in body weight gain and inflammatory gut damage that characterizes avian coccidiosis.
Collapse
Affiliation(s)
- H. Lillehoj
- 1Animal and Natural Resources Institute, Beltsville, MD
| | - Chul-hong Kim
- 1Animal and Natural Resources Institute, Beltsville, MD
| | - Duk Kyung Kim
- 1Animal and Natural Resources Institute, Beltsville, MD
| | | |
Collapse
|
18
|
|
19
|
Abstract
By using spool configurations of a sample containing aluminum foil, in which the axis of the spool is collinear with the RF coil axis, one can obtain high-quality 13C NMR spectra of static samples of organic material attached to the aluminum foil. By combining such a spool configuration (or, alternatively, analogous samples containing equivalent amounts of fine aluminum powder) with the magic-angle hopping (MAH) technique, one can achieve a high degree of isotropic averaging of the 13C spectrum. This opens to NMR techniques the study of a variety of samples containing macroscopic pieces of metal foils, e.g., thin films deposited on metal foils and electrochemical systems with species adsorbed on metal-foil electrodes.
Collapse
Affiliation(s)
- J Xiong
- Department of Chemistry, Colorado State University, Fort Collins, 80523, USA
| | | | | | | | | |
Collapse
|
20
|
Abstract
In this study, regression of the hyaloid vessels has been followed in the tunica vasculosa lentis (TVL) of the Wistar rat using light, transmission and scanning electron microscopy. The investigation extended from the 1st to the 32nd postnatal day. On day one, the posterior tunica vasculosa lentis is made up of radiating capillaries connected by side-arm branches, the vascular walls of which possess a continuous endothelium, a basement membrane and an incomplete pericyte covering. Endothelial cell specialization is apparent in the form of extreme thinning and fenestration in capillary regions lying opposite the lenticular capsule. The earliest detectable regressive changes become apparent on approximately day 3 and initially involve the short connecting capillaries surrounding the posterior pole of the lens and proceed from there. Regression takes place in the presence of rarefaction of vessel wall cells and the accumulation of endothelial cells in the adjacent capillaries. This leads to the formation of acellular channels which are made up of only basement membrane tubes. After the complete disappearance of these transitional acellular channels, the capillary meshwork coarsens. Remnants of these capillaries are detectable until the 30th postnatal day.
Collapse
MESH Headings
- Aging/physiology
- Animals
- Animals, Newborn
- Capillaries/growth & development
- Capillaries/ultrastructure
- Endothelium, Vascular/cytology
- Endothelium, Vascular/growth & development
- Endothelium, Vascular/ultrastructure
- Lens, Crystalline/cytology
- Lens, Crystalline/growth & development
- Lens, Crystalline/ultrastructure
- Microscopy, Electron
- Microscopy, Electron, Scanning
- Muscle Development
- Muscle, Smooth, Vascular/growth & development
- Muscle, Smooth, Vascular/ultrastructure
- Rats
- Rats, Wistar
- Retinal Vessels/growth & development
- Retinal Vessels/ultrastructure
Collapse
Affiliation(s)
- E el-Hifnawi
- Department of Ophthalmology, Medical University of Lübeck, Germany
| | | | | | | |
Collapse
|
21
|
Abstract
Morphological differences between the corneal and palpebral surfaces of the nictitating membrane of the domestic cat were examined using histology, histochemistry and the scanning electron microscope. Both surfaces are covered by one or two layers of epithelial cells. The epithelium contains numerous goblet cells, particularly on the palpebral side. These cells revealed binding sites for six lectins as well as positive PAS reactivity, and alcianophilia at both pH 2.5 and pH 3.5. Numerous lymph follicles located on the corneal side make the epithelium look like lymphoepithelial tissue. Accumulations of lymphatic tissue may also be found on the palpebral side. Scanning electron micrographs showed microvilli on the epithelial surfaces. The function of the cat nictitating membrane is discussed on the basis of our findings and those of other authors. Movements of the nictitating membrane alternate between active and passive phases of gliding. The membrane as a whole effectively protects the nasal portion of the bulb from dust, dehydration and pathogens.
Collapse
Affiliation(s)
- U Schramm
- Institute of Anatomy, Medical University of Lübeck, Germany
| | | | | |
Collapse
|
22
|
Keeler C, McLane C, Covey M, Smith N, Holm K. A review of infection control practices related to intravascular pressure monitoring devices (1975-1985). Heart Lung 1987; 16:201-6. [PMID: 3546208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
23
|
|
24
|
|
25
|
Keeler C. Mosaic cell lines, or leucocyte culturing anomalies? J Hered 1973; 64:167-8. [PMID: 4745490 DOI: 10.1093/oxfordjournals.jhered.a108378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
|
26
|
Bohorfoush JG, Fernandez AR, Keeler C. Mosaic 47(female)XX(X-p) and the Lyon hypothesis. J Hered 1972; 63:381-3. [PMID: 4653437 DOI: 10.1093/oxfordjournals.jhered.a108323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
|
27
|
|
28
|
Keeler C. Finger ridges of Cuna moon-child albinos. J Hered 1972; 63:98-9. [PMID: 5031321 DOI: 10.1093/oxfordjournals.jhered.a108243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
|
29
|
Shatto G, Keeler C. Rehabilitation in San Blas. J Rehabil 1971; 37:10-3. [PMID: 5554368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
|
30
|
|
31
|
|
32
|
|
33
|
|
34
|
|
35
|
|
36
|
|
37
|
Keeler C. Odds and ends of the Moon-child albind study. Dermatol Int 1967; 6:1-10. [PMID: 5591204 DOI: 10.1111/j.1365-4362.1967.tb05225.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
38
|
|
39
|
Keeler C. Cuna moon-child physiognomy. Dermatol Int 1966; 5:12-5. [PMID: 5982459 DOI: 10.1111/j.1365-4362.1966.tb05175.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
40
|
|
41
|
Keeler C. Studies of the Cuna Religion. Science 1962; 135:593. [PMID: 17806683 DOI: 10.1126/science.135.3503.593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
|