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Säve-Söderbergh M, Toljander J, Simonsson M. The complex association between drinking water consumption and endemic gastrointestinal illness as shown by Swedish cohort studies. JOURNAL OF WATER AND HEALTH 2024; 22:1005-1016. [PMID: 38935452 DOI: 10.2166/wh.2024.372] [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: 12/05/2023] [Accepted: 05/06/2024] [Indexed: 06/29/2024]
Abstract
It is well known that municipal drinking water may be the cause of gastrointestinal illness (GII) outbreaks, but it is still unclear to what extent drinking water contributes to endemic GII. To explore this, we conducted a prospective cohort study among 6,955 adults in five municipalities in Sweden, collecting monthly GII episodes and mean daily cold drinking water consumption through SMS (Short Message Service). When the association between drinking water consumption and GII (all symptoms) and acute gastrointestinal illness (AGI, vomiting and/or three loose stools during a 24-h period) were assessed, there were indications that the association departed from linearity, following a unimodal shape. Among consumers in surface water areas, the highest risk of GII and AGI was generally seen among the average consumers, while the opposite was seen among groundwater consumers. The association however also seemed to be affected by neighbouring communities. The results of the study indicate that there is indeed an association between drinking water consumption and endemic GII, but the nature of this association is complex and likely affected by multiple factors, for example, water source type in the home and degree of exposure to drinking water from additional sources.
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Affiliation(s)
- Melle Säve-Söderbergh
- Swedish Food Agency, 751 26 Uppsala, Sweden; Institute of Environmental Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
| | | | - Magnus Simonsson
- Swedish Food Agency, 751 26 Uppsala, Sweden; European Union Reference Laboratory for Foodborne Viruses, Swedish Food Agency, Uppsala 751 26, Sweden
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Ma Y, Kalantari Z, Destouni G. Infectious Disease Sensitivity to Climate and Other Driver-Pressure Changes: Research Effort and Gaps for Lyme Disease and Cryptosporidiosis. GEOHEALTH 2023; 7:e2022GH000760. [PMID: 37303696 PMCID: PMC10251199 DOI: 10.1029/2022gh000760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/13/2023]
Abstract
Climate sensitivity of infectious diseases is discussed in many studies. A quantitative basis for distinguishing and predicting the disease impacts of climate and other environmental and anthropogenic driver-pressure changes, however, is often lacking. To assess research effort and identify possible key gaps that can guide further research, we here apply a scoping review approach to two widespread infectious diseases: Lyme disease (LD) as a vector-borne and cryptosporidiosis as a water-borne disease. Based on the emerging publication data, we further structure and quantitatively assess the driver-pressure foci and interlinkages considered in the published research so far. This shows important research gaps for the roles of rarely investigated water-related and socioeconomic factors for LD, and land-related factors for cryptosporidiosis. For both diseases, the interactions of host and parasite communities with climate and other driver-pressure factors are understudied, as are also important world regions relative to the disease geographies; in particular, Asia and Africa emerge as main geographic gaps for LD and cryptosporidiosis research, respectively. The scoping approach developed and gaps identified in this study should be useful for further assessment and guidance of research on infectious disease sensitivity to climate and other environmental and anthropogenic changes around the world.
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Affiliation(s)
- Y. Ma
- Department of Physical GeographyStockholm UniversityStockholmSweden
| | - Z. Kalantari
- Department of Physical GeographyStockholm UniversityStockholmSweden
- Department of Sustainable DevelopmentEnvironmental Science and Engineering (SEED)KTH Royal Institute of TechnologyStockholmSweden
| | - G. Destouni
- Department of Physical GeographyStockholm UniversityStockholmSweden
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Petterson S, Bradford-Hartke Z, Leask S, Jarvis L, Wall K, Byleveld P. Application of QMRA to prioritise water supplies for Cryptosporidium risk in New South Wales, Australia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 784:147107. [PMID: 34088069 DOI: 10.1016/j.scitotenv.2021.147107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/31/2021] [Accepted: 04/09/2021] [Indexed: 06/12/2023]
Abstract
A Quantitative Microbial Risk Assessment (QMRA) framework was applied to assess 312 drinking water supply systems across regional New South Wales (NSW). The framework was needed to support the implementation of a recommendation in the Australian Drinking Water Guidelines (ADWG) for appropriate treatment barriers to be operating in systems 'at risk' for Cryptosporidium. The objective was to prioritise systems so that those with the highest risk could be identified and addressed first. The framework was developed in a pilot study of 30 systems, selected to represent the range of water supplies across regional NSW. From these, source water categories were defined to represent local conditions with reference to the literature and Cryptosporidium risk factors. Values for Cryptosporidium oocyst concentration were assigned to the categories to allow quantification of the health risk from those water sources. The framework was then used to assess the risks in all 312 regional drinking water supply systems. Combining the disciplined approach of QMRA with simple catchment and treatment information and categorical risk outputs provided a useful and transparent method for prioritising systems for further investigation and potential risk management intervention. The risk rankings for drinking water supplies from this QMRA process have been used to set priorities for a large State Government funding program.
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Affiliation(s)
- S Petterson
- Water& Health Pty Ltd, North Sydney, Australia; School of Medicine, Griffith University, Australia.
| | - Z Bradford-Hartke
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - S Leask
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - L Jarvis
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - K Wall
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - P Byleveld
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
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Tai L, Li J, Yin J, Zhang N, Yang J, Li H, Yang Z, Gong P, Zhang X. A novel detection method of Cryptosporidium parvum infection in cattle based on Cryptosporidium parvum virus 1. Acta Biochim Biophys Sin (Shanghai) 2019; 51:104-111. [PMID: 30544221 DOI: 10.1093/abbs/gmy143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 10/31/2018] [Indexed: 11/15/2022] Open
Abstract
Cryptosporidium parvum is an important zoonotic parasite that causes significant economic loss in the animal husbandry industry, especially the cattle industry. As there is no specific vaccine or drug against Cryptosporidium, a rapid and accurate method for the detection of C. parvum is of great significance. In this study, colloidal gold strips were developed based on Cryptosporidium parvum virus 1 (CSpV1) for the detection of C. parvum infection in cattle fecal samples. The colloidal gold solution was prepared by reducing trisodium citrate and the CSpV1 #5 monoclonal antibody was labeled with colloidal gold. A polyclonal antibody against the CSpV1 capsid protein and an anti-mouse IgG antibody were coated on the colloidal gold strips for use in the test and control lines, respectively. Our results showed that the detection sensitivity in fecal samples was up to a 1:64 dilution. There was no cross-reaction with Cryptosporidium andersoni or Giardia in the fecal samples. The different preservation conditions (room temperature, 4°C, and 37°C) and preservation time (7, 30, 60, and 90 days) were analyzed. The data showed that the strips could be preserved for 90 days at 4°C and for 60 days at room temperature or 37°C. The colloidal gold strips were used to detect the samples of 120 clinical fecal in Changchun, China. The results indicated that the rate of a positive test was 5% (6/120). This study provides a rapid and accurate method for detecting C. parvum infection in cattle and humans.
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Affiliation(s)
- Lixin Tai
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianhua Li
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jigang Yin
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Nan Zhang
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Ju Yang
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - He Li
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zhengtao Yang
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Pengtao Gong
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xichen Zhang
- Key Laboratory of Zoonosis by Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
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McKerr C, O’Brien SJ, Chalmers RM, Vivancos R, Christley RM. Exposures associated with infection with Cryptosporidium in industrialised countries: a systematic review protocol. Syst Rev 2018; 7:70. [PMID: 29720280 PMCID: PMC5932784 DOI: 10.1186/s13643-018-0731-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/13/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cryptosporidium is a protozoan parasite of humans and other animals worldwide and is one of the greatest contributors to human diarrhoeal illness. Transmission can occur indirectly via contaminated food or water, or directly via contact with animals or other infected people. Risk exposures are often identified from outbreak investigations, but a subset of cases remains unexplained, and sources for sporadic disease and pathways to infection are still unclear. Given the few systematic syntheses of reported evidence in industrialised populations, the aim of this review is to consolidate the literature to describe exposures associated with human cryptosporidiosis in industrialised countries, specifically including the UK, and describe any differences between outbreak-associated and sporadic disease. METHODS/DESIGN Where relevant, methods will follow the recommendations made in the Cochrane Handbook for Systematic Reviews of Interventions. Three steps will be used to identify the literature including electronic database searching using PubMed, Scopus, Embase and Web of Science; reference list trawling; and an exploration of the grey literature. Screening of results will be undertaken by two reviewers using pre-defined criteria. Studies conducted in industrialised countries and reporting on human subjects will be included. All observational studies will be included where they report exposures and relevant quantitative results. Data will be extracted using a standardised form. Study quality will be assessed using the ROBINS-I tool. Data will be summarised presenting the papers' main findings including population under study, outcomes, and exposures, and whether these were considered outbreak or sporadic cases. A narrative summary will also be included. Where populations are appropriate, available data will be pooled in a meta-analysis combining the significant exposures across studies. DISCUSSION This review aims to consolidate the evidence for transmission routes and exposures for Cryptosporidium in industrialised countries, with particular reference to how these may apply to the UK. In addition, the review will seek to describe differences between outbreak and sporadic cases. This will help to identify those most vulnerable, highlighting pathways where interventions and public health response may be appropriate. SYSTEMATIC REVIEW REGISTRATION PROSPERO number CRD42017056589 .
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Affiliation(s)
- Caoimhe McKerr
- NIHR Health Protection Research Unit in Gastrointestinal Infections, The University of Liverpool, Liverpool, UK
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, The University of Liverpool, Liverpool, UK
- Institute of Infection and Global Health, University of Liverpool, Waterhouse Building (2nd Floor, Block F), 1-5 Brownlow Street, Liverpool, L69 3GL UK
| | - Sarah J. O’Brien
- NIHR Health Protection Research Unit in Gastrointestinal Infections, The University of Liverpool, Liverpool, UK
| | | | - Roberto Vivancos
- NIHR Health Protection Research Unit in Gastrointestinal Infections, The University of Liverpool, Liverpool, UK
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, The University of Liverpool, Liverpool, UK
- Field Epidemiology Services, Public Health England, Liverpool, UK
| | - Robert M. Christley
- NIHR Health Protection Research Unit in Emerging and Zoonotic Infections, The University of Liverpool, Liverpool, UK
- Institute of Infection and Global Health, University of Liverpool, Waterhouse Building (2nd Floor, Block F), 1-5 Brownlow Street, Liverpool, L69 3GL UK
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Ryan U, Zahedi A, Paparini A. Cryptosporidium in humans and animals-a one health approach to prophylaxis. Parasite Immunol 2017; 38:535-47. [PMID: 27454991 DOI: 10.1111/pim.12350] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 07/05/2016] [Indexed: 01/13/2023]
Abstract
Cryptosporidium is a major cause of moderate-to-severe diarrhoea in humans worldwide, second only to rotavirus. Due to the wide host range and environmental persistence of this parasite, cryptosporidiosis can be zoonotic and associated with foodborne and waterborne outbreaks. Currently, 31 species are recognized as valid, and of these, Cryptosporidium hominis and Cryptosporidium parvum are responsible for the majority of infections in humans. The immune status of the host, both innate and adaptive immunity, has a major impact on the severity of the disease and its prognosis. Immunocompetent individuals typically experience self-limiting diarrhoea and transient gastroenteritis lasting up to 2 weeks and recover without treatment, suggesting an efficient host antiparasite immune response. Immunocompromised individuals can suffer from intractable diarrhoea, which can be fatal. Effective drug treatments and vaccines are not yet available. As a result of this, the close cooperation and interaction between veterinarians, health physicians, environmental managers and public health operators is essential to properly control this disease. This review focuses on a One Health approach to prophylaxis, including the importance of understanding transmission routes for zoonotic Cryptosporidium species, improved sanitation and better risk management, improved detection, diagnosis and treatment and the prospect of an effective anticryptosporidial vaccine.
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Affiliation(s)
- U Ryan
- School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia.
| | - A Zahedi
- School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
| | - A Paparini
- School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
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Bylund J, Toljander J, Lysén M, Rasti N, Engqvist J, Simonsson M. Measuring sporadic gastrointestinal illness associated with drinking water - an overview of methodologies. JOURNAL OF WATER AND HEALTH 2017; 15:321-340. [PMID: 28598337 DOI: 10.2166/wh.2017.261] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
There is an increasing awareness that drinking water contributes to sporadic gastrointestinal illness (GI) in high income countries of the northern hemisphere. A literature search was conducted in order to review: (1) methods used for investigating the effects of public drinking water on GI; (2) evidence of possible dose-response relationship between sporadic GI and drinking water consumption; and (3) association between sporadic GI and factors affecting drinking water quality. Seventy-four articles were selected, key findings and information gaps were identified. In-home intervention studies have only been conducted in areas using surface water sources and intervention studies in communities supplied by ground water are therefore needed. Community-wide intervention studies may constitute a cost-effective alternative to in-home intervention studies. Proxy data that correlate with GI in the community can be used for detecting changes in the incidence of GI. Proxy data can, however, not be used for measuring the prevalence of illness. Local conditions affecting water safety may vary greatly, making direct comparisons between studies difficult unless sufficient knowledge about these conditions is acquired. Drinking water in high-income countries contributes to endemic levels of GI and there are public health benefits for further improvements of drinking water safety.
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Affiliation(s)
- John Bylund
- National Food Agency, Box 622, Uppsala SE-751 26, Sweden E-mail:
| | - Jonas Toljander
- National Food Agency, Box 622, Uppsala SE-751 26, Sweden E-mail:
| | - Maria Lysén
- National Food Agency, Box 622, Uppsala SE-751 26, Sweden E-mail:
| | - Niloofar Rasti
- National Food Agency, Box 622, Uppsala SE-751 26, Sweden E-mail:
| | - Jannes Engqvist
- National Food Agency, Box 622, Uppsala SE-751 26, Sweden E-mail:
| | - Magnus Simonsson
- National Food Agency, Box 622, Uppsala SE-751 26, Sweden E-mail:
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8
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Cryptosporidium genotypes and associated risk factors in a cohort of Egyptian children. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s00580-017-2477-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Human cryptosporidiosis in Iran: a systematic review and meta-analysis. Parasitol Res 2017; 116:1111-1128. [PMID: 28110441 DOI: 10.1007/s00436-017-5376-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 01/12/2017] [Indexed: 01/20/2023]
Abstract
Cryptosporidiosis caused by Cryptosporidium spp. is an important parasitic disease that can be life-threatening for children and immunocompromised patients. This systematic review and meta-analysis was designed to determine the prevalence rate of Cryptosporidium infection and related risk factors among the Iranian general population. We searched electronic databases including Google Scholar, PubMed, Science Direct, Scopus and Proquest for articles in English and SID, Magiran, IranMedex, and IranDoc for articles in Persian. Out of 4816 studies identified in the electronic search, 94 articles were eligible for inclusion in the systematic review and meta-analysis. The prevalence rate of cryptosporidiosis by using the random effect model among children, healthy people, and gastroenteritis and immunocompromised patients in Iran was estimated as 3.65, 2.94, 1.29, and 4.54%, respectively. Findings of a phylogenetic analysis inferred by gp60 and 18S ribosomal RNA markers indicated that most of the infection rate belonged to C. parvum (particularly subtype IIaA15G2R1) and C. hominis among understudied groups. The present study is the first systematic review and meta-analysis providing a comprehensive view of the prevalence of human cryptosporidiosis and its related risk factors in Iran. It seems that the awareness of Cryptosporidium prevalence, risk factors, and disease complications may be required for developing effective strategies to prevent infection.
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Paoletti B, Traversa D, Iorio R, De Berardinis A, Bartolini R, Salini R, Di Cesare A. Zoonotic parasites in feces and fur of stray and private dogs from Italy. Parasitol Res 2015; 114:2135-41. [DOI: 10.1007/s00436-015-4402-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 02/27/2015] [Indexed: 12/21/2022]
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Ramsay CN, Wagner AP, Robertson C, Smith HV, Pollock KGJ. Effects of drinking-water filtration on Cryptosporidium seroepidemiology, Scotland. Emerg Infect Dis 2014; 20:70-6. [PMID: 24377436 PMCID: PMC3884704 DOI: 10.3201/eid2001.120386] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Improved filtration is associated with reduced prevalence of antibodies against Cryptosporidium spp. Continuous exposure to low levels of Cryptosporidium oocysts is associated with production of protective antibodies. We investigated prevalence of antibodies against the 27-kDa Cryptosporidium oocyst antigen among blood donors in 2 areas of Scotland supplied by drinking water from different sources with different filtration standards: Glasgow (not filtered) and Dundee (filtered). During 2006–2009, seroprevalence and risk factor data were collected; this period includes 2007, when enhanced filtration was introduced to the Glasgow supply. A serologic response to the 27-kDa antigen was found for ≈75% of donors in the 2 cohorts combined. Mixed regression modeling indicated a 32% step-change reduction in seroprevalence of antibodies against Cryptosporidium among persons in the Glasgow area, which was associated with introduction of enhanced filtration treatment. Removal of Cryptosporidium oocysts from water reduces the risk for waterborne exposure, sporadic infections, and outbreaks. Paradoxically, however, oocyst removal might lower immunity and increase the risk for infection from other sources.
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Cryptosporidiumspecies in humans and animals: current understanding and research needs. Parasitology 2014; 141:1667-85. [DOI: 10.1017/s0031182014001085] [Citation(s) in RCA: 402] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYCryptosporidiumis increasingly recognized as one of the major causes of moderate to severe diarrhoea in developing countries. With treatment options limited, control relies on knowledge of the biology and transmission of the members of the genus responsible for disease. Currently, 26 species are recognized as valid on the basis of morphological, biological and molecular data. Of the nearly 20Cryptosporidiumspecies and genotypes that have been reported in humans,Cryptosporidium hominisandCryptosporidium parvumare responsible for the majority of infections. Livestock, particularly cattle, are one of the most important reservoirs of zoonotic infections. Domesticated and wild animals can each be infected with severalCryptosporidiumspecies or genotypes that have only a narrow host range and therefore have no major public health significance. Recent advances in next-generation sequencing techniques will significantly improve our understanding of the taxonomy and transmission ofCryptosporidiumspecies, and the investigation of outbreaks and monitoring of emerging and virulent subtypes. Important research gaps remain including a lack of subtyping tools for manyCryptosporidiumspecies of public and veterinary health importance, and poor understanding of the genetic determinants of host specificity ofCryptosporidiumspecies and impact of climate change on the transmission ofCryptosporidium.
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POLLOCK KGJ, YOUNG D, ROBERTSON C, AHMED S, RAMSAY CN. Reduction in cryptosporidiosis associated with introduction of enhanced filtration of drinking water at Loch Katrine, Scotland. Epidemiol Infect 2014; 142:56-62. [PMID: 23591075 PMCID: PMC9152614 DOI: 10.1017/s0950268813000678] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 02/25/2013] [Accepted: 02/27/2013] [Indexed: 11/06/2022] Open
Abstract
Previous evidence has suggested an association between cryptosporidiosis and consumption of unfiltered drinking water from Loch Katrine in Scotland. Before September 2007, the water was only micro-strained and chlorinated; however, since that time, coagulation and rapid gravity filtration have been installed. In order to determine risk factors associated with cryptosporidiosis, including drinking water, we analysed data on microbiologically confirmed cases of cryptosporidiosis from 2004 to 2010. We identified an association between the incidence of cryptosporidiosis and unfiltered Loch Katrine drinking water supplied to the home (odds ratio 1.86, 95% confidence interval 1.11-3.11, P = 0.019). However, while filtration appears to be associated with initially reduced rates of cryptosporidiosis, evidence suggests it may paradoxically make those consumers more susceptible to other transmission routes in the long-term. These findings support implementation of similar treatment for other unfiltered drinking-water supplies, as a means of reducing cryptosporidiosis associated with drinking water.
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Affiliation(s)
- K. G. J. POLLOCK
- Health Protection Scotland, Clifton House, Clifton Place, Glasgow, UK
| | - D. YOUNG
- Statistics Department, University of Strathclyde, Glasgow, UK
| | - C. ROBERTSON
- Statistics Department, University of Strathclyde, Glasgow, UK
| | - S. AHMED
- NHS Greater Glasgow & Clyde Health Board, Glasgow, UK
| | - C. N. RAMSAY
- Health Protection Scotland, Clifton House, Clifton Place, Glasgow, UK
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Rahmouni I, Essid R, Aoun K, Bouratbine A. Glycoprotein 60 diversity in Cryptosporidium parvum causing human and cattle cryptosporidiosis in the rural region of Northern Tunisia. Am J Trop Med Hyg 2013; 90:346-50. [PMID: 24343888 DOI: 10.4269/ajtmh.13-0522] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The zoonotic potential of Cryptosporidium parvum was studied in an extensive cattle farming region of northern Tunisia. Seventy fecal samples from pre-weaning calves and 403 fecal samples from children were examined by microscopy after modified Ziehl-Neelsen (MZN) staining. Positive Cryptosporidium specimens were identified at a species level using an 18S rRNA nested polymerase chain reaction (PCR) followed by an Restriction Fragment Length Polymorphism (RFLP) analysis. C. parvum isolates were subgenotyped by sequence analysis of the glycoprotein 60 (gp60) gene. Among calf samples, 14 samples were positive by MZN method. C. parvum was identified in all cases. Twelve parvum isolates (85.7%) belonged to family subtype IIa. Subtype IIaA15G2R1 was more prevalent (50%). Two C. parvum isolates corresponded to the IIdA16G1 subtype. Seven human samples were positive by MZN method. C. parvum and C. meleagridis were identified in four and three cases, respectively. Intraspecific characterization of C. parvum identified two subtypes, the IIaA15G2R1 and the IIdA16G1, also found in calves.
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Affiliation(s)
- Ikram Rahmouni
- Laboratoire de Parasitologie-Mycologie, Institut Pasteur de Tunis, Tunis, Tunisia
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Abstract
Cryptosporidium is a protozoan parasite of medical and veterinary importance that causes gastroenteritis in a variety of vertebrate hosts. Several studies have reported different degrees of pathogenicity and virulence among Cryptosporidium species and isolates of the same species as well as evidence of variation in host susceptibility to infection. The identification and validation of Cryptosporidium virulence factors have been hindered by the renowned difficulties pertaining to the in vitro culture and genetic manipulation of this parasite. Nevertheless, substantial progress has been made in identifying putative virulence factors for Cryptosporidium. This progress has been accelerated since the publication of the Cryptosporidium parvum and C. hominis genomes, with the characterization of over 25 putative virulence factors identified by using a variety of immunological and molecular techniques and which are proposed to be involved in aspects of host-pathogen interactions from adhesion and locomotion to invasion and proliferation. Progress has also been made in the contribution of host factors that are associated with variations in both the severity and risk of infection. Here we provide a review comprised of the current state of knowledge on Cryptosporidium infectivity, pathogenesis, and transmissibility in light of our contemporary understanding of microbial virulence.
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Global occurrence of Cryptosporidium and Giardia in shellfish: Should Canada take a closer look? Food Res Int 2013. [DOI: 10.1016/j.foodres.2013.02.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Sarkar R, Ajjampur SSR, Prabakaran AD, Geetha JC, Sowmyanarayanan TV, Kane A, Duara J, Muliyil J, Balraj V, Naumova EN, Ward H, Kang G. Cryptosporidiosis among children in an endemic semiurban community in southern India: does a protected drinking water source decrease infection? Clin Infect Dis 2013; 57:398-406. [PMID: 23709650 DOI: 10.1093/cid/cit288] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND A quasi-experimental study was conducted to determine whether or not a protected water supply (bottled drinking water) could prevent or delay cryptosporidial infections among children residing in an endemic community. METHODS A total of 176 children residing in a semiurban slum area in southern India were enrolled preweaning and received either bottled (n = 90) or municipal (n = 86) drinking water based on residence in specific streets. Weekly surveillance visits were conducted until children reached their second birthday. Stool samples were collected every month and during diarrheal episodes, and were tested for the presence of Cryptosporidium species by polymerase chain reaction. Differences in the incidence of cryptosporidiosis between bottled and municipal water groups were compared using Poisson survival models, and a propensity score model was developed to adjust for the effect of potential confounders. RESULTS A total of 186 episodes of cryptosporidiosis, mostly asymptomatic, were observed in 118 (67%) children during the follow-up period at a rate of 0.59 episodes per child-year. Diarrhea associated with Cryptosporidium species tended to be longer in duration and more severe. Stunting at 6 months was associated with a higher risk of cryptosporidiosis (rate ratio [RR] = 1.40; 95% confidence interval [CI], 1.03-1.91). A higher gastrointestinal disease burden was also seen in children with cryptosporidiosis. Drinking bottled water was not associated with a reduced risk of cryptosporidiosis (adjusted RR = 0.86; 95% CI, .60-1.23). CONCLUSIONS This study documented a high burden of cryptosporidiosis among children in an endemic Indian slum community. The lack of association between drinking bottled water and cryptosporidiosis suggests possible spread from asymptomatically infected individuals involving multiple transmission pathways.
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Affiliation(s)
- Rajiv Sarkar
- Department of Gastrointestinal Sciences, Christian Medical College, Vellore, Tamil Nadu, India
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Subclinical infection and asymptomatic carriage of gastrointestinal zoonoses: occupational exposure, environmental pathways, and the anonymous spread of disease. Epidemiol Infect 2013; 141:2011-21. [PMID: 23659675 DOI: 10.1017/s0950268813001131] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Asymptomatic carriage of gastrointestinal zoonoses is more common in people whose profession involves them working directly with domesticated animals. Subclinical infections (defined as an infection in which symptoms are either asymptomatic or sufficiently mild to escape diagnosis) are important within a community as unknowing (asymptomatic) carriers of pathogens do not change their behaviour to prevent the spread of disease; therefore the public health significance of asymptomatic human excretion of zoonoses should not be underestimated. However, optimal strategies for managing diseases where asymptomatic carriage instigates further infection remain unresolved, and the impact on disease management is unclear. In this review we consider the environmental pathways associated with prolonged antigenic exposure and critically assess the significance of asymptomatic carriage in disease outbreaks. Although screening high-risk groups for occupationally acquired diseases would be logistically problematical, there may be an economic case for identifying and treating asymptomatic carriage if the costs of screening and treatment are less than the costs of identifying and treating those individuals infected by asymptomatic hosts.
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Abstract
Cryptosporidium is an important enteric parasite that is transmitted via the fecal-oral route, water and food. Humans, wildlife and domestic livestock all potentially contribute Cryptosporidium to surface waters. Most species of Cryptosporidium are morphologically indistinguishable and can only be identified using molecular tools. Over 24 species have been identified and of these, 7 Cryptosporidium species/genotypes are responsible for most human cryptosporidiosis cases. In Australia, relatively few genotyping studies have been conducted. Six Cryptosporidium species (C. hominis, C. parvum, C. meleagridis, C. fayeri, C. andersoni and C. bovis) have been identified in humans in Australia. However, little is known about the contribution of animal hosts to human pathogenic strains of Cryptosporidium in drinking water catchments. In this review, we focus on the available genotyping data for native, feral and domestic animals inhabiting drinking water catchments in Australia to provide an improved understanding of the public health implications and to identify key research gaps.
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Austin Z, Alcock RE, Christley RM, Haygarth PM, Heathwaite AL, Latham SM, Mort M, Oliver DM, Pickup R, Wastling JM, Wynne B. Policy, practice and decision making for zoonotic disease management: water and Cryptosporidium. ENVIRONMENT INTERNATIONAL 2012; 40:70-78. [PMID: 22280930 DOI: 10.1016/j.envint.2011.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 11/15/2011] [Accepted: 11/17/2011] [Indexed: 05/31/2023]
Abstract
Decision making for zoonotic disease management should be based on many forms of appropriate data and sources of evidence. However, the criteria and timing for policy response and the resulting management decisions are often altered when a disease outbreak occurs and captures full media attention. In the case of waterborne disease, such as the robust protozoa, Cryptosporidium spp, exposure can cause significant human health risks and preventing exposure by maintaining high standards of biological and chemical water quality remains a priority for water companies in the UK. Little has been documented on how knowledge and information is translated between the many stakeholders involved in the management of Cryptosporidium, which is surprising given the different drivers that have shaped management decisions. Such information, coupled with the uncertainties that surround these data is essential for improving future management strategies that minimise disease outbreaks. Here, we examine the interplay between scientific information, the media, and emergent government and company policies to examine these issues using qualitative and quantitative data relating to Cryptosporidium management decisions by a water company in the North West of England. Our results show that political and media influences are powerful drivers of management decisions if fuelled by high profile outbreaks. Furthermore, the strength of the scientific evidence is often constrained by uncertainties in the data, and in the way knowledge is translated between policy levels during established risk management procedures. In particular, under or over-estimating risk during risk assessment procedures together with uncertainty regarding risk factors within the wider environment, was found to restrict the knowledge-base for decision-making in Cryptosporidium management. Our findings highlight some key current and future challenges facing the management of such diseases that are widely applicable to other risk management situations.
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Affiliation(s)
- Zoë Austin
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK.
| | - Ruth E Alcock
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK
| | - Robert M Christley
- National Centre for Zoonosis Research, University of Liverpool Veterinary School, Leahurst, Chester High Road, Neston, Wirral CH64 7TE, UK; Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Philip M Haygarth
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK
| | | | - Sophia M Latham
- National Centre for Zoonosis Research, University of Liverpool Veterinary School, Leahurst, Chester High Road, Neston, Wirral CH64 7TE, UK; Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Maggie Mort
- Department of Sociology and School of Medicine, Lancaster University, Lancaster, LA1 4YT, UK
| | - David M Oliver
- Biological & Environmental Sciences, School of Natural Sciences, University of Stirling, Stirling, FK9 4LA, Scotland, UK
| | - Roger Pickup
- Biomedical and Life Sciences Division, Faculty of Health and Medicine, Lancaster University, LA1 4YQ, UK
| | - Jonathan M Wastling
- Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Brian Wynne
- ESRC Centre for Economic and Social Aspects of Genomics, Cesagen, Lancaster University, LA1 4YD, UK
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Ng JSY, Eastwood K, Walker B, Durrheim DN, Massey PD, Porigneaux P, Kemp R, McKinnon B, Laurie K, Miller D, Bramley E, Ryan U. Evidence of Cryptosporidium transmission between cattle and humans in northern New South Wales. Exp Parasitol 2012; 130:437-41. [PMID: 22333036 DOI: 10.1016/j.exppara.2012.01.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 01/10/2012] [Accepted: 01/18/2012] [Indexed: 11/16/2022]
Abstract
Cryptosporidium is an enteric parasite of public health significance that causes diarrhoeal illness through faecal oral contamination and via water. Zoonotic transmission is difficult to determine as most species of Cryptosporidium are morphologically identical and can only be differentiated by molecular means. Transmission dynamics of Cryptosporidium in rural populations were investigated through the collection of 196 faecal samples from diarrheic (scouring) calves on 20 farms and 63 faecal samples from humans on 14 of these farms. The overall prevalence of Cryptosporidium in cattle and humans by PCR and sequence analysis of the 18S rRNA was 73.5% (144/196) and 23.8% (15/63), respectively. Three species were identified in cattle; Cryptosporidium parvum, Cryptosporidium bovis and Cryptosporidium ryanae, and from humans, C. parvum and C. bovis. This is only the second report of C. bovis in humans. Subtype analysis at the gp60 locus identified C. parvum subtype IIaA18G3R1 as the most common subtype in calves. Of the seven human C. parvum isolates successfully subtyped, five were IIaA18G3R1, one was IIdA18G2 and one isolate had a mix of IIaA18G3R1 and IIdA19G2. These findings suggest that zoonotic transmission may have occurred but more studies involving extensive sampling of both calves and farm workers are needed for a better understanding of the sources of Cryptosporidium infections in humans from rural areas of Australia.
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Affiliation(s)
- Josephine Su Yin Ng
- School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA 6150, Australia
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Heidarnegadi SM, Mohebali M, Maraghi SH, Babaei Z, Farnia SH, Bairami A, Rezaeian M. Cryptosporidium spp. Infection in human and domestic animals. IRANIAN JOURNAL OF PARASITOLOGY 2012; 7:53-8. [PMID: 23133472 PMCID: PMC3488821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 12/19/2011] [Indexed: 11/01/2022]
Abstract
BACKGROUND Cryptosporidium spp. is a coccidian parasite infected humans and animals. Prevalence rate of Cryptosporidium spp. infection associated with is some parameters such as sampling, age, season, country and contact to domestic animals. This study aimed to determine Cryptosporidium spp. Infection in humans and some animals in rural areas of Shushtar district from Khuzestan Province, south- west of Iran. METHODS In this study, Stool specimens were randomly collected from 45 cattle, 8 buffalos, 35 calves, 22 turkeys, 3 sheep, 2 geese as well as 62 humans in different seasons selected from rural areas of Shushtar district located in Khuzestan in the south- west of Iran from August 2009 to April 2011. The collected stool samples were examined by modified Ziehl-Neelsen staining method. RESULTS Altogether, 68/115 (59.1%) domestic animals and 9/62 (14.5%) of humans were showed Cryptosporidium spp. infection in the study areas. CONCLUSION In this study we found the high frequency of Cryptosporidium spp. infection in the studied areas.
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Affiliation(s)
- SM Heidarnegadi
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran
| | - M Mohebali
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran,Center for Research of Endemic Parasites of Iran (CREPI), Tehran University of Medical Sciences, Tehran, Iran
| | - SH Maraghi
- Dept. of Medical Parasitology and Mycology, School of Medical, Jundishapur University of Medical Sciences, Ahwaz, Iran
| | - Z Babaei
- Dept. of Medical Parasitology and Mycology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - SH Farnia
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran
| | - A Bairami
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran
| | - M Rezaeian
- Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran,Center for Research of Endemic Parasites of Iran (CREPI), Tehran University of Medical Sciences, Tehran, Iran,Corresponding author:Tel: +98 21 88951392, E-mail:
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Longitudinal investigation of protozoan parasites in meat lamb farms in southern Western Australia. Prev Vet Med 2011; 101:192-203. [DOI: 10.1016/j.prevetmed.2011.05.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 04/13/2011] [Accepted: 05/28/2011] [Indexed: 11/19/2022]
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The epidemiology of sporadic human infections with unusual cryptosporidia detected during routine typing in England and Wales, 2000-2008. Epidemiol Infect 2011; 140:673-83. [PMID: 21733255 DOI: 10.1017/s0950268811000860] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Routine typing of 14 469 isolates from human cryptosporidiosis cases between 2000 and 2008 revealed that 7439 (51·4%) were Cryptosporidium (C.) hominis, 6372 (44·0%) C. parvum, 51 (0·4%) both C. hominis and C. parvum, 443 (3·1%) were not typable and 164 (1·1%) were other Cryptosporidium species or genotypes. Of the latter, 109 were C. meleagridis, 38 C. felis, 11 C. ubiquitum, one C. canis, two horse, two novel and one skunk genotype. C. hominis monkey genotype and C. cuniculus were identified in a separate study. Patients with unusual infections were older than those with C. hominis (P<0·01) or C. parvum (P<0·01) and were more likely to be immunocompromised (Fisher's exact P<0·01). Forty-one percent of unusual cases had travelled abroad, mainly to the Indian subcontinent. Significant risk factors in those with unusual species were travel abroad (C. meleagridis, P<0·01), being immunocompromised (C. felis, Fisher's exact P=0·02), and contact with cats (C. felis, Fisher's exact P=0·02).
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Tang J, McDonald S, Peng X, Samadder SR, Murphy TM, Holden NM. Modelling Cryptosporidium oocysts transport in small ungauged agricultural catchments. WATER RESEARCH 2011; 45:3665-3680. [PMID: 21555142 DOI: 10.1016/j.watres.2011.04.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 04/06/2011] [Accepted: 04/07/2011] [Indexed: 05/30/2023]
Abstract
Cryptosporidium is an environmentally robust pathogen that has caused severe waterborne disease outbreaks worldwide. The main source of zoonotic Cryptosporidium parvum oocysts in human drinking water is likely to be from farm animals via catchment pathways with water as the main transport vector. The vast majority of small agricultural catchments are ungauged therefore it is difficult to use a process model to predict and understand the mechanisms and activities that regulate the risk of surface water contamination from agricultural areas. For this study, two ungauged agricultural catchments in Ireland were used to model Cryptosporidium oocyst transport using SWAT2005 on a daily basis with reference data from adjacent catchment gauging stations. The results indicated that SWAT2005 could simulate stream flow with good agreement between prediction and observation on a monthly basis (R(2) from 0.94 to 0.83 and E (efficiency) from 0.92 to 0.66), but Cryptosporidium oocyst concentration results were less reliable (R(2) from 0.20 to 0.37, P < 0.05; with poor E -0.37 to -2.57). A sensitivity analysis using independent parameter perturbation indicated that temperature was the most important parameter regulating oocyst transport in the study catchments and that the timing of manure application relative to the occurrence of water runoff event was critical. The results also showed that grazing management had little influence on predicted oocyst transport while fields fertilized with manure were the key critical source areas for microbial contaminations in the study catchments. It was concluded that the approach presented could be used to assist with understanding the epidemiology of waterborne cryptosporidiosis outbreaks and to improve catchment management for the safety of the general public health.
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Affiliation(s)
- Jialiang Tang
- UCD Bioresources Research Centre/Biosystems Engineering, School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
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Pollock KGJ, Ternent HE, Mellor DJ, Chalmers RM, Smith HV, Ramsay CN, Innocent GT. Spatial and temporal epidemiology of sporadic human cryptosporidiosis in Scotland. Zoonoses Public Health 2011; 57:487-92. [PMID: 19638164 DOI: 10.1111/j.1863-2378.2009.01247.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The spatial and temporal epidemiology of human cryptosporidiosis was described by analysing sporadic cases reported in Scotland from 2005 to 2007. Measures of livestock density and human population density were explored as indicators of the geographical variation in prevalence. Cryptosporidium parvum was more common in areas with lower human population densities, with a higher ratio of the number of farms to human inhabitants and with a higher ratio of the number of private water supplies to human inhabitants. Cryptosporidium parvum caused disease in humans in rural areas and in areas with high ruminant livestock density, whereas Cryptosporidium hominis was more common in the more densely human populated areas of Scotland. The association of private water supplies and increased Cryptosporidium reports merits further public health efforts.
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Ng J, Yang R, McCarthy S, Gordon C, Hijjawi N, Ryan U. Molecular characterization of Cryptosporidium and Giardia in pre-weaned calves in Western Australia and New South Wales. Vet Parasitol 2011; 176:145-50. [DOI: 10.1016/j.vetpar.2010.10.056] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 10/28/2010] [Accepted: 10/29/2010] [Indexed: 11/28/2022]
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Hussein AS. Cryptosporidium parvum causes gastroenteritis epidemics in the Nablus region of Palestine. Trop Med Int Health 2010; 16:12-7. [PMID: 21129132 DOI: 10.1111/j.1365-3156.2010.02673.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A total of 30 faecal samples collected from individuals admitted to a local hospital in Nablus city in Palestine with gastroenteritis symptoms, plus five faecal samples from healthy individuals living in the same area were screened for the presence of Cryptosporidium spp. by microscopic analysis using malachite green negative staining. Molecular techniques were used to confirm the microscopic identification. All 30 samples from individuals with gastroenteritis symptoms were positive by both techniques. No other parasites were found in the faecal material of patients or healthy individuals. To explore the source of the outbreak, water was collected from various reservoirs and springs that supply the city with drinking water. Al-Qaryoon water spring was found to be contaminated with Cryptosporidium using both microscopic and molecular analysis. No other water resources were found to be contaminated. Genotyping analysis of Cryptosporidium oocysts using PCR-RFLP technique identified the parasite as C. parvum.
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Affiliation(s)
- Ayman S Hussein
- Faculty of Medicine, Genetics Laboratory, An-Najah National University, Nablus, Palestine.
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31
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Putignani L, Menichella D. Global distribution, public health and clinical impact of the protozoan pathogen cryptosporidium. Interdiscip Perspect Infect Dis 2010; 2010:753512. [PMID: 20706669 PMCID: PMC2913630 DOI: 10.1155/2010/753512] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 01/07/2010] [Accepted: 05/11/2010] [Indexed: 12/19/2022] Open
Abstract
Cryptosporidium spp. are coccidians, oocysts-forming apicomplexan protozoa, which complete their life cycle both in humans and animals, through zoonotic and anthroponotic transmission, causing cryptosporidiosis. The global burden of this disease is still underascertained, due to a conundrum transmission modality, only partially unveiled, and on a plethora of detection systems still inadequate or only partially applied for worldwide surveillance. In children, cryptosporidiosis encumber is even less recorded and often misidentified due to physiological reasons such as early-age unpaired immunological response. Furthermore, malnutrition in underdeveloped countries or clinical underestimation of protozoan etiology in developed countries contribute to the underestimation of the worldwide burden. Principal key indicators of the parasite distribution were associated to environmental (e.g., geographic and temporal clusters, etc.) and host determinants of the infection (e.g., age, immunological status, travels, community behaviours). The distribution was geographically mapped to provide an updated picture of the global parasite ecosystems. The present paper aims to provide, by a critical analysis of existing literature, a link between observational epidemiological records and new insights on public health, and diagnostic and clinical impact of cryptosporidiosis.
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Affiliation(s)
- Lorenza Putignani
- Microbiology Unit, Bambino Gesù Pediatric Hospital, Scientific Institute, Piazza Sant'Onofrio 4, 00165 Rome, Italy
| | - Donato Menichella
- Microbiology Unit, Bambino Gesù Pediatric Hospital, Scientific Institute, Piazza Sant'Onofrio 4, 00165 Rome, Italy
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Chako CZ, Tyler JW, Schultz LG, Chiguma L, Beerntsen BT. Cryptosporidiosis in people: it's not just about the cows. J Vet Intern Med 2010; 24:37-43. [PMID: 20041989 DOI: 10.1111/j.1939-1676.2009.0431.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Cryptosporidiosis is one of the most common causes of infectious diarrhea in people. Although dairy calves are high-risk hosts, the role of other livestock, pets, and humans in the disease should not be underestimated. Some Cryptosporidium species and strains are specific to people, others are specific to animals while some are zoonotic pathogens. Cryptosporidium hominis is the species responsible for the majority of human cases in the United States, Sub-Saharan Africa, and Asia, while Cryptosporidium parvum accounts for more human cases in Europe and particularly in the United Kingdom. A deeper understanding of Cryptosporidium host range, reservoirs, and transmission is needed to develop preventive strategies to protect the general public.
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Affiliation(s)
- C Z Chako
- University of Missouri Public Health Program, Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, 213 Connaway Hall, Columbia, MO 65211, USA
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Ng J, MacKenzie B, Ryan U. Longitudinal multi-locus molecular characterisation of sporadic Australian human clinical cases of cryptosporidiosis from 2005 to 2008. Exp Parasitol 2010; 125:348-56. [PMID: 20206624 DOI: 10.1016/j.exppara.2010.02.017] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 02/26/2010] [Accepted: 02/26/2010] [Indexed: 11/27/2022]
Abstract
Cryptosporidium is a gastrointestinal parasite that is recognised as a significant cause of non-viral diarrhea in both developing and industrialised countries. In the present study, a longitudinal analysis of 248 faecal specimens from Australian humans with gastrointestinal symptoms from 2005 to 2008 was conducted. Sequence analysis of the 18S rRNA gene locus and the 60kDa glycoprotein (gp60) gene locus revealed that 195 (78.6%) of the cases were due to infection with Cryptosporidium hominis, 49 (19.8%) with Cryptosporidium parvum and four (1.6%) with Cryptosporidium meleagridis. A total of eight gp60 subtype families were identified; five C. hominis subtype families (Ib, Id, Ie, If and Ig), and two C. parvum subtype families (IIa and IId). The Id subtype family was the most common C. hominis subtype family identified in 45.7% of isolates, followed by the Ig subtype family (30.3%) and the Ib subtype family (20%). The most common C. parvum subtype was IIaA18G3R1, identified in 65.3% of isolates. The more rare zoonotic IId A15G1 subtype was identified in one isolate. Statistical analysis showed that the Id subtype was associated with abdominal pain (p<0.05) and that in sporadic cryptosporidiosis, children aged 5 and below were 1.91 times and 1.88 times more likely to be infected with subtype Id (RR 1.91; 95% CI, 1.7-2.89; p<0.05) and Ig (RR 1.88; 95% CI, 1.10-3.24; p<0.05) compared to children aged 5 and above. A subset of isolates were also analysed at the variable CP47 and MSC6-7 gene loci. Findings from this study suggest that anthroponotic transmission of Cryptosporidium plays a major role in the epidemiology of cryptosporidiosis in Western Australian humans.
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Affiliation(s)
- Josephine Ng
- Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA 6150, Australia
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Yoder JS, Beach MJ. Cryptosporidium surveillance and risk factors in the United States. Exp Parasitol 2009; 124:31-9. [PMID: 19786022 DOI: 10.1016/j.exppara.2009.09.020] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 07/08/2009] [Accepted: 09/18/2009] [Indexed: 10/20/2022]
Abstract
Surveillance for Cryptosporidium in the United States indicates that the reported incidence of infection has increased dramatically since 2004. The reasons for this increase are unclear but might be caused by an actual increase in incidence, improved surveillance, improved awareness about cryptosporidiosis, and/or increases in testing practices resulting from the licensing of the first-ever treatment for cryptosporidiosis. While regional differences remain, the incidence of cryptosporidiosis appears to be increasing across the United States. Onset of illness is most common during the summer, particularly among younger children. Cryptosporidiosis case reporting also influences outbreak detection and reporting; the recent rise in cases coincides with an increase in the number of reported cryptosporidiosis outbreaks, particularly in treated recreational water venues. Risk factors include ingesting contaminated recreational or drinking water, exposure to infected animals, having close contacts with cryptosporidiosis, travel to disease-endemic areas, and ingestion of contaminated food. Advances in molecular characterization of clinical specimens have improved our understanding of the changing epidemiology and risk factors. Prevention and control of cryptosporidiosis requires continued efforts to interrupt the transmission of Cryptosporidium through water, food, and contact with infected persons or animals. Of particular importance is continued improvement and monitoring of drinking water treatment and advances in the design, operation, and management of recreational water venues coupled with behavioral changes among the swimming public.
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Affiliation(s)
- Jonathan S Yoder
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Department of Health and Human Services, Atlanta, GA, USA.
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Thompson RCA, Olson ME, Zhu G, Enomoto S, Abrahamsen MS, Hijjawi NS. Cryptosporidium and cryptosporidiosis. ADVANCES IN PARASITOLOGY 2009; 59:77-158. [PMID: 16182865 DOI: 10.1016/s0065-308x(05)59002-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Cryptosporidium is one of the most common enteric protozoan parasites of vertebrates with a wide host range that includes humans and domestic animals. It is a significant cause of diarrhoeal disease and an ubiquitous contaminant of water which serves as an excellent vehicle for transmission. A better understanding of the development and life cycle of Cryptosporidium, and new insights into its phylogenetic relationships, have illustrated the need to re-evaluate many aspects of the biology of Cryptosporidium. This has been reinforced by information obtained from the recent successful Cryptosporidium genome sequencing project, which has emphasised the uniqueness of this organism in terms of its parasite life style and evolutionary biology. This chapter provides an up to date review of the biology, biochemistry and host parasite relationships of Cryptosporidium.
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Affiliation(s)
- R C A Thompson
- Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA 6150, Australia.
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Zoonotic parasites in fecal samples and fur from dogs and cats in The Netherlands. Vet Parasitol 2009; 163:115-22. [DOI: 10.1016/j.vetpar.2009.03.044] [Citation(s) in RCA: 174] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Revised: 03/22/2009] [Accepted: 03/26/2009] [Indexed: 11/22/2022]
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Jagai JS, Castronovo DA, Monchak J, Naumova EN. Seasonality of cryptosporidiosis: A meta-analysis approach. ENVIRONMENTAL RESEARCH 2009; 109:465-78. [PMID: 19328462 PMCID: PMC2732192 DOI: 10.1016/j.envres.2009.02.008] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 12/23/2008] [Accepted: 02/11/2009] [Indexed: 05/20/2023]
Abstract
OBJECTIVES We developed methodology for and conducted a meta-analysis to examine how seasonal patterns of cryptosporidiosis, a primarily waterborne diarrheal illness, relate to precipitation and temperature fluctuations worldwide. METHODS Monthly cryptosporidiosis data were abstracted from 61 published epidemiological studies that cover various climate regions based on the Köppen Climate Classification. Outcome data were supplemented with monthly aggregated ambient temperature and precipitation for each study location. We applied a linear mixed-effect model to relate the monthly normalized cryptosporidiosis incidence with normalized location-specific temperature and precipitation data. We also conducted a sub-analysis of associations between the Normalized Difference Vegetation Index (NDVI), a remote sensing measure for the combined effect of temperature and precipitation on vegetation, and cryptosporidiosis in Sub-Saharan Africa. RESULTS Overall, and after adjusting for distance from the equator, increases in temperature and precipitation predict an increase in cryptosporidiosis; the strengths of relationship vary by climate subcategory. In moist tropical locations, precipitation is a strong seasonal driver for cryptosporidiosis whereas temperature is in mid-latitude and temperate climates. When assessing lagged relationships, temperature and precipitation remain strong predictors. In Sub-Saharan Africa, after adjusting for distance from the equator, low NDVI values are predictive of an increase in cryptosporidiosis in the following month. DISCUSSION In this study we propose novel methodology to assess relationships between disease outcomes and meteorological data on a global scale. Our findings demonstrate that while climatic conditions typically define a pathogen habitat area, meteorological factors affect timing and intensity of seasonal outbreaks. Therefore, meteorological forecasts can be utilized to develop focused prevention programs for waterborne cryptosporidiosis.
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Affiliation(s)
- Jyotsna S Jagai
- Department of Public Health and Family Medicine, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA.
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Pelayo L, Nuñez FA, Rojas L, Wilke H, Furuseth Hansen E, Mulder B, Gjerde B, Robertson L. Molecular and epidemiological investigations of cryptosporidiosis in Cuban children. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2009; 102:659-69. [PMID: 19000383 DOI: 10.1179/136485908x355265] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Molecular and epidemiological studies of Cryptosporidium infections amongst 28 Cuban children (aged 2-8 years) with diarrhoea are described. As few of the younger infected children but most of the older infected children had been breastfed, short-term protection from maternal antibodies passed to infants during breastfeeding may result in a lack of cryptosporidial infection in infancy. This protection of breastfeeding children may, however, result in such children developing less anti-Cryptosporidium immunity of their own (than their bottle-fed counterparts), so that, by school age, the children who had been breastfed are those most likely to be found infected. In the present study, in contrast with the observations made during a previous study of cryptosporidiosis in Cuban children, vomiting was rare (7%) whereas abdominal pain was common (57%). These differences in expression of symptoms between studies may be age-related. As seen in other studies from similar countries, including those of the Caribbean and Latin America, C. hominis was found to predominate, the results of the successful molecular analyses revealing 10 C. hominis infections but no C. parvum. Subgenotyping (at the gp60 locus) indicated that the C. hominis infections included a wide range of subtypes, with isolates from three subtype families (Ia, Ib and Id) being detected.
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Affiliation(s)
- L Pelayo
- Departamento de Parasitología, Instituto de Medicina Tropical Pedro Kourí, Apartado Postal 601, Marianao 13, Ciudad de La Habana, Cuba
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The veterinary public health significance of Giardia and Cryptosporidium: Getting things in perspective. Vet J 2008; 177:309-10. [DOI: 10.1016/j.tvjl.2008.06.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Using infectious intestinal disease surveillance data to explore illness aetiology; a cryptosporidiosis case study. Health Place 2008; 15:333-9. [PMID: 18706849 PMCID: PMC2588663 DOI: 10.1016/j.healthplace.2008.06.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2007] [Revised: 05/29/2008] [Accepted: 06/27/2008] [Indexed: 11/21/2022]
Abstract
Infectious intestinal disease (IID) surveillance data are an under-utilised information source on illness geography. This paper uses a case study of cryptosporidiosis in England and Wales to demonstrate how these data can be converted into area-based rates and the factors underlying illness geography investigated. Ascertainment bias is common in surveillance datasets, and we develop techniques to investigate and control this. Rural areas, locations with many livestock and localities with poor water treatment had elevated levels of cryptosporidiosis. These findings accord with previous research validating the techniques developed. Their use in future studies investigating IID geography is therefore recommended.
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Pollock KGJ, Young D, Smith HV, Ramsay CN. Cryptosporidiosis and filtration of water from Loch Lomond, Scotland. Emerg Infect Dis 2008; 14:115-20. [PMID: 18258090 PMCID: PMC2600157 DOI: 10.3201/eid1401.070562] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Coagulation and rapid gravity filtration coincided with a significant reduction in cryptosporidiosis cases. Previous evidence has suggested an association between consumption of unfiltered water from Loch Lomond, Scotland, and cryptosporidiosis. Before November 1999, this water had been only microstrained and disinfected with chlorine; however, since that time, physical treatment of the water (coagulation, rapid gravity filtration) has been added. To determine risk factors, including drinking water, for cryptosporidiosis, we analyzed data on laboratory-confirmed cases of cryptosporidiosis collected from 1997 through 2003. We identified an association between the incidence of cryptosporidiosis and unfiltered drinking water supplied to the home. The association supports the view that adding a filtration system to minimally treated water can substantially reduce the number of confirmed cryptosporidiosis cases.
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Affiliation(s)
- Kevin G J Pollock
- Gastro-intestinal/Zoonoses Section, Health Protection Scotland, Clifton House, Clifton Place, Glasgow, Scotland, UK.
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Thompson RCA, Palmer CS, O'Handley R. The public health and clinical significance of Giardia and Cryptosporidium in domestic animals. Vet J 2007; 177:18-25. [PMID: 18032076 PMCID: PMC7128580 DOI: 10.1016/j.tvjl.2007.09.022] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Revised: 09/18/2007] [Accepted: 09/21/2007] [Indexed: 11/15/2022]
Abstract
Giardia and Cryptosporidium are common enteric parasites of domestic animals, particularly dogs, cats and livestock. Their occurrence is of potential significance from both clinical and public health perspectives yet, until recently, confusion over the taxonomy of these organisms prevented a clear understanding of the epidemiology of infections with both Giardia and Cryptosporidium. The recent application of molecular epidemiological tools has helped to resolve taxonomic issues, allowing cycles of transmission to be determined. In addition, advances have been made in elucidating mechanisms associated with pathogenesis, whereas only limited progress has been achieved in the areas of chemotherapy and prophylaxis.
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Affiliation(s)
- R C Andrew Thompson
- WHO Collaborating Centre for the Molecular Epidemiology of Parasitic Infections, School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA 6150, Australia.
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Lake IR, Harrison FCD, Chalmers RM, Bentham G, Nichols G, Hunter PR, Kovats RS, Grundy C. Case-control study of environmental and social factors influencing cryptosporidiosis. Eur J Epidemiol 2007; 22:805-11. [PMID: 17891460 PMCID: PMC2071968 DOI: 10.1007/s10654-007-9179-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 08/27/2007] [Indexed: 11/24/2022]
Abstract
We report on the first case-control study to investigate the role of wider environmental and socioeconomic factors upon human cryptosporidiosis. Using GIS the detailed locations of 3368 laboratory-confirmed cases were compared to the locations of an equal number of controls. All cases were genotyped enabling Cryptosporidium hominis and Cryptosporidium parvum to be examined separately. When all cryptosporidiosis cases were analyzed, several location variables were strongly associated with illness: areas with many higher socioeconomic status individuals, many individuals aged less than 4 years, areas with a high estimate of Cryptosporidium applied to land from manure, and areas with poorer water treatment. For C. hominis cases, the strongly significant risk factors were areas with many higher socioeconomic status individuals, areas with many young children and urban areas. Socioeconomic status and areas with many individuals aged less then 4 years had a greater impact for infection with C. hominis than for C. parvum. Policy implications are discussed.
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Affiliation(s)
- Iain R Lake
- School of Environmental Sciences, University of East Anglia, Norwich, UK.
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Angles ML, Chandy JP, Cox PT, Fisher IH, Warnecke MR. Implications of biofilm-associated waterborne Cryptosporidium oocysts for the water industry. Trends Parasitol 2007; 23:352-6. [PMID: 17574922 DOI: 10.1016/j.pt.2007.06.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 05/01/2007] [Accepted: 06/01/2007] [Indexed: 10/23/2022]
Abstract
Waterborne Cryptosporidium has been responsible for drinking water-associated disease outbreaks in a number of developed countries. As a result of the resistance of Cryptosporidium to chlorine, which is typically applied as a final barrier to protect the quality of distributed drinking water, current management practices are focused on source-water management and water treatment as ways of preventing Cryptosporidium from entering drinking-water supplies. In the event that treatment barriers fail, surprisingly little is known of the fate of oocysts once they enter a distribution system. To assess properly the risks of waterborne Cryptosporidium, a more thorough understanding of the fate of oocysts in water distribution systems, with emphasis on Cryptosporidium-biofilm interactions, is required.
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Affiliation(s)
- Mark L Angles
- Sydney Water, 115-123 Bathurst Street, Sydney, New South Wales, 2000, Australia.
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Xiao L, Cama VA, Cabrera L, Ortega Y, Pearson J, Gilman RH. Possible transmission of Cryptosporidium canis among children and a dog in a household. J Clin Microbiol 2007; 45:2014-6. [PMID: 17442794 PMCID: PMC1933110 DOI: 10.1128/jcm.00503-07] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In a longitudinal cohort diarrhea study, a girl living in Lima, Peru, and her brother and dog were diagnosed with Cryptosporidium canis infections during the same period. Both children had transient diarrhea, but the dog was asymptomatic. This is the first report of possible transmission of cryptosporidiosis between humans and dogs.
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Affiliation(s)
- Lihua Xiao
- Division of Parasitic Disease, National Center for Infectious Disease, Center for Disease Control and Prevention, Atlanta, GA 30341-3717, USA.
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Doria MF, Abubakar I, Syed Q, Hughes S, Hunter PR. Perceived causes of sporadic cryptosporidiosis and their relation to sources of information. J Epidemiol Community Health 2007; 60:745-50. [PMID: 16905716 PMCID: PMC2566020 DOI: 10.1136/jech.2005.041731] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND The importance of a person's perceptions about the causes of their disease has been emphasised by research on various diseases. Several studies have found perception may be linked to protective behaviours. OBJECTIVE This study intends to identify the main perceived causes of sporadic cryptosporidiosis, and to analyse some of the factors that may influence respondent's perception. The role of respondents' attributions, the scientific plausibility of perceptions, and the importance of specific information sources are also explored. DESIGN Quantitative and qualitative analyses of data from a case-control study. SETTING General population in Wales and north west England. PARTICIPANTS The study is based on a sample of 411 respondents from Wales and north west of England, whose cryptosporidiosis diagnosis was confirmed by a laboratory. RESULTS The results show that the most frequent perceived causes are water (by drinking it or swimming), contagion (mostly from children), and contaminated food. Perceived causes are qualitatively similar to the ones described in scientific literature, but some quantitative differences are evident. Respondents' certainty in relation to the cause of illness is directly related with plausibility. The most frequent information sources used by respondents were test stool results, environmental health officers, and doctors or nurses. Results suggest that information sources may influence the perception of the causes of cryptosporidiosis. Qualitative data provided a few clues about situations where sporadic and outbreak cases may be confused. CONCLUSION In contrast with outbreaks, various information sources in addition to the media are used by people with sporadic cryptosporidiosis that in turn affects the perception of aetiology. This has implications for the dissemination of information about control measures for cryptosporidiosis and surveillance activities.
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Affiliation(s)
- Miguel F Doria
- School of Medicine, Health Policy and Practice, University of East Anglia, Norwich NR4 7TJ
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Feltus DC, Giddings CW, Schneck BL, Monson T, Warshauer D, McEvoy JM. Evidence supporting zoonotic transmission of Cryptosporidium spp. in Wisconsin. J Clin Microbiol 2006; 44:4303-8. [PMID: 17005736 PMCID: PMC1698413 DOI: 10.1128/jcm.01067-06] [Citation(s) in RCA: 157] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2006] [Revised: 07/23/2006] [Accepted: 09/17/2006] [Indexed: 11/20/2022] Open
Abstract
Cryptosporidium hominis and Cryptosporidium parvum are the primary species of Cryptosporidium that infect humans. C. hominis has an anthroponotic transmission cycle, while C. parvum is zoonotic, infecting cattle and other ruminants, in addition to humans. Most cryptosporidiosis outbreaks in the United States have been caused by C. hominis, and this species is often reported as the primary cause of cryptosporidiosis in this country. However, outbreaks account for only 10% of the overall cryptosporidiosis cases, and there are few data on the species that cause sporadic cases. The present study identified the species/genotypes and subgenotypes of Cryptosporidium in 49 cases of sporadic cryptosporidiosis in Wisconsin during the period from 2003 to 2005. The species/genotype of isolates was determined by PCR restriction fragment length polymorphism analysis of the 18S rRNA and Cryptosporidium oocyst wall protein genes. The C. parvum and C. hominis isolates were subgenotyped by sequence analysis of the GP60 gene. Forty-four of 49 isolates were identified as C. parvum, and 1 was identified as C. hominis. Of the remaining isolates, one was identified as being of the cervine genotype, one was identified as being a cervine genotype variant, and two were identified as being of a novel human genotype, previously reported as W17. Nine different subgenotypes were identified within the C. parvum species, and two of these were responsible for 60% of the cases. In this study we found that most sporadic cases of cryptosporidiosis in Wisconsin are caused by zoonotic Cryptosporidium species, indicating that zoonotic transmission could be more frequently associated with sporadic cases in the United States.
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Affiliation(s)
- Dawn C Feltus
- Department of Veterinary and Microbiological Sciences, North Dakota State University, 1523 Centennial Boulevard, Fargo, ND 58105, USA
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Feng Y, Ortega Y, He G, Das P, Xu M, Zhang X, Fayer R, Gatei W, Cama V, Xiao L. Wide geographic distribution of Cryptosporidium bovis and the deer-like genotype in bovines. Vet Parasitol 2006; 144:1-9. [PMID: 17097231 DOI: 10.1016/j.vetpar.2006.10.001] [Citation(s) in RCA: 213] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 10/03/2006] [Accepted: 10/03/2006] [Indexed: 11/20/2022]
Abstract
Recent studies in the United States reported that approximately 85% of pre-weaned dairy calves were infected with zoonotic Cryptosporidium parvum, whereas only 1-2% of post-weaned calves and 1-2-year-old heifers were infected with this species. Cryptosporidium bovis and Cryptosporidium deer-like genotype were much more prevalent in the post-weaned animals. It is not clear whether the same infection pattern also occurs in other geographic areas. In this study, to determine whether the same Cryptosporidium infection pattern was present in other geographic areas, we genotyped Cryptosporidium specimens collected from two farms in China and India, using specimens from farms in Georgia, USA for comparison. C. bovis was the most common species found in pre- and post-weaned calves in all three areas. In Georgia, the deer-like genotype was found frequently in pre- and post-weaned calves and Cryptosporidium andersoni was found in one post-weaned calf. Both C. bovis and the deer-like genotype were found in the few milking cows examined in Georgia. There were no differences in the small subunit rRNA gene sequences obtained from C. bovis or deer-like genotype among the three areas. One adult yak in China, however, was infected with a species similar to C. bovis, with only three nucleotide mutations in the target gene. All four common bovine Cryptosporidium spp. were differentiated from each other by restriction fragment length polymorphism analysis of PCR products with enzymes SspI and MboII. Thus, both C. bovis and the deer-like genotype are found in all age groups of cattle in diverse geographic areas and host adaptation of C. bovis might have occurred in yaks.
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Affiliation(s)
- Yaoyu Feng
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA
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