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Bugeza JK, Roesel K, Mugizi DR, Alinaitwe L, Kivali V, Kankya C, Moriyon I, Cook EAJ. Sero-prevalence and risk factors associated with occurrence of anti-Brucella antibodies among slaughterhouse workers in Uganda. PLoS Negl Trop Dis 2024; 18:e0012046. [PMID: 38498555 PMCID: PMC10977895 DOI: 10.1371/journal.pntd.0012046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 03/28/2024] [Accepted: 03/03/2024] [Indexed: 03/20/2024] Open
Abstract
INTRODUCTION Brucellosis is a febrile zoonosis occurring among high-risk groups such as livestock keepers and abattoir workers and is a public health priority in Uganda. The technical complexities of bacteriological and molecular methods make serological approaches the cornerstone of diagnosis of human brucellosis in resource limited settings. Therefore, proper application and interpretation of serological tests is central to achieve a correct diagnosis. MATERIALS AND METHODS We conducted a cross-sectional study to estimate the seroprevalence and factors associated with anti-Brucella antibodies among slaughterhouse workers processing ruminants and pigs in three regions of the country with serial testing using a combination of the Rose Bengal Test (RBT) and the BrucellaCapt test. An authorized clinician collected 543 blood samples from consenting abattoir workers as well as attribute medical and social demographic data. Univariable and multivariable logistic regression were used to determine factors associated with anti-Brucella sero-positivity. RESULTS AND DISCUSSION The sero-prevalence among ruminant slaughterhouse workers ranged from 7.3% (95% CI: 4.8-10.7) using BrucellaCapt to 9.0% (95% CI: 6.3-12.7) using RBT. Slaughterhouse workers from the Eastern regions (AOR = 9.84, 95%CI 2.27-69.2, p = 0.006) and those who graze animals for alternative income (AOR = 2.36, 95% CI: 1.91-6.63, p = 0.040) were at a higher risk of exposure to Brucella. Similarly, those who wore Personal Protective Equipment (AOR = 4.83, 95%CI:1.63-18.0, p = 0.009) and those who slaughter cattle (AOR = 2.12, 95%CI: 1.25-6.0, p = 0.006) were at a higher risk of exposure to Brucella. Those who slaughter small ruminants (AOR = 1.54, 95%CI: 1.32-4.01, p = 0.048) were also at a higher risk of exposure to Brucella. CONCLUSIONS AND RECOMMENDATIONS Our study demonstrates the combined practical application of the RBT and BrucellaCapt in the diagnosis of human brucellosis in endemic settings. Both pharmaceutical (e.g., routine testing and timely therapeutic intervention), and non-pharmaceutical (e.g., higher index of suspicion of brucellosis when investigating fevers of unknown origin and observation of strict abattoir hygiene) countermeasures should be considered for control of the disease in high-risk groups.
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Affiliation(s)
- James Katamba Bugeza
- International Livestock Research Institute (ILRI), Kampala, Uganda
- National Livestock Resources Research Institute (NaLIRRI), Kampala, Uganda
- College of Veterinary Medicine, Animal Resources and Biosecurity (CoVAB), Makerere University, Kampala, Uganda
| | - Kristina Roesel
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | | | - Lordrick Alinaitwe
- International Livestock Research Institute (ILRI), Kampala, Uganda
- Veterinary Public Health Institute, Vetsuisse faculty, University of Bern, Bern, Switzerland
| | - Velma Kivali
- International Livestock Research Institute (ILRI), Kampala, Uganda
- Institute of Animal Hygiene and Environmental Health, Freie University of Berlin, Berlin, Germany
| | - Clovice Kankya
- College of Veterinary Medicine, Animal Resources and Biosecurity (CoVAB), Makerere University, Kampala, Uganda
| | - Ignacio Moriyon
- Departamento Microbiología y Parasitología, Universidad de Navarra, Edificio de Investigación c/Irunlarrea 1, Pamplona, Spain
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Alinaitwe L, Aturinda CJ, Lubega A, Kivali V, Bugeza J, Wainaina M, Richter MH, Hoona JJ, Roesel K, Mayer-Scholl A, Cook EAJ, Kankya C, Dürr S. Cross-sectional serosurvey of Leptospira species among slaughter pigs, goats, and sheep in Uganda. PLoS Negl Trop Dis 2024; 18:e0012055. [PMID: 38489377 PMCID: PMC10971767 DOI: 10.1371/journal.pntd.0012055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 03/27/2024] [Accepted: 03/07/2024] [Indexed: 03/17/2024] Open
Abstract
INTRODUCTION Leptospira are a group of bacteria, including pathogenic types that cause leptospirosis. In Uganda, Leptospira exposure has been reported in humans, with domesticated animals being speculated as the source. However, comparable evidence of Leptospira prevalence and circulating serovars/serogroups in animals is only documented for cattle, and dogs. Our study determined Leptospira seroprevalence, associated risk factors and serogroups circulating among slaughtered pigs, goats, and sheep in Uganda. METHODS During an 11-month cross-sectional survey in selected slaughter facilities in three regions of Uganda, we collected blood from 926 pigs, 347 goats, and 116 sheep. The age, sex, breed, and origin of each sampled animal were noted. The samples were tested for anti-Leptospira antibodies using the microscopic agglutination test, based on a panel of 12 serovars belonging to 12 serogroups. RESULTS Leptospira seroprevalence was 26.67% (247/926, 95%CI 23.92-29.61) among pigs, and 21.81% (101/463, 95%CI 18.29-25.80) in goats and sheep (small ruminants). L. interrogans Australis and L. kirschneri Grippotyphosa were the commonest serovars among pigs, as was L. borgpetersenii Tarassovi in small ruminants. Pigs sourced from the Eastern (Odds Ratio [OR] = 2.82, 95%CI 1.84-4.30) and Northern (OR = 3.56, 95%CI 2.52-5.02) regions were more likely to be seropositive, compared to those from the Central region. For small ruminants, being female (OR 2.74, 95% CI 1.69-4.57) and adult (OR 4.47, 95% CI 1.57-18.80) was significantly more associated with Leptospira seropositivity. Conclusion/significance: Detection of a moderate seroprevalence, and several Leptospira serogroups among pigs, sheep, and goats from all regions of Uganda, supports existing reports in cattle and dogs, and implies widespread Leptospira exposure in domestic animals in Uganda. These findings may inform future programs for the control of leptospirosis in livestock in Uganda.
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Affiliation(s)
- Lordrick Alinaitwe
- Human and Animal Health Program, International Livestock Research Institute, Nairobi, Kenya
- Veterinary Public Health Institute, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda
| | - Christopher Joshua Aturinda
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda
| | - Ashiraf Lubega
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda
| | - Velma Kivali
- Human and Animal Health Program, International Livestock Research Institute, Nairobi, Kenya
| | - James Bugeza
- Human and Animal Health Program, International Livestock Research Institute, Nairobi, Kenya
- Vaccinology Research Program, National Livestock Resources Research Institute, Kampala, Uganda
| | - Martin Wainaina
- Department of Biological Safety, Federal Institute for Risk Assessment, Berlin, Germany
| | - Martin H. Richter
- Department of Biological Safety, Federal Institute for Risk Assessment, Berlin, Germany
| | - Jolly Justine Hoona
- Department of Animal Production, Ministry of Agriculture, Animal Industry and Fisheries (MAAIF), Entebbe, Uganda
| | - Kristina Roesel
- Human and Animal Health Program, International Livestock Research Institute, Nairobi, Kenya
| | - Anne Mayer-Scholl
- Department of Biological Safety, Federal Institute for Risk Assessment, Berlin, Germany
| | | | - Clovice Kankya
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda
| | - Salome Dürr
- Veterinary Public Health Institute, University of Bern, Bern, Switzerland
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Bugeza J, Roesel K, Moriyon I, Mugizi D, Alinaitwe L, Kivali V, Kankya C, Cook EAJ. Sero-prevalence and factors associated with anti- Brucella antibodies in slaughter livestock in Uganda. Front Epidemiol 2023; 3:1213592. [PMID: 38455915 PMCID: PMC10910896 DOI: 10.3389/fepid.2023.1213592] [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] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 06/13/2023] [Indexed: 03/09/2024]
Abstract
Introduction Brucellosis is endemic in Uganda and is a major cause of production losses in livestock. Early detection and quantification of the disease is vital for its control and eradication. The aim of this study was to assess the sero-prevalence and factors associated with anti-Brucella antibodies in slaughtered livestock. Materials and methods Sera from 886 cattle, 925 small ruminants, and 900 pigs were collected from regional abattoirs in Northern, Eastern and Central Uganda. To estimate sero-prevalence, sera were serially tested using a combination of the Rose Bengal Test (RBT) and Native Hapten (NH) immunoprecipitation test. True sero-prevalence was estimated using the Rogan-Gladden estimator considering the sensitivity and specificity of the NH immunoprecipitation test. Multivariable logistic regression was used to assess factors associated with seropositivity for anti-Brucella antibodies. Results and discussion Small ruminants showed the highest seroprevalence (6.7%, 95% CI = 4.2-7.1) followed by cattle (3.8%, 95% CI = 2.4-4.9) and pigs (2.8%, 95% CI = 1.1-2.9). Seropositivity for anti-Brucella antibodies was associated with region of origin (OR = 4.6,95%CI=1.49-17.75, p = 0.013) for cattle; sex (OR = 2.90, 95% C = 1.5-6.34, p = 0.004), age (OR=4.04, 95% CI = 1.07-8.52, p = 0.006) and species (OR = 2.53, 95% CI = 1.08-6.98, p = 0.048) for small ruminants; and finally sex for pigs (OR = 2.88, 95% CI = 1.07-8.52, p = 0.041). Progressive control interventions must include both cattle and small ruminants since they play a bigger role in the maintenance and dissemination of Brucella. The interventions should adopt a risk-based approach with regions at higher risk being given top priority. Bacteriological and molecular studies should be undertaken to clarify the role of pigs and the goat-cattle cross infections in the epidemiological cycle of brucellosis in Uganda.
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Affiliation(s)
- James Bugeza
- Department of Animal and Human Health, International Livestock Research Institute (ILRI), Kampala, Uganda
- Vaccinology Research Program, National Livestock Resources Research Institute (NaLIRRI), Kampala, Uganda
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Kristina Roesel
- Department of Animal and Human Health, International Livestock Research Institute, Nairobi, Kenya
| | - Ignacio Moriyon
- Department of Microbiology and Parasitology, ISTUN (Instituto de Salud Tropical) y Depto. Microbiología y Parasitología Universidad de Navarra, Edificio de Investigación, Pamplona, España (Spain)
| | - Denis Mugizi
- Department of Animal and Human Health, International Livestock Research Institute (ILRI), Kampala, Uganda
| | - Lordrick Alinaitwe
- Department of Animal and Human Health, International Livestock Research Institute (ILRI), Kampala, Uganda
| | - Velma Kivali
- Department of Animal and Human Health, International Livestock Research Institute (ILRI), Kampala, Uganda
| | - Clovice Kankya
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
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Cornell TR, Thomas LF, Cook EAJ, Pinchbeck G, Bettridge J, Gordon L, Kivali V, Kiyong’a A, Fèvre EM, Scantlebury CE. Evidence of Histoplasma capsulatum seropositivity and exploration of risk factors for exposure in Busia county, western Kenya: Analysis of the PAZ dataset. PLoS Negl Trop Dis 2023; 17:e0011295. [PMID: 37172015 PMCID: PMC10180684 DOI: 10.1371/journal.pntd.0011295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 04/07/2023] [Indexed: 05/14/2023] Open
Abstract
BACKGROUND Despite recognition of histoplasmosis as a disease of national public health concern in Kenya, the burden of Histoplasma capsulatum in the general population remains unknown. This study examined the human seroprevalence of anti-Histoplasma antibody and explored associations between seropositivity and demographic and environmental variables, in Busia county, western Kenya. METHODOLOGY Biobanked serum samples and associated data, from a previous cross-sectional survey, were examined. Latex agglutination tests to detect the presence of anti-Histoplasma antibody were performed on serum samples from 670 survey respondents, representing 178 households within 102 sub-locations. Potential epidemiologic risk factors for H. capsulatum exposure were explored using multi-level multivariable logistic regression analysis with household and sub-location included as random effects. PRINCIPAL FINDINGS The apparent sample seroprevalence of anti-Histoplasma antibody was 15.5% (n = 104/670, 95% Confidence Interval (CI) 12.9-18.5%). A multivariable logistic regression model identified increased odds of H. capsulatum seropositivity in respondents reporting rats within the household within the previous 12 months (OR = 2.99 90% CI 1.04-8.55, p = 0.04). Compared to respondents aged 25-34 years, the odds of seropositivity were higher in respondents aged 15-24 years (OR = 2.70 90% CI 1.04-6.97, p = 0.04). CONCLUSIONS The seroprevalence result provides a baseline for sample size approximations for future epidemiologic studies of the burden of H. capsulatum exposure in Busia county. The final model explored theoretically plausible risk factors for H. capsulatum exposure in the region. A number of factors may contribute to the complex epidemiological picture impacting H. capsulatum exposure status at the human-animal-environment interface in western Kenya. Focussed H. capsulatum research is warranted to determine the contextual significance of identified associations, and in representative sample populations.
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Affiliation(s)
- Tessa Rose Cornell
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
| | - Lian Francesca Thomas
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | | | - Gina Pinchbeck
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
| | - Judy Bettridge
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Lauren Gordon
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
| | - Velma Kivali
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Alice Kiyong’a
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Eric Maurice Fèvre
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
- International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Claire Elizabeth Scantlebury
- Institute of Infection, Veterinary and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
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Motto SK, Hernandez-Castro LE, Shirima GM, Mengele IJ, Bwatota SF, Bronsvoort BMDC, Lyatuu ET, Komwihangilo DM, Cook EAJ. Seroepidemiology of Leptospira serovar Hardjo and associated risk factors in smallholder dairy cattle in Tanzania. PLoS Negl Trop Dis 2023; 17:e0011199. [PMID: 37018175 PMCID: PMC10075398 DOI: 10.1371/journal.pntd.0011199] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 02/24/2023] [Indexed: 04/06/2023] Open
Abstract
BACKGROUND Smallholder dairy farming is crucial for the Tanzanian dairy sector which generates income and employment for thousands of families. This is more evident in the northern and southern highland zones where dairy cattle and milk production are core economic activities. Here we estimated the seroprevalence of Leptospira serovar Hardjo and quantified potential risk factors associated with its exposure in smallholder dairy cattle in Tanzania. METHODS From July 2019 to October 2020, a cross-sectional survey was carried out in a subset of 2071 smallholder dairy cattle. Information about animal husbandry and health management was collected from farmers, and blood was taken from this subset of cattle. Seroprevalence was estimated and mapped to visualize potential spatial hotspots. The association between a set of animal husbandry, health management and climate variables and ELISA binary results was explored using a mixed effects logistic regression model. RESULTS An overall seroprevalence of 13.0% (95% CI 11.6-14.5%) for Leptospira serovar Hardjo was found in the study animals. There was marked regional variations with the highest seroprevalence in Iringa 30.2% (95% CI 25.1-35.7%) and Tanga 18.9% (95% CI 15.7-22.6) with odds ratios of OR = 8.13 (95% CI 4.23-15.63) and OR = 4.39 (95% CI 2.31-8.37), respectively. Multivariate analysis revealed the individual animal factors that were a significant risk for Leptospira seropositivity in smallholder dairy cattle were: animals over 5 years of age (OR = 1.41, 95% CI 1.05-1.9); and indigenous breed (OR = 2.78, 95% CI 1.47-5.26) compared to crossbred animals SHZ-X-Friesian (OR = 1.48, 95% CI 0.99-2.21) and SHZ-X-Jersey (OR = 0.85, 95% CI 0.43-1.63). Farm management factors significantly associated with Leptospira seropositivity included: hiring or keeping a bull for raising purposes (OR = 1.91, 95% CI 1.34-2.71); distance between farms of more than 100 meters (OR = 1.75, 95% CI 1.16-2.64); cattle kept extensively (OR = 2.31, 95% CI 1.36-3.91); farms without cat for rodent control (OR = 1.87, 95% CI 1.16-3.02); farmers with livestock training (OR = 1.62, 95% CI 1.15-2.27). Temperature (OR = 1.63, 95% CI 1.18-2.26), and the interaction of higher temperature and precipitation (OR = 1.5, 95%CI 1.12-2.01) were also significant risk factors. CONCLUSION This study indicated seroprevalence of Leptospira serovar Hardjo, as well as the risk factors driving dairy cattle leptospirosis exposure in Tanzania. The study showed an overall high leptospirosis seroprevalence with regional variations, where Iringa and Tanga represented the highest seroprevalence and risk. The study highlighted the urgent need to understand the human exposures and risks from this important zoonosis to develop control measures and awareness of the problem and quantify the economic and production impacts through abortion and milk loss. In addition, given that the available data was limited to Leptospira serovar Hardjo, the study recommends more studies to identify serologically the most common serovars in cattle for targeted vaccination and risk reduction.
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Affiliation(s)
- Shabani Kiyabo Motto
- Department of Global Health and Bio-Medical Sciences, School of Life Science and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Tanzania Veterinary Laboratory Agency, Central Veterinary Laboratory, Dar es Salaam, Tanzania
| | | | - Gabriel Mkilema Shirima
- Department of Global Health and Bio-Medical Sciences, School of Life Science and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Isaac Joseph Mengele
- Department of Global Health and Bio-Medical Sciences, School of Life Science and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Tanzania Veterinary Laboratory Agency, Dodoma, Tanzania
| | - Shedrack Festo Bwatota
- Department of Global Health and Bio-Medical Sciences, School of Life Science and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Barend Mark de Clare Bronsvoort
- The Roslin Institute, University of Edinburgh, Easter Bush, The United Kingdom
- Centre for Tropical Livestock Genetics and Health, The Roslin Institute, University of Edinburgh, Easter Bush, The United Kingdom
| | - Eliamoni Titus Lyatuu
- International Livestock Research Institute, Mwenge Coca-Cola Road, Mikocheni, Dar es Salaam, Tanzania
| | | | - Elizabeth Anne Jessie Cook
- International Livestock Research Institute, Nairobi, Kenya
- Centre for Tropical Livestock Genetics and Health, International Livestock Research Institute, Nairobi, Kenya
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Motto SK, Shirima GM, de Clare Bronsvoort BM, Cook EAJ. Epidemiology of leptospirosis in Tanzania: A review of the current status, serogroup diversity and reservoirs. PLoS Negl Trop Dis 2021; 15:e0009918. [PMID: 34784354 PMCID: PMC8631673 DOI: 10.1371/journal.pntd.0009918] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 11/30/2021] [Accepted: 10/16/2021] [Indexed: 11/18/2022] Open
Abstract
Background Tanzania is among the tropical countries of Sub-Saharan Africa with the environmental conditions favorable for transmission of Leptospira. Leptospirosis is a neglected zoonotic disease, and although there are several published reports from Tanzania, the epidemiology, genetic diversity of Leptospira and its host range are poorly understood. Methods We conducted a comprehensive review of human and animal leptospirosis within the 26 regions of the Tanzanian mainland. Literature searches for the review were conducted in PubMed and Google Scholar. We further manually identified studies from reference lists among retrieved studies from the preliminary search. Results We identified thirty-four studies describing leptospirosis in humans (n = 16), animals (n = 14) and in both (n = 4). The number of studies varied significantly across regions. Most of the studies were conducted in Morogoro (n = 16) followed by Kilimanjaro (n = 9) and Tanga (n = 5). There were a range of study designs with cross-sectional prevalence studies (n = 18), studies on leptospirosis in febrile patients (n = 13), a case control study in cattle (n = 1) and studies identifying novel serovars (n = 2). The most utilized diagnostic tool was the microscopic agglutination test (MAT) which detected antibodies to 17 Leptospira serogroups in humans and animals. The Leptospira serogroups with the most diverse hosts were Icterohaemorrhagiae (n = 11), Grippotyphosa (n = 10), Sejroe (n = 10), Pomona (n = 9) and Ballum (n = 8). The reported prevalence of Leptospira antibodies in humans ranged from 0.3–29.9% and risk factors were associated with occupational animal contact. Many potential reservoir hosts were identified with the most common being rodents and cattle. Conclusion Leptospirosis is prevalent in humans and animals in Tanzania, although there is regional and host variation in the reports. Many regions do not have information about the disease in either humans or their animal reservoirs. More studies are required to understand human leptospirosis determinants and the role of livestock in leptospirosis transmission to humans for the development of appropriate control strategies. Bacteria from the genus Leptospira is an important agent for causing a disease called leptospirosis in humans and a range of animal species. Leptospirosis is often under-recognized as it presents varied symptoms that mimic malaria, typhoid, brucellosis and other diseases. More than 250 pathogenic Leptospira serovars are known to cause leptospirosis in humans and animals. The diversity of Leptospira serovars and their distribution in humans and animals is little defined in Tanzania. We conducted a systematic review to gather information on the diversity of Leptospira serovars with their reservoir distribution and the most common diagnostics methods used. We included studies (n = 34) in the review and found 17 serogroups described in 28 studies that utilized microscopic agglutination test (MAT). So far human and other animal hosts including cattle, dogs, pigs, bats, buffalo, fish, rodents, goats, lion, zebra, sheep and shrews have been investigated for leptospirosis in Tanzania. Our results show that cattle and rodents are likely to be important reservoirs of pathogenic Leptospira spp. and can be a source of human leptospirosis principally in the farming system. Further studies are needed to explore predominant serovars in livestock for the development of prevention strategies to reduce transmission and risks in humans.
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Affiliation(s)
- Shabani Kiyabo Motto
- Department of Global Health and Bio-Medical Sciences, School of Life Science and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Tanzania Veterinary Laboratory Agency, Central Veterinary Laboratory, Dar es Salaam, Tanzania
- * E-mail: (SKM); (EAJC)
| | - Gabriel Mkilema Shirima
- Department of Global Health and Bio-Medical Sciences, School of Life Science and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
| | - Barend Mark de Clare Bronsvoort
- The Roslin Institute, University of Edinburgh, Easter Bush, United Kingdom
- Centre for Tropical Livestock Genetics and Health, The Roslin Institute, University of Edinburgh, Easter Bush, United Kingdom
| | - Elizabeth Anne Jessie Cook
- International Livestock Research Institute (ILRI), Nairobi, Kenya
- Centre for Tropical Livestock Genetics and Health, ILRI, Nairobi, Kenya
- * E-mail: (SKM); (EAJC)
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Cook EAJ, Gitahi N, de Glanville WA, Thomas LF, Kariuki S, Kang'ethe E, Fèvre EM. Prevalence and risk factors for exposure to Toxoplasma gondii in slaughterhouse workers in western Kenya. BMC Infect Dis 2021; 21:944. [PMID: 34511066 PMCID: PMC8436527 DOI: 10.1186/s12879-021-06658-8] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 09/06/2021] [Indexed: 01/23/2023] Open
Abstract
Background Toxoplasma gondii is a zoonotic protozoan parasite infecting warm-blooded animals. Infection in people can occur through ingestion of oocysts passed in the faeces of the definitive hosts; ingestion of bradyzoites in the tissue of infected intermediate hosts; or exposure to tachyzoites in raw milk and eggs. Slaughterhouse workers are considered a high-risk group for T. gondii exposure because of their contact with raw meat, although a positive relationship between handling raw meat and T. gondii seropositivity has not been demonstrated in all studies. This study aimed to determine the seroprevalence of antibodies to T. gondii in slaughterhouse workers in Kenya and identify risk factors associated with seropositivity. Methods A survey of slaughterhouse workers was conducted in 142 slaughter facilities in the study area. Information regarding demographics, contact with livestock, meat consumption, and practices in the slaughterhouse was collected using structured questionnaires. Commercial ELISAs were used to detect IgM and IgG antibodies against T. gondii and a multi-level logistic regression model was used to identify potential risk factors for seropositivity in slaughterhouse workers. Results The apparent prevalence of antibodies to T. gondii was 84.0% (95% Confidence Interval (CI) 81.2–86.5%) for IgG and 2.2% (95% CI 1.3–3.5%) for IgM antibodies. All IgM positive individuals were IgG positive. Risk factors for exposure to T. gondii were: increasing age (Odds Ratio (OR) 1.03; 95% CI 1.01–1.05); owning poultry (OR 2.00; 95% CI 1.11–3.62); and consuming animal blood (OR 1.92; 95% CI 1.21–3.03). Conclusions The seroprevalence of antibodies to T. gondii was very high in this population and considerably higher than published values in the general population. Risk factors included age, owning poultry and drinking animal blood which were consistent with previous reports but none were specifically associated with working in the slaughterhouse. In this instance slaughterhouse workers may represent a useful sentinel for the general population where the level of exposure is also likely to be high and may signify an unidentified public health risk to vulnerable groups such as pregnant women. A detailed understanding of the epidemiology of infection is required, which should include an assessment of incidence, mortality, and burden since T. gondii infection is likely to have life-long sequelae.
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Affiliation(s)
- Elizabeth Anne Jessie Cook
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, Nairobi, 00100, Kenya. .,Institute of Infection Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK.
| | - Nduhiu Gitahi
- University of Nairobi, P.O. Box 29053, Nairobi, 00625, Kenya
| | - William Anson de Glanville
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, Nairobi, 00100, Kenya.,Center for One Health, University of Global Health Equity, Kigali, Rwanda
| | - Lian F Thomas
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, Nairobi, 00100, Kenya.,Institute of Infection Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK
| | - Samuel Kariuki
- Kenya Medical Research Institute, P.O. Box 19464, Nairobi, 00200, Kenya
| | | | - Eric Maurice Fèvre
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, Nairobi, 00100, Kenya.,Institute of Infection Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK
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8
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Cook EAJ, de Glanville WA, Thomas LF, Kiyong'a A, Kivali V, Kariuki S, Bronsvoort BMDC, Fèvre EM. Evidence of exposure to C. burnetii among slaughterhouse workers in western Kenya. One Health 2021; 13:100305. [PMID: 34430697 PMCID: PMC8367830 DOI: 10.1016/j.onehlt.2021.100305] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 08/06/2021] [Accepted: 08/06/2021] [Indexed: 12/02/2022] Open
Abstract
Q fever, caused by C. burnetii, has been reported in slaughterhouse workers worldwide. The most reported risk factor for seropositivity is the workers' role in the slaughterhouse. This study examined the seroprevalence and risk factors for antibodies to C. burnetii in slaughterhouse workers in western Kenya to fill a data gap relating to this emerging disease in East Africa. Individuals were recruited from all consenting slaughterhouses in the study area between February and November 2012. Information was collected from participating workers regarding demographic data, animals slaughtered and role in the slaughterhouse. Sera samples were screened for antibodies to C. burnetii using a commercial ELISA and risk factors associated with seropositivity were identified using multi-level logistic regression analysis. Slaughterhouse workers (n = 566) were recruited from 84 ruminant slaughterhouses in western Kenya. The seroprevalence of antibodies to C. burnetii was 37.1% (95% Confidence Interval (CI) 33.2–41.2%). The risk factors identified for C. burnetii seropositivity included: male workers compared to female workers, odds ratio (OR) 5.40 (95% CI 1.38–21.22); slaughtering cattle and small ruminants compared to those who only slaughtered cattle, OR 1.52 (95% CI 1.06–2.19). In addition, specific roles in the slaughterhouse were associated with increased odds of being seropositive, including cleaning the slaughterhouse, OR 3.98 (95% CI 1.39–11.43); cleaning the intestines, OR 3.24 (95% CI 1.36–7.73); and flaying the carcass OR 2.63 (95% CI 1.46–4.75) compared to being the slaughterman or foreman. We identified that slaughterhouse workers have a higher seroprevalence of antibodies to C. burnetii compared to published values in the general population from the same area. Slaughterhouse workers therefore represent an occupational risk group in this East African setting. Workers with increased contact with the viscera and fluids are at higher risk for exposure to C. burnetii. Education of workers may reduce transmission, but an alternative approach may be to consider the benefits of vaccination in high-risk groups.
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Affiliation(s)
| | - William Anson de Glanville
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya.,Center for One Health, University of Global Health Equity, Rwanda
| | - Lian Francesca Thomas
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya.,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK
| | - Alice Kiyong'a
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya
| | - Velma Kivali
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya
| | - Samuel Kariuki
- Kenya Medical Research Institute, PO Box 19464-00200, Nairobi, Kenya
| | - Barend Mark de Clare Bronsvoort
- Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK.,Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK
| | - Eric Maurice Fèvre
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya.,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK
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9
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Ngugi JN, Fèvre EM, Mgode GF, Obonyo M, Mhamphi GG, Otieno CA, Cook EAJ. Seroprevalence and associated risk factors of leptospirosis in slaughter pigs; a neglected public health risk, western Kenya. BMC Vet Res 2019; 15:403. [PMID: 31703588 PMCID: PMC6842184 DOI: 10.1186/s12917-019-2159-3] [Citation(s) in RCA: 20] [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] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 10/28/2019] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Leptospirosis is a neglected zoonosis of public health importance transmitted through contact with contaminated soil, water or urine of infected animals. In pigs the disease is characterized by abortion, still births and weak piglets. A cross-sectional study was conducted in May to July 2018 to estimate the sero-prevalence of leptospirosis and factors associated with seropositivity in slaughter pigs. A questionnaire was used to collect information on animal demographics. Serum was tested for anti-leptospiral antibodies using microscopic agglutination test (MAT) with a panel of 8 serovars. Sera were considered positive for sero-reactivity at a MAT titre ≥1:40 against at least one serovar. Chi-square tests were used to measure the strength of association between the MAT test result and exploratory variables. RESULTS A total of 252 pig serum samples from seven slaughterhouses were tested for Leptospira antibodies by MAT. Of the 252 pigs sampled, 88.8% (244/252) were indigenous breeds; 55.6% (140/252) were female and 88.7% (220/252) were reared in extensive production systems. Eighty-three (32.9%; 83/252) sera samples tested positive on MAT against at least one serovar. Of the 8 serovars, the highest prevalence was recorded for serovar Lora 21.4% followed by Kenya 5.2%, Sokoine 3.6% and Grippotyphosa at 3.2%. Risk factors for leptospirosis seropositivity in pigs were: originating from farms with other types of livestock (OR 2.3; 95% CI 1.0-4.5) and mature pigs (OR 1.9; 95% CI 1.1-3.3). CONCLUSION This study demonstrates that there is a high prevalence of leptospirosis positive pigs at slaughter in a small-holder livestock keeping region of the Lake Victoria basin. The potential for cross species transmission of pathogenic serovars is highlighted as well as the potential for occupational exposure to slaughterhouse personnel. Improvements in husbandry practices (confinement and rodent control) and public health education among slaughterhouse workers and other high-risk groups is recommended.
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Affiliation(s)
- Jeremiah N Ngugi
- Field Epidemiology and Laboratory Training Program, Kenyatta National Hospital, P.O. Box 22313, Nairobi, 00100, Kenya. .,County Government of Taita Taveta, P.O. Box 1066-80304, Wundanyi, Kenya.
| | - Eric M Fèvre
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, Nairobi, 00100, Kenya.,Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK
| | - Georgies F Mgode
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Mark Obonyo
- Field Epidemiology and Laboratory Training Program, Kenyatta National Hospital, P.O. Box 22313, Nairobi, 00100, Kenya.,Ministry of Agriculture, Livestock and Fisheries, Directorate of Veterinary Services, Nairobi, Kenya
| | - Ginethon G Mhamphi
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | | | - Elizabeth Anne Jessie Cook
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, Nairobi, 00100, Kenya. .,Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK.
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10
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Orono SA, Gitao GC, Mpatswenumugabo JP, Chepkwony M, Mutisya C, Okoth E, Bronsvoort BMDC, Russell GC, Nene V, Cook EAJ. Field validation of clinical and laboratory diagnosis of wildebeest associated malignant catarrhal fever in cattle. BMC Vet Res 2019; 15:69. [PMID: 30819152 PMCID: PMC6396541 DOI: 10.1186/s12917-019-1818-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [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: 08/10/2018] [Accepted: 02/22/2019] [Indexed: 11/16/2022] Open
Abstract
Background Wildebeest associated malignant catarrhal fever (WA-MCF) is a fatal disease of cattle. Outbreaks are seasonal and associated with close interaction between cattle and calving wildebeest. In Kenya, WA-MCF has a dramatic effect on cattle-keepers who lose up to 10% of their cattle herds per year. The objective of this study was to report the impact of WA-MCF on a commercial ranch and assess the performance of clinical diagnosis compared to laboratory diagnosis as a disease management tool. A retrospective study of WA-MCF in cattle was conducted from 2014 to 2016 at Kapiti Plains Ranch Ltd., Kenya. During this period, 325 animals showed clinical signs of WA-MCF and of these, 123 were opportunistically sampled. In addition, 51 clinically healthy animals were sampled. Nested polymerase chain reaction (PCR) and indirect enzyme linked immunosorbent assay (ELISA) were used to confirm clinically diagnosed cases of WA-MCF. A latent class model (LCM) was used to evaluate the diagnostic parameters of clinical diagnosis and the tests in the absence of a gold standard. Results By PCR, 94% (95% C.I. 89–97%) of clinically affected animals were positive to WA-MCF while 63% (95% C.I. 54–71%) were positive by indirect ELISA. The LCM demonstrated the indirect ELISA had poor sensitivity 63.3% (95% PCI 54.4–71.7%) and specificity 62.6% (95% PCI 39.2–84.9%) while the nested PCR performed better with sensitivity 96.1% (95% PCI 90.7–99.7%) and specificity 92.9% (95% PCI 76.1–99.8%). The sensitivity and specificity of clinical diagnosis were 99.1% (95% PCI 96.8–100.0%) and 71.5% (95% PCI 48.0–97.2%) respectively. Conclusions Clinical diagnosis was demonstrated to be an effective method to identify affected animals although animals may be incorrectly classified resulting in financial loss. The study revealed indirect ELISA as a poor test and nested PCR to be a more appropriate confirmatory test for diagnosing acute WA-MCF. However, the logistics of PCR make it unsuitable for field diagnosis of WA-MCF. The future of WA-MCF diagnosis should be aimed at development of penside techniques, which will allow for fast detection in the field. Electronic supplementary material The online version of this article (10.1186/s12917-019-1818-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sheillah Ayiela Orono
- Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi, P. O. Box, 29053, Kangemi, Kenya.,International Livestock Research Institute, Old Naivasha Road, P. O. Box 30709, Nairobi, Kenya
| | - George Chege Gitao
- Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi, P. O. Box, 29053, Kangemi, Kenya
| | - Jean Pierre Mpatswenumugabo
- Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi, P. O. Box, 29053, Kangemi, Kenya.,Department of Veterinary Medicine, University of Rwanda, P.O. Box: 210, Musanze, Rwanda
| | - Maurine Chepkwony
- International Livestock Research Institute, Old Naivasha Road, P. O. Box 30709, Nairobi, Kenya
| | - Christine Mutisya
- International Livestock Research Institute, Old Naivasha Road, P. O. Box 30709, Nairobi, Kenya
| | - Edward Okoth
- International Livestock Research Institute, Old Naivasha Road, P. O. Box 30709, Nairobi, Kenya
| | | | | | - Vishvanath Nene
- International Livestock Research Institute, Old Naivasha Road, P. O. Box 30709, Nairobi, Kenya
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11
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de Glanville WA, Thomas LF, Cook EAJ, Bronsvoort BMDC, Wamae NC, Kariuki S, Fèvre EM. Household socio-economic position and individual infectious disease risk in rural Kenya. Sci Rep 2019; 9:2972. [PMID: 30814567 PMCID: PMC6393457 DOI: 10.1038/s41598-019-39375-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 01/22/2019] [Indexed: 11/21/2022] Open
Abstract
The importance of household socio-economic position (SEP) in shaping individual infectious disease risk is increasingly recognised, particularly in low income settings. However, few studies have measured the extent to which this association is consistent for the range of pathogens that are typically endemic among the rural poor in the tropics. This cross-sectional study assessed the relationship between SEP and human infection within a single community in western Kenya using a set of pathogens with diverse transmission routes. The relationships between household SEP and individual infection with Plasmodium falciparum, hookworm (Ancylostoma duodenale and/or Necator americanus), Entamoeba histolytica/dispar, Mycobacterium tuberculosis, and HIV, and co-infections between hookworm, P. falciparum and E. histolytica/dispar, were assessed using multivariable logistic and multinomial regression. Individuals in households with the lowest SEP were at greatest risk of infection with P. falciparum, hookworm and E. histolytica/dispar, as well as co-infection with each pathogen. Infection with M. tuberculosis, by contrast, was most likely in individuals living in households with the highest SEP. There was no evidence of a relationship between individual HIV infection and household SEP. We demonstrate the existence of a household socio-economic gradient within a rural farming community in Kenya which impacts upon individual infectious disease risk. Structural adjustments that seek to reduce poverty, and therefore the socio-economic inequalities that exist in this community, would be expected to substantially reduce overall infectious disease burden. However, policy makers and researchers should be aware that heterogeneous relationships can exist between household SEP and infection risk for different pathogens in low income settings.
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Affiliation(s)
- W A de Glanville
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT, UK.
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya.
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
| | - L F Thomas
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT, UK
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya
| | - E A J Cook
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT, UK
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya
| | - B M de C Bronsvoort
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, UK
- Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, UK
| | - N C Wamae
- School of Pharmacy and Health Sciences, United States International University-Africa, PO Box 14634-01000, Nairobi, Kenya
| | - S Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, PO Box 19464-00200, Nairobi, Kenya
| | - E M Fèvre
- International Livestock Research Institute, Old Naivasha Road, PO BOX 30709, 00100, Nairobi, Kenya.
- Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK.
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12
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Cook EAJ, Grossi-Soyster EN, de Glanville WA, Thomas LF, Kariuki S, Bronsvoort BMDC, Wamae CN, LaBeaud AD, Fèvre EM. The sero-epidemiology of Rift Valley fever in people in the Lake Victoria Basin of western Kenya. PLoS Negl Trop Dis 2017; 11:e0005731. [PMID: 28686589 PMCID: PMC5517073 DOI: 10.1371/journal.pntd.0005731] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 07/19/2017] [Accepted: 06/20/2017] [Indexed: 12/25/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a zoonotic arbovirus affecting livestock and people. This study was conducted in western Kenya where RVFV outbreaks have not previously been reported. The aims were to document the seroprevalence and risk factors for RVFV antibodies in a community-based sample from western Kenya and compare this with slaughterhouse workers in the same region who are considered a high-risk group for RVFV exposure. The study was conducted in western Kenya between July 2010 and November 2012. Individuals were recruited from randomly selected homesteads and a census of slaughterhouses. Structured questionnaire tools were used to collect information on demographic data, health, and risk factors for zoonotic disease exposure. Indirect ELISA on serum samples determined seropositivity to RVFV. Risk factor analysis for RVFV seropositivity was conducted using multi-level logistic regression. A total of 1861 individuals were sampled in 384 homesteads. The seroprevalence of RVFV in the community was 0.8% (95% CI 0.5–1.3). The variables significantly associated with RVFV seropositivity in the community were increasing age (OR 1.2; 95% CI 1.1–1.4, p<0.001), and slaughtering cattle at the homestead (OR 3.3; 95% CI 1.0–10.5, p = 0.047). A total of 553 slaughterhouse workers were sampled in 84 ruminant slaughterhouses. The seroprevalence of RVFV in slaughterhouse workers was 2.5% (95% CI 1.5–4.2). Being the slaughterman, the person who cuts the animal’s throat (OR 3.5; 95% CI 1.0–12.1, p = 0.047), was significantly associated with RVFV seropositivity. This study investigated and compared the epidemiology of RVFV between community members and slaughterhouse workers in western Kenya. The data demonstrate that slaughtering animals is a risk factor for RVFV seropositivity and that slaughterhouse workers are a high-risk group for RVFV seropositivity in this environment. These risk factors have been previously reported in other studies providing further evidence for RVFV circulation in western Kenya. Rift Valley fever virus (RVFV) is a zoonotic virus affecting livestock and people. Periodic outbreaks in Kenya are associated with greater than average rainfall, although outbreaks have not previously been reported in western Kenya. The virus is spread between animals and to people by mosquitos. Contact with infected animal tissues and products are also risk factors for transmission of RVFV to people. This study investigated the seroprevalence of RVFV in 1861 residents of western Kenya and compared this to the seroprevalence in 553 ruminant slaughterhouse workers. The seroprevalence of RVFV in people in western Kenya was less than 1%, which is consistent with previous reports from the region. Slaughterhouse workers were shown to be a higher risk group for RVFV seropositivity, with seroprevalence of 2.5%. The identification of plausible risk factors including slaughtering is consistent with reports from other regions. The results suggest that it is plausible that RVFV virus is circulating in western Kenya. Improved surveillance in low risk areas is recommended particularly during countrywide outbreaks.
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Affiliation(s)
- Elizabeth Anne Jessie Cook
- Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
- International Livestock Research Institute, Nairobi, Kenya
- * E-mail: (EAJC); (EF)
| | | | - William Anson de Glanville
- Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
- International Livestock Research Institute, Nairobi, Kenya
| | - Lian Francesca Thomas
- Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
- International Livestock Research Institute, Nairobi, Kenya
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Barend Mark de Clare Bronsvoort
- The Roslin Institute, University of Edinburgh, Roslin, United Kingdom
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, United Kingdom
| | | | - Angelle Desiree LaBeaud
- Department of Pediatrics, Stanford University School of Medicine, Stanford, United States of America
| | - Eric Maurice Fèvre
- International Livestock Research Institute, Nairobi, Kenya
- Institute of Infection and Global Health, University of Liverpool, Neston, United Kingdom
- * E-mail: (EAJC); (EF)
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13
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Makau DN, Gitau GK, Muchemi GK, Thomas LF, Cook EAJ, Wardrop NA, Fèvre EM, de Glanville WA. Environmental predictors of bovine Eimeria infection in western Kenya. Trop Anim Health Prod 2017; 49:409-416. [PMID: 28054227 PMCID: PMC5253148 DOI: 10.1007/s11250-016-1209-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 12/05/2016] [Indexed: 11/24/2022]
Abstract
Eimeriosis is caused by a protozoan infection affecting most domestic animal species. Outbreaks in cattle are associated with various environmental factors in temperate climates but limited work has been done in tropical settings. The objective of this work was to determine the prevalence and environmental factors associated with bovine Eimeria spp. infection in a mixed farming area of western Kenya. A total of 983 cattle were sampled from 226 cattle-keeping households. Faecal samples were collected directly from the rectum via digital extraction and analysed for the presence of Eimeria spp. infection using the MacMaster technique. Individual and household level predictors of infection were explored using mixed effects logistic regression. The prevalence of individual animal Eimeria infection was 32.8% (95% CI 29.9-35.9). A positive linear relationship was found between risk of Eimeria infection and increasing temperature (OR = 1.4, 95% CI 1.06-1.86) and distance to areas at risk of flooding (OR = 1.49, 95% CI 1.17-1.91). There was weak evidence of non-linear relationship between Eimeria infection and the proportion of the area around a household that was classified as swamp (OR = 1.12, 95% CI 0.87-1.44; OR (quadratic term) = 0.85, 95% CI 0.73-1.00), and the sand content of the soil (OR = 1.18, 95% CI 0.91-1.53; OR (quadratic term) = 1.1, 95% CI 0.99-1.23). The risk of animal Eimeria spp. infection is influenced by a number of climatic and soil-associated conditions.
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Affiliation(s)
- D N Makau
- Department of Public Health Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Nairobi, Nairobi, PO BOX 29053-00625, Kenya.
| | - G K Gitau
- Department of Clinical Studies, Faculty of Veterinary Medicine, University of Nairobi, Nairobi, PO BOX 29053-00625, Kenya
| | - G K Muchemi
- Department of Public Health Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Nairobi, Nairobi, PO BOX 29053-00625, Kenya
| | - L F Thomas
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709-00100, Nairobi, Kenya
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, Kings Buildings, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK
| | - E A J Cook
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709-00100, Nairobi, Kenya
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, Kings Buildings, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK
| | - N A Wardrop
- Geography and Environment, University of Southampton, Highfield Campus, University Road, Southampton, SO17 1BJ, UK
| | - E M Fèvre
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709-00100, Nairobi, Kenya
- Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK
| | - W A de Glanville
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709-00100, Nairobi, Kenya.
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, Kings Buildings, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JT, UK.
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14
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Cook EAJ, de Glanville WA, Thomas LF, Kariuki S, Bronsvoort BMDC, Fèvre EM. Working conditions and public health risks in slaughterhouses in western Kenya. BMC Public Health 2017; 17:14. [PMID: 28056885 PMCID: PMC5217581 DOI: 10.1186/s12889-016-3923-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 12/09/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Inadequate facilities and hygiene at slaughterhouses can result in contamination of meat and occupational hazards to workers. The objectives of this study were to assess current conditions in slaughterhouses in western Kenya and the knowledge, and practices of the slaughterhouse workers toward hygiene and sanitation. METHODS Between February and October 2012 all consenting slaughterhouses in the study area were recruited. A standardised questionnaire relating to facilities and practices in the slaughterhouse was administered to the foreperson at each site. A second questionnaire was used to capture individual slaughterhouse workers' knowledge, practices and recent health events. RESULTS A total of 738 slaughterhouse workers from 142 slaughterhouses completed questionnaires. Many slaughterhouses had poor infrastructure, 65% (95% CI 63-67%) had a roof, cement floor and walls, 60% (95% CI 57-62%) had a toilet and 20% (95% CI 18-22%) had hand-washing facilities. The meat inspector visited 90% (95% CI 92-95%) of slaughterhouses but antemortem inspection was practiced at only 7% (95% CI 6-8%). Nine percent (95% CI 7-10%) of slaughterhouses slaughtered sick animals. Only half of workers wore personal protective clothing - 53% (95% CI 51-55%) wore protective coats and 49% (95% CI 46-51%) wore rubber boots. Knowledge of zoonotic disease was low with only 31% (95% CI 29-33%) of workers aware that disease could be transmitted from animals. CONCLUSIONS The current working conditions in slaughterhouses in western Kenya are not in line with the recommendations of the Meat Control Act of Kenya. Current facilities and practices may increase occupational exposure to disease or injury and contaminated meat may enter the consumer market. The findings of this study could enable the development of appropriate interventions to minimise public health risks. Initially, improvements need to be made to facilities and practices to improve worker safety and reduce the risk of food contamination. Simultaneously, training programmes should target workers and inspectors to improve awareness of the risks. In addition, education of health care workers should highlight the increased risks of injury and disease in slaughterhouse workers. Finally, enhanced surveillance, targeting slaughterhouse workers could be used to detect disease outbreaks. This "One Health" approach to disease surveillance is likely to benefit workers, producers and consumers.
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Affiliation(s)
- Elizabeth Anne Jessie Cook
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT UK
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya
| | - William Anson de Glanville
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT UK
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya
| | - Lian Francesca Thomas
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, West Mains Road, Edinburgh, EH9 3JT UK
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, PO Box 19464–00200, Nairobi, Kenya
| | - Barend Mark de Clare Bronsvoort
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG UK
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG UK
| | - Eric Maurice Fèvre
- International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya
- Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE UK
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Cook EAJ, de Glanville WA, Thomas LF, Kariuki S, Bronsvoort BMDC, Fèvre EM. Risk factors for leptospirosis seropositivity in slaughterhouse workers in western Kenya. Occup Environ Med 2016; 74:357-365. [PMID: 27913579 PMCID: PMC5520261 DOI: 10.1136/oemed-2016-103895] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [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: 06/08/2016] [Revised: 10/31/2016] [Accepted: 11/12/2016] [Indexed: 01/15/2023]
Abstract
OBJECTIVES Leptospirosis has been documented in slaughterhouse workers around the world. Risk factors include smoking and drinking at work, and performing tasks such as cleaning offal. This paper examined risk factors for leptospirosis seropositivity in slaughterhouse workers in western Kenya. METHODS The study was conducted between May 2011 and October 2012. Questionnaires were used to collect information from workers on demographic data, health and hygiene practices in the slaughterhouse. A commercial ELISA detected antibodies to Leptospira spp. in serum samples and multilevel logistic regression analysis identified factors associated with leptospirosis seropositivity. RESULTS A total of 737 workers from 142 slaughterhouses were recruited. The seroprevalence of antibodies to Leptospira spp. was 13.4% (95% CI 11.1% to 16.1%). Risk factors included: having wounds (OR 3.1; 95% CI 1.5 to 6.1); smoking (OR 1.8; 95% CI 1.1 to 2.9); eating at work (OR 2.1; 95% CI 1.2 to 3.6); cleaning the offal (OR 5.1; 95% CI 1.8 to 15.0); and having a borehole for personal water use (OR 2.3; 95% CI 1.1 to 4.7). At the slaughterhouse level, risk factors included having a roof (OR 2.6; 95% CI 1.2 to 5.6) and drawing water from a well (OR 2.2; 95% CI 1.2 to 4.0). Protective factors included working in slaughterhouses where antemortem inspection was conducted (OR 0.6; 95% CI 0.4 to 1.0) and where workers wore protective aprons (OR 0.4; 95% CI 0.2 to 0.7). CONCLUSIONS This is the first report of leptospirosis seropositivity in slaughterhouse workers in Kenya. Potential risk factors were identified and this information can be used to educate workers regarding their disease risks and ways to prevent or reduce transmission.
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Affiliation(s)
- Elizabeth Anne Jessie Cook
- Ashworth Laboratories, Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.,International Livestock Research Institute, Nairobi, Kenya
| | - William Anson de Glanville
- Ashworth Laboratories, Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.,International Livestock Research Institute, Nairobi, Kenya
| | - Lian Francesca Thomas
- Ashworth Laboratories, Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.,International Livestock Research Institute, Nairobi, Kenya
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Barend Mark de Clare Bronsvoort
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.,Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK
| | - Eric Maurice Fèvre
- International Livestock Research Institute, Nairobi, Kenya.,Institute of Infection and Global Health, University of Liverpool, Neston, UK
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