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Ngobeni R, Gilchrist C, Samie A. Prevalence and Distribution of Cryptosporidium spp. and Giardia lamblia in Rural and Urban Communities of South Africa. TURKIYE PARAZITOLOJII DERGISI 2022; 46:14-19. [PMID: 35232700 DOI: 10.4274/tpd.galenos.2021.37039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
OBJECTIVE Enteric diseases remain a serious health problem globally. High prevalence is evident in regions with poor socioeconomic conditions, poor sanitation, and inadequate clean water supply, such as South Africa. Designing an effective strategy, however, requires local knowledge, which can be particularly challenging to acquire in low-and middle-income countries. As the first step in this process, we investigated the prevalence and distribution of protozoan parasites Cryptosporidium and Giardia in the rural and urban gastrointestinal clinics of South Africa. METHODS A cross-sectional study was conducted to assess the prevalence of enteric parasites Cryptosporidium and G. lamblia in rural and urban communities of South Africa. Stool samples were collected from November 2013 to June 2015 from patients with diarrhea (n=227) and without diarrhea (n=257). DNA was extracted and a diagnostic Taqman qPCR assay was performed to detect these protozoan parasites, which was further confirmed by the Sanger sequencing of a few samples. RESULTS Of the 484 stool specimens collected, 34% (166/484) were positive for either Cryptosporidium spp. or Giardia lamblia parasites, with only 5% containing both parasites (22/484). In both study populations, Cryptosporidium was the most prevalent parasite (overall 25%) followed by Giardia (19%). CONCLUSION This study discovered that both Giardia and Cryptosporidium parasites might contribute to diarrheal disease in South Africa and are more prevalent in rural communities. Future studies are needed to identify the source of the infection and design appropriate interventions to reduce the burden of the disease. AMAÇ Enterik hastalıklar küresel olarak ciddi bir sağlık sorunu olmaya devam etmektedir. Güney Afrika gibi düşük sosyo-ekonomik koşulların, kötü sanitasyonun ve yetersiz temiz su kaynaklarının olduğu bölgelerde yüksek prevalans görülmektedir. Ancak etkili bir strateji tasarlamak için, düşük ve orta gelirli ülkelerde edinilmesi özellikle zor olabilecek yerel bir bilgi gerektirmektedir. Bu süreçte biz ilk adım olarak, Güney Afrika’nın kırsal ve kentsel gastrointestinal kliniklerinde protozoan parazitler Cryptosporidium ve Giardia’nın prevalansını ve dağılımını araştırdık. YÖNTEMLER Güney Afrika’nın kırsal ve kentsel topluluklarında Cryptosporidium ve G. lamblia enterik parazitlerinin sıklığını araştırmak için kesitsel bir çalışma yapıldı. İshali olan (n=227) ve olmayan (n=257) hastaların Kasım 2013-Haziran 2015 tarihleri arasında dışkı örnekleri toplandı. DNA ekstrakte edildi ve bu protozoan parazitleri saptamak için tanısal bir Taqman qPCR tahlili kullanılarak, birkaç örnek Sanger dizilimi ile daha da doğrulandı. BULGULAR Toplanan 484 dışkı örneğinin %34’ü (166/484) Cryptosporidium spp. veya Giardia lamblia parazitleri için pozitifti ve örneklerin sadece %5’i her iki paraziti de içeriyordu (22/484). Her iki çalışma popülasyonunda da Cryptosporidium en yaygın parazitti (toplam %25) ve bunu Giardia (%19) izledi. SONUÇ Bu çalışma, hem Giardia hem de Cryptosporidium parazitlerinin Güney Afrika’daki ishal hastalığına katkıda bulunabileceğini ve kırsal topluluklarda daha yaygın olduğunu göstermiştir. Hem enfeksiyonun kaynağını belirlemek hem de hastalığın yükünü azaltmak için uygun müdahaleleri tasarlamak için gelecekteki çalışmalara ihtiyaç vardır.
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Affiliation(s)
- Renay Ngobeni
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Bellville, South Africa
| | | | - Amidou Samie
- Department of Microbiology, University of Venda, Private Bag, Limpopo, South Africa
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Messa A, Köster PC, Garrine M, Nhampossa T, Massora S, Cossa A, Bassat Q, Kotloff K, Levine MM, Alonso PL, Carmena D, Mandomando I. Molecular Characterisation of Cryptosporidium spp. in Mozambican Children Younger than 5 Years Enrolled in a Matched Case-Control Study on the Aetiology of Diarrhoeal Disease. Pathogens 2021; 10:452. [PMID: 33918893 PMCID: PMC8070020 DOI: 10.3390/pathogens10040452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 11/16/2022] Open
Abstract
Cryptosporidium is a leading cause of childhood diarrhoea and associated physical and cognitive impairment in low-resource settings. Cryptosporidium-positive faecal samples (n = 190) from children aged ≤ 5 years enrolled in the Global Enteric Multicenter Study (GEMS) in Mozambique detected by ELISA (11.5%, 430/3754) were successfully PCR-amplified and sequenced at the gp60 or ssu rRNA loci for species determination and genotyping. Three Cryptosporidium species including C. hominis (72.6%, 138/190), C. parvum (22.6%, 43/190), and C. meleagridis (4.2%, 8/190) were detected. Children ≤ 23 months were more exposed to Cryptosporidium spp. infections than older children. Both C. hominis and C. parvum were more prevalent among children with diarrhoeal disease compared to those children without it (47.6% vs. 33.3%, p = 0.007 and 23.7% vs. 11.8%, p = 0.014, respectively). A high intra-species genetic variability was observed within C. hominis (subtype families Ia, Ib, Id, Ie, and If) and C. parvum (subtype families IIb, IIc, IIe, and IIi) but not within C. meleagridis (subtype family IIIb). No association between Cryptosporidium species/genotypes and child's age was demonstrated. The predominance of C. hominis and C. parvum IIc suggests that most of the Cryptosporidium infections were anthroponotically transmitted, although zoonotic transmission events also occurred at an unknown rate. The role of livestock, poultry, and other domestic animal species as sources of environmental contamination and human cryptosporidiosis should be investigated in further molecular epidemiological studies in Mozambique.
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Affiliation(s)
- Augusto Messa
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
| | - Pamela C. Köster
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - Marcelino Garrine
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, 1349-008 Lisbon, Portugal
| | - Tacilta Nhampossa
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
- Instituto Nacional de Saúde, Ministério da Saúde, Marracuene, Maputo 1120, Mozambique
| | - Sérgio Massora
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
| | - Anélsio Cossa
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
| | - Quique Bassat
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
- ISGlobal, Hospital Clínic—Universitat de Barcelona, 08036 Barcelona, Spain
- ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
- Pediatric Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain
- Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| | - Karen Kotloff
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201-1509, USA; (K.K.); (M.M.L.)
| | - Myron M. Levine
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201-1509, USA; (K.K.); (M.M.L.)
| | - Pedro L. Alonso
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
- ISGlobal, Hospital Clínic—Universitat de Barcelona, 08036 Barcelona, Spain
- Global Malaria Program, World Health Organization, 1211 Geneva, Switzerland
| | - David Carmena
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - Inácio Mandomando
- Centro de Investigação em Saúde de Manhiça, Maputo 1929, Mozambique; (A.M.J.); (M.G.); (T.N.); (S.M.); (A.C.); (Q.B.); (P.L.A.)
- Instituto Nacional de Saúde, Ministério da Saúde, Marracuene, Maputo 1120, Mozambique
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Molecular Epidemiology of Human Cryptosporidiosis in Low- and Middle-Income Countries. Clin Microbiol Rev 2021; 34:34/2/e00087-19. [PMID: 33627442 DOI: 10.1128/cmr.00087-19] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Cryptosporidiosis is one of the most important causes of moderate to severe diarrhea and diarrhea-related mortality in children under 2 years of age in low- and middle-income countries. In recent decades, genotyping and subtyping tools have been used in epidemiological studies of human cryptosporidiosis. Results of these studies suggest that higher genetic diversity of Cryptosporidium spp. is present in humans in these countries at both species and subtype levels and that anthroponotic transmission plays a major role in human cryptosporidiosis. Cryptosporidium hominis is the most common Cryptosporidium species in humans in almost all the low- and middle-income countries examined, with five subtype families (namely, Ia, Ib, Id, Ie, and If) being commonly found in most regions. In addition, most Cryptosporidium parvum infections in these areas are caused by the anthroponotic IIc subtype family rather than the zoonotic IIa subtype family. There is geographic segregation in Cryptosporidium hominis subtypes, as revealed by multilocus subtyping. Concurrent and sequential infections with different Cryptosporidium species and subtypes are common, as immunity against reinfection and cross protection against different Cryptosporidium species are partial. Differences in clinical presentations have been observed among Cryptosporidium species and C. hominis subtypes. These observations suggest that WASH (water, sanitation, and hygiene)-based interventions should be implemented to prevent and control human cryptosporidiosis in low- and middle-income countries.
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Ahmadpour E, Safarpour H, Xiao L, Zarean M, Hatam-Nahavandi K, Barac A, Picot S, Rahimi MT, Rubino S, Mahami-Oskouei M, Spotin A, Nami S, Baghi HB. Cryptosporidiosis in HIV-positive patients and related risk factors: A systematic review and meta-analysis. ACTA ACUST UNITED AC 2020; 27:27. [PMID: 32351207 PMCID: PMC7191976 DOI: 10.1051/parasite/2020025] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 04/09/2020] [Indexed: 11/28/2022]
Abstract
Cryptosporidium is one of the major causes of diarrhea in HIV-positive patients. The aim of this study is to systematically review and meta-analyze the prevalence of Cryptosporidium in these patients. PubMed, Science Direct, Google Scholar, Web of Science, Cochrane and Ovid databases were searched for relevant studies dating from the period of 1 January 2000 to 31 December 2017. Data extraction for the included studies was performed independently by two authors. The overall pooled prevalence was calculated and subgroup analysis was performed on diagnostic methods, geographical distribution and study population. Meta-regression was performed on the year of publication, proportion of patients with diarrhea, and proportion of patients with CD4 < 200 cells/mL. One hundred and sixty-one studies and 51,123 HIV-positive participants were included. The overall pooled prevalence of Cryptosporidium infection in HIV-positive patients was 11.2% (CI95%: 9.4%–13.0%). The pooled prevalence was estimated to be 10.0% (CI95%: 8.4%–11.8%) using staining methods, 13.5% (CI95%: 8.9%–19.8%) using molecular methods, and 26.3% (CI95%: 15.0%–42.0%) using antigen detection methods. The prevalence of Cryptosporidium in HIV patients was significantly associated with the country of study. Also, there were statistical differences between the diarrhea, CD4 < 200 cells/mL, and antiretroviral therapy risk factors with Cryptosporidiosis. Thus, Cryptosporidium is a common infection in HIV-positive patients, and safe water and hand-hygiene should be implemented to prevent cryptosporidiosis occurrence in these patients.
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Affiliation(s)
- Ehsan Ahmadpour
- Research Center for Evidence Based Medicine (RCEBM), Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran - Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran
| | - Hanie Safarpour
- Student Research Committee, Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran
| | - Lihua Xiao
- College of Veterinary Medicine, South China Agricultural University, 510642 Guangzhou, China
| | - Mehdi Zarean
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, 91779-48964 Mashhad, Iran
| | | | - Aleksandra Barac
- Clinic for Infectious and Tropical Diseases, Clinical Centre of Serbia, 11000 Belgrade, Serbia
| | - Stephane Picot
- University Lyon, ICBMS UMR 5246 CNRS-INSA-CPE & Institute of Parasitology and Medical Mycology, Croix-Rousse Hospital, Hospices Civils de Lyon, 69004 Lyon, France
| | - Mohammad Taghi Rahimi
- Center for Health Related Social and Behavioral Sciences Research, Shahroud University of Medical Sciences, 36147-73947 Shahroud, Iran
| | - Salvatore Rubino
- Department of Biomedical Sciences, University of Sassari, 07100 Sardinia, Italy
| | - Mahmoud Mahami-Oskouei
- Department of Parasitology and Mycology, Faculty of Medicine, Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran
| | - Adel Spotin
- Immunology Research Center, Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran
| | - Sanam Nami
- Drug Applied Research Center, Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran
| | - Hossein Bannazadeh Baghi
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, 5166-15731 Tabriz, Iran
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King P, Tyler KM, Hunter PR. Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation: a systematic review and meta-analysis. Parasit Vectors 2019; 12:16. [PMID: 30621759 PMCID: PMC6323761 DOI: 10.1186/s13071-018-3263-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 12/12/2018] [Indexed: 12/14/2022] Open
Abstract
Background Globally cryptosporidiosis is one of the commonest causes of mortality in children under 24 months old and may be associated with important longterm health effects. Whilst most strains of Cryptosporidium parvum are zoonotic, C. parvum IIc is almost certainly anthroponotic. The global distribution of this potentially important emerging infection is not clear. Methods We conducted a systematic review of papers identifying the subtype distribution of C. parvum infections globally. We searched PubMed and Scopus using the following key terms Cryptospor* AND parvum AND (genotyp* OR subtyp* OR gp60). Studies were eligible for inclusion if they had found C. parvum within their human study population and had subtyped some or all of these samples using standard gp60 subtyping. Pooled analyses of the proportion of strains being of the IIc subtype were determined using StatsDirect. Meta-regression analyses were run to determine any association between the relative prevalence of IIc and Gross Domestic Product, proportion of the population with access to improved drinking water and improved sanitation. Results From an initial 843 studies, 85 were included in further analysis. Cryptosporidium parvum IIc was found in 43 of these 85 studies. Across all studies the pooled estimate of relative prevalence of IIc was 19.0% (95% CI: 12.9–25.9%), but there was substantial heterogeneity. In a meta-regression analysis, the relative proportion of all C. parvum infections being IIc decreased as the percentage of the population with access to improved sanitation increased and was some 3.4 times higher in those studies focussing on HIV-positive indivduals. Conclusions The anthroponotic C. parvum IIc predominates primarily in lower-income countries with poor sanitation and in HIV-positive individuals. Given the apparent enhanced post-infectious virulence of the other main anthroponotic species of Cryptosporidium (C. hominis), it is important to learn about the impact of this subtype on human health. Electronic supplementary material The online version of this article (10.1186/s13071-018-3263-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Philippa King
- The Norwich Medical School, University of East Anglia, Norwich, UK
| | - Kevin M Tyler
- The Norwich Medical School, University of East Anglia, Norwich, UK.
| | - Paul R Hunter
- The Norwich Medical School, University of East Anglia, Norwich, UK. .,Department of Environmental Health, Tshwane University of Technology, Pretoria, South Africa.
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Ayinmode AB, Oliveira BCM, Obebe OO, Dada-Adgebola HO, Ayede AI, Widmer G. Genotypic Characterization of Cryptosporidium Species in Humans and Peri-Domestic Animals in Ekiti and Oyo States, Nigeria. J Parasitol 2018; 104:639-644. [PMID: 30207199 DOI: 10.1645/17-74] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Cryptosporidiosis is one of the leading causes of diarrhea in humans and several other vertebrate species. Because surveys of Cryptosporidium genotypes from animals and humans living in the same region are rare, our understanding of the importance of zoonotic transmission in the epidemiology of cryptosporidiosis remains superficial. PCR was used to amplify a portion of the Cryptosporidium 18S small subunit ribosomal RNA gene from fecal DNA from humans and livestock living in Ekiti and Oyo states, Nigeria. PCR-positive samples were further analyzed using PCR targeting the heat-shock protein HSP-70, the actin, and the sporozoite glycoprotein gene gp60. A questionnaire was used to collect demographic information. Sixteen of 187 samples collected were Cryptosporidium 18S PCR positive. Of these, 5 samples originating from HIV-positive patients, 5 from otherwise healthy children, 2 from chickens, 3 from goats, and 1 from a dog were positive for at least 1 marker. Sequencing of the 18S rRNA amplicons revealed the presence of Cryptosporidium parvum in 2 HIV positive patients and in a child; the actin sequence confirmed the presence of this species. Two samples of HIV-positive patients amplified Cryptosporidium hominis 18S rRNA, one of them confirmed by the HSP-70, actin, and gp60 sequences. Cryptosporidium meleagridis was found in another HIV patient, while C. hominis was detected in 3 children (of which 2 were confirmed by gp60). Cryptosporidium muris was found in 1 child. In birds, we found C. meleagridis and, significantly, C. parvum, whereas we detected C. parvum and C. muris in 1 goat each. The only dog sampled was positive for Cryptosporidium canis. We conclude that, in the environment we surveyed, humans and animals are a potential part of the same transmission cycle. Measures to prevent zoonotic transmission should therefore be considered to reduce the prevalence of cryptosporidiosis.
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Affiliation(s)
- A B Ayinmode
- 1 Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine, University of Ibadan, Nigeria 200284.,2 Centre for Control and Prevention of Zoonoses, University of Ibadan, Nigeria 200284.,* These authors contributed equally to this work
| | - B C M Oliveira
- 3 Cummings School of Veterinary Medicine at Tufts University, 200 Westboro Road, North Grafton, Massachusetts 01536.,4 Universidade Estadual Paulista (UNESP), Faculdade de Medicina Veterinária, Araçatuba, 16050-680 Brazil.,* These authors contributed equally to this work
| | - O O Obebe
- 1 Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine, University of Ibadan, Nigeria 200284
| | - H O Dada-Adgebola
- 5 Department of Medical Microbiology and Parasitology, University College Hospital, Ibadan, Nigeria 200212
| | - A I Ayede
- 6 Department of Paediatrics, University College Hospital, Ibadan, Nigeria, 200212
| | - G Widmer
- 3 Cummings School of Veterinary Medicine at Tufts University, 200 Westboro Road, North Grafton, Massachusetts 01536
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Squire SA, Ryan U. Cryptosporidium and Giardia in Africa: current and future challenges. Parasit Vectors 2017; 10:195. [PMID: 28427454 PMCID: PMC5397716 DOI: 10.1186/s13071-017-2111-y] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 03/24/2017] [Indexed: 12/15/2022] Open
Abstract
Cryptosporidium and Giardia are important causes of diarrhoeal illness. Adequate knowledge of the molecular diversity and geographical distribution of these parasites and the environmental and climatic variables that influence their prevalence is important for effective control of infection in at-risk populations, yet relatively little is known about the epidemiology of these parasites in Africa. Cryptosporidium is associated with moderate to severe diarrhoea and increased mortality in African countries and both parasites negatively affect child growth and development. Malnutrition and HIV status are also important contributors to the prevalence of Cryptosporidium and Giardia in African countries. Molecular typing of both parasites in humans, domestic animals and wildlife to date indicates a complex picture of both anthroponotic, zoonotic and spill-back transmission cycles that requires further investigation. For Cryptosporidium, the only available drug (nitazoxanide) is ineffective in HIV and malnourished individuals and therefore more effective drugs are a high priority. Several classes of drugs with good efficacy exist for Giardia, but dosing regimens are suboptimal and emerging resistance threatens clinical utility. Climate change and population growth are also predicted to increase both malnutrition and the prevalence of these parasites in water sources. Dedicated and co-ordinated commitments from African governments involving "One Health" initiatives with multidisciplinary teams of veterinarians, medical workers, relevant government authorities, and public health specialists working together are essential to control and prevent the burden of disease caused by these parasites.
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Affiliation(s)
- Sylvia Afriyie Squire
- School of Veterinary and Life Sciences, Murdoch University, Perth, Australia
- Council for Scientific and Industrial Research, Animal Research Institute, Accra, Ghana
| | - Una Ryan
- School of Veterinary and Life Sciences, Murdoch University, Perth, Australia
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