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Ahmed SA, Kotepui M, Masangkay FR, Milanez GD, Karanis P. Gastrointestinal parasites in Africa: A review. ADVANCES IN PARASITOLOGY 2023; 119:1-64. [PMID: 36707173 DOI: 10.1016/bs.apar.2022.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Data on human gastrointestinal parasites (GIP) infections in the african sub-regions and countries are mainly lacking in terms of prevalence and population stratification by afflicted age group, symptomatology, multi-parasitism, and diagnostic methods. This study aims to describe the GIP reported in african countries and discuss the extent of the burden in the african context. Only 68.42% (39/57) of african countries reported human cases of GIP with helminths (45%, CI: 40-50%, I2: 99.79%) as the predominant parasitic group infecting the african population. On a regional scale, Central Africa had the highest pooled prevalence for GIP (43%, CI: 32-54%, I2: 99.74%), while the Central African Republic led all countries with a pooled prevalence of 90% (CI: 89-92%, I2: 99.96%). The vulnerable population (patients who are minorities, children, old, poor, underfunded, or have particular medical conditions) was the most affected (50%, CI: 37-62%, I2: 99.33%), with the predominance of GIP in the 6 to <20 years age group (48%, CI: 43-54%, I2: 99.68%). Reports on multi-parasitism (44%, CI: 40-48%, I2: 99.73%) were almost double the reports of single infections (43%, CI: 27-59%, I2: 99.77%) with combined molecular and non-molecular techniques demonstrating the best performance for GIP identification. The current review spans more than 40 years of GIP reports from the african continent. Geographical characteristics, environmental factors, habits of its inhabitants, and their health status play a crucial role in GIP modulation and behaviour in its captive hosts. Strategies for regular and enhanced surveillance, policy formation, and high-level community awareness are necessary to identify the true incidence in Africa and the transmission of the pathogens via water and food.
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Affiliation(s)
- Shahira A Ahmed
- Department of Parasitology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Manas Kotepui
- Medical Technology Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand
| | - Frederick R Masangkay
- Department of Medical Technology, Faculty of Pharmacy, University of Santo Tomas, Manila, Philippines
| | - Giovanni D Milanez
- Department of Medical Technology, Faculty of Pharmacy, University of Santo Tomas, Manila, Philippines
| | - Panagiotis Karanis
- University of Cologne, Medical Faculty and University Hospital, Cologne, Germany; University of Nicosia Medical School, Nicosia, Cyprus.
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Krumkamp R, Aldrich C, Maiga-Ascofare O, Mbwana J, Rakotozandrindrainy N, Borrmann S, Caccio SM, Rakotozandrindrainy R, Adegnika AA, Lusingu JPA, Amuasi J, May J, Eibach D. Transmission of Cryptosporidium Species Among Human and Animal Local Contact Networks in Sub-Saharan Africa: A Multicountry Study. Clin Infect Dis 2021; 72:1358-1366. [PMID: 32150243 PMCID: PMC8075035 DOI: 10.1093/cid/ciaa223] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 03/03/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Cryptosporidiosis has been identified as one of the major causes of diarrhea and diarrhea-associated deaths in young children in sub-Saharan Africa. This study traces back Cryptosporidium-positive children to their human and animal contacts to identify transmission networks. METHODS Stool samples were collected from children < 5 years of age with diarrhea in Gabon, Ghana, Madagascar, and Tanzania. Cryptosporidium-positive and -negative initial cases (ICs) were followed to the community, where stool samples from households, neighbors, and animal contacts were obtained. Samples were screened for Cryptosporidium species by immunochromatographic tests and by sequencing the 18S ribosomal RNA gene and further subtyped at the 60 kDa glycoprotein gene (gp60). Transmission clusters were identified and risk ratios (RRs) calculated. RESULTS Among 1363 pediatric ICs, 184 (13%) were diagnosed with Cryptosporidium species. One hundred eight contact networks were sampled from Cryptosporidium-positive and 68 from negative ICs. Identical gp60 subtypes were detected among 2 or more contacts in 39 (36%) of the networks from positive ICs and in 1 contact (1%) from negative ICs. In comparison to Cryptosporidium-negative ICs, positive ICs had an increased risk of having Cryptosporidium-positive household members (RR, 3.6 [95% confidence interval {CI}, 1.7-7.5]) or positive neighboring children (RR, 2.9 [95% CI, 1.6-5.1]), but no increased risk of having positive animals (RR, 1.2 [95% CI, .8-1.9]) in their contact network. CONCLUSIONS Cryptosporidiosis in rural sub-Saharan Africa is characterized by infection clusters among human contacts, to which zoonotic transmission appears to contribute only marginally.
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Affiliation(s)
- Ralf Krumkamp
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research, Hamburg-Lübeck-Borstel-Riems, Germany
| | - Cassandra Aldrich
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research, Hamburg-Lübeck-Borstel-Riems, Germany.,Division of Infectious Diseases and Tropical Medicine, University Hospital, Ludwig Maximilian University of Munich, Munich, Germany
| | - Oumou Maiga-Ascofare
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research, Hamburg-Lübeck-Borstel-Riems, Germany.,Kumasi Centre for Collaborative Research in Tropical Medicine, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Joyce Mbwana
- National Institute for Medical Research, Tanga Research Centre, Tanga, United Republic of Tanzania
| | | | - Steffen Borrmann
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin and German Center for Infection Research, partner site Tübingen, Universitätsklinikum, Tübingen, Germany
| | - Simone M Caccio
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | | | - Ayola Akim Adegnika
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.,Institut für Tropenmedizin and German Center for Infection Research, partner site Tübingen, Universitätsklinikum, Tübingen, Germany
| | - John P A Lusingu
- National Institute for Medical Research, Tanga Research Centre, Tanga, United Republic of Tanzania
| | - John Amuasi
- Kumasi Centre for Collaborative Research in Tropical Medicine, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Jürgen May
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research, Hamburg-Lübeck-Borstel-Riems, Germany
| | - Daniel Eibach
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,German Center for Infection Research, Hamburg-Lübeck-Borstel-Riems, Germany
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Karshima SN, Karshima MN. Epidemiology of Cryptosporidium Infections among People Living with HIV/AIDS in Nigeria: Results of Systematic Review and Meta-analysis. Acta Parasitol 2021; 66:60-74. [PMID: 32683583 DOI: 10.1007/s11686-020-00253-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/06/2020] [Indexed: 12/18/2022]
Abstract
PURPOSE Cryptosporidium is implicated in diarrhea epidemics in many parts of the world and is said to be the most common protozoan cause of diarrhea among people living with HIV/AIDS (PLWHA) globally. To provide data on the burden of Cryptosporidium infections among Nigerians living with HIV/AIDS, we reported the prevalence, geographic distribution and Cryptosporidium species diversity among this population in Nigeria. METHODS We used the PRISMA guidelines to perform a systematic review and meta-analysis of articles published between January 1, 1995 and April 21, 2020. Pooled estimate (PE), heterogeneity, quality of each study and publication bias were determined using the random-effects model, Cochran's Q test, the 9 point Joanna Briggs Institute Critical Appraisal Instrument and the Egger's regression asymmetry test, respectively. RESULTS Forty-six articles reported 2612 positive cases of Cryptosporidium infections from 12,756 PLWHA examined in 20 Nigerian States and the Federal Capital Territory. Overall pooled estimate was 14.5% (95% CI 10.4-19.9) with a range of 0.3% (95% CI 0.0-1.8) to 43.7% (95% CI 35.6-52.3) across sub-groups, with the PEs in relation to CD4+ T cell count, species and age showing significant variations at p < 0.05. Cryptosporidium hominis was the most prevalent (3.5%, 95% CI 2.3-5.2) of the six Cryptosporidium species reported in Nigeria. CONCLUSION Cryptosporidium infections are moderately prevalent among PLWHA in Nigeria with the highest regional prevalence in the north-east. In addition to personal hygienic practices, the inclusion of Cryptosporidium screening as part of HIV/AIDS clinics in Nigeria will reduce the burden of the parasite among PLWHA in Nigeria.
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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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First identification of genotypes of Enterocytozoon bieneusi (Microsporidia) among symptomatic and asymptomatic children in Mozambique. PLoS Negl Trop Dis 2020; 14:e0008419. [PMID: 32603325 PMCID: PMC7357779 DOI: 10.1371/journal.pntd.0008419] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 07/13/2020] [Accepted: 05/23/2020] [Indexed: 11/19/2022] Open
Abstract
Enterocytozoon bieneusi is a human pathogen with a broad range of animal hosts. Initially, E. bieneusi was considered an emerging opportunistic pathogen in immunocompromised, mainly HIV-infected patients, but it has been increasingly reported in apparently healthy individuals globally. As in other African countries, the molecular epidemiology of E. bieneusi in Mozambique remains completely unknown. Therefore, we undertook a study to investigate the occurrence and genetic diversity of E. bieneusi infections in children with gastrointestinal symptoms as well as in asymptomatic children in Mozambique. Individual stool specimens were collected from 1,247 children aged between 0 and 14 years-old living in urban and rural settings in Zambézia (n = 1,097) and Maputo (n = 150) provinces between 2016 and 2019. Samples were analysed for E. bieneusi by nested-PCR targeting the internal transcribed spacer (ITS) region of the rRNA gene. All positive amplicons were confirmed and genotyped. Penalised logistic regression (Firth) was used to evaluate risk associations. The overall prevalence of E. bieneusi in this children population was 0.7% (9/1,247). A 10-fold higher prevalence was found in Maputo (4.0%; 6/150) than in Zambézia (0.3%; 3/1,097). All E. bieneusi-positive samples were from children older than 1-year of age, and most (8/9) from asymptomatic children. Nucleotide sequence analysis of the ITS region revealed the presence of four genotypes, three previously reported (Peru11, n = 1; Type IV, n = 2, and S2, n = 2) and a novel genotype (named HhMzEb1, n = 4). Novel genotype HhMzEb1 was identified in both asymptomatic (75%, 3/4) and symptomatic (25%, 1/4) children from a rural area in Maputo province in southern Mozambique. Genotypes HhMzEb1, Peru11, S2, and Type IV belonged to the Group 1 that includes genotypes with low host specificity and the potential for zoonotic and cross-species transmission. Being infected by enteric protozoan parasites and no handwashing were identified as risk associations for E. bieneusi infection. This study reports the first investigation of E. bieneusi genotypes in Mozambique with the identification of three previously reported genotypes in humans as well as a novel genotype (HhMzEb1). Findings highlight the need to conduct additional research to elucidate the epidemiology of E. bieneusi in the country, especially in rural areas where poor hygiene conditions still prevail. Special attention should be paid to the identification of suitable animal and environmental reservoirs of this parasite and to the characterization of transmission pathways.
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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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Karimi K, Mirjalali H, Niyyati M, Haghighi A, Pourhoseingholi MA, Sharifdini M, Naderi N, Zali MR. Molecular epidemiology of Enterocytozoon bieneusi and Encephalitozoon sp., among immunocompromised and immunocompetent subjects in Iran. Microb Pathog 2020; 141:103988. [PMID: 31972268 DOI: 10.1016/j.micpath.2020.103988] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 01/18/2020] [Accepted: 01/19/2020] [Indexed: 12/31/2022]
Abstract
Intestinal microsporidiosis is known as an opportunistic infection in immunocompromised patients. The current study aimed to investigate intestinal microsporidia infection in human subjects with/without immunodeficiency. Totally, 600 stool samples were collected from immunocompromised (254) and immunocompetent (346) subjects. DNA extraction was performed and the SSU rRNA and the ITS genes were amplified to detect and characterize microsporidia and the relevant genotypes. Phylogenetic trees were drawn using MEGA7 software to illustrate the correlation between isolates. From 600 enrolled subjects, 283 and 317 were male and female, respectively. The average age ± SD of all tested subjects was 28.85 ± 26.92. The results of PCR demonstrated the presence of E. bieneusi and Encephalitozoon sp., among 10/600 (1.67%) and 26/600 (4.33%) of samples, respectively. Accordingly, E. bieneusi was seen among 4/346 (1.15%), 1/53 (1.88%), 3/124 (2.42%), and 2/63 (3.17%), and Encephalitozoon sp., was detected from 17/346 (4.91%), 3/53 (5.36%), 4/124 (3.22%) and 2/63 (3.17%) of healthy subjects, RA patients, cancer patients, and transplantation recipients, respectively. Statistical significant correlation was not seen between the presence of microsporidia and age, gender, stool appearance, and geographical region. Molecular analysis showed that all E. bieneusi were the genotype D. Phylogenetic tree demonstrated no classification according to the presence/absence of immunodeficiency, geographical locations and presence of diarrhea. The high prevalence of Encephalitozoon sp., in comparison to E. bieneusi in this study suggested the importance of this genus alongside with E. bieneusi in Iran. In addition, predominance of the genotype D highlighted the wide distribution of this genotype in Iran.
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Affiliation(s)
- Kambiz Karimi
- Department of Medical Parasitology and Mycology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hamed Mirjalali
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Maryam Niyyati
- Department of Medical Parasitology and Mycology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Ali Haghighi
- Department of Medical Parasitology and Mycology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohamad Amin Pourhoseingholi
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Meysam Sharifdini
- Department of Medical Parasitology and Mycology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Nosratollah Naderi
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Zali
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Prasertbun R, Mori H, Sukthana Y, Popruk S, Kusolsuk T, Hagiwara K, Mahittikorn A. "Enterocytozoon bieneusi and Cryptosporidium: a cross-sectional study conducted throughout Thailand". BMC Infect Dis 2019; 19:808. [PMID: 31521133 PMCID: PMC6744698 DOI: 10.1186/s12879-019-4422-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 08/29/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Enterocytozoon bieneusi and Cryptosporidium spp. are prevalent zoonotic parasites associated with a high burden among children. To date only limited molecular epidemiological data on E. bieneusi and Cryptosporidium spp. in humans living in Thailand has been published. METHODS PCR-based tools were used to detect and characterize E. bieneusi and Cryptosporidium spp. The internal transcribed spacer (ITS) region of the rRNA gene was used to investigate E. bieneusi, and the small subunit (SSU) rRNA gene was used to investigate Cryptosporidium spp., and 697 fecal samples from villagers and school children in rural areas in Thailand were analyzed. RESULTS The infection rates were 2.15% (15/697) for E. bieneusi and 0.14% (1/697) for Cryptosporidium spp. The prevalence of E. bieneusi was significantly high in Loei province. Sequence analysis indicated that the Cryptosporidium isolate was C. parvum. Nine E. bieneusi genotypes were identified, EbpC, Peru12, TMH6, TMH3, TMH7, H, D, and two novel genotypes TMLH1 and TMLH2. E. bieneusi prevalence was significantly higher in male participants than in female participants, and in children aged 3-15 years than in participants aged > 15 years. CONCLUSIONS The prevalence, genotypes, and zoonotic potential of E. bieneusi were found to vary significantly high even in one country. Transmission routes and key animal carriers of E. bieneusi may be associated with differences in hygiene, sanitation, and cultural behaviors. Further molecular studies including longitudinal studies will be required to unveil epidemiological characteristics of these opportunistic intestinal protozoa in all over the countries.
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Affiliation(s)
- Rapeepun Prasertbun
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Hirotake Mori
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Department of General Medicine, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Yaowalark Sukthana
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Supaluk Popruk
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Teera Kusolsuk
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Katsuro Hagiwara
- Department of Pathobiology, School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, Japan
| | - Aongart Mahittikorn
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
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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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Zhang XX, Jiang RL, Ma JG, Xu C, Zhao Q, Hou G, Liu GH. Enterocytozoon bieneusi in Minks ( Neovison vison) in Northern China: A Public Health Concern. Front Microbiol 2018; 9:1221. [PMID: 29946304 PMCID: PMC6005834 DOI: 10.3389/fmicb.2018.01221] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/18/2018] [Indexed: 11/13/2022] Open
Abstract
Enterocytozoon bieneusi is the most important causative agent of microsporidiosis and can infect almost all vertebrate and invertebrate hosts, including minks (Neovison vison). In the present study, a total of 298 feces samples (including 79 from Heilongjiang province, 31 from Hebei province, 67 from Jilin province, 90 from Liaoning province, and 31 from Shandong province, Northern China) were examined by nested PCR amplification of the internal transcribed spacer (ITS) region of the rRNA gene. The overall prevalence of E. bieneusi in minks was 10.1%, with 10.5% in Jilin province, 32.3% in Hebei province, 8.9% in Liaoning province, 0% in Shandong province, and 6.3% in Heilongjiang province. Furthermore, multiple logistic regression analysis revealed that region was only risk factors associated with E. bieneusi infection in the investigated minks. Five E. bieneusi ITS genotypes (three known genotypes, namely D, Peru11, and EbpC; two novel genotypes, namely, NCM-1 and NCM-2) were found in the current study. Importantly, genotypes D, Peru11 and EbpC, previously identified in humans, were also found in minks, which suggested that minks are the potential sources of human microsporidiosis. To the best of our knowledge, this is the first report of E. bieneusi infection in minks worldwide. The results of the present survey have implications for the controlling E. bieneusi infection in minks, other animals and humans.
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Affiliation(s)
- Xiao-Xuan Zhang
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, China
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Ruo-Lan Jiang
- School of Basic Medical Sciences, Xiangya School of Medicine, Central South University, Changsha, China
| | - Jian-Gang Ma
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Chao Xu
- Key Laboratory of Agricultural Ministry, State Key Laboratory of Special Economic Animal Molecular Biology, Institute of Special Animal and Plant Sciences of Chinese Academy of Agricultural Sciences, Changchun, China
| | - Quan Zhao
- College of Animal Science and Technology, Changchun Sci-Tech University, Changchun, China
| | - Guangyu Hou
- College of Basic Medicine, Mudanjiang Medical College, Mudanjiang, China
| | - Guo-Hua Liu
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, China
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12
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First detection of Cryptosporidium DNA in blood and cerebrospinal fluid of HIV-infected patients. Parasitol Res 2018; 117:875-881. [PMID: 29411108 DOI: 10.1007/s00436-018-5766-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 01/18/2018] [Indexed: 10/18/2022]
Abstract
Human cryptosporidiosis is an intestinal infection caused by different species belonging to the genus Cryptosporidium in both immunocompetent and immunocompromised individuals. The life cycle of Cryptosporidium sp. when affecting the digestive system is well known but the infection of other organs is less studied. Molecular methods are necessary for species and subtypes identification. The goal of this work is to propose a new approach that contributes to the diagnosis of the extra-intestinal dissemination process of Cryptosporidium infection. Cryptosporidium sp. was detected in stool and biopsy samples of two HIV-infected patients. DNA was extracted from feces, biopsy specimens, blood, and cerebrospinal fluid (CSF). All samples were analyzed by nested PCR-RFLP of the 18S rDNA, real-time PCR, and gp60 subtyping. Cryptosporidium DNA was detected in stool and tissue samples and it was also present in blood and CSF samples. Both cases were characterized as Cryptosporidium hominis subtype IeA11G3T3. This is the first report that demonstrates the presence of Cryptosporidium DNA in blood and CSF of HIV-infected patients.
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Wang ZD, Liu Q, Liu HH, Li S, Zhang L, Zhao YK, Zhu XQ. Prevalence of Cryptosporidium, microsporidia and Isospora infection in HIV-infected people: a global systematic review and meta-analysis. Parasit Vectors 2018; 11:28. [PMID: 29316950 PMCID: PMC5759777 DOI: 10.1186/s13071-017-2558-x] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/27/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Diarrhea caused by opportunistic intestinal protozoa is a common problem in HIV infection. We aimed to establish the prevalence of Cryptosporidium, misrosporidia, and Isospora in HIV-infected people using a systematic review and meta-analysis, which is central to developing public policy and clinical services. METHODS We searched PubMed, ScienceDirect, Google Scholar, Embase, Chinese Web of Knowledge, Wanfang, and Chongqing VIP databases for studies reporting Cryptosporidium, microsporidia, or Isospora infection in HIV-infected people. We extracted the numbers of people with HIV and protozoa infection, and estimated the pooled prevalence of parasite infection by a random effects model. RESULTS Our research identified 131 studies that reported Cryptosporidium, microsporidia, and Isospora infection in HIV-infected people. We estimated the pooled prevalence to be 14.0% (3283/43,218; 95% CI: 13.0-15.0%) for Cryptosporidium, 11.8% (1090/18,006; 95% CI: 10.1-13.4%) for microsporidia, and 2.5% (788/105,922; 95% CI: 2.1-2.9%) for Isospora. A low prevalence of microsporidia and Isospora infection was found in high-income countries, and a high prevalence of Cryptosporidium and Isospora infection was found in sub-Saharan Africa. We also detected a high prevalence of Cryptosporidium, microsporidia, and Isospora infection in patients with diarrhea. Sensitivity analysis showed that three studies significantly affect the prevalence of Isospora, which was adjusted to 5.0% (469/8570; 95% CI: 4.1-5.9%) by excluding these studies. CONCLUSIONS Our findings suggest that HIV-infected people have a high prevalence of Cryptosporidium, microsporidia, and Isospora infection in low-income countries and patients with diarrhea, especially in sub-Saharan Africa, reinforcing the importance of routine surveillance for opportunistic intestinal protozoa in HIV-infected people.
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Affiliation(s)
- Ze-Dong Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046 People’s Republic of China
| | - Quan Liu
- Military Veterinary Institute, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun, Jilin Province 130122 People’s Republic of China
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province 130188 People’s Republic of China
| | - Huan-Huan Liu
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province 130188 People’s Republic of China
| | - Shuang Li
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province 130188 People’s Republic of China
| | - Li Zhang
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province 130188 People’s Republic of China
| | - Yong-Kun Zhao
- Military Veterinary Institute, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun, Jilin Province 130122 People’s Republic of China
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046 People’s Republic of China
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Zhang Y, Koehler AV, Wang T, Haydon SR, Gasser RB. First detection and genetic characterisation of Enterocytozoon bieneusi in wild deer in Melbourne's water catchments in Australia. Parasit Vectors 2018; 11:2. [PMID: 29295716 PMCID: PMC5751821 DOI: 10.1186/s13071-017-2577-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/06/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Enterocytozoon bieneusi is reported to be a common microsporidian of humans and animals in various countries. However, E. bieneusi has yet to be recorded in animals in Australia. Here, we undertook the first molecular epidemiological investigation of E. bieneusi in three species of deer (Cervus elaphus, Dama dama and Rusa unicolor) that live in the catchment areas that supply the city of Melbourne with drinking water. METHODS Genomic DNA was extracted from a total of 610 individual faecal samples from wild deer, including sambar deer (Rusa unicolor) (n = 516), red deer (Cervus elaphus) (n = 77) and fallow deer (Dama dama) (n = 17) from nine catchment areas, and then tested using a nested PCR-based sequencing approach employing internal transcribed spacer (ITS) of nuclear ribosomal DNA as the genetic marker. RESULTS Enterocytozoon bieneusi was detected in 25 of all 610 (4.1%) samples exclusively in samples from sambar deer. The analysis of ITS sequence data revealed three known (D, J and Type IV) and two new (MWC_d1 and MWC_d2) genotypes of E. bieneusi. Although the significance of the latter two new genotypes is presently unknown, phylogenetic analysis of ITS sequence data sets showed that they cluster with genotypes D and Type IV, which have been recorded previously in humans. These findings suggest that sambar deer in the water catchments harbour zoonotic genotypes of E. bieneusi. CONCLUSIONS Further insight into the epidemiology of E. bieneusi in wildlife, water and the environment in Australia will be important to have an informed position on the public health significance of microsporidiosis caused by this microbe.
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Affiliation(s)
- Yan Zhang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010 Australia
| | - Anson V. Koehler
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010 Australia
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010 Australia
| | | | - Robin B. Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010 Australia
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Liu H, Jiang Z, Yuan Z, Yin J, Wang Z, Yu B, Zhou D, Shen Y, Cao J. Infection by and genotype characteristics of Enterocytozoon bieneusi in HIV/AIDS patients from Guangxi Zhuang autonomous region, China. BMC Infect Dis 2017; 17:684. [PMID: 29029610 PMCID: PMC5640944 DOI: 10.1186/s12879-017-2787-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 10/03/2017] [Indexed: 11/10/2022] Open
Abstract
Background Enterocytozoon bieneusi has been increasingly reported to infect humans and various mammals. Microsporidia cause diarrhea in HIV-infected patients worldwide. PCR amplification and sequencing based on the internal transcribed spacer region have been used to describe the genotypes of E. bieneusi and transmission of microsporidiosis. Methods In this study, we examined E. bieneusi infection and genotypes in HIV-positive patients in Guangxi, China. Stool specimens were collected from 285 HIV-positive patients and 303 HIV-negative individuals. E. bieneusi genotypes were characterized using nested PCR and sequencing. Results Thirty-three (11.58%) HIV-positive patients were infected with microsporidia, and no infection was found in the 303 healthy controls. Three new genotypes were identified and named as GX25, GX456, and GX458; four known genotypes, PigEBITS7, Type IV/K, D, and Ebpc, were also identified. Our data showed that the positive rate for microsporidia was significantly higher in the rural patients than in the other occupation groups. In addition, the positive rate for microsporidia was significantly higher in the patients who drink unboiled water than in those with other drinking water sources. Conclusions Our results will provide baseline data for preventing and controlling E. bieneusi infection in HIV/AIDS patients. Further studies are required to clarify the epidemiology and potential sources of microsporidia. Our study showed that microsporidium infection occurs in the HIV/AIDS patients in Guangxi, China. Electronic supplementary material The online version of this article (10.1186/s12879-017-2787-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hua Liu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, WHO Collaborating Center for Tropical Diseases, 207 Rui Jin Er Road, Shanghai, 200025, China
| | - Zhihua Jiang
- Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning, 530028, China
| | - Zhongying Yuan
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, WHO Collaborating Center for Tropical Diseases, 207 Rui Jin Er Road, Shanghai, 200025, China
| | - Jianhai Yin
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, WHO Collaborating Center for Tropical Diseases, 207 Rui Jin Er Road, Shanghai, 200025, China
| | - Zunfu Wang
- Guangxi Medical University, Nanning, 530021, China
| | - Bingxue Yu
- Guangxi Medical University, Nanning, 530021, China
| | - Dongsheng Zhou
- Affiliated Hospital of Guilin Medical University, Guilin, 541001, China
| | - Yujuan Shen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, WHO Collaborating Center for Tropical Diseases, 207 Rui Jin Er Road, Shanghai, 200025, China.
| | - Jianping Cao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, WHO Collaborating Center for Tropical Diseases, 207 Rui Jin Er Road, Shanghai, 200025, China.
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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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