Cross-Reactivity of Some Cryptosporidium Species with Cryptosporidium parvum Coproantigen in a Commercial ELISA Kit

To obtain information about the prevalence of Cryptosporidium parvum in cattle in Oyo State, Nigeria, a commercially available enzyme-linked immunosorbent assay (ELISA) kit made from Cryptosporidium-specificantibodies raised against antigens of Cryptosporidium parvum was used to screen 406 randomly collected fecal samples from cattle in four White Fulani herds. The overall prevalence was 32.3% (131/406) with 44 % (37/84), 36.5% (35/96) and 26.1% (59/226) prevalence in ages 12 months respectively. Further analysis of some of the ELISA-positive samples using nested polymerase chain reaction-restriction fragment length polymorphism (PCR– RFLP) and DNA sequencing of the small subunit (18S) rRNA gene identified the isolates asCryptosporidium bovis and C. ryanae. The use of molecular tools showed that there is crossreactivity between C. bovis and C. ryanae with theCryptosporidium-specific antibodies raised against antigens of Cryptosporidium parvum, thereby eliminating the false alarm about the possible risk of zoonotic transmission in the study area. This work showed that unlike some other livestock diseases where commercially available ELISA kits are often relied on as diagnostic tools, ELISA kits obtainedfrom Cryptosporidium-specific antibodies are not reliable for assessing risk of zoonosis in epidemiological studies

Prevalence of Gastrointestinal Parasites of Rodents in Ibadan, Nigeria

No Abstract

Cryptosporidium infection in cattle in Ogun state, Nigeria

The prevalence of Cryptosporidium spp. in cattle faeces in Ogun state, Nigeria was determined by a commercially produced enzyme-linked immunosorbent assay kit. Out of a total of 200 samples, 37.5% were positive for Cryptosporidium coproantigens. The highest rate of infection (78.1%) was observed in calves up to 3 months of age while adult cattle over 4 years of age had the lowest rate of infection (25.0%). There were significant differences (p<0.05) between the infection rates of the different age groups of cattle sampled. There was however no significant difference (p>0.05) between the infection rates in males (41.2%) and females (33.6%). Furthermore, the infection rate in diarrhoeic cattle (43.2%) was not significantly higher (p>0.05) than in non-diarrhoeic cattle (32.4%). The result of the study showed that the prevalence of cryptosporidiosis is high in cattle in southwestern part of Nigeria with calves being at the highest risk.Keywords: Cattle, Cryptosporidium, ELISA,Ogun state Nigeria

Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis

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

Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis

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

Identification and Characterization of Microsporidia from Fecal Samples of HIV-Positive Patients from Lagos, Nigeria

BACKGROUND: Microsporidia are obligate intracellular parasites that infect a broad range of vertebrates and invertebrates. They have been increasingly recognized as human pathogens in AIDS patients, mainly associated with a life-threatening chronic diarrhea and systemic disease. However, to date the global epidemiology of human microsporidiosis is poorly understood, and recent data suggest that the incidence of these pathogens is much higher than previously reported and may represent a neglected etiological agent of more common diseases indeed in immunocompetent individuals. To contribute to the knowledge of microsporidia molecular epidemiology in HIV-positive patients in Nigeria, the authors tested stool samples proceeding from patients with and without diarrhea. METHODOLOGY/PRINCIPAL FINDINGS: Stool samples from 193 HIV-positive patients with and without diarrhea (67 and 126 respectively) from Lagos (Nigeria) were investigated for the presence of microsporidia and Cryptosporidium using Weber's Chromotrope-based stain, Kinyoun stain, IFAT and PCR. The Weber stain showed 45 fecal samples (23.3%) with characteristic microsporidia spores, and a significant association of microsporidia with diarrhea was observed (O.R. = 18.2; CI: 95%). A similar result was obtained using Kinyoun stain, showing 44 (31,8%) positive samples with structures morphologically compatible with Cryptosporidium sp, 14 (31.8%) of them with infection mixed with microsporidia. The characterization of microsporidia species by IFAT and PCR allowed identification of Enterocytozoon bieneusi, Encephalitozoon intestinalis and E. cuniculi in 5, 2 and 1 samples respectively. The partial sequencing of the ITS region of the rRNA genes showed that the three isolates of E.bieneusi studied are included in Group I, one of which bears the genotype B. CONCLUSIONS/SIGNIFICANCE: To our knowledge, this is the first report of microsporidia characterization in fecal samples from HIV-positive patients from Lagos, Nigeria. These results focus attention on the need to include microsporidial diagnosis in the management of HIV/AIDS infection in Nigeria, at the very least when other more common pathogens have not been detected

Neospora caninum Infection in Nigeris: Evidence of Occurrence in Imported and Native Breeds of Cattle

Neospora caninum is a protozoan parasite causing significant economic losses due to abortions, birth of weak calves, fertility problems, reduced milk production and increased culling. The objective of this study was to investigate the presence of Neospora caninum in cattle imported to Nigeria for dairy purpose and also in the native breeds through the detection of antibodies (IgG) by Enzyme linked immunosorbent assay. Serum samples were collected from 600 cattle (100 Friesian and 500 native) in Nigeria. The seroprevalence of antibodies to N. caninum was 4% and 2.8% in the imported and native breeds respectively. This study provides the first serological evidence of the presence of N. caninum infection in both imported and native breeds of cattle in Nigeria. While more herd-based sero-epidemiological studies are needed to ascertain the extent of the infection in Nigeria, it is important to screen cattle for neosporosis before importation. The disease should be considered as a differential diagnosis in all cases of abortion in cattle.Keywords: Neospora caninum; Nigeria; abortion; Friesian cattle; native cattle

Occurrence Of Cryptosporidium Species Copro-Antigen In Asymptomatic Cattle.

A total of 341 faecal samples were collected from randomly selected cattle without diarrhea from Oyo state, south western Nigeria. Samples were classified based on age range: less than 6 months of age (69), between 7-12 months (71) and greater than 1 year old (191). Each sample was tested for the presence of Cryptosporidium sp copro-antigens using a commercially available enzyme-linked immunosorbent assays kit coated with Cryptosporidium-specific (monoclonal) antibodies raised against antigens of Cryptosporidium parvum. The overall prevalence of Cryptosporidium antigens in the sample was 28.1% (96/341). The prevalence (46.3%) was significantly higher in calves < 6 months than (29.6%) in ages 6 -12 months (P = 0.0408) and (22.5%) in cattle greater than 12 months (P=0.002). Calves < 6 months were twice at risk of being infected than 6 – 12 months old (OR: 2.059; 95%CI: 1.0 - 4.1) and 12 months old (OR: 2.977; 95%CI: 1.7 - 5.3) respectively. In conclusion, the present study is the first to demonstrate the presence of Cryptosporidium species antigen in bovine faecal samples from Nigeria and also clearly reveals that Cryptosporidium sp. is prevalent in non-diarrhoiec cattle. Therefore non-diarrhoeic cattle as well as diarrhoeic ones should be considered in the design of control measures to reduce the risk of transmission of the dieases to other animals and humans.Keywords: Cryptosporidium; diarrhoeic; non-diarrhoeic, Cattle; copro-antigen; humansUn total de 341 échantillons de matières fécales ont été prélevés auprès des bovins ne présentant pas de diarrhée et sélectionnés au hasard, dans l’État d’Oyo, au sud-ouest du Nigeria. Les échantillons ont été classés en fonction de la tranche d’âge: - moins de 6 mois d’âge (69), entre 7-12 mois (71) et plus de 1 an (191). Chaque échantillon a été testé pour identifier la présence de copro-antigènes Cryptosporidium sp. à l’aide d’un kit d’essai d’immuno-absorption disponible dans le commerce pour les essais recouvert d’enzyme Cryptosporidium spécifiques (anticorps monoclonal) dirigés contre des antigènes de Cryptosporidium parvum. La prévalence globale des antigènes de Cryptosporidium dans l’échantillon était de 28,1% (96/341). La prévalence chez les veaux de moins de 6 mois (46,3%) était significativement plus élevée que celle observée (29,6%) chez ceux âgées de 6 à 12 mois (P = 0,0408) et celle de (22,5%) chez les boeufs de plus de 12 mois (P = 0,002). Les veaux de moins de six mois

Field Evaluation of Immunogenicity of Five Commercial Vaccines Against Newcastle Disease in Poultry Farms in Ibadan, Nigeria

This study was conducted to evaluate immunogenicity of five commonly used vaccines for prevention of Newcastle disease (ND) in Ibadan, the capital city of Oyo State Nigeria. Two hundred and twenty (220) blood samples were collected from apparently healthy vaccinated chickenin 8 poultry farms in suburbs of the city. An average of 27 samples was collected from each farm.Blood samples were collected from a total of 72 breeders 88 layers and 60 pullets. Sera were testedusing heamagglutination inhibition (HI) techniquet to determineantibody levels against ND after vaccination with a commercial ND vaccine. Geometric mean titre (GMT) of antibodies against ND were calculated among flocks. The resultsindicated significant (p&lt;0.05) difference between the vaccines used. Highest level of immunity was confered by an imported LaSota vaccine (VAC 2),while lowest immunity was confered by another imported LaSota vaccine (VAC 1).The present findings indicate that some imported ND vaccines may effectively serve as alternative to the locally produced vaccines. Routine sero-monitoring ofpoultry response to ND vaccinesis advocated to enable farmers monitor immune profile of their flocks may contribute to more effective and efficient control of ND and ensure economic performance of farms. This facility could be part of the services in State Veterinary Laboratories in Nigeria. Keywords: Hemaglutination-inhibition test, Newcastle disease, seromonitoring, vaccine efficacyNigerian Veterinary Journal, VOL:33 (2) 475-48