SUMMARYBackground: Humans can get infected through direct or indirect contact with infective stages of zoonotic parasites shed to the environment through dog faeces. Objectives: This study was designed to investigate the presence of gastrointestinal parasites present in dog faeces shed on the street of Ibadan metropolis, one of the largest cities in Africa. Methods: Twenty-three locations were randomly selected using grid-sampling method. A total of 203 faecal samples collected from the streets of selected areas were processed for detection of helminth eggs and protozoan oocysts using flotation technique. Eggs/oocysts per gram of faeces was counted using modified McMaster technique. Results: The prevalence of gastrointestinal parasites was 43.3% (88/203). Single and multiple infections were 69 (78.4%) and 19 (21.6%) respectively. The parasites detected were Ancylostoma sp. 24.6% (50/88) Isospora sp. 14.2% (29/88), Toxocara sp. 9.8% (20/88), Uncinaria sp. 2.5% (5/88) and Strongyloides sp, 3.9% (8/88). Ancylostoma sp. (320 x 10 2 epg) and Uncinaria sp. (5 x 10 2 epg) had the highest and least intensity respectively. Streets within residential areas having markets had the highest number of positive samples. All the genera of parasites detected in this study have zoonotic potential. Conclusion:The high prevalence of zoonotic parasites detected in dog faeces from Ibadan metropolis showed that infected stray dogs roam the streets and constitute potential risk to human health. This study suggests the need for enforcement of laws restraining roaming or straying dogs and proper veterinary care of dogs.

Cryptosporidium and Enterocytozoon are common opportunistic pathogens in HIV+ patients in developing countries, especially those do not have access to antiretroviral therapy. To determine the distribution of genotypes/subtypes of Cryptosporidium and Enterocytozoon bieneusi, faecal specimens were collected from 132 HIV+ persons attending a tertiary hospital in Ibadan, Nigeria. By polymerase chain reaction, eight and ten patients were identified as positive for Cryptosporidium spp. and E. bieneusi, respectively. Seven of the Cryptosporidium specimens were identified as C. hominis, while the remaining one as the new species C. viatorum recently identified in the United Kingdom. DNA sequencing of the 60-kDa glycoprotein gene showed that the C. hominis belonged to three common subtype families: Ia (in three patients), Ib (in one patient) and Ie (in one patient). In contrast, DNA sequencing of the E. bieneusi internal transcribed spacer products showed the occurrence of genotypes associated with both humans (Peru 8 in one patient, Nig2 in two patients and a new genotype in one patient) and animals (D in one patient and Type IV in five patients). Low CD4+ cell count was identified as a risk factor for both cryptosporidiosis and microsporidiosis.

Most studies on the distribution of Cryptosporidium species in cattle were done with dairy breeds in industrialized nations. In this study, 65 fecal samples from randomly selected 12-24-week-old diarrheic calves in four white Fulani herds in southwestern Nigeria were screened for Cryptosporidium spp. using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the small subunit rRNA gene. Thirty-four (52.3%) of the samples were positive for Cryptosporidium. RFLP analysis of PCR products showed that 18 (27.7%) and five (7.7%) of the positive samples had Cryptosporidium bovis and Cryptosporidium ryanae, respectively, and 11 (16.9%) had mixed infections of the two species. The absence of C. parvum suggests that the age group of calves studied is not likely to be source of zoonotic infection to humans.

A study was conducted to detect and identify Cryptosporidium spp. in 43 children from Oyo State, Nigeria. Using nested polymerase chain reaction, 11.6% of the children were identified as positive for Cryptosporidium spp. Restriction fragment length polymorphism analysis and DNA sequencing of the PCR products showed the presence of three subtype families of Cryptosporidium hominis (two isolates of Ia and one isolate of Ib) and Cryptosporidium parvum (two isolates of IIc), all anthroponotic in nature. This study identified a high diversity of Cryptosporidium subtypes and clearly suggested that anthroponotic rather than zoonotic transmission played a more important role in the epidemiology of Cryptosporidium in the studied area.

A study was conducted to detect and identify enteric microsporidian species in 43 children from Oyo state, Nigeria. Using nested polymerase chain reaction, 9.3% of the children were identified as positive for Enterocytozoon bieneusi. DNA sequencing of the PCR products showed the presence of three known genotypes (two isolates of genotype D and one of genotype K) and one new genotype. This study suggests that either human or animal (or both) could be the infection source for the children, since identified genotypes D and K have been previously detected in both immunocompromised and immunocompetent patients and domestic animals. The identification of high diversity also suggests intensive transmission of microsporidiosis in the studied area.

Few data are available on the distribution and human infective potential of Cryptosporidium and Enterocytozoon bieneusi genotypes in bats. In this preliminary study, we collected 109 fecal specimens during April–July 2011 from a colony of straw-colored fruit bats (Eidolon helvum) in an urban park (Agodi Gardens) of Ibadan, Nigeria, and analyzed for Cryptosporidium spp., Giardia duodenalis and E. bieneusi using PCR targeting the small subunit rRNA gene, triosephosphate isomerase gene, and ribosomal internal transcribed spacer, respectively. Genotypes of these enteric parasites were determined by DNA sequencing of the PCR products. Altogether, 6 (5.5%), 0 and 16 (14.7%) specimens were positive for Cryptosporidium spp., G. duodenalis, and E. bieneusi, respectively. DNA sequence analysis of the PCR products indicated the presence of two novel Cryptosporidium genotypes named as bat genotype XIV (in 5 specimens) and bat genotype XV (in 1 specimen) and one known E. bieneusi genotype (Type IV in 1 specimen) and two novel E. bieneusi genotypes (Bat1 in 13 specimens and Bat2 in 2 specimens). In phylogenetic analysis of DNA sequences, the two novel Cryptosporidium genotypes were genetically related to Bat genotype II previously identified in fruit bats in China and Philippines, whereas the two novel E. bieneusi genotypes were genetically related to Group 5, which contains several known genotypes from primates. With the exception of Type IV, none of the Cryptosporidium and E. bieneusi genotypes found in bats in this study are known human pathogens. Thus, straw-colored fruit bats in Nigeria are mainly infected with host-adapted Cryptosporidium and E. bieneusi genotypes.

Background: Several zoonotic diseases are known to constitute great impediment to livestock management and production worldwide, especially in developing countries where control measures are largely non-existent. This study sets out to investigate the occurrence of toxoplasmosis, neosporosis and brucellosis among cattle herds in Oyo State, southwest Nigeria. Materials and Methods: A cross-sectional survey to screen for antibodies to Toxoplasma gondii, Neospora caninum and Brucella abortus was conducted among 174 cattle in 17 herds. Sera obtained from the cattle were screened for antibodies to Toxoplasma gondii and Neospora caninum using enzyme-linked immunosorbent assay (ELISA) and for Brucella abortus antibodies using Rose Bengal test and Competitive Enzyme Linked Immunosorbent Assay (cELISA). Results: Overall, herd level prevalence of 52.9%, 23.5% and 23.5% as well as individual prevalence of 7.5%, 3.4% and 3.4% was obtained for toxoplasmosis, neosporosis and brucellosis, respectively. Antibodies to T. gondii, N. caninum and B. abortus were detected in 2 of the 17 herds, T. gondii and N. caninum in 4 herds, and T. gondii and B. abortus in 4 herds. Statistically significant association was only found between seropositivity to T. gondii antibodies and sex (p<0.05). Conclusion: Our results showed that toxoplasmosis, neosporosis and brucellosis are prevalent among cattle herds screened in the study area. Considering the potential impact of these diseases on livestock management and production, extensive surveillance is necessary for development and implementation of effective control and prevention strategies.

Cryptosporidiosis is one of the leading causes of diarrhea in humans and several vertebrates 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 state, 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 one marker. Sequencing of the 18S rRNA amplicons revealed the presence of Cryptosporidium parvum in two HIV positive patients and in a child; the actin sequence confirmed the presence of this species. Two samples of HIV-positive patients amplified C. hominis 18S rRNA, one of them confirmed by the HSP-70, actin and gp60 sequences. C. meleagridis was found in another HIV patient, while C. hominis was detected in three children (of which two were confirmed by gp60). C. muris was found in one child. In birds, we found C. meleagridis and, significantly, C. parvum, whereas we detected C. parvum and C. muris in one goat each. The only dog sampled was positive for Cryptosporidium canis. We conclude that, in the environment we surveyed, humans and animals are potential part of the same transmission cycle. Measures to prevent zoonotic transmission should therefore be considered to reduce the prevalence of cryptosporidiosis.