Molecular Detection of Rabies Lyssaviruses from Dogs in Southeastern Nigeria: Evidence of TransboundaryTransmission of Rabies in West Africa.

Despite being the first country to register confirmed cases of Mokola and Lagos bat lyssaviruses (two very distant lyssaviruses), knowledge gaps, particularly on the molecular epidemiology of lyssaviruses, still exist in Nigeria. A total of 278 specimens were collected from dogs in southeastern Nigeria between October 2015 and July 2016, and 23 (8.3%) of these tested positive for lyssaviruses with the direct fluorescent antibody test (DFA). The lyssaviruses were genetically characterized by amplifying the highly conserved nucleoprotein (N) gene of the rabies lyssaviruses (RABVs) of the viral genome. Phylogenetic analyses of the nucleotide sequences showed that all the RABV sequences in this study were of the Africa-2 lineage. Our results demonstrated that transboundary transmission of rabies lyssavirus is a key event, given that one of the RABV sequences (MN196576) clustered with rabies variants from neighboring Niger Republic. Furthermore, three RABVs from dogs from Anambra State clustered separately forming a novel and distinct group. Our results demonstrated that transboundary transmission of RABLVs is a key driver in the spread of rabies in West Africa. In order for the successful control of this zoonotic disease, a multinational stepwise surveillance and elimination of rabies in Africa by 2030 is probably the solution for regional elimination.

Prevalence and risk factors associated with Cryptosporidium spp. infection in local breed of dogs in Enugu State, Nigeria.

AIMS: Cryptosporidiosis is an important zoonotic disease of major public and veterinary concern. The disease affects humans and a variety of animal species including the domestic dog. This study aimed to determine the prevalence and risk factors associated with Cryptosporidium spp. infection in local breed of dogs from different homes and those presented at veterinary hospitals and clinics in Enugu State, Nigeria. MATERIALS AND METHODS: A total of 203 fresh fecal samples were collected from domestic dogs in six local government areas in Enugu State from February 2015 to August 2015. All the samples were examined using the formol-ether sedimentation method. Fecal smears were then stained by the modified Ziehl-Neelsen technique and examined under direct light microscopy. RESULTS: A total of 74 (36.5%) dogs were infected with Cryptosporidium spp. oocysts. There was a strong association (p<0.05) between the presence of Cryptosporidium spp. oocysts and management practices. However, there was no statistically significant association (p>0.05) between the presence of Cryptosporidium spp. oocysts and age, sex, and fecal consistency. CONCLUSION: The findings of this work suggest that domestic dogs in Enugu State harbor and shed Cryptosporidium spp. oocysts in the environment, especially those managed semi-intensively. Such fecal shedding is particularly so and of greater zoonotic and epidemiological importance in animals that do not show clinical signs and therefore not treated. They, therefore, pose a greater public health risk, especially to immune-compromised humans and animals. Public education on the zoonotic implication of this protozoan infection is of paramount importance in Enugu State, in particular, and Nigeria, in general, considering the closeness of dogs and man.

Detection of lyssavirus antigen and antibody levels among apparently healthy and suspected rabid dogs in South-Eastern Nigeria.

OBJECTIVES: Domestic dogs are the main reservoir of rabies virus (RABV) infection in Nigeria, thus surveillance of rabies in dog populations is crucial in order to understand the patterns of spread of infection and ultimately devise an appropriate rabies control strategy. This study determined the presence of lyssavirus antigen in brain tissues and anti-rabies antibodies in sera of apparently healthy and suspected-rabid dogs slaughtered for human consumption at local markets in South-Eastern Nigeria. RESULTS: Our findings demonstrated that 8.3% (n = 23) of brain tissues were lyssavirus positive and 2.5% (n = 25) of sera had rabies antibody levels as percentage blocking of 70% and above correlating with a cut-off value ≥ 0.5 IU/mL in the fluorescent antibody neutralization test. There was an inverse correlation between lyssavirus positivity and rabies antibody levels confirming that infected individuals most often do not develop virus neutralizing antibodies to the disease. The low percentage of rabies antibodies in this dog population suggests a susceptible population at high risk to RABV infection. These findings highlight a huge challenge to national rabies programs and subsequent elimination of the disease from Nigeria, considering that majority of dogs are confined to rural communal areas, where parenteral dog vaccination is not routinely undertaken.