Serological and molecular surveillance for influenza A virus in dogs and their human contacts in Oyo State, Nigeria.

Evidence of influenza A virus (IAV) infection in dogs, a major companion animal of humans, suggests the possibility that they may constitute a new source for transmission of novel influenza viruses to humans. The potential public health risk posed by this possibility of interspecies spread of IAV between dogs and humans necessitated surveillance for the virus in dogs and their human contacts. Sera from 239 asymptomatic pet and hunting dogs in Oyo state, Nigeria were screened for anti-IAV nucleoprotein antibodies using competitive enzyme-linked immunosorbent assay (ELISA) while haemagglutination inhibiting (HI) antibodies in the positive sera were detected using influenza virus H3 and H5 subtypespecific antigens. Suspensions prepared from 239 and 39 nasal swabs from dogs and human contacts, respectively were tested for presence of the highly conserved IAV matrix gene by reverse transcriptase-polymerase chain reaction (RT-PCR). Only 4 (1.7%) of the 239 sera tested were positive by the ELISA. The HI test confirmed the presence of H3 influenza virus subtype-specific antibodies in one (25.0%) of the 4 ELISA-positive sera with a titre of 1:128 while none was positive for H5 subtype-specific antibodies. All the nasal swabs assayed by RT-PCR were negative for IAV nucleic acid. The detection of IAV antibodies in pet and hunting dogs in this study, although at a low rate, suggests that these dogs could play a crucial role in the zoonotic transmission of influenza viruses especially considering the close interaction between them and their human contacts. Continuous surveillance for IAV among dog populations in Oyo State (and Nigeria) is therefore advocated to facilitate early detection of infection or emergence of novel influenza virus strains that could be potentially harmful to humans and or animals.

Serological and molecular surveillance for influenza A virus in dogs and their human contacts in Oyo State, Nigeria

@#Evidence of influenza A virus (IAV) infection in dogs, a major companion animal of humans, suggests the possibility that they may constitute a new source for transmission of novel influenza viruses to humans. The potential public health risk posed by this possibility of interspecies spread of IAV between dogs and humans necessitated surveillance for the virus in dogs and their human contacts. Sera from 239 asymptomatic pet and hunting dogs in Oyo state, Nigeria were screened for anti-IAV nucleoprotein antibodies using competitive enzyme-linked immunosorbent assay (ELISA) while haemagglutination inhibiting (HI) antibodies in the positive sera were detected using influenza virus H3 and H5 subtypespecific antigens. Suspensions prepared from 239 and 39 nasal swabs from dogs and human contacts, respectively were tested for presence of the highly conserved IAV matrix gene by reverse transcriptase-polymerase chain reaction (RT-PCR). Only 4 (1.7%) of the 239 sera tested were positive by the ELISA. The HI test confirmed the presence of H3 influenza virus subtype-specific antibodies in one (25.0%) of the 4 ELISA-positive sera with a titre of 1:128 while none was positive for H5 subtype-specific antibodies. All the nasal swabs assayed by RT-PCR were negative for IAV nucleic acid. The detection of IAV antibodies in pet and hunting dogs in this study, although at a low rate, suggests that these dogs could play a crucial role in the zoonotic transmission of influenza viruses especially considering the close interaction between them and their human contacts. Continuous surveillance for IAV among dog populations in Oyo State (and Nigeria) is therefore advocated to facilitate early detection of infection or emergence of novel influenza virus strains that could be potentially harmful to humans and or animals.

Serological survey for emerging canine H3N8 and H3N2 influenza viruses in pet and village dogs in Nigeria.

BACKGROUND: In Nigeria, keeping of dogs as pets and guards is gaining popularity. To determine whether infection of dogs with novel canine influenza virus (CIV) of equine (H3N8) and avian (H3N2) origins had occurred in Nigeria, we screened pet and village dogs from Lagos, Ibadan, Odeda and Sagamu in southwestern Nigeria for antibodies to CIV H3N8 and H3N2. METHODS: Sera from 96 pet dogs presented at veterinary clinics in Lagos and Ibadan, and 89 village dogs from hunting communities in Odeda and Sagamu were tested for antibodies to CIV H3N8 and H3N2 using the hemagglutination inhibition test. RESULTS: Anti-CIV H3N8 antibodies were detected in 51 (53.1%) and 24 (27.0%) pet and village dogs, respectively. Overall, 40.5% (75/185) of the sera were positive for CIV H3N8 antibodies while none contained anti-CIV H3N2 antibodies. CONCLUSION: The presence of CIV H3N8 antibodies in pet and village dogs in this study suggests that they had natural exposure to the virus since dogs are not currently vaccinated against canine influenza in Nigeria. It is possible that the pet dogs acquired infection through contact with imported dogs in veterinary clinics, breeding kennels and dog shows while the village dogs could have been exposed through consumption of offal of infected animals killed during hunting. Considering the potential public health risk of this disease arising from the close relationship between pet and hunting dogs and their owners in Nigeria, systematic epidemiological surveillance of the Nigerian dog population for CIV H3N8, H3N2 and other influenza A virus subtypes is advocated.

Prevalence of Fasciola species in ruminants under extensive management system in Ibadan southwestern Nigeria.

BACKGROUND: Fasciolosis is a zoonotic trematode of ruminants and a common parasite in cattle in Nigeria. With the increasing numbers of small household cattle herds kept under extensive management system as well as the more usual small ruminants, there is a possibility therefore that parasites common to these ruminants but better adapted to cattle such as Fasciola may also be on the increase within the small ruminant population as they graze freely over the same wide area and sometimes freely mix. AIM: The aim of the study is to determine the prevalence of Fasciola spp in sheep, goats and cattle in Ibadan during the short wet season, (August-October 2011). METHODS: Faecal samples were collected per rectum from 440 each of goats and sheep and 291 cattle. Helminth ova were recovered using sedimentation technique for faecal examination. RESULTS: A total of 40 goats (9.1%), 53 sheep (12.0%) and 158 cattle (54.3%) were positive for Fasciola ova which reflects an increase in prevalence in small ruminants. CONCLUSION: This implies that the entire Ibadan is endemic for Fasciola spp and small ruminants may serve as an important link in the epidemiology of Fasciola spp infection. More so, this has implications for the scavenging household animals which receive little or no medical attention and man that may acquire this trematode by inadvertently eating vegetables with encysted Fasciola metacercariae.

Lack of protection against rabies in neighbourhood dogs in some peri-urban and rural areas of Ogun and Oyo states, Nigeria.

BACKGROUND: Rabies is a highly fatal zoonosis that causes severe destruction to the central nervous system and remains underreported in developing countries like Nigeria. OBJECTIVES: The increasing close contact between dogs and their owners or neighbours suggest a need for investigation of the protective level of rabies virus (RABV) antibodies in dogs. METHODS: Sera from 150 apparently healthy neighbourhood dogs from some peri-urban and rural areas of Ogun and Oyo states, southwestern Nigeria were analyzed for the presence of RABV antibodies using the indirect ELISA technique. These dogs were kept as pets, used for hunting or sold for human consumption. RESULTS: The results showed that none of the dogs had optimal RABV antibody titres, 25 (16.7%) had sub-optimal antibody titres while 125 (83.3%) were negative. Detection of sub-optimal RABV antibody levels in these unvaccinated dogs suggests that they might have been exposed to rabies or rabies-related viruses. Data obtained from interviews conducted revealed that 21.3% of the dog owners were informed about rabies but neglected vaccination while 44.7% were uninformed. CONCLUSIONS: We conclude that these dogs lacked protective levels of RABV antibodies and thus constitute a public, health threat. This finding underscores the need for dog anti-rabies vaccination campaigns covering peri-urban and rural areas as well as the promotion of large scale public enlightenment programmes on rabies in Nigeria.