EPIDEMIOLOGICAL STUDIES OF CANINE RABIES
Canine rabies is endemic and occurs throughout the year in all parts of Nigeria. A descriptive cross sectional study was designed to assess knowledge, attitude and practice of dog owners towards rabies, to check for the presence of rabies antigens in brain tissue of dogs slaughtered for human consumption and to assess rabies vaccination coverage of dogs in Wukari. Structured questionnaires were prepared and administered to 200 dog owners by face to face interview. The questionnaire sought information on demographic characteristics of the dog owners, their association with dogs, knowledge, attitude and practice of dog owners towards rabies. Associations between demographic variables and knowledge, attitude or practice scores were assessed using χ2 analysis. Also, 188 brain samples from slaughtered dogs were analysed for presence of rabies antigen using direct fluorescent antibody test. Record files and vaccination certificates of dogs presented to the State Veterinary Hospital Wukari were assessed for anti-rabies vaccination coverage. Out of the 200 dog owners, only 26(13%) knew that rabies virus can be found in nervous tissue, 121 (60.5%) were aware that rabies can be spread through the saliva of a rabid animal, but majority of respondents 172(86%) did not know the age for first vaccination of dogs against rabies. Dog owners who were civil servants were 4.8 times more likely to have good knowledge (OR=4.84, 95% CI on OR 1.09-21.44) than those of other occupation groups. Positive attitude towards rabies increased with increase in age of dog owners, with respondents within the age group 20-30 years more likely to have negative attitude than those over 40 years. Civil servants were 9.8 times more likely to have good practice than other occupation groups. Rabies antigen was detected in 7.98% of slaughtered dogs. Out of 8,370 dogs presented to the State Veterinary Hospital Wukari, between January 2003 and December 2012, only 1,128(13.50%) received anti-rabies vaccine. The findings in this study showed inadequate knowledge, negative attitude and practice of dog owners towards rabies. The presence of rabies antigen in some dogs slaughtered for human consumption and low vaccination coverage in dogs indicate high risk of exposure of dog owners and dog meat processors to rabies. There is therefore a need for educational programmes targeted at dog owners to increase their level of knowledge and reduce the risk of exposure to rabies.
1.1 Background Information
Rabies is a viral zoonotic disease of all warm blooded animals, which is worldwide in distribution and causes acute encephalitis. It is also known as hydrophobia and is caused by a neutrophilic bullet-shaped, enveloped RNA virus, of the genus Lyssavirus and the family Rhabdoviridae. The disease is transmissible to all mammals (WHO 2006). Rabies originated about 3000BC and is one of the most typical zoonoses that have been well known since ancient times (Takayama, 2005). The disease is endemic in developing countries including Nigeria and other parts of sub-Saharan Africa and Asia (Harry et al., 1984; WHO, 2005). It is characterized by acute progressive encephalitis, hydrophobia, excitability and hypersalivation.
This disease occurs in more than 150 countries and territories and about 55, 000 people die of rabies every year, mostly in Africa, Asia, and South America (Beard, 2001; WHO, 2010). Forty percent of people who are bitten by suspected rabid animals are children under 15 years of age and dogs are the source of 99% of human rabies deaths (WHO, 2010). Every year, more than 15 million people worldwide receive a post-exposure preventive regimen to avert the disease – this is estimated to prevent 327 000 rabies deaths annually (WHO, 2010). Rabies was first reported in Nigeria in 1912 in humans (Boulger and Hardy, 1960) but the first laboratory confirmation was in 1925, by demonstration of Negri bodies in the brain smear of a mad dog (Ekele and Okoh, 1984). The disease has been declared endemic in Nigeria by several authors (Umoh and Belino, 1979; Fagbami et al., 1981).
The rabies virus causes acute encephalitis in all warm blooded mammals including man and the outcome is almost always fatal, with a variable incubation period (Nadin-Davies, 2000; Awoyomi et al., 2007; CDC, 2007; WHO, 2010). Although species of mammals are susceptible to rabies virus, only a few serve as reservoirs for the disease (Garba et al., 2009). In Nigeria, the domestic dog serves as the principal reservoir host and transmitter of rabies virus to animals and humans (Dzikwi et al., 2010; WHO, 2010).