Occurrence of Rabies Virus among Apparently Healthy Dogs and Bats Slaughtered for Meat in Some Selected Local Governments of Enugu State

Abstract

This work was undertaken to investigate whether or not rabies virus is present in the brains and saliva of apparently healthy dogs and bats slaughtered for human consumption in Enugu State, Southeastern Nigeria; attempt to establish possible exposure potential of humans to rabies virus through handling, processing, selling, buying, and consumption of dog meat and to establish the genotype of the viral isolates if any. A total of 100 questionnaires were distributed to those that sell dog or dog meat. One hundred and fifty two dog heads and fifty nine bat heads were collected from markets, restaurants and bars where these animals are slaughtered and consumed as delicacy in the study area and processed accordingly. The points of collection were georefrenced using global positioning system (GPS). Sex and age of dogs were noted at points of collection. Eighty seven percent of the dog meats sold were sourced from dogs bought from homes and markets while the rest (13%) were sourced from stray dogs. Eighty one percent of the respondents reported eating dog meat because it cures some diseases including reducing high blood pressure while the rest (19%) perceive it just as any other meat. Specifically, 50% was of the opinion that the meat of rabid dog enhances male libido. Twelve percent of respondents had been bitten by suspected rabid dog in the course of the business yet only one person (2%) indicated that he received full course of anti-rabies vaccination in a hospital. Seventy one percent of the respondents had slaughtered and eaten suspected rabid dogs. Out of the 152 dog brain samples examined, 18 (12%) were positive for rabies virus antigen using FAT while 17 (11%) were positive using MIT. Nine (17.6%) out of 51 male and nine (8.9%) out of the 101 female dog heads examined were positive for rabies virus antigen. seventeen (13%) of the 131 adult dog brains tested positive for rabies virus antigen, while 1(5%) of the puppy brains tested positive. There was no significant association (p > 0.05) between gender or age and the occurrence of rabies virus antigen in the brain of dogs. There was no significant association (p > 0.05) between occurrence of rabies virus antigen and senatorial zones. Out of a total of 10 salivary glands from positive brains that were analyzed by FAT, all (100%) tested positive for rabies virus antigen. All the 59 (100%) bat brain samples tested were negative for rabies virus antigen using FAT. All the rabies virus isolates from dog brain samples belonged to genotype 1 rabies virus (true rabies virus). The geographic information system (GIS) revealed that the positive dog brain samples were collected from 5 out of the 6 local government areas (LGAs) sampled and from 7 locations within the 5 LGAs; Udenu (1 location), Enugu North (1), Nsukka (2), Igbo-Etiti (2), and Udi (1). This study has shown that some of the apparently healthy dogs slaughtered for meat in Enugu state carry rabies virus and secrete the virus in their saliva without showing clinical signs. All the isolates belonged to genotype 1 rabies virus. No rabies virus antigen was found among apparently healthy bats slaughtered for meat in Enugu state. Furthermore, this work has revealed that those involved in dog trade or butchering have high exposure potential to rabies virus antigen