Rat rabies in Phetchabun Province, Thailand.

The Queen Saovabha Memorial Institute in Bangkok sees approximately 7,000 human postexposure rabies patients yearly, of which approximately 1% are rat bites. In these exposures the rats could not be proven to be rabid because they could not be caught. This report documents a bite from a rat that was proven rabid. Mr. CC, a 45-year-old farmer in Phetchabun Province reported that he was attacked " fiercely " by a large rat (species not identified) while sleeping in his home and inside a mosquito net. He incurred multiple bites on his right hand and managed to capture and kill the rat. The rat was first examined by fluorescent antibody test (FAT) and mouse inoculation test (MIT) at the livestock department laboratory in Pitsanulok and in Phetchabun and the findings were later confirmed at the rabies reference laboratory (Queen Saovabha Memorial Institute, Thai Red Cross Society in Bangkok). Further studies using monoclonal antibodies, suggested that the rat had been infected with a common Asian dog rabies virus. The farmer received prompt postexposure prophylaxis against rabies including rabies immune globulin, injected into the bite sites, followed by a series of tissue culture vaccine. He remained well for the following year. Thailand is a canine rabies endemic country, which treats over 200,000 humans for rabies exposures annually. 1 There were 69 human rabies deaths in Thailand in the year 1999 and 51 in 2000; a dramatic decline since the early 1980s when up to 300 persons died of rabies every year. Wildlife rabies is not established in this region but there is thought to be bat rabies; however, little is known about this probable zoonosis. 2 There are at least 35 species of rats 3 in this region and these include the great bandicoot (Bandicota indica) weighing up to 545 grams but appearing to the layman to be very much like any other large rat. 3,4 Other common rats are Nor-way Rats (Rattus norveqicus, 300 g), Lesser White-toothed Rat (Rattus losea, 235 g), Ricefield Rat (Rattus argen-tiventer, 212 g), Island Rat (Rattus remotus, 221 g), and Lesser Bandicoot (Bandicota savilei, 199 g). Rabies in rats was first reported in Thailand by PC Smith in 1968 5 but experts have later shed doubt on this report (CE Rup-precht, personal communication, July 2001). The term " rat " is a generic one and is generally applied to any member of the mouse and rat families …