Rabies 2007: perspective from Asia.

Rabies remains a public health problem in many parts of the less developed world. Much is known about the virology, pathophysiology, epidemiology, and methods for control but this knowledge is not applied in many countries. Thailand has been on the frontline of efforts to conduct research in rabies for almost a century, starting with Dr. Leopold Robert from the Institute Pasteur of Paris. He was invited by the Thai King in 1913 to develop a research and production facility for rabies vaccine and snake antivenins which later became the Queen Saovabha Memorial Institute. Thai physicians, scientists and nurses, jointly with some notable expatriate colleagues, were then responsible for major advances in rabies vaccine development, rational application of preand postexposure prophylaxis and better understanding of immunology and pathophysiology of this dread disease. They not only discovered new scientific principles but also cost-benefit methods for their application and set the foundation for the work conducted in Thailand during the next two decades. Many concepts developed by Thai scientists have been incorporated into WHO and US-CDC rabies management guidelines. This is an overview of significant developments during the past two decades [1-8].

Intratesticular injection of a balanced zinc solution for permanent sterilization of dogs.

Five male mature dogs with normal sex organs and normal pre-study semen evaluation received intratesticular injections of a sterile solution of balanced zinc gluconate. Semen without sperm could be collected on days 26, 30, 35 and 51 from 4 dogs. The dogs achieved penile erection but no ejaculation before these days. There were no significant adverse effects and no change in the dog behavior during the time that they were observed. Histopathological findings documented virtually complete fibrosis of seminiferous tubules and Leydig cells on days 60 and 75. This preliminary study concludes that balanced zinc gluconate may be used to sterilize dogs.

Risk of rabies after mammal bites in Thai children.

The data were collected by questionnaire at the Outpatient Department of Chulalongkorn University Hospital, Bangkok Thailand. This study revealed that 52 per cent of children had pet mammals in their home of which 67 per cent were dogs. 23.6 per cent of these children gave at least one history of a mammal bite inside (53.4%) or outside (46.6%) their house. Mammal bites of children could be found at all ages. However, most were in the age group of 10-14 years (42.3%), and 5-9 years (39.7%). The most common site of injury was on the legs (56.6%) and hands (30.7%). 31.7 per cent and 68.3 per cent of the bitten children incurred WHO category II and III potential rabies exposures (moderate and severe). 61.9 per cent had performed wound cleansing on each bite injury site and 34 per cent did not. 72 per cent of the children who had mammal bites received no post-exposure rabies treatment and 85.7 per cent did not make any effort to capture or observe the animal who had bitten them. Only 10.6 per cent observed the animals for 10 days or more. It was concluded that children are at considerable risk of mammal bites and that they are not receiving optimal care in this canine rabies endemic region and that 50 per cent of human rabies cases in Thailand were in children under 15 years of age.

Dog rabies in Bangkok.

Canine rabies remains a serious public health problem in Thailand. The Queen Saovabha Memorial Institute (QSMI) of the Thai Red Cross Society is the principal rabies diagnostic center in central Thailand. The retrospective study of canine rabies cases collected between 1994-1999 revealed that: (1) The prevalence of rabid dogs has decreased, and was associated with an overall decrease in the number of animals submitted for examination. However, the percentages of dogs with positive Fluorescent antibody test (FA) remained the same at approximately 40 per cent. (2) About 62 per cent of rabid dogs were less than one year old. Dogs at this age are more active and most have not been adequately vaccinated. Approximately 80 per cent of rabid dogs had never been vaccinated against rabies.