Rabies is a disease endemic to many parts of Southeast Asia (except Singapore), the Philippines, Africa, the Indian Subcontinent and tropical South America. With increasing numbers of travelers to these regions, exposure to rabies is becoming a greater health risk.

What is Rabies?

Rabies is a disease of the nervous system caused by the deadly rhabdovirus. It is transmitted by the infected saliva of animals. Infected (or rabid) animals are of two groups : urban or domestic animals such as dogs and cats (not vaccinated) and the sylvatic or wild animals such as skunks, foxes, raccoons, mongooses, wolves , bats and monkeys. In most areas of the world, dogs are the principle source of human infection.

What are the Symptoms of Rabies?

After a bite by an infected animal, the incubation period of rabies ranges from 10 days to over one year (the average time being one to two months). To a large extent, the incubation period depends on the amount of virus introduced and the location of the bite.

The first symptoms are non-specific, and consist of fever, headaches, lethargy, muscle aches, nausea, vomiting, sore throat or mild cough. These symptoms last from one to four days.

Subsequently, the patient develops confusion, excitability, agitation and abnormalities of the autonomic nervous system including dilated pupils, excessive sweating, salivation, swallowing difficulties and low blood pressure. Ultimately, the patient lapses into a coma and dies of respiratory arrest.

How can Rabies be Prevented?

Once the symptoms of rabies begin, there is no effective treatment and death usually occurs within several days. Fortunately, the disease can be prevented by early wound treatment and administration of vaccines.

All animal wounds should be immediately scrubbed with soap and then flushed with water. A tetanus toxoid injection and antibiotics should also be given. Infected wounds, and wounds older than 24 hours should not be sutured or closed; closure of other wounds is controversial. If a wild or stray domestic animal bites a person (especially if the animal is unprovoked or exhibits unusual behavior), the animal should be captured and destroyed. Its brain should then be sent for laboratory analysis. If rabies is confirmed or the animal cannot be captured, then immunization needs to be given.

Immunization consists of intramuscular injections of both rabies immune globulin (for immediate, but short lasting protection against rabies) and rabies vaccine (for development of lasting protection).

If bitten by a "healthy" dog or cat in an area endemic for rabies, the animal should be captured and closely observed for 10 days. If the animal remains healthy during this period, no treatment is necessary. If the animal is rabid or suspected to be rabid, then vaccination should be administered.

For those individuals who have greater exposure to rabies, such as veterinarians, cave explorers, animal handlers or workers in endemic areas, pre-exposure vaccination is recommended to strengthen their immunity against this virus. Questions concerning this article may be directed to The Singapore American, or contact 6738-0526.