24 May 2019

When to recommend a rabies vaccine

Clinical General practice Immunology

Given its high price tag of around $400, many patients planning short trips to countries where the rabies virus is common may baulk at getting the required three doses of vaccine prior to travelling.

While the risk of getting bitten or licked by a rabid animal is difficult to quantify, the consequences of not being pre-vaccinated can be considerable.

“The biggest question for travellers is whether to get the pre-exposure vaccination because everyone who’s had the pre-exposure vaccination will still need some booster vaccinations after an exposure,” says Dr Eddy Bajrovic, GP and medical director of Travelvax Australia.

But Dr Bajrovic says treatment for someone who is already vaccinated against rabies is “considerably easier” as only two vaccines are needed, starting as soon as possible after an exposure.

For patients who wish to be vaccinated against rabies, The Australian Immunisation Handbook recommends the pre-exposure vaccine is administered in three doses over three to four weeks for full coverage.

However, the WHO says two doses of the pre-exposure vaccine will offer an equally high level of protection.

Dr Bajrovic says while this advice remains off-label in Australia, it means GPs can still recommend the first two doses to a traveller who might be having their pre-travel consult only seven days before departure.

“I’m doing it. It’s worthwhile, especially for travellers going to parts of the world where access to RIG (rabies immunoglobulin) is scarce. You can get the two doses in seven days apart, and recommend they have the third dose when they return to Australia,” he says.

RIG is not required for those exposed travellers who have had a pre-exposure vaccination series.

A bite, scratch or lick on an open wound from an infected animal carries a risk of rabies and unvaccinated travellers when exposed, should seek the RIG and the required series of injections of vaccine as soon as possible.

RIG is not always readily available abroad meaning travellers are often forced to cut their trip short and return to Australia for the emergency treatment.

RIG is injected directly into the wound site followed by four post-exposure vaccines at day zero, three, seven and 14. Immunocompromised patients also receive a fifth dose.

Dr Bajrovic says RIG can be painful because it is administered directly into the wound site.

“It’s a significant amount of fluid into a wound which might be quite small, and the tissues are tight,” he says.

Rabies can only be prevented before the virus enters the nerves. Once this occurs and when symptoms appear, it’s is invariably incurable.

Exposure in an area of the body where there are lots of nerves, such as the hands or face also presents a heightened risk for travellers who may have less time before the virus enters their nervous system, so the need to seek post exposure vaccination is urgent.