A rabies vaccine is a vaccine used to prevent rabies. There are a number of
available vaccines that are both safe and effective. They can be used to
prevent rabies before and for a period of time after exposure to the virus such
as by a dog or bat bite. The immunity that develops is long lasting after
three doses. They are usually given by injection into the skin or muscle. After
exposure vaccination is typically used along with rabies immunoglobulin. It is
recommended that those who are at high risk of exposure be vaccinated before
potential exposure. Vaccines are effective in humans and other animals.
Immunizing dogs is very effective in preventing human disease.
They may be safely used in all age groups. About 35 to 45 percent of people
develop a brief period of redness and pain at the injection site. About 5 to
15 percent of people may have fever, headaches or nausea. After exposure to
rabies there is no contraindication to its use. Most vaccines do not contain
thimerosal. Vaccines made from nerve tissue, and relied upon by a few
countries, mainly in Asia and Latin America, are less effective and have
greater side effects. Their use is thus not recommended by the World Health
Organization. Millions of people globally have been
vaccinated and it is estimated that this saves more than 250,000 people a year.
It is on the World Health Organization's List of Essential Medicines, the most
important medication recommended for a basic health system.
Modern vaccines The human diploid cell rabies vaccine
was started in 1967. Human diploid cell rabies vaccines are inactivated vaccines
made using the attenuated Pitman-Moore L503 strain of the virus. Human diploid
cell rabies vaccines have been given to more than 1.5 million people as of 2006.
Aside from vaccinating humans, another approach was also developed by
vaccinating dogs to prevent the spread of the virus. In 1979 the Van Houweling
Research Laboratory of the Silliman University Medical Center in Dumaguete
in the Philippines, then headed by Dr. George Beran, developed and produced a
dog vaccine that gave a three-year immunity from rabies. The development of
the vaccine resulted in the elimination of rabies in many parts of the Visayas
and Mindanao Islands. The successful program in the Philippines was later
used as a model by other countries, such as Ecuador and the Yucatan State of
Mexico, in their fight against rabies conducted in collaboration with the
World Health Organization. In addition to these developments, newer
and less expensive purified chicken embryo cell vaccine, and purified Vero
cell rabies vaccine are now available. The purified Vero cell rabies vaccine
uses the attenuated Wistar strain of the rabies virus, and uses the Vero cell
line as its host. In Tunisia a rabies control program was
initiated to give dog owners free vaccination to promote mass vaccination
which was sponsored by their government. The vaccine is known as Rabisin , which
is a cell based rabies vaccine only used countrywide. Vaccinations are often
administered when owners take in their dogs for check-ups and visits at the
vet. = Duration of immunity=
Immunity following a course of doses is typically long lasting. Following
administration of a booster dose, one study found 97% of immuno-competent
individuals demonstrate protective levels of neutralizing antibodies at 10
years. History
Virtually every infection with rabies resulted in death until two French
scientists, Louis Pasteur and Émile Roux, developed the first rabies
vaccination in 1885. This vaccine was first used on a human on July 6, 1885,
on nine-year-old Joseph Meister, who had been mauled by a rabid dog.
Their vaccine consisted of a sample of the virus harvested from infected
rabbits, which was weakened by allowing it to dry for 5 to 10 days. Similar
nerve tissue-derived vaccines are still used now in some countries, and while
they are much cheaper than modern cell culture vaccines, they are not as
effective. Neural tissue vaccines also carry a certain risk of neurological
complications. Other animals
Pre-exposure immunization has been used on domesticated and wild populations. In
many jurisdictions, domestic dogs, cats, ferrets, and rabbits are required to be
vaccinated. Imrab is an example of a veterinary
rabies vaccine containing the Pasteur strain of killed rabies virus. Several
different types of Imrab exist, including Imrab, Imrab 3, and Imrab
Large Animal. Imrab 3 has been approved for ferrets and, in some areas, pet
skunks. Oral vaccination against rabies is a
preventive measure to eradicate rabies in wild animals, vectors of disease,
mainly foxes, raccoons, raccoon dogs, coyotes and jackals, but also can be
used for dogs in developing countries. Baits are distributed by airplanes in
rural areas and by hand in urban and suburban areas. The idea of wildlife
vaccination was conceived during the 1960s, and modified-live rabies viruses
were used for the experimental oral vaccination of carnivores by the 1970s.
The development of safe and effective rabies virus vaccines applied in
attractive baits resulted in the first field trials in Switzerland in 1978.
= Recombinant rabies vaccine= In 1984 researchers at the Wistar
Institute developed a recombinant vaccine called V-RG by inserting the
glycoprotein gene from rabies into a vaccinia virus. The V-RG vaccine has
since been commercialised by Merial. It is harmless to humans and has been shown
to be safe for various species of animals that might accidentally
encounter it in the wild, including birds.
V-RG has been successfully used to prevent outbreaks of rabies in wildlife.
The vaccine is stable under relatively high temperatures and can be delivered
orally, making mass vaccination of wildlife possible by putting it in
baits. The plan for immunization of normal populations involves dropping
bait containing food wrapped around a small dose of the live virus. The bait
would be dropped by helicopter concentrating on areas that have not
been infected yet. In November 2008, Germany had been free of new cases for
two years and is therefore currently believed to be rabies-free, together
with a few other countries. A strategy of vaccinating “neighborhood dogs” in
Jaipur, India, combined with a sterilization program, has also resulted
in a large reduction in the number of human cases.
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