User:Ryl3rs0n/Rabies vaccine

Article Draft: Contributions - Rabies vaccine
The rabies vaccine is a vaccine used to prevent rabies. There are several rabies vaccines available that are both safe and effective. Vaccinations must be administered prior to rabies virus exposure or within the latent period after exposure to prevent the disease. They can be used to prevent rabies before, and, for a period of time, after exposure to the rabies virus, which is commonly caused by a dog bite or a bat bite. '''Transmission of rabies virus to humans typically occurs through a bite or scratch from an infectious animal, but exposure can occur through indirect contact with the saliva from an infectious individual. '''

Doses are usually given by injection into the skin or muscle. After exposure, the 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. Rabies vaccines are effective in humans and other animals, and vaccinating dogs is very effective in preventing the spread of rabies to humans. A long-lasting immunity to the virus develops after a full course of treatment. Rabies vaccines may be used safely by all age groups. About 35 to 45 percent of people develop a brief period of redness and pain at the injection site, and 5 to 15 percent of people may experience fever, headaches, or nausea. After exposure to rabies, there is no contraindication to its use, because the untreated virus is virtually 100% fatal.

The first rabies vaccine was introduced in 1885 and was followed by an improved version in 1908. Millions of people globally are vaccinated against the virus. It is on the World Health Organization's List of Essential Medicines.

Wild animals
Wildlife species, primarily bats, raccoons, skunks, and foxes, act as reservoir species for different variants of the rabies virus in distinct geographic regions of the United States. This results in the general occurrence of rabies as well as outbreaks in animal populations. Approximately 90% of all reported rabies cases in the US are from wildlife.

Oral rabies vaccine
Oral rabies vaccines are distributed across the landscape, targeting reservoir species, in an effort in pellet form are intended to be given to wild animals to produce a herd immunity effect. 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. T he Development of an oral immunization for wildlife began in the United States development of safe and effective rabies virus vaccines with laboratory trials using the live, attenuated Evelyn-Rokitnicki-Abselseth (ERA) vaccine, derived from the Street Alabama Dufferin (SAD) strain. The first ORV field trial using the live attenuated vaccine to immunize foxes applied in attractive baits resulted in the first field trials and occured in Switzerland in during 1978 to immunize red foxes.

There are currently three different types of oral wildlife rabies vaccine in use:


 * Modified live virus: Attenuated vaccine strains of rabies virus such as SAG2 and SAD B19..
 * Recombinant vaccinia virus expressing rabies glycoprotein (V-RG): This is a strain of the vaccinia virus (originally a smallpox vaccine) that has been engineered to encode the gene for the rabies glycoprotein. It is mostly used in the USA (raccoons, foxes, and coyotes) and in western Europe (red foxes)
 * The V-RG oral vaccine does not contain the whole rabies virus and has been proven safe in over 60 animal species including cats and dogs. 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.
 * ONRAB: an experimental live recombinant adenovirus vaccine 

Oral rabies vaccination (ORV) programs have been used in many countries in an effort to control the spread of rabies and limit the risk of human contact with the rabies virus. ORV programs were initiated in Europe in the 1980s, Canada in 1985, and in the United States in 1990. ORV is a preventive measure to eliminate eradicate rabies in wild animal vectors of disease, mainly foxes, raccoons, raccoon dogs, coyotes and jackals, but also can be used for dogs in developing countries. ORV programs typically use edible attractive baits to deliver the vaccine to targeted animals. In the United States, RABORAL V-RG (Boehringer Ingelheim, Duluth, GA, USA) has been the only licensed ORV for rabies virus management since 1997. However, ONRAB "Ultralite" (Artemis Technologies Inc., Guelph, Ontario, Canada) baits have been distributed by the United States Department of Agriculture (USDA) in select areas of the eastern United States under an experimental permit to target raccoons since 2011.

RABORAL V-RG baits consist of a small packet containing the oral vaccine which is then either coated in a fishmeal paste or encased in a fishmeal-polymer block. ONRAB "Ultralite" baits consist of a blister pack with a coating matrix of vanilla flavor, green food coloring, vegetable oil and hydrogenated vegetable fat. When an animal bites into the bait, the packets burst and the vaccine is administered. Current research suggests that if adequate amounts of the vaccine is ingested, immunity to the virus should last for upwards of one year. By immunizing wild or stray animals, ORV programs work to create a buffer zone between the rabies virus and potential contact with humans, pets, or livestock. Landscape features such as large bodies of water and mountains are often used to enhance the effectiveness of the buffer. The effectiveness of ORV campaigns in specific areas is determined through trap-and-release methods. Titer tests are performed on the blood drawn from the sample animals in order to measure rabies antibody levels in the blood. Baits are usually distributed by aircraft to more efficiently cover large, rural regions. In order to place baits more precisely and to minimize human and pet contact with baits, however, they are distributed by hand in suburban or urban regions. The standard bait distribution density is 75 baits/km2 in rural areas and 150 baits/km2 in urban and developed areas.

Implementation of ORV programs in the United States has led seen to the elimination of the coyote rabies virus variant in 2003 and gray fox variant during 2013. Furthermore, ORV has been successful in preventing the westward spread of raccoon rabies variant and even eradicating rabies in red foxes in Switzerland.

The oral vaccine does not contain the whole rabies virus and has been proven safe in over 60 animal species including cats and dogs. 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 potential for human contact with baits is a present concern for ORV programs, but the inactivated rabies vaccine cannot cause rabies, and the recombinant poxvirus vaccine is based on an attenuated poxvirus which is unlikely to cause serious disease in humans anyway. In the USA between 1990 and 2000, over 22 million doses of vaccinia-rabies were distributed, but there were only 160 incidents of people touching a vaccine bait, and only one resulted in a serious infection. The person in this case had been bitten by her dog while removing a bait from its mouth.