Todayโs path rounds are on ๐ฉ๐ฌ๐๐ฎ๐๐จ๐ซ๐๐๐ข๐๐ฌ!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ฌ๐๐ฎ๐๐จ๐ซ๐๐๐ข๐๐ฌ is a viral infection that mimics typical rabies, hence the name! However, this virus is actually a ๐ก๐๐ซ๐ฉ๐๐ฌ๐ฏ๐ข๐ซ๐ฎ๐ฌ, instead of a ๐ซ๐ก๐๐๐๐จ๐ฏ๐ข๐ซ๐ฎ๐ฌ like rabies.
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
Pigs are the ๐ง๐๐ญ๐ฎ๐ซ๐๐ฅ ๐ก๐จ๐ฌ๐ญ๐ฌ of this disease, meaning they are considered carriers of the virus. However, pseudorabies as a disease actually affects dogs, cats, cattle and small ruminants.
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
Pigs acquire this virus through contacting nasal secretions, saliva or urine of infected pigs. From there, the virus sets up shop in the tonsils, establishing a ๐ฅ๐๐ญ๐๐ง๐ญ ๐ข๐ง๐๐๐๐ญ๐ข๐จ๐ง. With this initial infection, pigs may show fever or mild ๐ง๐๐ฎ๐ซ๐จ๐ฅ๐จ๐ ๐ข๐ ๐ฌ๐ข๐ ๐ง๐ฌ like twitching or tremors, however they will usually recover quickly.
These latently infected pigs will continue to shed virus into the environment, potentially infecting other pigs or other species. In non-pig species, the virus enters the body and finds a local nerve ending to infect. From there, the virus migrates up the nerve ending to the spinal cord, causing widespread nervous system infection.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
When non-pig species are infected, the virus causes โ๐ฆ๐๐ ๐ข๐ญ๐๐กโ, where the animal becomes intensely itchy to the point where they appear frenzied or rabid. The virus may also cause drooling and loss of muscle tone in the jaw, which can look visually similar to rabies. Unfortunately, pseudorabies has a very high mortality rate in non-pig species, particularly in dogs.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
The best method of diagnosis is detecting the virus directly via ๐๐๐ or virus isolation conducted on nasal swabs of affected animals. At necropsy, their tissues can also be tested for the disease through similar methods.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐? ๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ฉ๐ซ๐๐ฏ๐๐ง๐ญ๐๐?
Unfortunately, there is no treatment for pseudorabies. However, strategic management and use of vaccines in pigs has allowed eradication of pseudorabies in commercial pig farms in the United States. The disease has not yet been reported in Canada thanks to our rigorous import regulations!
๐๐ก๐จ๐ญ๐จ๐ฌ
1-2) A poor dog with raw, damaged skin from itching and excessive drooling from pseudorabies.
3) A pig with excessive drooling from pseudorabies. Young pigs often develop similar clinical signs as non-pig species!
4-5) What pseudorabies looks like under the microscope! The classic findings are ๐ฉ๐๐ซ๐ข๐ฏ๐๐ฌ๐๐ฎ๐ฅ๐๐ซ ๐๐ฎ๐๐๐ข๐ง๐ of inflammatory cells around vessels, and ๐ข๐ง๐๐ฅ๐ฎ๐ฌ๐ข๐จ๐ง ๐๐จ๐๐ข๐๐ฌ within the nucleus of infected cells.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 1. Sixth Edition.
Dee SA. Pseudorabies in pigs. Merck Veterinary Manual 2021.
Photos 1-5 ยฉ Noahโs Arkive contributors Boosinger/Chang, Harrington, Park licensed under CC BY-SA 4.0.
