Investigation of the antiviral effect of ribavirin and acyclovir on canine distemper and infectious canine hepatitis viruses

Abstract EN

Investigating the cytotoxic and antiviral effects of Ribavirin on Vero cells, it was found that ribavirin is a safe for Vero cells where neither growth inhibition nor cell toxicity have been recorded and a potent anti-canine distemper virus with all used concentrations (0.1, 1 ; 5 ; 10 ; 100and 200 µg / ml).

It was found that all vaccinated puppies with canine distemper vaccine did not show any abnormal clinical signs except 3 of them showed slight rise in rectal temperature (38.5-39oC) on the 2nd day post vaccination returned to its normal level (37-37.5 oC) by the treatment with a dose of 200µg of ribavirin injected intramuscularly for 3 successive days.

Also it was noticed that treatment of experimentally infected puppies with canine distemper revealed that the dose of 10µg / animal did not cure the disease completely where 2 puppies had progressed clinical signs of canine distemper like the untreated one while 100 and 200µg / animal resulted in complete curing of infected animals.

In addition, in vitro studies revealed that all tested concentrations of Acyclovir were found to be safe for Vero cell showing no cell toxicity and did not affect the cell growth kinetics.

On the other side it was noticed that complete antiviral effect of Acyclovir against CAV-1 was obtained by the use of concentrations of 200µg / ml / 100 TCID50 of the virus.

Vaccination of puppies with the live attenuated canine hepatitis vaccine resulted in rise in rectal temperature, diarrhea and corneal opacity in 2 puppies while the other 8 vaccinated puppies did not show any abnormal clinical signs.

So it could be concluded that ribavirin and acyclovir could be used as anti-canine distemper and anti-canine hepatitis respectively either in cases of post vaccination or post infection.