Current Scenario and Future Perspectives of CPV-2 Vaccines in India

Canine parvovirus causes acute hemorrhagic gastroenteritis in canines. It is prone to genetic evolution and has undergone several mutations that have led to various antigenic variants of CPV-2.Vaccination is the most cost-effective and ideal method to control the canine parvovirus infections. Both live attenuated and inactivated vaccines are available to control the disease in animals. Vaccines used during the late 1970s and early 1980s were of feline panleukopenia virus (FPV) origin, which was followed by the use of inactivated and live attenuated vaccines of CPV-2 canine origin. High-titer and low-passage CPV vaccines containing a canine-origin attenuated virus are currently considered vaccines-of-choice for use in pups of any breed. Vaccination is likely to be successful when the maternal antibody titer has declined to less than 1:10. Titers below 1:40 are variably protective, but they may interfere with vaccination. Strain difference between field virus and vaccine candidate virus could be one of the important attributable reasons for immunization failure in the country. The high rate of infection in both vaccinated and unvaccinated dogs raise questions on relevance of the present day vaccines, which in most countries contain old variants. Though some believe that the heterologous protection offered by these old strains against the new variants is good enough, a growing proportion think that the time has come to manufacture vaccines incorporating the variants prevalent in a country.