Emerging diseases: HP-PRRS

As part of Farmers Weekly’s round-up of emerging exotic diseases, Sarah Trickett speaks to Trevor Drew of the Veterinary Laboratories Agency about the rise of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome (HP-PRRS).

There is an increasing risk of arrival of HP-PRRS to the UK through illegal imports of pig products, including meat from Asia and particularly China where the disease is endemic, according to the VLA’s Trevor Drew.

“In the global market any virus emerging in the highly pathogenic form is a threat,” he says.

HP-PRRS has evolved from Type 2 PRRS and has spread through the Malaysian Peninsula to Southern Russia. “It has spread this far since 2007, although it is not in the EU yet,” says Prof Drew.

Symptoms are similar to classical swine fever, spreading rapidly through the pig population and often causing 100% mortality in youngstock. “The only distinguishable symptom from classical swine fever is pigs with HP-PRRS normally have severe respiratory problems,” he says.

There is no specific treatment for the highly pathogenic strain, although there is a vaccine for the Type 2 strain.

“This vaccine is not licensed for use in the UK partially because we don’t have Type 2 PRRS and also because the vaccine in some cases can spread Type 2 PRRS to non-vaccinated animals.”

However, Prof Drew stresses the disease can be controlled successfully by good biosecurity measures, disinfectant and surveillance. “This is not a hardy virus and it wouldn’t be difficult to disinfect against.”