February 21, 2007

 

Swine circovirus vaccines work, but supplies are scarce

 

 

Vaccines for the deadly hog circovirus are working satisfactorily when used properly, but supplies are falling short of producers' needs, according to industry sources and veterinarians in the US.

 

Porcine circovirus associated disease (PCVAD) is endemic in every swine herd in North America and other hog-producing nations, according to animal health experts. Among its symptoms are anorexia, rapid weight loss, unthrifty pigs, respiratory problems and diarrhoea. Hog deaths from the virus can drive up producer costs, though it is hard at this point to determine the extent of losses.

 

The disease, first identified in Canada in the 1990s, spread to Europe then to the US. More cases have been found in Canada and the US since 2004.

 

Circovirus vaccines became available commercially early last year and have become widely sought. The demand has left scarce supplies, however.

 

Broader use of the vaccines has reportedly reduced the number of deaths significantly in some production units. However, a veteran livestock dealer in Iowa, who requested anonymity, said he knows of several producers who are on the backorder list for the vaccines.

 

Calls and e-mails to two of the three major manufacturers of circovirus vaccines were not immediately returned.

 

A spokesman for Fort Dodge Animal Health, a major manufacturer of health-care products for livestock and companion animals, said the scarcity of the vaccine is because of the "unexpected outbreaks and widespread nature of the disease". Fort Dodge provides the vaccine known as Suvaxyn PCV2 One Dose.

 

Kelly Goss, associate director of communications at Fort Dodge, said the production cycle for any product requires a certain amount of lead time.

 

"When demand exceeds normal production capacity, a shortage of product in the marketplace is experienced," she said.

 

Goss said "unforeseen challenges sometimes develop on a new product and that was the case with our circovirus vaccine."

 

The company has since addressed those challenges and has resumed supplying product to the market, she said. It is moving to enhance its production capabilities to develop more vaccine, she added.

 

It has been difficult to obtain solid data on the number of animals killed by the disease because producers aren't required to report cases of circovirus disease to animal health officials. There have been reports, however, of losses as high as 35-40 percent in some production units.

 

Meanwhile, utilising bio-security measures and best management practices has reduced losses overall by controlling other diseases and stress factors that can increase the severity of PCVAD, but it can still strike even the best managed facilities and cause significant losses.

 

John Johnson, serology section leader at Iowa State University's veterinary diagnostic laboratory, told Dow Jones Newswires that when used properly, the vaccines for circovirus disease have been found to be very effective, according to feedback he has received from swine veterinarians and producers.

 

Johnson said the timing of vaccinations is important, with the best results seen when pigs are treated at a young age. He also said because the virus is endemic, it is essentially impossible to find swine that test negative for the virus.