Posted on July 18, 2012
A foot-and-mouth disease vaccine developed by federal researchers can be manufactured in the U.S. and could be administered if an outbreak were to occur.
The adenovirus vaccine, which the Department of Agriculture conditionally approved in June, can be manufactured on the U.S. mainland because it does not contain live virus.
Marvin J. Grubman, PhD, a supervisory research chemist for the USDA Agricultural Research Service, has led since the late 1990s the research effort that created the vaccine at the Plum Island Animal Disease Center, which is located off the tip of New York’s Long Island. He and other researchers are now working to increase the potency of the vaccine in hopes of decreasing its cost to at least that for inactivated-virus vaccines.
Dr. Luis L. Rodriguez, the ARS research leader at Plum Island, said the vaccine has induced immunity in cattle and pigs within seven days.
“So, that early response, it is very important for an outbreak control situation where you need to protect the animals as soon as possible to avoid the spread of the virus throughout the country,” Dr. Rodriguez said.
The Department of Homeland Security, with ARS and industry collaboration, further developed the vaccine and conducted research needed to gain the conditional license.
“There are huge challenges that are remaining on foot-and-mouth disease vaccines, and both Dr. Grubman and others in our research unit are working hard—in collaboration with multiple partners around the world—to try to come up with better vaccines.”
Dr. Luis L. Rodriguez, USDA Agricultural Research Service research leader, Plum Island Animal Disease Center
Dr. Rodriguez said the vaccine can be manufactured safely without use of highly secure biological containment facilities. It also lacks the genes for several proteins that are present in the live virus, offering protection while inducing an identifiable difference in an animal’s immune response.
“That is a critical feature that would be very useful in a control situation where you are trying to deal with an outbreak of disease, and, in the process of recovery, you’re trying to remove the animals that have been infected and keep only those that have been vaccinated and noninfected,” he said.
The Center for Veterinary Biologics in the USDA Animal and Plant Health Inspection Service grants conditional licenses for biologics intended for use to “meet an emergency condition, limited market, local situation, or other special circumstance,” agency information states.
Dr. Rodriguez hopes the vaccine will become part of the National Veterinary Stockpile administered by APHIS.
“However, it is possible that, in the future, other countries around the world might also be interested in using this vaccine for emergency use,” he said.
APHIS spokeswoman Lyndsay M. Cole said the agency couldn’t speculate whether the vaccine would be added to the stockpile or used in response to an outbreak. But she said the agency knows the vaccine technology is available.
Other vaccines are stored as frozen antigen concentrates in the North American Foot and Mouth Disease Vaccine Bank administered by the U.S., Canada, and Mexico.
Dr. Rodriguez said global control and eradication of foot-and-mouth disease could require a vaccine with longer duration of immunity than the six months provided by inactivated-virus vaccines. The adenovirus vaccine has offered protection for at least 42 days, but the agency hasn’t tested beyond that point.
He also noted that there are seven FMD virus serotypes and additional subtypes, each requiring separate vaccines. He said much of the FMD vaccine research is focused on developing vaccines that induce broader immune responses that can protect against multiple serotypes.
“There are huge challenges that are remaining on foot-and-mouth disease vaccines, and both Dr. Grubman and others in our research unit are working hard—in collaboration with multiple partners around the world—to try to come up with better vaccines,” Dr. Rodriguez said.
Dr. Grubman indicated FMD vaccines, like human-use influenza vaccines, are tailored to protect against the virus serotypes and subtypes expected to pose the greatest risk of infection at the time the vaccines are produced.
Dr. Rodriguez said the veterinary research conducted to develop the vaccine could have a huge global impact.
“There are millions of people whose animals are of less value or produce less because of foot-and-mouth disease,” he said.