States, South Africa Cooperating on FMD Vaccines
By David Elstein
March 12, 2002
Scientists with the
Agricultural Research Service and the
Veterinary Institute in South Africa have undertaken a two-year cooperative
study to produce new vaccines for foot-and-mouth disease (FMD).
FMD is a highly contagious disease of cloven-hoofed animals such as cattle,
pigs and sheep. Humans cannot get the disease but can act as mechanical
carriers for the virus that causes the disease. FMD usually doesnt kill
the animals, but does debilitate them, according to Peter Mason, leader of the
foot-and-mouth research at ARSs Plum Island Animal Disease Center,
Plum Island, N.Y. An infected animal develops virus-filled blisters around its
mouth, making eating difficult and the animal less productive. Infections near
the hooves make it difficult for the animal to walk. In addition, teats of
dairy animals are affected, hindering milk production.
Constant mutation by the FMD virus makes it hard for a vaccine to stay
effective. The cooperating scientists are using genetic engineering to develop
better vaccines that respond to changes in the virus.
A South African laboratory was chosen because of its international status
and its work on a number of FMD strains indigenous to Africa. Another reason
for partnering with an international laboratory is that U.S. companies cannot
produce vaccines from killed FMD virus on the U.S. mainland. The Plum Island
center is the only place in the United States where FMD can be studied.
According to Mason, it is important to work with other countries to find
vaccines for FMD even though the disease has not appeared in the United States
in more than 70 years. Limiting the presence of FMD overseas helps protect the
livestock of the United States, Mason notes. Scientists on Plum Island have
also worked with researchers from Brazil, China and Russia, but the partnership
with South Africa has advanced the farthest.
The cooperative agreement with South Africa lasts through May 30, 2003.
ARS is the U.S. Department of
Agricultures chief scientific research agency.