The animal behind the scare that nearly paralysed the beef sector
Following reports of buffaloes in the Southern District early in April, the fear of the dreaded Foot and Mouth Disease (FMD) had once again reared its ugly head this time in Zone 11 (Southern, Kgatleng, South East and Kweneng Districts) thereby paralyzing the beef trade.
The buffalo and the FMD scare have led to the Department of Veterinary Services (DVS) issuing a ban (which has since been lifted) on the movement of all cloven hooved animals into, out of and within Zone 11. The ban had also led to the suspension of all beef exports by the Botswana Meat Commission (BMC). This move affected not only the famers, retailers and consumers within the zone but sent negative economic ripples across the country one way or the other.
But what is it about the buffalo and FMD that could cause such a nationwide pandemonium?
The African buffaloes are known as important natural reservoirs of the FMD infection also known as a “maintenance host,” meaning that they maintain a reservoir of the virus that can re-infect domesticated animals.
Researchers state that that the common ancestor of all South African Type of FMD (SAT 2) was in the African buffalo and the disease has over time been transferred from buffalo to cattle.
According to a scientific research paper by G. R. Thompson, W. Vosloo, J.J. Esterhuysen and R.G. Bengis there is circumstantial evidence that indicates that buffalo populations in Southern Africa are the major source of FMD.
“However, precisely how transmission from buffalo to cattle usually occurs is a matter of contention which is unlikely to be resolved until a clearer understanding is obtained of how FMD viruses are maintained in buffalo populations,” says the research paper.
“Buffalo acutely-infected with the SAT types of FMD virus excrete the virus by the same routes and in approximately the same quantities as acutely-infected cattle but, unlike cattle, most naturally-infected buffalo do not develop obvious signs of FMD.”
According to Bengis’ findings because buffalo are herd animals and usually experience infection early in life, it has been postulated that SAT type viruses are maintained in buffalo populations as “childhood” infections. However, during such “epidemics”, breeding herds of buffalo would be likely to provide a potent source of infectivity for other wild or domestic species in the immediate vicinity.
Following the acute phase of infection (less than 2 weeks), a high proportion of buffalo maintain the virus for periods of five years and probably longer, thereby becoming so-called “carriers.” However, carriers are inefficient transmitters of the infection to cattle in close proximity. FMB