New strain of Foot and Mouth Disease threatens Near East and Europe
A new strain of Foot and Mouth Disease (FMD) - a disease that affects cattle and other livestock - appears to have spread from Iran into Turkey, according to the FAO World Reference Laboratory (WRL) for Foot and Mouth Disease (FMD) at Pirbright, UK. The WRL has issued a warning "that current vaccines are not likely to protect against challenge by the variant". This leaves cattle across the Near East and southeast Europe vulnerable to the disease.
There are seven types of the virus that causes FMD, which are then divided into sub-types and strains.The newly discovered variant strain is of Type A and shows significant genetic differences from all other strains of the same type. It was first identified in Iran, in 1996. Samples collected in Turkey in 1997 and 1998 - where vaccinated animals were falling sick - have now been found to be the same new variant.
In the FMD warning, the Director of the WRL, Alex Donaldson said, "It can be concluded that the Type A variant, first identified in Iran, has extended its geographical distribution into Asiatic Turkey and is now a threat to other countries in Asia and to Europe, especially those countries which are linked to Iran and Turkey by trade in livestock."
In the early 1950s, a major FMD epidemic in Europe and the Near East - caused by the emergence of a new strain of Type A FMD (identified as sub-type A5) - resulted in 870,000 outbreaks and losses estimated at US$600 million. A similar episode occurred in the 1960s. In autumn 1964, a new variant of the Type A virus - later classified as A22 - appeared in Iran. The A22 epidemic swept through most of the Near East from Afghanistan to Turkey and by mid-1965 it had reached Thrace. FAO's Senior Officer for EMPRES (Emergency Prevention System) and Infectious Diseases, Mark Rweyemamu, said, "We are worried that what happened in the 1960s could recur" unless immediate steps are taken to contain the new variant.
Much depends on quick response to the new virus strain. "In terms of technology, we should be able to avoid such a catastrophe," Rweyemamu said. "We have the tools. The system for quick response and containment is much improved, provided those concerned are sufficiently alerted." Rweyemamu called for action in two areas:
FMD is a highly contagious disease of cloven-hoofed animals such as buffalo, oxen, sheep and goats. Except in very young animals, FMD mortality rates are low compared to those caused by diseases such as rinderpest. But FMD causes heavy losses in milk and meat production, as well as loss of draught power. It can also cause major disruption and reductions in international trade of livestock products.
Yves Leforban, the Secretary of the European Commission for the Control of FMD (EUFMD) stated that Europe has been free of the disease for almost two years. The last European episode caused by an A22-like virus occurred in Albania, the Former Yugoslav Republic of Macedonia and the Federal Republic of Yugoslavia in May 1996. The outbreak was rapidly controlled by a combination of the destruction of infected animals and vaccination of susceptible livestock in areas surrounding the infected zones in Albania and in Macedonia FYR.
Because the vaccines currently available in vaccine/antigen banks of Europe are likely to be ineffective against the new Type A variant strain, FAO and EUFMD are urging close collaboration between the veterinary services of Member Countries in Europe and the Near East, manufacturers of vaccines and international organizations in order to accelerate the development of a new vaccine and to enhance national vigilance against FMD. Development of a new vaccine will take a minimum of two months.
8 April 1998