Disease Control

Foot and mouth disease is a highly infectious viral disease of cloven-hoofed animals characterized by high fever followed by severe blisters inside the mouth and on the feet that restrict eating and movement.

While many animals eventually recover albeit with reduced health and productivity, death can be high in young animals. In addition, particularly aggressive strains of the virus can cause severe mortality. The sheer infectiousness of FMD can prompt drastic action – governments resorting to the mass slaughter of healthy animals to prevent the virus spreading. In Europe, the outbreak in 2001 resulted in the killing of millions of healthy animals with serious consequences for the farming sector and rural areas, many of which have still not truly recovered. Korea faced a similar situation in 2010 (see below). Overall, the Korean outbreak is estimated to have cost $3 billion.

Devastating effects in the developing world
FMD has largely been eliminated from developed countries and fortunately such outbreaks are rare. But the real damage occurs in poorer countries, those least able to bear its devastating costs. Across much of South and Central Asia, the Middle East and Africa, FMD remains endemic and hundreds of millions of dollars are lost annually due to restrictions on trade in animals and animal products, as well as vastly reduced domestic production of live animals, meat and dairy.

Tragically, the impact of FMD falls disproportionately on the very poorest populations. In countries where millions of families rely on perhaps just one or two animals for their survival, the impact of FMD can be life destroying. Farmers may have to stand by and watch their crops rot if the animals needed to reap the harvest and transport it to market have FMD. Growth and milk production from cows, pigs, sheep, goats, and other affected animals is drastically reduced and of poorer quality, and rarely regains previous levels. FMD thus keeps vulnerable communities rooted in poverty. Yet in the absence of FMD, livestock have many characteristics that make them important contributors to sustainable rural development and could allow rural households to participate in urban-based economic growth to a significant extent.

Challenges to eradication
The global control of FMD presents many challenges as the virus has evolved to survive. At the simplest level, there are 7 serotypes distributed around the world. Different serotypes affect different regions, and often more than one serotype is present. Within the serotypes, there are numerous topotypes and strains, which continually alter. With no cross-protection between serotypes, and limited cross-protection between topotypes, there is a constant demand for extensive field surveillance, advanced laboratory services to identify new circulating strains and technical know-how to identify and develop appropriate vaccines. Speed is obviously critical when it comes to dealing with outbreaks and at Merck Animal Health we work closely with reference laboratories to stay on top of the constantly evolving virus and identify strains and future threats. Vaccines have to be matched to a country's needs, sometimes requiring more than one serotype and including topotypes appropriate to the threat.

Korean outbreak 2010-211
In November 2010, the South Korean government reported a FMD outbreak leading to the culling of more than 3 million pigs, cattle, goats and deer. When initial measures proved ineffective, the Ministry for Food, Agriculture, Forestry and Fisheries took the decision to vaccinate all 13 million livestock in the country. Within weeks, Merck Animal Health was able to ship 12 million doses of vaccine demonstrating its capability to respond to a short-term demand in an emergency situation. In concert with other measures, within 5 weeks the large-scale vaccination campaign resulted in control of the outbreak.

Pan Asia vaccine development.
A new lineage to emerge has been the Pan Asia 2 variant of the O serotype and a new vaccine strain is needed to help countries counter the threat. MSD Animal Health has been the first major company to develop a new Pan Asia 2 strain to incorporate in a vaccine. It is already playing a pivotal role in efforts to control and eradicate the disease across Asia and the Middle East. Staying ahead of the game and being able to respond quickly, not just with strains but with effective high quality vaccines that provide high levels of protection, requires enormous investment and commitment.

Antigen banks
Even disease-free countries cannot afford to ignore the threat of FMD. Unprecedented globalization of trade and movement of people and animals opens the door for any virus strain to infect any part of the world. The maintenance of antigen banks for governments around the world can, under contract, guarantee rapid emergency supply of vaccines.

Through commercial supply, tenders and vaccine banks, Merck Animal Health works with governments and NGO's to develop new ways to control this important disease and move towards eventual global eradication ends.