Background

In animals, Foot and Mouth disease (FMD) is a highly infectious viral disease particularly affecting cattle, sheep, pigs, goats, other farmed mammals and wild ruminants. FMD is one of the most important diseases of livestock, however there is no risk to human health.

On introduction to a herd or flock the infection can spread very rapidly by direct and indirect transmission. Affected animals have a high temperature, which is followed by the development of blisters chiefly in the mouth and on the feet. However, in some species (notably sheep and goats), the disease is frequently less severe or occurs as a sub-clinical infection. The disease is not usually fatal in adult animals, although many young animals may die. However, it causes severe pain and distress, especially in cattle; animals may be left permanently lame and the productivity of recovered animals may be reduced. Seven distinct serotypes of the virus have been identified. The clinical signs of FMD in animals are similar to several other vesicular diseases and confirmation of diagnosis can only be made following laboratory tests.

There was a large outbreak of FMD in the UK in 2001 in which 2,030 farms were affected. An incident occurred in 2007 when eight cases of FMD were confirmed in the south-east of England. Further information is available on the Defra website at http://archive.defra.gov.uk/foodfarm/farmanimal/diseases/atoz/fmd/2007/

Human infections

The virus only very rarely infects people and then produces a mild short- lived, self-limiting disease . There have been very few human cases even though the disease is endemic in many parts of the world including Asia, Africa, the Middle East and South America . The last human case in Britain occurred during the 1966 epidemic.

Transmission to humans

Foot and Mouth Disease virus is transmissible to humans, but it crosses the species barrier with great difficulty and with little effect. The method of transmission is uncertain, but only occurs through close contact with infected animals or specific exposure to the virus such as in the laboratory. All reported cases have had direct and close contact with infected animals or virus.

Workers handling infected animals or carcasses during the 2001 UK outbreak were monitored and no human cases of foot and mouth disease were confirmed.

There is no record of human-to-human spread.

The Food Standards Agency has advised that the disease has no implications for the human food chain and that there is no record of infection from pasteurized milk.

IIlness in humans

On the rare occasions when this occurs, it is a mild short- lived, self-limiting disease. The incubation period is 2-6 days. Symptoms are mild with blisters on the hands or other exposed areas, which may be accompanied by fever, headache, or sore throat. Patients recover within a few days.

This disease is not a public health threat from the perspective of infection, however the impact on livestock farming and other rural industries may lead to stress-related illness.

Confusingly, there is a human infection called Hand, Foot and Mouth disease , which is unrelated to Foot and Mouth Disease. This usually affects children and is caused by a different class of viruses (usually by Coxsackie A, a human enterovirus). It commonly causes a fever and generalised rash especially on the palms, fingers and soles of the feet. This disease does not affect animals.

Laboratory Diagnosis of suspected human cases

Samples from suspected human cases should be referred to:

Dr David Brown
Virus Reference Department
HPA Colindale

61 Colindale Ave
London NW9 5EQ
Telephone: 020 8327 6017  

More information on foot and mouth disease in animals including the current outbreak in Surrey and control measures is available on the Defra website: http://www.defra.gov.uk/animal-diseases/a-z/foot-and-mouth/

 

References

Armstrong R, Davie J, Hedger RS. Foot-and-mouth disease in man. BMJ 1967; 4: 529-530

Prempeh H, Smith R, Muller B. Foot and Mouth Disease: the human consequences.(editorial). BMJ 2001; 322: 565 Available on line at http://bmj.bmjjournals.com/cgi/content/full/322/7286/565

Bauer, K. Foot and Mouth Disease as a zoonosis. Arch Virol 1997; 13 (supp): 95-97.

Foot and Mouth Disease outbreak - no threat to public health. Commun Dis Rep CDR Weekly 2001:11 (1st March 2001) Available on line at http://www.hpa.org.uk/cdr/archives/2001/cdr0901.pdf