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Also known as: '''''FMDV —  FMD'''''

Also known as: '''''FMDV —  FMD'''''

== Introduction ==

== Introduction ==

This [[:Category:Apthoviruses|Apthovirus]] is very small (25nm) +ss RNA virus, unenveloped and has a number a serotypes, namely '''Oise (O), ''''''Allemagne (A), ''''''C (also German), '''South African Territories (SAT) 1, 2, and 3 and India (Asia-1). Each serotype has '''at lease three subtypes. '''Serotype and subtype can be quickly identified by [[ELISA testing|'''ELISA''']] using guinea pig antisera. '''All isolates are virulent'''.

This [[:Category:Apthoviruses|Apthovirus]] is a small (25nm) +ss RNA virus, unenveloped and has 7 serotypes, namely '''Oise (O), ''''''Allemagne (A), ''''''C (also German), '''South African Territories (SAT) 1, 2, and 3 and Asia-1.  

This disease affects all '''cloven-hoofed animals, '''namely cattle, sheep, goats, pigs, deer, elephants and other wild ruminants such as buffalo and kudu etc. It does NOT afferct the horse. The main presentation of the disease is the formation of '''vesicles'''.

This disease affects all '''cloven-hoofed animals, '''namely cattle, sheep, goats, pigs, deer, elephants and other wild ruminants such as buffalo and kudu etc. It does NOT affect the horse. The main presentation of the disease is the formation of '''vesicles'''.

The disease is NOTIFIABLE in the UK and any animals with the disease, or in contact with the disease have to be destroyed.

The disease is NOTIFIABLE in the UK and any animals with the disease, or in contact with the disease have to be destroyed.

The virus replicates primarily in the upper respiratory tract, tonsils, or upper alimentary tract and there is '''aerosol''' excretion during this incubation period. This is then followed by a viremia. Virus targets stratum spinosum of stratified squamous epithelia and mucus membranes and secondary '''vesicles''' appear after incubation of 2-14 days. Lesions also affect the feet with cutaneous erosions in interdigital cleft, at coronet and bulbs of heals . These feet lesions often take a long time to heal as secondary bacterial infections may ensue and produce true deep ulcerative dermatitis. In the young, without maternal antibody, virus will localize in the heart and cause death by myocarditis. Persistent infection of cattle can occur in unkeratinized lesions, but subclinical carriers do not usually transfer infection except for subclinical buffalo that can transmit the disease.

The virus replicates primarily in the upper respiratory tract, tonsils, or upper alimentary tract and there is '''aerosol''' excretion during this incubation period. This is then followed by a viremia. Virus targets stratum spinosum of stratified squamous epithelia and mucus membranes and secondary '''vesicles''' appear after incubation of 2-14 days. Lesions also affect the feet with cutaneous erosions in interdigital cleft, at coronet and bulbs of heals . These feet lesions often take a long time to heal as secondary bacterial infections may ensue and produce true deep ulcerative dermatitis. In the young, without maternal antibody, virus will localize in the heart, particularly the wall of the left ventricle, resulting in multi-focal necrosis of the myocardium and subsequent death. Persistent infection of cattle can occur in unkeratinized lesions, but subclinical carriers do not usually transfer infection except for subclinical buffalo that can transmit the disease.

FMDV causes loss of condition and productivity but is NOT typically fatal. Aproximately 5% mortality (usually young animals); older animals recover. The virus is highly contagious and spread is by aerosol, direct contact, saliva, infected swill and fomites. Pigs produce 3000 times more aerosol virus than cows, but cows are much more susceptible to infection than pigs.

FMDV causes loss of condition and productivity but is NOT typically fatal. Approximately 5% mortality (usually young animals); older animals recover. The virus is highly contagious and spread is by aerosol, direct contact, saliva, infected swill and fomites. Pigs produce 3000 times more aerosol virus than cows, but cows are much more susceptible to infection than pigs.

In 1967 and 2001 there were major outbreaks in the UK. The disease is still widespread in many parts of world especially S. America and far East.

In 1967 and 2001 there were major outbreaks in the UK. The disease is still widespread in many parts of world especially S. America and far East.

== Control ==

== Control ==

Recovered animals show immunity ONLY to the subtype of first exposure, and even this is relatively short-lived, therefore re-exposure to the original serotype after immunity has waned will still result in virus excretion, even without clinical symptoms. Infection by a second serotype will result in clinical disease. It is for these reasons, that '''vaccination is not practiced''' in the UK. Further, vaccination would mean a loss of meat export markets.

Recovered animals show immunity ONLY to the serotype of first exposure, and even this is relatively short-lived, therefore re-exposure to the original serotype after immunity has waned will still result in virus excretion, even without clinical symptoms. Infection by a second serotype will result in clinical disease. It is for these reasons, that '''vaccination is not practiced''' in the UK. Further, vaccination would mean a loss of meat export markets.

===== Prevention in the UK =====

===== Prevention in the UK =====

'''In Endemic Areas''' disease cannot be prevented by slaughter due to large numbers of carrier stock. Annual '''inactivated whole virus vaccination''' using local subtypes is used. This vaccine is inactivated by azuridines, using alhydrogel adjuvant for cows, and oil for pigs. Subunit vaccines are ineffective. The course involves 2 initial injections at 4 months (if dams are vaccinated), followed by boosters every 6-12 months, which induces virus-neutralizing antibodies. Vaccination DOES NOT render meat harmful to consumers, but does affect when it can be exported.

'''In Endemic Areas''' disease cannot be prevented by slaughter due to large numbers of carrier stock. Annual '''inactivated whole virus vaccination''' using local subtypes is used. This vaccine is inactivated by azuridines, using alhydrogel adjuvant for cows, and oil for pigs. Subunit vaccines are ineffective. The course involves 2 initial injections at 4 months (if dams are vaccinated), followed by boosters every 6-12 months, which induces virus-neutralizing antibodies. Vaccination DOES NOT render meat harmful to consumers, but does affect when it can be exported.

== References ==

== References ==

[[Category:Apthoviruses]] [[Category:Oral_Diseases_-_Cattle]] [[Category:Oral_Diseases_-_Sheep]] [[Category:Oral_Diseases_-_Goat]] [[Category:Oral_Diseases_-_Pig]] [[Category:Dermatological_Diseases_-_Cattle]] [[Category:Dermatological_Diseases_-_Sheep]] [[Category:Dermatological_Diseases_-_Goat]] [[Category:Dermatological_Diseases_-_Pig]] [[Category:Oral_Cavity_-_Vesicular_Pathology]] [[Category:Integumentary_System_-_Viral_Infections]] [[Category:Viral_Myositis]]

[[Category:Apthoviruses]] [[Category:Oral_Diseases_-_Cattle]] [[Category:Oral_Diseases_-_Sheep]] [[Category:Oral_Diseases_-_Goat]] [[Category:Oral_Diseases_-_Pig]] [[Category:Dermatological_Diseases_-_Cattle]] [[Category:Dermatological_Diseases_-_Sheep]] [[Category:Dermatological_Diseases_-_Goat]] [[Category:Dermatological_Diseases_-_Pig]] [[Category:Oral_Cavity_-_Vesicular_Pathology]] [[Category:Integumentary_System_-_Viral_Infections]] [[Category:Viral_Myositis]]

[[Category:Expert Review - Farm Animal]]

[[Category:Expert Review - Farm Animal]]