Hand, foot and mouth disease

Notification requirement for hand, foot and mouth disease

Notification is not required.

Primary school and children’s services centre exclusion for hand, foot and mouth disease

Primary school and children’s services centres exclusion is required until all blisters have dried.

Infectious agent of hand, foot and mouth disease

The major agents causing hand, foot and mouth disease (HFMD) are the human enteroviruses species A, particularly coxsackievirus A16 (CA16) and enterovirus 71 (EV71). These belong to the genus Enterovirus within the family Picornaviridae.

Coxsackievirus A6 and coxsackievirus A10 are also associated with HFMD, and herpangina (acute febrile illness associated with small vesicular or ulcerative lesions on the posterior oropharyngeal structures).

Human hand, foot and mouth disease is unrelated to the foot-and-mouth disease of animals (caused by members of the genus Aphthovirus).

Identification of hand, foot and mouth disease

Clinical features

HFMD occurs mainly in children younger than 5 years of age. It can sometimes occur in adults. Symptoms and lesions usually persist for 7–10 days.

The clinical picture consists of fever, and vesicular lesions on the buccal surfaces of the cheeks, gums and sides of the tongue, beginning as small red spots that blister and often become ulcers.

Papulovesicular lesions of the palms, fingers and soles commonly occur over a 1–2-day period. Occasionally, maculopapular lesions appear on the knees, elbows, buttocks and genital area.

Some people, especially young children, may become dehydrated if they are not able to swallow enough liquids because of the painful mouth sores.

Complications include viral (aseptic) meningitis with headache, stiff neck and sensitivity to light, but this is rare.

Inflammation of the brain (encephalitis), paralysis or pulmonary oedema (fluid in the lungs) can occur, but are also very rare.

Fingernail and toenail loss have been reported, but this is only temporary, and nails grow back without medical treatment.

Diagnosis

Diagnosis of HFMD is usually clinical.

Depending on how severe the symptoms are, samples from throat, vesicle or stool are the most useful specimens for confirming the diagnosis of HFMD.

Polymerase chain reaction (PCR) can be used to confirm the diagnosis.

Incubation period of hand, foot and mouth disease viruses

The incubation period is 3–7 days.

Public health significance and occurrence of hand, foot and mouth disease

HFMD occurs worldwide, sporadically and in epidemics. The greatest incidence is in summer and early autumn. In tropical and subtropical countries, circulation of the virus tends to be year-round, with more outbreaks in the rainy season. Outbreaks occur frequently among groups of children in childcare centres and schools.

Reservoir of hand, foot and mouth disease viruses

Humans are the reservoir.

Mode of transmission of hand, foot and mouth disease viruses

HFMD is transmitted by direct contact with fluid from the vesicular lesions, direct contact with nose and throat discharges and faeces of an infected person, aerosol droplet spread and contaminated fomites (objects and surfaces).

Period of communicability of hand, foot and mouth disease

HFMD is communicable during the acute stage of disease from nose and throat secretions, for as long as there is fluid in the lesions. Viruses persist in the stools for several weeks.

Susceptibility and resistance to hand, foot and mouth disease

Everyone is susceptible to infection. Immunity to the specific virus may be acquired as a result of previous infection. Second attacks may occur with group A coxsackievirus of a different serotype.

Control measures for hand, foot and mouth disease

Preventive measures

There is no vaccine to protect against HFMD.

Control of case

Control of the case includes:

• exclusion from school of children with HFMD until all blisters have dried
• covering lesions on hands and feet, if possible, and allowing them to dry naturally
• avoiding piercing lesions, as the fluid within the blisters is infectious
• good handwashing, and cleaning and disposal of soiled articles
• avoiding close contact, such as kissing, hugging, or sharing eating and drinking utensils with others.

Control of contacts

Not applicable.

Outbreak measures for hand, foot and mouth disease

Individual cases and outbreaks of HFMD occur around the world.

Since 1997, large outbreaks of HFMD caused by enterovirus 71 have been reported, mainly in children, in east and South-East Asia.

In these outbreaks, most children had typical symptoms. However, a small number developed severe complications requiring hospitalisation or even causing death.