Hand, foot, and mouth disease

Overview

Hand, foot, and mouth disease (HFMD) is a common childhood disease that is generally mild and self-limiting. HFMD is endemic in Singapore and can affect all ages, particularly children below 5 years old.

Disease epidemiology

HFMD is a common childhood viral illness that is mild and self-limiting. Majority of infections occur at the pre-school age, although infection can also occur in adults.

Infection leads to a specific immunity against the particular virus that caused the current infection; however, reinfection can occur through a different virus from the enterovirus group.

Pathogen(s)

Numerous members of the Enteroviruses group of the family Picornaviridae, e.g. coxsackievirus, echovirus, enterovirus (EV)-A71.

Transmission

HFMD transmits via the faecal – oral route, direct contact with respiratory secretions, saliva or vesicular fluid from rash or indirectly via contaminated surfaces.

Incubation period: Typically, 3 to 5 days; ranging from 2 to 14 days.

Infectious period: Few days before onset of prodromal symptoms to about 1 week from the onset of illness. The maximum excretion period is 3 to 4 weeks from the nasopharynx, and 6 to 12 weeks from faeces of the infected person.

Clinical features

A person with HFMD usually presents with the following:

•  Fever

• Sore throat

• Rash (flat or raised red spots) or small blisters on palms of hands, soles of feet, or buttocks

• Mouth ulcers

• Poor appetite

• Lethargy

The clinical presentation may vary between individuals, and at different stages of the disease. About 50% to 80% of HFMD infections are asymptomatic.  

Complications are rare, but include:

• Myocarditis

• Pulmonary oedema

• Acute respiratory distress syndrome

• Viral pneumonitis

• Aseptic meningitis

• Brainstem encephalitis

• Acute flaccid paralysis

• Secondary bacterial infection

Some cases may have no rash but only ulcers, in which case the patient is labelled as having herpangina, which is caused by the same group of enteroviruses. There may be symptoms of cough or rhinitis.

An important differential diagnosis is herpes simplex stomatitis, which has ulcers more in the anterior mouth, and is visible externally.

Risk factors

Risk factors include:

• Children under the age of 5

• Children in congregated settings (e.g. childcare or preschool settings)

Diagnosis

HFMD is typically diagnosed based on its clinical presentation.

In cases with atypical presentation or for public health investigations, laboratory tests through detection of viruses of the Enteroviruses group in throat or vesicles swab through Polymerase Chain Reaction (PCR) or virus isolation may be considered.

Treatment and management

HFMD is usually mild and self-limiting. No specific treatment is available; however, treatment can be given to relieve the symptoms of the disease.

Patients with signs and symptoms of severe disease or complications should be referred to hospital for further management (e.g. prolonged fever, poor feeding, and lethargy).

Precaution, prevention, and control

Contact management

No specific management of contacts is required.

Vaccination

No vaccines against enteroviruses, including those that cause HFMD, are currently available.

Notification

HFMD is not a legally notifiable disease in Singapore. Please refer to the Infectious Disease Notification for more information. 

Resources

Please refer to the Weekly Infectious Diseases Bulletin for the average daily number of polyclinic attendances for HFMD.

For more information on HFMD, please refer to the World Health Organization website.

For general travel advisory, please refer to Health Advice for Travellers.