HFMD is a common and highly contagious viral infection that typically causes a mild febrile illness followed by a maculopapular rash that may involve the skin of the hands, feet, and oral cavity.^[4][5] HFMD is fairly common and typically affects infants and children, but may affect immunocompetent adults on occasion.^[5] The viruses that cause HFMD are spread through direct contact with the mucus, saliva, or feces of an infected person. HFMD typically occurs in small epidemics in nursery schools or kindergartens, usually during the summer and autumn months.^[5] The usual incubation period is 3–6 days.^[6]

HFMD should not be confused with foot-and-mouth disease (also known as hoof-and-mouth disease), a distinct viral disease known to affect sheep, cattle, and swine (both diseases are caused by members of the picornaviridae family) but transmission to humans is exceptionally rare.^[7][8] Most cases of the syndrome go away on their own and require no treatment other than to provide symptomatic relief. There is no cure or vaccine currently available for HFMD but one is under development.^{[citation needed]}

Common constitutional signs and symptoms of the HFMD include fever, feeling tired, malaise, loss of appetite, and irritability in infants and toddlers. Skin lesions frequently develop in the form of a maculopapular rash followed by vesicular sores with blisters on palms of the hands, soles of the feet, buttocks, and sometimes on the lips. The rash is rarely itchy for children,^[6]but can be extremely itchy for adults.^[9] Painful facial ulcers, blisters, or lesions may also develop in or around the nose or mouth.^[5][10][11] HFMD usually resolves on its own after 7–10 days.^[10]

Diagnosis

A diagnosis usually can be made by the presenting signs and symptoms alone.^[10] If the diagnosis is unclear, a throat swab or stool specimen may be taken to identify the virus by culture.^[10] The common incubation period (the time between infection and onset of symptoms) ranges from three to six days.^[6]

Treatment

Medications are usually not needed as hand, foot and mouth disease is a viral disease that typically gets better on its own. Currently, there is no specific curative treatment for hand, foot and mouth disease.^[10] Disease management typically focuses on achieving symptomatic relief. Pain from the sores may be eased with the use of analgesic medications. Infection in older children, adolescents, and adults is typically mild and lasts approximately 1 week, but may occasionally run a longer course. Fever reducers and lukewarm baths can help decrease body temperature.

A minority of individuals with hand, foot and mouth disease may require hospital admission due to uncommon neurologic complications such as (inflammation of the brain, inflammation of the meninges, or acute flaccid paralysis) or due to non-neurologic complications such as inflammation of the heart, fluid in the lungs, or bleeding into the lungs.^[3]

Complications

Complications from the viral infections that cause HFMD are uncommon, but require immediate medical treatment if present. HFMD infections caused by Enterovirus 71 tend to be more severe and are more likely to have neurologic or cardiac complications including death than infections caused by Coxsackievirus A16.^[10] Viral or aseptic meningitis can occur with HFMD in rare cases and is characterized by fever, headache, stiff neck, or back pain.^[3][10] The condition is usually mild and clears without treatment; however, hospitalization for a short time may be needed. Other serious complications of HFMD include encephalitis (swelling of the brain), or flaccid paralysis in rare circumstances.^[10]

Fingernail and toenail loss have been reported in children 4–8 weeks after having HFMD.^[6] The relationship between HFMD and the reported nail loss is unclear; however, it is temporary and nail growth resumes without treatment.^[6][12]