Hand, foot, and mouth disease
Hand, foot and mouth disease (HFMD) is a common infection caused by a group of viruses.[1] It typically begins with a fever and feeling generally unwell.[1] This is followed a day or two later by flat discolored spots or bumps that may blister, on the hands, feet, and mouth, and occasionally buttocks and groin.[2][3][4] Signs and symptoms normally appear 3–6 days after exposure to the virus.[5] The rash generally goes away on its own in about a week.[6] Fingernail and toenail loss may occur a few weeks later and these then regrow.[7]
Signs and symptoms
Common constitutional signs and symptoms of the HFMD include fever, nausea, vomiting, feeling tired, generalized discomfort, loss of appetite, and irritability in infants and toddlers. Skin lesions frequently develop in the form of a rash of flat discolored spots and bumps which may be followed by vesicular sores with blisters on palms of the hands, soles of the feet, buttocks, and sometimes on the lips.[16] The rash is rarely itchy for children,[5] but can be extremely itchy for adults. Painful facial ulcers, blisters, or lesions may also develop in or around the nose or mouth.[4][17][18] HFMD usually resolves on its own after 7–10 days.
Cause
The viruses that cause the disease are of the Picornaviridae family. Coxsackievirus A16 is the most common cause of HFMD.[9] Enterovirus 71 (EV-71) is the second-most common cause.[9] Many other strains of coxsackievirus and enterovirus can also be responsible
Transmission
HFMD is highly contagious and is transmitted by nasopharyngeal secretions such as saliva or nasal mucus, by direct contact, or by fecal-oral transmission.
Diagnosis
A diagnosis usually can be made by the presenting signs and symptoms alone.[17] If the diagnosis is unclear, a throat swab or stool specimen may be taken to identify the virus by culture.[17] The common incubation period (the time between infection and onset of symptoms) ranges from three to six days
Prevention
Preventive measures include avoiding direct contact with infected individuals (including keeping infected children home from school), proper cleaning of shared utensils, disinfecting contaminated surfaces, and proper hand hygiene. These measures have been shown to be effective in decreasing the transmission of the viruses responsible for HFMD.[17][19]Vaccine
A vaccine known as the EV71 vaccine is available to prevent HFMD in China as of December 2015.[20] No vaccine is currently available in the United States.[19]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.[17] 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 complications such as inflammation of the brain, inflammation of the meninges, or acute flaccid paralysis.[10] Non-neurologic complications such as inflammation of the heart, fluid in the lungs, or bleeding into the lungs may also occur.[10]
Complications
Complications from the viral infections that cause HFMD are rare, 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.[17] Viral or aseptic meningitis can occur with HFMD in rare cases and is characterized by fever, headache, stiff neck, or back pain.[10][17] 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.[16][17]Fingernail and toenail loss have been reported in children 4–8 weeks after having HFMD.[5] The relationship between HFMD and the reported nail loss is unclear; however, it is temporary and nail growth resumes without treatment.[5][21]
