Hand, foot and mouth disease Hand, foot and mouth disease is a human syndrome
caused by intestinal viruses of the picornaviridae family. Coxsackievirus A16 and Enterovirus
71 are the most common strains known to cause HFMD, but many other strains of coxsackievirus
or enterovirus are known to cause this viral syndrome.
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. HFMD is fairly common and typically affects infants and children, but may affect
immunocompetent adults on occasion. 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.
The usual incubation period is 3–6 days. 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. 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 available for HFMD. Signs and symptoms
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, but can be extremely itchy for adults. Painful facial ulcers, blisters,
or lesions may also develop in or around the nose or mouth. HFMD usually resolves on its
own after 7–10 days. Diagnosis
A diagnosis usually can be made by the presenting signs and symptoms alone. If the diagnosis
is unclear, a throat swab or stool specimen may be taken to identify the virus by culture.
The common incubation period (the time between infection and onset of symptoms) ranges from
three to six days. 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; 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. 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. Viral or aseptic meningitis can occur with HFMD
in rare cases and is characterized by fever, headache, stiff neck, or back pain. 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. Fingernail and toenail loss have been reported
in children 4–8 weeks after having HFMD. The relationship between HFMD and the reported
nail loss is unclear; however, is temporary and nail growth resumed without treatment.
Prevention No vaccine currently exists to protect individuals
from infection by the viruses that cause HFMD, but such vaccines are being developed. HFMD
is highly contagious and is transmitted by oropharyngeal secretions such as saliva or
nasal mucus, by direct contact, or by fecal-oral transmission. 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. Epidemiology
Hand, foot and mouth disease most commonly occurs in children under the age of 10.
Outbreaks In 1997, 31 children died in an outbreak in
the Malaysian state of Sarawak. In 1998, there was an outbreak in Taiwan,
affecting mainly children. There were 405 severe complications, and 78 children died.
The total number of cases in that epidemic is estimated to have been 1.5 million.
In 2008 an outbreak in China, beginning in March in Fuyang, Anhui, led to 25,000 infections,
and 42 deaths, by May 13. Similar outbreaks were reported in Singapore (more than 2,600
cases as of April 20, 2008), Vietnam (2,300 cases, 11 deaths), Mongolia (1,600 cases),
and Brunei (1053 cases from June–August 2008)
In 2009 17 children died in an outbreak during March and April 2009 in China's easternShandong
Province, and 18 children died in the neighboring Henan Province. Out of 115,000 reported cases
in China from January to April, 773 were severe and 50 were fatal.
In 2010 in China, an outbreak occurred in southern China's Guangxi Autonomous Region
as well as Guangdong, Henan, Hebei and Shandong provinces. Until March 70,756 children were
infected and 40 died from the disease. By June, the peak season for the disease, 537
had died. In 2011 Vietnam, by September 4 the disease
was reported to have claimed 98 lives, 75% of whom were children under 3 years old. Although
there was no official declaration of an outbreak, over 42,000 cases were reported. Over 10,000
new cases were recorded in the second half of August alone.
The World Health Organization reporting between January to October 2011 (1,340,259) states
the number of cases in China had dropped by approx 300,000 from 2010 (1,654,866) cases,
with new cases peaking in June. There were 437 deaths, down from 2010 (537 deaths).
In December 2011, the California Department of Public Health identified a strong form
of the virus, coxsackievirus A6 (CVA6), where nail loss in children is common.
In 2012 in Alabama, United States there was an outbreak of an unusual type of the disease.
It occurred in a season when it is not usually seen and affected teenagers and older adults.
There were some hospitalizations due to the disease but no reported deaths.
In 2012 in Cambodia, 52 of 59 reviewed cases of children reportedly dead (as of July 9,
2012) due to a mysterious disease were diagnosed to be caused by a virulent form of HFMD. Although
a significant degree of uncertainty exists with reference to the diagnosis, WHO report
states, "Based on the latest laboratory results, a significant proportion of the samples tested
positive for enterovirus 71 (EV-71), which causes hand foot and mouth disease (HFMD).
The EV-71 virus has been known to generally cause severe complications amongst some patients."
Hand, foot and mouth disease infected 1,520,274 people with 431 deaths reported up to end
of July in 2012 in China. History
Hand, foot and mouth disease cases were first described in New Zealand in 1957.