Hand-foot-and-mouth disease (HFMD) is a viral infection that causes outbreaks of blisters in or on the hands, feet, mouth and sometimes the buttocks and legs. Caused by the coxsackievirus and the enterovirus, the infection is most commonly found in children. But adults occasionally contract hand-foot-and-mouth disease, as well.
Children and adults who contract hand-foot-and-mouth disease usually have a feeling of tiredness that is combined with nausea, vomiting, loss of appetite, and a sore throat and/or fever. Infants and toddlers usually show signs of irritability that may include crying. Within a day or two, outbreaks of flat, painful sores and bumps begin to appear on the hands, feet and mouth (the latter of which are called herpangina). The sores, which also sometimes also appear on the legs, elbows and buttocks, may begin as a rash and eventually blister or become ulcers. The sores generally disappear in about a week, but during that time, they may crack and crust over.
Sometimes the symptoms of HFMD are so mild, a parent may contract the virus from their child and not even know it. Conversely, sometimes adults who contract the virus experience intense itchiness on and around the sores (whereas children rarely experience itchiness during HFMD outbreaks). Hand-foot-and-mouth disease is contagious, whether a person shows symptoms or not.
The incubation period of hand-foot-and mouth disease is three to six days, meaning it will take that long for a person to develop symptoms after being exposed to the virus.
As mentioned above, HFMD is caused by the enterovirus, which is highly contagious and spreads easily through things like saliva, mucus, and coughing and sneezing. Enteroviruses and coxsackieviruses also spread through infected feces, such as during a diaper change or if a young child gets infected feces on their hands and then touches objects that he or she and other children put into their mouths.
Hand-foot-and-mouth disease usually occurs in small epidemics, either in a household or in nursery schools or kindergartens. It most often spreads during the warmer summer and autumn months, and children under the age of 10 are most likely to become infected.
Coxsackievirus A16 and enterovirus 71 (EV-71) are the two most common viruses that cause HFMD, but there are several coxsackieviruses and enteroviruses that can cause the infection.
Most doctors can determine whether a child or adult has hand-foot-and-mouth disease just by looking at the sores that develop during infection. However, a doctor visit isn’t usually needed because there’s nothing physicians can do or prescribe to rid a patient of the infection. At this time, no antiviral treatment or vaccine is available. Instead, the following home care tips are recommended to help relieve symptoms of HFMD, which will disappear on its own in about a week:
There is currently no vaccine against hand-foot-and-mouth disease, but scientists are currently working on the development of such treatment.
Though HFMD is highly contagious, there are many steps you can take to help prevent the spread of the disease, which usually spreads within the first week of infection but can stay present in stools for weeks or even months.
Though rare, HFMD infections can cause neurologic and cardiac complications that can lead to death if left untreated. Viral and/or aseptic meningitis may appear during an HFMD infection and is characterized by fever, headache and stiff, painful muscles in the back and shoulders. Some children lose fingernails and toenails following an HFMD infection (especially those caused by coxsackievirus A6), though it is unclear why. And some hand-foot-and-mouth disease infections can cause encephalitis (swelling of the brain) and flaccid paralysis.
Call your doctor if your symptoms get worse or if they last longer than 10 days.
*Editor’s Note: Hand-foot-and-mouth disease should not be confused with foot-and-mouth disease, which is a viral infection that affects livestock and almost never infects humans.