In the United States, coxsackievirus A16 is an important cause of hand, foot, and mouth disease (HFMD). More recently, coxsackievirus A6 has been implicated as the cause of outbreaks and sporadic cases in the United States and internationally. In the Asia-Pacific region, enterovirus 71 is a common etiologic agent.
Direct person-to-person contact with the saliva, nose and throat secretions, vesicle fluid, or stool of an infected person.
A common illness in young children, HFMD has a worldwide distribution. Outbreaks often occur during summer and early fall in the United States. Large outbreaks in Cambodia, China, Japan, Korea, Malaysia, Singapore, Thailand, Taiwan, and Vietnam have been reported in the past 2 decades. Seasonal patterns in Asia vary between climatic zones. In temperate Asia, including mainland China, cases tend to peak during the early summer.
Incubation period is 3–6 days. Patients usually present with fever and malaise, followed by sore throat and the appearance of vesicles in the mouth (typically anterior, involving the buccal mucosa, tongue, or hard palate) and a peripheral rash, often papulovesicular, on the hands (palms) and feet (soles). In some cases, particularly with coxsackievirus A6 infection, rash may be more widespread, the lesions enlarging and coalescing to form bullae. Lesions usually resolve within about a week. Onychomadesis (shedding of the nails) and desquamation of the palms or soles can occur during convalescence. Rare complications include aseptic meningitis and encephalitis. In a small proportion of children with enterovirus 71 infection in Asia, severe manifestations, including central nervous system disease and death, have occurred.
Diagnosis is usually clinical. Confirmatory laboratory testing using RT-PCR assays is available and performed for atypical or severe cases. Preferred samples for testing include vesicle fluid, throat or buccal swabs, or stool. RT-PCR assays to detect enterovirus RNA are available at many commercial or reference laboratories. The CDC Picornavirus Laboratory performs enterovirus testing and typing in consultation with state or local health departments: www.cdc.gov/non-polio-enterovirus/lab-testing/index.html.
Supportive care.
Avoiding close contact with infected people, maintaining good hand hygiene, and disinfecting potentially contaminated surfaces, including toys.
CDC website: www.cdc.gov/hand-foot-mouth
Holly M. Biggs