Enterovirus: A virus that enters the body
through the gastrointestinal tract and thrives there, often moving on to attack the nervous system. The polioviruses are enteroviruses.
Enteroviruses are small viruses that are made of ribonucleic acid (RNA) and protein. In addition to the three different polioviruses, there are a number of non-polio enteroviruses that can cause disease in humans, including the Coxsackieviruses (Coxsackie A viruses and Coxsackie B viruses), echoviruses, and other enteroviruses.
Enteroviruses can be found in the respiratory secretions (for example, saliva, sputum, or nasal mucus) and stool of an infected person. Other people may become infected by direct contact with secretions from an infected person or by contact with contaminated surfaces or objects, such as a drinking glass or telephone. Parents, teachers, and child-care-center workers may also become infected by contamination of the hands with stool from an infected infant or toddler during diaper changes.
Infections caused by enteroviruses are most likely to occur during the summer and fall. Most people who are infected with an enterovirus have no disease at all. Infected people who become ill usually develop either mild upper respiratory symptoms (a "cold"), a flu-like illness with fever, and muscle aches, or an illness with rash. Less commonly, some people have aseptic or viral meningitis. Rarely, a person may develop an illness that affects the heart (myocarditis) or the brain (encephalitis) or causes paralysis. In early fall 2014, an outbreak of infection with a non-polio enterovirus known as enterovirus D68, or EV-D68, sickened many children across multiple U.S. states, many of whom required care in a hospital intensive-care unit. Enterovirus infections have been suspected to play some role in the development of type 1 diabetes, although they do not directly cause the condition. Newborns who become infected with an enterovirus may rarely develop an overwhelming infection of many organs, including the liver and heart, and die from the infection.
There are usually no long-term complications from the mild illnesses or from aseptic meningitis. Some patients who have paralysis or encephalitis, however, do not fully recover. People who develop heart failure (dilated cardiomyopathy) from myocarditis require long-term care for their conditions.
No vaccine is currently available for the enteroviruses, aside from poliovirus. General cleanliness and frequent handwashing are probably effective in reducing the spread of these viruses.
In 2014 there was a widespread outbreak of respiratory infections due to the Enterovirus D68 strain. This caused severe wheezing and coughing in affected individuals. In 2015 and 2016, the incidence of this virus has decreased dramatically.