In all, there are 68 viruses within the Enterovirus genus that are known to infect humans. It must be noted that the nomenclature of this genus is a mess. This page will focus on the non-polio causing enteroviruses. For a profile of poliovirus please see go to the site created last year by Nina and Bill.
Most enterovirus infections are subclinical, especially in young children, but when they do cause clinically apparent disease, they can cause a wide range of clinical syndromes and can involve many of the body systems. Non-polio enteroviruses most commonly cause rashes, upper respiratory tract infections (URTIs) and summer colds. They can also cause neurological disease and are the most common cause of meningitis. In general, Coxsackievirus infections tend to cause more severe complications than echovirus infections resulting in: carditis, pleurodynia, herpangina, hand-foot-and-mouth disease (LINK), and occasionally paralysis, all of which are rarely seen in echovirus infection.
Recently there have been outbreaks of Enterovirus 71 , which have caused fatal cases of hand-foot-mouth disease in Taiwan.
Enteroviruses first begin replication in the gastrointestinal or respiratory tract, then enter the bloodstream where they can affect other tissues and organs.
Human enteroviruses are found worldwide, and humans are the only natural hosts. Enteroviruses are transmitted primarily by the fecal-oral route, but respiratory spread is possible with some of the Coxsackieviruses, which can cause URTIs. Young children are most at risk for infection, which is usually inapparent, while older children and adults are more at risk for complications. In less developed areas of the world, most children become infected early in infancy, while in the developed world, first infection often does not occur until adolescence. Boys are more susceptible for the development of clinically apparent diseases than are girls. The virus may be shed from the stool for may weeks. Enteroviruses have been found in water, soil, vegetable, and shellfish. Thus, they may also be transmitted by contact with contaminated food or water. Enteroviruses are associated with seasonal infections, with epidemics peaking in late summer/early autumn in temperate climates, and epidemics occurring year-round in tropical climates.
Currently there are no vaccines available for the non-polio enteroviruses. Prevention includes improved sanitation and general hygiene, in addition to quarantine and possible closing of schools in the case of recognized epidemics. In addition to having no vaccines, there are no specific antiviral agents currently available for clinical use (though some candidates are in clinical trials LINK to update page). Treatment is symptomatic and focuses on complications associated with infection. Administration of immune globulin may be useful in preventing severe disease in immunocompromised individuals or in those with life-threatening disease.