Coxsackievirus

Coxsackieviruses are a few related enteroviruses that belong to the Picornaviridae family of nonenveloped, linear, positive-sense, single-stranded, RNA viruses, as well as its genus Enterovirus, which also includes poliovirus and echovirus. Enteroviruses are among the most common and important human pathogens, and ordinarily its members are transmitted by the fecal–oral route. Coxsackieviruses share many characteristics with poliovirus. With control of poliovirus infections in much of the world, more attention has been focused on understanding the nonpolio enteroviruses such as coxsackievirus.

Coxsackieviruses are among the leading causes of aseptic meningitis (the other usual suspected pathogens being echovirus and mumps virus).

The entry of coxsackievirus into cells, especially endothelial cells, is mediated by coxsackievirus and adenovirus receptor.

Coxsackieviruses are divided into group A and group B viruses based on early observations of their pathogenicity in neonatal mice. Group A coxsackieviruses were noted to cause a flaccid paralysis (which was caused by generalized myositis), while group B coxsackieviruses were noted to cause a spastic paralysis (due to focal muscle injury and degeneration of neuronal tissue). At least 23 serotypes (1–22, 24) of group A and six serotypes (1–6) of group B are recognized.

In general, group A coxsackieviruses tend to infect the skin and mucous membranes, causing herpangina, acute hemorrhagic conjunctivitis, and hand, foot, and mouth disease.

Both group A and group B coxsackieviruses can cause nonspecific febrile illnesses, rashes, upper respiratory tract disease, and aseptic meningitis.

The basic reproduction number (R0) for Coxsackievirus A16 (Cox A16) was estimated to a median of 2.50 with an interquartile range of 1.96 to 3.67.

Group B coxsackieviruses tend to infect the heart, pleura, pancreas, and liver, causing pleurodynia, myocarditis, pericarditis, and hepatitis (inflammation of the liver not related to the hepatotropic viruses). Coxsackie B infection of the heart can lead to pericardial effusion.