Enteroviruses in Humans

Enteroviruses are significant ribonucleic acid (RNA) viral pathogens of humans with a worldwide distribution. Humans are the only known hosts for the enteroviruses. Their major route of infection is that of the faecal–oral route. In temperate climates enteroviral infection occurs primarily in the summer and early fall. Infants represent the majority of cases. Enteroviral infection results in viremia and prolonged gastrointestinal shedding of the virus. Enteroviral syndromes involve almost every organ system. Although the majority of infections are asymptomatic or result in a self-limited infection, fatalities do occur. Especially in neonates or individuals with B-cell immunodeficiencies. Advances in technology are providing improved understanding of their taxonomy, epidemiology and means of detection. Key Concepts: Enteroviruses have RNA genomes. The 5′NTR of the enteroviruses contain areas of conserved nucleotide identity. Originally five species were described within the genus: polioviruses, the group A and B coxsackievirus, the echoviruses and the numbered enteroviruses. Using modern molecular virologic methods the species have been redefined and novel members of the genus have been identified. Enteroviruses have a worldwide distribution and exhibit strong seasonality. The coding sequence of VP1 is used for the detailed analysis of enteroviruses. Humans are the sole reservoir for the enteroviruses. Infections by enteroviruses are significantly higher in infants. Faecal–oral transmission is the major mode of transmission of the enteroviruses. Infection results in prolonged shedding of the enteroviruses. Understanding the pathophysiology of the enteroviruses is based on the study of prototypic members of the genus: the polioviruses. The major determinant of susceptibility to the enteroviruses is the presence of the receptor required for viral attachment. Reverse transcription-polymerase chain reaction (RT-PCR) has replaced tissue culture and mouse inoculation for detection of the enteroviruses. RT-PCR is more sensitive and faster for the detection of the enteroviruses than tissue culture or mouse inoculation. RT-PCR diagnosis of enteroviral infections can significantly impact on patient care. Management of enteroviral infections is supportive in nature.