Enterovirus 68
Enteroviruses are associated with various clinical symptoms, including mild respiratory illness, febrile rash illness, and neurologic illness, such as aseptic meningitis and encephalitis.
Human enterovirus D68 (EV D68) is a unique enterovirus that shares epidemiologic and biologic features with human rhinoviruses . Classic enteroviruses have prominent summer-fall seasonality in temperate climates. EV68 has been associated almost exclusively with respiratory disease. New-onset wheezing or asthma exacerbation have been notable symptoms. Some cases have been severe enough to require hospitalization. There are no available vaccines or specific treatments for EV D68.
EV D68 was first isolated in California in 1962 from children with bronchiolitis and pneumonia. Since that time, only sporadic clinical cases have been reported. Infection of a large number of patients during a single season has only been identified recently. Small clusters of EV D68 associated with respiratory illness were reported in the United States during 2009–2010.
A large outbreak involving several hundred children occurred in Kansas City during August, 2014. Cases with similar symptoms have been reported throughout the Midwest and South including Missouri, Colorado, Georgia, Illinois, Iowa, Kansas, Kentucky, North Carolina, Ohio and Oklahoma. It is not known whether the increase in recognized cases is attributable to improved diagnostic tests or the emergence of a more pathogenic strain.
Viral culture has been available since the 1950s, although antisera for identifying an isolate as HEV68 were not widely available initially. During the past decade, improvements in nucleic acid amplification methods have increased the sensitivity of enterovirus detection and typing. FDA has approved two real time PCR multipathogen detection systems for clinical use (Luminex xTAG RVP and Idaho Technologies FilmArray Respiratory Panel). Both platforms incorporate broadly reactive primers that amplify RNA from human rhinoviruses and enteroviruses. Results are reported as "Entero-Rhinovirus" or "Human Rhinovirus/Enterovirus".
Partial sequencing of the HEV68 structural protein genes, VP4-VP2 or VP1 is considered to be the gold standard method of detection. EV-D68 can be specifically identified at a limited number of laboratories in the United States.
Enterovirus infections, including EV-D68, are not reportable in the United States, but laboratory detections of enterovirus and parechovirus types are reported voluntarily to the National Enterovirus Surveillance System, which is managed by The Centers for Disease Control (CDC). Participating laboratories are encouraged to report monthly summaries of virus type, specimen type, and collection date.
Specimen requirement is a nasopharyngeal swab transported in M6 viral media.