Echovirus 11 is a serotype of the echovirus group within the Enterovirus B species of the Picornaviridae family. It is a small, non-enveloped positive-sense RNA virus that transmits primarily through the fecal-oral route and respiratory secretions. Echovirus 11 infections range from asymptomatic carriage to serious illness, with neonatal sepsis-like disease being one of the most recognized presentations.
Virology and clinical features
Echovirus 11 contains a single-stranded RNA genome encoding a polyprotein that is processed into capsid proteins and replication enzymes. The virus replicates in the gastrointestinal and respiratory tract and is excreted in stool and saliva. Transmission occurs via contaminated hands, surfaces, and occasionally through water. After entering the host, the virus replicates in lymphoid tissue and can disseminate through the bloodstream. Most infections are mild or subclinical, causing fever, sore throat and sometimes rash. However, echovirus 11 is notable for its association with severe disease in newborns. Neonates exposed during delivery or shortly after birth can develop sepsis-like illness characterized by high fever, lethargy, hepatomegaly and coagulopathy. The virus has also been linked to myocarditis, hepatitis and aseptic meningitis in infants and adults. Diagnosis relies on reverse transcription polymerase chain reaction detection of viral RNA in cerebrospinal fluid, blood, stool or throat swabs. There is no specific antiviral therapy; treatment is supportive. Prevention focuses on strict hand hygiene in hospital nurseries and avoiding exposure during outbreaks. Seasonal patterns show higher incidence in summer and early autumn.
Outbreaks and notable cases
Echovirus 11 has caused several well-documented outbreaks, particularly in neonatal intensive care units. In the mid-2000s, clusters of echovirus 11 infections in Europe and North America led to severe neonatal hepatitis and coagulopathy with high mortality. More recent reports from Asia describe outbreaks of aseptic meningitis and myocarditis associated with this serotype. Genetic analyses reveal frequent recombination events, contributing to the emergence of new strains and occasional increases in virulence. Echovirus 11 has also been detected in environmental samples such as wastewater, suggesting widespread circulation in communities. Echovirus 11 is an important cause of neonatal disease and can also produce severe illness in older children and adults. Ongoing surveillance and strict infection control measures, particularly in perinatal settings, are essential for preventing transmission and managing outbreaks. Related Terms: Echovirus 6, Echovirus 9, Echovirus 30, Enterovirus D68, Human Parechovirus 1