Human parechoviruses in infants with systemic infection.

Human parechoviruses (HPeVs) are RNA viruses related to neonatal sepsis, meningoencephalitis and other infections in young children. Little clinical and epidemiological information is available on these viruses. HPeVs were sought in cerebrospinal fluid from 397 infants aged less than 12 months from whom a sample was obtained to exclude meningitis or encephalitis from 2006 to 2009. HPeV infections were also tested in stool samples from 271 children aged less than 3 years old with gastroenteritis from November 2008 to March 2009. HPeV detection was by real-time polymerase chain reaction assay (region 5'UTR), followed by genotyping (region VP3/VP1). HPeVs were detected in the cerebrospinal fluid of nine infants (2.3%), one aged 6 months and eight aged 14-55 days old. All were admitted to hospital for febrile syndrome with abrupt clinical deterioration and suspected systemic infection without clear laboratory signs of meningeal inflammation. The same virus was detected in all the available nasopharyngeal aspirates, stool, and/or serum samples from each patient. At least eight of the nine cases were caused by HPeV3. HPeVs were detected in stool samples from 17 children (6.3%), the most prevalent types being types 1 and 3. In conclusion, HPeV infection is common in the Basque Country (Spain) and HPeV3 is a significant cause of hospital admission due to systemic infection in the first few months of life. In these patients, HPeVs should be investigated as part of routine tests for enterovirus.