Serosurvey of human metapneumovirus infection in Croatia.

AIM To assess the seroprevalence of human metapneumovirus (hMPV) in Croatia. METHODS During 2005, a total of 137 serum specimens from Croatian patients aged from 6 days to 51 years, without respiratory symptoms, were collected at the Croatian National Institute of Public Health. The sera were examined using the indirect immunofluorescent assay. RESULTS The overall hMPV seropositivity rate in the samples tested was 77.4% (106/137). The seropositivity rate increased from 18.7% in children aged between 6 months and 1 year to 100% in people older than 20 years of age. The highest proportion of titers > or =1:512 was found in children aged from 1 to 2 years. CONCLUSION Our results suggest that hMPV infection is present in Croatia, with primary infection occurring in early childhood. This is the first study that indicates the circulation of hMPV in Croatia.