Parainfluenza virus-associated hospitalizations occur most often among children aged 0 to 2 years, with a significant increase among children aged 1 to 2 years, according to study findings in The Journal of the Pediatric Infectious Diseases Society.
Researchers analyzed data from the National Respiratory and Enteric Virus Surveillance System to determine seasonal parainfluenza virus (PIV) trends from July 2004 to June 2010.
An estimated average of 232,774 pneumonia-related hospitalizations occurred. Children aged 0 to 5 months accounted for 50.8% of hospitalizations. PIV was associated with 5.5% of pneumonia hospitalizations, an estimated 10,186 annually. Of these, 54.4% were associated with PIV-3. Children aged 6 to 11 months had the highest number of PIV-associated pneumonia hospitalizations.
“The results indicate that the bulk of PIV-associated hospitalizations among children aged less than 5 years occurs from ages 0 to 2 years, with a marked increase among 1- to 2-year olds. This finding suggests that immunization would be most effective in preventing hospitalizations if the vaccine were administered early in the first year of life,” the study authors wrote.
Furthermore, according to the researchers, some vaccine candidates currently in development are directed at PIV-3 alone or in combination with RSV. However, results of the current study show that PIV-1 may be the better serotype for a vaccine.