RSV Infection May Be Connected to Increased Pneumonia Risk

Patients, especially infants, who are infected with respiratory syncytial virus (RSV) may face an increased risk of developing pneumonia caused by Streptococcus pneumoniae, a recent study suggests.

The study, published online January 6, 2015, in PLOS Medicine, analyzed data collected between 1992 and 2009 on more than 700,000 hospitalizations for RSV and more than 16,000 hospitalizations for pneumococcal pneumonia (caused by S pneumoniae) among young children. The research team found that periods with high numbers of RSV hospitalizations were often associated with increases in pneumonia hospitalizations, with 20.3% of pneumococcal pneumonia cases in children younger than 1 year linked to high RSV activity. The researchers also found a significant decrease in RSV hospitalizations among children younger than 1 year after routine vaccination against S pneumoniae was introduced in 2000.

The study authors note that although they were unable to verify whether the patients were infected with both RSV and pneumococcal pneumonia, the associations they found between the 2 diseases, while not definitive proof that RSV increases the risk for pneumonia, do suggest that they interact in some way, particularly in infants.

“RSV is associated with increases in the incidence of pneumococcal pneumonia, particularly in young infants, and a percentage of RSV hospitalizations might be attributable to pneumococcus, based on post-PCV7 declines,” wrote the study authors.