Respiratory syncytial virus was detected in 7.4% of older adults with moderate-to-severe influenza-like illness, according to recent data.
“Our study illustrates the importance of RSV and other respiratory viruses as causes of serious respiratory illness affecting older adults around the globe,” the researchers wrote in The Journal of Infectious Diseases. “Thus, in addition to influenza prevention, prevention of viral infections such as RSV could decrease severe illnesses in the elderly, particularly those at increased risk of the complications of viral respiratory tract infections.”
The researchers conducted a laboratory-based epidemiological study using samples collected from the INFLUENCE65 clinical trial, a randomized trial of adjuvanted vs. nonadjuvanted influenza vaccine in adults aged at least 65 years across 15 countries. Participants provided nose and throat swabs if they developed influenza-like illness. They also completed a questionnaire to assess the severity of symptoms. In this study, the researchers tested 556 of the collected samples from participants who fulfilled criteria for moderate-to-severe influenza-like illness.
Among the RSV detections (7.4%), all but two were single infections. The prevalence of RSV ranged from 2% in Mexico to 17.1% in Czech Republic. There was a significant association between country and RSV detection. RSV was detected in 7.1% of episodes with pneumonia, 12.5% of episodes with hospitalization and 6.7% of episodes with maximum influenza severity score >2.
Among the 556 samples, 320 had evidence of any virus. The most frequently reported respiratory viruses were influenza A (n=104), rhinovirus/enterovirus (n=82), RSV (n=41), coronavirus (n=32) and human metapneumovirus (n=32). There were 11 cases of multiple viral infections, in which influenza A or influenza B and/or rhinovirus/enterovirus were implicated for all but one.
“This is the first global study to our knowledge providing data on RSV disease in the elderly,” the researchers wrote. “Consistent with reports from North America, our study confirms that RSV is an important respiratory pathogen in older adults.”
Disclosure: The study was funded by GlaxoSmithKline, and some of the researchers report various financial ties to GlaxoSmithKline. See the study for a full list of financial disclosures.