Viruses are blamed more often than bacteria in most US adults hospitalized with pneumonia. But according to the CDC's recently published "Etiology of Pneumonia in the Community" study neither viruses nor bacteria are detected in the majority of hospitalized pneumonia patients.
The study was conducted over a two-and-a-half-year period by a research team comprised of researchers from the CDC, three Chicago-area hospitals and two hospitals in Nashville. The researchers enrolled 2,320 adults in the study, all of whom were confirmed to have pneumonia.
Viruses were detected in 27 percent of those patients, and bacteria were detected in just 14 percent.
The researchers concluded that while the frequency with which respiratory viruses were detected in adults hospitalized with pneumonia was higher than previously documented, no discernible pathogen was detected in 62 percent of the participants.
"This illustrates the need for more sensitive diagnostic methods that can both help guide treatment at the individual level as well as inform public health policy for adult pneumonia at a population level," Seema Jain, MD, lead author of the paper and medical epidemiologist for the CDC's Influenza Division, said in a statement.