Co-infection with influenza and Legionella pneumophila was fatal in a model system created by researchers at the Max F. Perutz Laboratories (MFPL) of the University of Vienna and the Medical University of Vienna. The study was published in the journal Science.
"We expected that this [result] would be caused by the bacteria growing and spreading like crazy, but what we actually found was that the number of bacteria didn't change, which was a big surprise", said Amanda Jamieson, the lead author of the report and a research fellow in the Department of Microbiology, Immunobiology and Genetics of the University of Vienna.
One type of bacteria the immune system usually prevents from spreading and becoming harmful, Legionella pneumophila, can be left unchecked in patients infected with influenza virus, according to researchers. Because of the influenza virus suppresses the body's ability to repair tissue damage, damage to the lung tissue caused by a co-infection with flu and Legionella is not properly repaired and this may lead to fatal pneumonia, said researchers.
Investigators found that treatment with drugs that activate tissue repair pathways significantly improved the outcome. Investigators believe their findings could prompt the development of treatments to deal with co-infections of flu and bacteria, to improve patient outcomes and prevent permanent lung damage.