Gene behavior distinguishes viral from bacterial infections

New approach could gauge response to flu vaccine

Flu virus and MRSA bacteria

CASING A CULPRIT  Certain gene behavior changes in people can reveal whether an infection is caused by a virus, such as the H1N1 influenza virus (left), or bacteria, such as methicillin-resistant Staphylococcus aureus, or MRSA (right). 

NIAID/Flickr (CC BY 2.0)

Coughs, fevers and green mucus can accompany an infection, but most of the time, doctors can only guess whether the culprit is bacterial or viral.