Bugs starved of nutrition during infection become resistant to nearly every type of antibiotics, even if they are exposed to some of them for the first time.
What causes starvation-induced antibiotic resistance, and how can it be overcome? Researchers came up with surprising answers.
“A chief cause of the resistance of biofilms is that bacteria on the outside of the clusters have the first shot at the nutrients that diffuse in,” said Pradeep Singh, associate professor of medicine and microbiology at the University of Washington.
“This produces starvation of the bacteria inside clusters, and severe resistance to (their) killing,” added the senior study author, the journal Science reports.
Biofilms are clusters of bugs encased in a slimy coating, found in human tissues where they cause disease, according to a university statement.
For example, biofilm bacteria grow in the scabs of chronic wounds and the lungs of patients with cystic fibrosis. They tolerate high levels of antibiotics without being killed.
“Bacteria become starved when they exhaust nutrient supplies in the (infected) body, or if they live clustered together in groups known as biofilms,” said study co-author Dao Nguyen, assistant professor of medicine at Montreal’s McGill University.