A new study in mice by researchers from the Francis Crick Institute in London, United Kingdom, suggests that antibiotics could actually also “prime” the lungs for viral infections.
The researchers’ findings, which feature in the journal Cell Reports, also show that gut bacteria drive a type of protein signalling that helps the cells that line the lungs keep the flu virus from spreading.
Antibiotic use, it seems, interferes with this protein signalling and thus impairs this first line of defence. “We found that antibiotics can wipe out early flu resistance, adding further evidence that they should not be taken or prescribed lightly,” explains lead researcher Andreas Wack, Ph.D.
In the new study, Wack and team used a group of mice with healthy gut bacteria at baseline. Over 4 weeks, they gave these mice a mix of antibiotics through their drinking water before infecting them with the flu virus.
‘‘They also infected some mice that they had not treated with the antibiotic mix so that they could compare the outcomes. The team noticed that approximately 80% of the untreated mice with healthy gut bacteria survived the infection with the flu virus.
Yet, of the mice who had previously received the antibiotic mix, only one-third were able to survive the viral infection. “Inappropriate use [of antibiotics] not only promotes antibiotic resistance and kills helpful gut bacteria, but may also leave us more vulnerable to viruses,” says Wack.
“This could be relevant not only in humans but also livestock animals, as many farms around the world use antibiotics prophylactically. Further research in these environments is urgently needed to see whether this makes them more susceptible to viral infections,” he argues.