Changes in the gut bacteria caused by antibiotics may increase the risks from flu infection by weakening the immune response, scientists have warned.
The work was done by Dr Andreas Wack and colleagues at the Francis Crick Institute, London, UK.
They found that about 80% of normal mice survive when they are infected with the flu. But if they had taken antibiotics before being infected, only a third survived.
Further tests indicated that ‘type I interferon signalling’ is vital for the immune response, and is negatively affected by changes in the microbiota driven by antibiotics.
Dr Wack said: "We found that antibiotics can wipe out early flu resistance, adding further evidence that they should not be taken or prescribed lightly.
"Inappropriate use not only promotes antibiotic resistance and kills helpful gut bacteria, but may also leave us more vulnerable to viruses. This could be relevant not only in humans but also livestock animals, as many farms around the world use antibiotics prophylactically.”
He added: “Further research in these environments is urgently needed to see whether this makes them more susceptible to viral infections."
The team went on to repopulate the animals’ gut bacteria after antibiotics through faecal transplant, and found this restored interferon signalling and improved resistance to the flu.
Dr Wack continued: "Taken together, our findings show that gut bacteria help to keep non-immune cells elsewhere in the body prepared for attack. They are better protected from flu because antiviral genes are already switched on when the virus arrives.”
The research was published yesterday (2 July) in Cell Reports.
Wack, A. et al. Cell Reports 2 July 2019 doi: 10.1016/j.celrep.2019.05.105
Leave a Reply