Lockdown could weaken natural defences against new viruses

PROLONGED periods of lockdown that cocoon the public from germs could leave people vulnerable to new viruses, a leading epidemiologist has warned.

Sunetra Gupta, professor of theoretical epidemiology at the University of Oxford, said she feared intense social distancing could actually weaken immune systems because people are not exposed to germs and so do not develop defences that could protect them against future pandemics.

The scientist rose to prominence in March after her team’s modelling created a best-case scenario where coronavirus arrived in the UK in December and spread quickly through the population creating “herd immunity”, already partly acquired through exposure to different strains of the virus. Her research rivalled that of Neil Ferguson, the Imperial College London professor whose worst-case scenario of 500,000 UK deaths encouraged the Government into lockdown.

Prof Gupta told The Sunday Tele

graph that while it was “unlikely” the three months of lockdown had compromised our immune system, there remained a possibility that it had had an impact. “This is a warning to not assume that the situation where we don’t suffer regular assaults by pathogens puts us in a better position,” she said.

“If we return to the point where we have no exposure, where we keep everything out and return to a state of existing as relatively isolated communities, we are like clumps of trees waiting to be set ablaze. That’s how things were in the age of pandemics.”

Prof Gupta said the 1918 Spanish flu pandemic which led to at least 50million deaths was “such a shocker” because so many of those who perished were fit and healthy people under 40.

“That was because in 1918 there had been no flu at all around in Europe for 30 years,” she said.

“We weren’t globally connected then as we are now. Effectively we used to live in a state largely similar to lockdown 100 years ago, which created the conditions for the Spanish flu to come and kill 50million people.”

She explained how “the fate” of any virus and our reaction to it depends on previous exposure to other strains of that pathogen.

“The kind of immunity that protects you against very severe symptoms and death can be acquired by exposure to related pathogens rather than the virus itself,” she said.