As coronavirus cases continue to surge in the UK and in other parts of the world, new research may provide some explanation as to why infections show little signs of slowing down.
While people who have contracted the virus will have immunity for at least five months, a study of British healthcare workers by Public Health England indicated that those with antibodies may still be able to carry and spread the virus.
“This means even if you believe you already had the disease and are protected, you can be reassured it is highly unlikely you will develop severe infections,” Susan Hopkins, senior medical adviser at PHE and co-leader of the study, said.
“But there is still a risk you could acquire an infection and transmit (it) to others.”
While preliminary findings indicate reinfections of people with Covid-19 antibodies is rare, experts cautioned that those who contracted the disease in the first wave of the pandemic in the early months of 2020 may now be vulnerable to catching it again.
Experts are concerned those who have already contracted the virus may be lulled into a false sense of security, as people begin to show fatigue towards restrictions following nearly a year of measures to prevent the spread.
They believe the misconception may cause people to behave in a careless manner within the community, ignoring basic preventative measures such as social distancing.
"These data reinforce the message that, for the time being, everyone is a potential source of infection for others and should behave accordingly," Eleanor Riley, a professor of immunology and infectious disease at Edinburgh University, said.
Last week, health authorities in the UK said one in 50 people currently had the virus, while in London it was one in 30.
The UK recorded 48,682 new cases on Thursday, a week after it recorded a record 68,053 in a single day.
‘Major implications’ for vaccine rollout
Simon Clarke, an associate professor in cellular microbiology at Reading University, said the study "has major implications for how we can get out of the current crisis".
"This means that the vast majority of the population will either need to have natural immunity or have been immunised for us to fully lift restrictions on our lives, unless we are prepared to see many more people being infected and dying from COVID-19," he said.
Experts have also warned the vaccine may behave in a similar fashion, preventing serious illness but may still lead to the virus being transmitted.
WHO’s chief scientist Dr Soumya Swaminathan said last month there was no evidence vaccines were going to prevent people passing it onto others.
Epidemiologist Professor Mary-Louise McLaws from the University of NSW, who is a WHO advisor, reiterated her point, stressing there is “no guarantee” a vaccine will prevent transmission.
The UK’s chief scientific adviser Sir Patrick Vallance said he did not know if the current vaccine would work on the new South African and Brazilian strains.
Officials behind the Moderna vaccine believe they can develop new shots for the strains in several months by avoiding large clinical trials.
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