DUBLIN – The level of protection against the coronavirus among people who have already passed the Covid-19 decays “very quickly”, since the immunity provided by the antibodies could last only “a few months”, as revealed this Monday by an Imperial study College London.
The researchers analyzed the prevalence of antibodies in 365,104 adults in England between the last months of June and September.
In general, they found that the level of immunity fell by 26.5% during that period, while the decrease in protection was 39% for those over 75 years of age.
In contrast, those between the ages of 18 and 24 had the highest prevalence of antibodies and the level of immunity dropped by 14.9%.
This work also estimated that only 4.4% of all subjects had some degree of immunity to Covid-19 in September, when the number of infections began to rise in that region of the United Kingdom.
That figure stood at 6% between June 20 and July 13, and at 4.8% between July 31 and August 31, suggesting that immunity was “waning pretty quickly” and rising. the risk of reinfection.
“The main conclusion is that after the first wave (of coronavirus), there was still no evidence that the vast majority of the country’s population had protective immunity,” one of the study’s authors, Graham Cooke, explained in a statement.
That means that, although “we are seeing a decrease in the proportion of people who test positive,” there is a “vast majority” of individuals who “probably have not yet been exposed” to Covid-19, the expert noted.
“Consequently, the need for a vaccine is even greater if we want to create a high level of protection in the population,” Cooke added.
Likewise, the Imperial College investigation found that there were no significant changes in the level of immunity of the toilets between June and September, which could be due to the fact that in these contexts there is a “continuous transmission” or a “repeated exposure”, he observed Helen Ward, another of the authors of the work.
Regarding the so-called “herd immunity”, the expert warned that “we are still very, very far” from reaching a situation in which “the population will be protected by other people.”
“Even in the best of cases – in the first round of testing in this study – 94% of the population had no protection and now 95% have no evidence that they have antibodies,” Ward said.
“Our study shows that, over time, there is a reduction in the number of people who test positive for antibodies. It is not clear what degree of immunity the antibodies provide or how long this immunity lasts, ”Cooke continued.
Therefore, he recommended those with antibodies to continue to comply with the “recommendations”, which include measures of “social distancing” and the “use of masks where necessary.”