The results show that 95% of the Spanish population remains vulnerable to the virus. Herd immunity is achieved when a sufficient population has been infected or vaccinated with a virus or bacteria to stop circulation.
The European Center for Disease Control announced to CNN that Spain’s research into a nationally representative sample of more than 61,000 participants was the largest study to date among a dozen coronavirus serological studies conducted by European nations.
“Given these results, each proposed approach to achieving herd immunity from natural infections is not only highly unethical but also unreachable,” said Lancet commentary Isabella Eckerle, director of the Geneva Center for Emerging Virus Diseases, and Benjamin Meyer Virologist at the University of Geneva.
Doctors are not sure whether antibodies to the corona virus mean that someone cannot be re-infected. It is not clear how long or how well antibodies protect people from the virus.
Spain’s peer review study started in April while the nation remained strictly locked and was carried out by leading government research and epidemiological agencies.
“The relatively low seroprevalence observed in connection with an intense epidemic in Spain could serve as an indication of other countries. It is currently difficult to achieve herd immunity without the collateral damage of many deaths in the vulnerable population and the overloading of health systems to accept “is the report.
The lead author of the Spanish study, Marina Pollán, director of the National Center for Epidemiology, told CNN: “Some experts have calculated that around 60% of seroprevalence could mean herd immunity, but we are still far from achieving this number.”
Spain was one of the most coronavirus countries in Europe, with more than 28,000 deaths and 250,000 deaths.
The Lancet published results from the first phase of the Spanish study, which ran from April 27 to May 11 and showed a 5% nationwide antibody prevalence.
However, the metropolitan area of Madrid most affected by Covid-19 had a prevalence of more than 10% and the densely urban Barcelona had a prevalence of 7%, while many other coastal provinces had much lower rates.
Similarly, the Geneva prevalence in the Swiss study conducted from April to early May was 10.8%, the Lancet reported.
“Since a large majority of the population is incapable of infection, virus circulation in a second wave can quickly return to early pandemic dimensions once the measures are lifted,” commented Lancet, Eckerle and Meyer, commenting on the results.
The results of the second study phase in Spain were published on June 4 and show a national prevalence of 5.2%, only slightly higher than in the first phase. The results of the third and final phase were published on Monday. They showed that the national prevalence remained at 5.2%, said Pollán.