No herd immunity: COVID antibodies transitory — study

BARCELONA — Only 5.2 percent of the Spanish population have developed antibodies to coronavirus, far below the numbers needed for herd immunity, a Spanish study showed on Monday.

The findings marked the conclusion of a three-month study into the prevalence of the virus, which involved testing almost 70,000 people across Spain three times in as many months, according to a report in The Telegraph, quoting an article published in the health journal The Lancet.

The scientists behind the study said: ”Despite the high impact of COVID-19 in Spain, prevalence estimates remain low and are clearly insufficient to provide herd immunity.”

”This cannot be achieved without accepting the collateral damage of many deaths in the susceptible population and overburdening of health systems. In this situation, social distance measures and efforts to identify and isolate new cases and their contacts are imperative for future epidemic control,” they added.

The study also discovered that 14 percent of people who tested positive for antibodies in the first test produced a negative result in the final test, which implies that immunity to COVID-19 can be short-lived. This phenomenon was most common among those who never displayed symptoms.

As a result, Dr Raquel Yotti, director of the Carlos III Health Institute which co-led the study, said: ”Immunity can be incomplete, it can be transitory, it can last for just a short time and then disappear.”

The loss of immunity was most common among people who never developed symptoms.

Speaking at a news conference, she appealed to Spaniards to remain prudent, particularly those who had recovered from the virus and considered themselves immune.

“We can’t relax, we must keep protecting ourselves and protecting others,” Yotti said.

The Spanish study came a month after the results of an antibody study in Switzerland involving 2,766 participants were published in The Lancet. It suggested that a low percentage of the population in Geneva tested positive for antibodies, despite the city being a hotspot for the disease.

Spain has registered 205,545 coronavirus cases and 28,385 deaths, according to health ministry data, making it one of Europe’s worstaffected countries.

International borders were opened at the beginning of July, providing a shot in the arm to the country’s struggling tourism sector.