Study on herd immunity

A study conducted in Spain and published in the medical journal ‘Lancet’ on Monday had found that COVID-19 antibodies in Spain’s population “are insufficient to provide herd immunity”.

Herd immunity is usually achieved when immunity is built among the general population through some exposure to a virus or infection.

This was though Spain, one of the worst-hit countries, had more than 251,700 confirmed cases and 28,388 deaths.

Spain has the third-highest number of deaths relative to population in the world, with 607 deaths per million people, according to ‘Our World in Data’. The country’s population is 46.9 million.

The study authors had stated that herd immunity 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.

Airborne disease Meanwhile, the WHO has acknowledged that there is emerging evidence that the coronavirus can be spread by tiny particles suspended in the air.

The airborne transmission could not be ruled out in crowded, closed or poorly ventilated settings, it has said, adding that if the evidence is confirmed, it may affect guidelines for indoor spaces.

The WHO’s acknowledgement came as an open letter from more than 200 scientists accused the WHO of underestimating the possibility of airborne transmission.