New Delhi | Jagran News Desk: While having spend months battling the coronavirus, terms such as ‘social distancing’, isolation, and quarantine have emerged out to be one of the most popular buzz words of the year 2020. Interestingly, the term ‘herd immunity’ has also been a significant part of the discussions centered around the topic of fighting with the outbreak.

How does herd immunity work?

The concept of herd immunity means that if a certain percentage of the population becomes immune to a certain disease-causing pathogen, then it prevents the infection from spreading to the rest of the population. Thereby, meaning that herd immunity can be achieved when enough people become immune after getting infected by the virus. It further transcends that a member of the group, of which certain section has been immuned, will not be able to infect another person. This is also considered as one of the ways through which the chain of spreading the infection is controlled and stopped and thus prevents it from reaching towards those who are vulnerable to the infection.


While the concerns regarding its success are still being raised, there have been various new studies emerging which throw light on how herd immunity against COVID-19 is difficult to achieve at this stage. One of these is a new study published in the Lancet which concludes that herd immunity is difficult to achieve at this stage based on estimates of seroprevalence which means the level of the pathogen in a population, in this case particularly, for the entire Spanish population.


'Largest Serological Study in Europe'

According to a report by The Indian Express, the new large-scale study conducted on the Spanish population concludes that out of the total population on which the study has been conducted, just 5% of it has developed antibodies in response to SARS-CoV-2, the virus that causes Covid-19, which implies that an estimated 95 percent continues to be susceptible to the virus. The study that is conducted on 66,805 participants found that seroprevalence for the entire country was 5% by the point-of-care test and 4.6% by immunoassay. 

The largest serological study conducted so far in Europe provides an estimate for the population of the entire country and captures the true number of infected COVID19 patients, which are not captured by laboratory tests. The study estimated that between 3,76,000 and 10,42,000 asymptomatic individuals went undetected in the non-institutionalised Spanish population, reports Indian Express.

Although the seroprevalence study provides data and information based on the previous exposure to the virus, the benefit of this study provided a line of arguments which emphasised on the fact that in the absence of a treatment or a vaccine against Covid-19, achieving herd immunity at this stage is not possible.

The study states that Herd immunity is difficult to achieve without accepting the collateral damage of many deaths in the susceptible population and overburdening of health systems, according to a report carried out by the Indian Express.

“In light of these findings, any proposed approach to achieve herd immunity through natural infection is not only highly unethical but also unachievable. With a large majority of the population being infection naive, virus circulation can quickly return to early pandemic dimensions in a second wave once measures are lifted,” German virologists Isabella Eckerle and Benjamin Meyr wrote in a separate commentary on the study published in The Lancet.

The data collected from Spain hence concludes that in a country that has reported community transmission, only an estimated 5% have developed antibodies in response to the virus.

Posted By: Simran Babbar