2021 Covid Outbreak In Delhi Shows Herd Immunity Against Delta Variant Difficult: Study

Since the first case of COVID-19 was detected in Delhi in March last year, the city experienced multiple outbreaks, in June, September and November 2020. The situation became worse in April this year, when daily cases increased from approximately 2,000 to 20,000 between March 31 and April 16.

The severe outbreak of COVID-19 in Delhi this year showed that the Delta variant of SARS-CoV-2 can infect previously exposed people through a different variant of the coronavirus, highlighting the challenges of reaching herd immunity against the variant, according to an international team of scientists.

The study, published in the journal Science on Thursday, also found that the Delta variant was between 30-70 per cent more transmissible than previous SARS-CoV-2 lineages in Delhi.

Since the first case of COVID-19 was detected in Delhi in March last year, the city experienced multiple outbreaks, in June, September and November 2020.

The situation became worse in April this year, when daily cases increased from approximately 2,000 to 20,000 between March 31 and April 16.