https://futurism.com/neoscope/brazilian-city-covid19-herd-immunity

Coronavirus cases in the city of Manaus (2 milion pop.), Brazil are on the decline — and experts suspect it’s because so many people already caught COVID-19 there that it’s now too hard for the virus to spread to new people.

If that’s the case, then Manaus would have achieved what’s called herd immunity, Popular Science reports, which is when so many people in an area build up a resistance or immunity to a disease that even those who didn’t get sick are protected as a result.

In a new preprint study, a team of U.S., U.K., and Brazilian scientists concluded that about 66.1 percent of residents of Manaus were infected with COVID-19 at some point, which falls in line with the percentages that epidemiologists previously predicted would be necessary to establish herd immunity.

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https://www.dailymail.co.uk/news/article-8665475/Brazilian-city-Manaus-dead-bodies-piled-refrigerated-trucks-herd-immunity.html
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The city, situated in the middle of a rainforest, was ravaged by the coronavirus at the start of the pandemic. It made international headlines four months ago when drone images captured bulldozers digging mass graves for Covid-19 victims.

Hundreds of bodies were stored in refrigerated trucks in scenes described by the city's mayor as a 'horror movie'.

But unlike the majority of Asia and Europe, the city never imposed a lockdown, strict social distancing rules or enforced face masks. Brazil's president was a vocal critic against the measures, which have crippled economies but saved lives.

Jarbas Barbosa da Silva, assistant director of the Pan American Health Organisation, claimed the peak of the outbreak was very strong, which may have produced some kind of 'collective immunity'.

But he added the city, in the Amazonas state, had 'paid a very large price'. Figures show it has suffered 3,300 deaths among the 1.8million residents — the equivalent of one in 500 residents being killed by the virus.