In one of the most puzzling and worrisome developments in the pandemic, scientists are racing to explain what’s happening in Manaus, Brazil, a city of 2.2 million at the edge of the country’s rainforest that is experiencing a second explosive outbreak, even though the first one was so bad it was thought to have produced herd immunity. As the situation deepens in Manaus, overwhelming the city’s health system again, researchers from Brazil and the United Kingdom yesterday said four possibilities might explain the recent dramatic resurgence, including variant SARS-CoV-2 viruses that arose in Brazil. They published their analysis yesterday in The Lancet. The city’s outbreak last spring stunned the world with images of dead bodies in the streets, people buried in cardboard caskets, and mass graves at local cemeteries. Seroprevalence studies over the summer estimated that 76% of Manaus residents had been infected, above the basic 67% herd immunity threshold.

 

Jair Ferreira Belafacce

Read more CIDRAP…