This study just came out on the variant of the coronavirus that evolved in Manaus but is already all over the world:

somewhere between 1.4 and 2.2 times more transmissible than other lineages of coronaviruses.

They estimate that in 100 people who were infected with non-P.1 lineages in Manaus last year, somewhere between 25 and 61 of them could have been reinfected if they were exposed to P.1
Plus there are reports that it hits younger people hard - average age of the dead has dropped as much as 20 years in some places.

Brasil's health care system is about to collapse, meaning run out of beds not only in hotspots, but everywhere at once - no place to transfer patients. The next month is predicted to be horrible - as if things were not already horrible. But soon it will happen to other countries too. The virus is not done yet.