In São Paulo and Rio Grande do Sul, underreporting tops 90 percent

Covid-19 testing. Photo: COVESP

A new study led by two of the most renowned Brazilian public universities, the University of São Paulo (USP) and the Federal University of São Paulo (Unifesp), shed light on Covid-19 underreporting in Brazil. Researchers found that over 5 percent of São Paulo’s population has developed Covid-19 antibodies — that is to say, has been infected with the novel coronavirus.

With these statistics, policymakers might be able to incorporate herd immunity levels into their thinking. Researchers have also concluded that underreporting in the city is as high as 91.6 percent — which means that only around 8.4 percent of the total number of cases have made it to the official statistics. With these statistics added to the official totals, the lethality rate in the city could be as low as 0.95 percent. As of writing, the official death rate in the state of São Paulo stands at around 7.7 percent.

Earlier this week, a similar study by the Federal University of Pelotas (UFPel) concluded that in Rio Grande do Sul only 0.2 percent of the population has been infected. The levels of underreporting in the state, however, are also around 90 percent. Scientists estimate that in order to potentially develop an acceptable level of herd immunity, between 70 and 90 percent of the population should present Covid-19 antibodies. However, the number of deaths also remains likely underreported too.