RIO DE JANEIRO, BRAZIL – The mortality rate of Covid-19 may be lower than current estimates or even those published in early studies of the disease. The proportion of deaths among people infected with the coronavirus is 0.33 percent among the Rio Grande do Sul population, according to the second round of research that seeks to assess the real spread of the epidemic.
The research project, Epicovid19, is headed by Ufpel (Federal University of Pelotas) and the Rio Grande do Sul government. The tests were conducted on April 27th, in a sample with 4,500 people from Rio Grande do Sul, which has a population of approximately 11.3 million. The research will include two further stages.
There will also be a nationwide study, which has been held back somewhat, but is expected to begin on May 5th and intends to test 33,250 people in each of its rounds, which will be held every two weeks.
The study aims to estimate the percentage of people with antibodies to the coronavirus (a number closer to the total number of infections), measure the rate of spread of the disease, detect the portion of asymptomatic infections, and effectively determine how many it kills. With these data, it will be possible to study more accurately the progress of the epidemic, and to plan its containment.
According to the second round of the study in Rio Grande do Sul, about 0.13 percent of the population have been infected and have already developed antibodies (which take at least five days). In every million inhabitants of Rio Grande do Sul, there are approximately 1,300 people infected (having antibodies), for an official record of 108 cases per million inhabitants (only the most severe cases are recorded, in practice).
For each reported case, there could be from 5 to 26 unreported cases, many of which are asymptomatic. Since infection numbers are still relatively low in Rio Grande do Sul, estimates are not yet accurate. For instance, the total number of people infected (with antibodies) could range from 5,650 to 32,770, with the most likely number being 15,066.
Source: Folhapress