The average age of the first patients diagnosed with Covid-19 in Brazil, 39 years old, was lower than that observed in other countries. Associated with the fact that, in the initial phase of the epidemic, most of these patients belonged to the highest social classes, this may have contributed to the fact that the country recorded a hospitalization rate equivalent to half the international average – 10% against 20% from other countries.
The conclusions are from an international study, led by Brazilian researchers. The preliminary results of the research, supported by the São Paulo State Research Support Foundation (Fapesp) under the Joint Brazil-United Kingdom Center for Discovery, Diagnosis, Genomics and Epidemiology of Arbovirus (CADDE), were described in an article published in medRxiv platform, still in pre-print version (without peer review).
“The economic condition of these first infected patients allowed them to have greater access to diagnostic tests, for example, initially facilitating social isolation and reducing contagion,” said the Fiocruz researcher and one of the study’s authors, Julio Henrique Rosa Croda.
The researchers analyzed the epidemiological, demographic and clinical characteristics of confirmed cases of Covid-19 during the first month of the epidemic in Brazil. For this, they mainly used the REDCap database, created by the Ministry of Health at the beginning of the disease outbreak to report cases.
Data analysis indicated that, between February 25 and March 25, 1,468 cases of Covid-19 were confirmed in Brazil, of which almost half (48%) were between 20 and 39 years of age. Of the total number of cases registered at the time, 10% required hospitalization and had cardiovascular diseases and hypertension as risk factors associated with hospitalization.
“It may be that the average age of patients with Covid-19 hospitalized in Brazil is lower than the world average because they would have a higher prevalence of comorbidities compared to the population in the same age group in other countries. But that hypothesis has not yet been confirmed ”, says Croda.
The lower average age of infected and hospitalized patients in Brazil compared to other countries may also be related to the fact that this age group, between 20 and 39 years of age, represents a significant portion – 32% – of the Brazilian population, ponder the researchers.
To assess whether the first reported cases of SARS-CoV-2 infection (new coronavirus) were related to the patients ‘socioeconomic profile, the researchers analyzed the cases recorded in the São Paulo metropolitan region, based on geolocation data from the patients’ addresses . The analyzes revealed that the regions with the highest average per capita income had higher testing rates.
“We found that there is a socioeconomic disparity in access to the diagnostic test for infection with the new coronavirus in Brazil that persists as the number of cases of the disease has expanded,” says Croda.
The researchers also noted that, during the first month of the epidemic, only 33.1% of cases were confirmed in public health laboratories and the rest in private laboratories. “Initially, the disease was more restricted to the richest population in the country and, at the end of March, there was a transition and started to affect the poorest population”, analyzes Croda.