Coinfection did not result in severe cases, although it may generate more threatening strains

Published in late February by the Virus Research Journal, an article written by Brazilian researchers flared national and international debate about the possibility of co-infection caused by different variants of the new coronavirus (SARS-CoV-2), that is, the possibility of individuals developing more than one strain at the same time.

By performing genetic sequencing of the viruses identified in 92 patients of both genders and between 14 and 80 years of age, the research aimed to investigate which variants were circulating in the Brazilian state of Rio Grande do Sul. Five different strains were identified. The major finding, however, was that 2 patients developed more than one viral strain simultaneously, thus providing the first evidence ever that COVID-19 coinfection may occur.

The two patients were female, 32 and 33 years of age, and had minor symptoms of the disease. Their recovery did not require inpatient care, hence not upholding the hypothesis that coinfection would necessarily lead to a more severe form of infection. One of the patients developed two of the oldest lineages of the virus that have been circulating since the pandemic outbreak, but the other one developed a more recent strain, the one called P2, which originated in Rio de Janeiro and has been associated with increased contagion rate.

Given the lack of scientific evidence about coinfection leading to more severe forms of COVID-19, concerns now turn to the possible emergence of new coronavirus variants that may be more transmissible and lethal for being based on viral recombination, a process that has already been investigated for other RNA-genome-based viruses such as SARS-CoV-2. In addition to the known variants, recombinant viruses may become a greater source of concern with respect to the control of the pandemic and how effective vaccines are.

There is no reason for panic, though. These discoveries only emphasize the essentialness of transmission-reducing measures such as face masks, social distancing and hand hygiene. In the meantime, vaccination programs are being run all over the world and have proven to be successful. Vaccines used in Brazil have shown their efficacy against the new viral strains, such as the Amazon strain (E484K). In addition to immunization, several studies have been conducted to develop effective therapies and medicines against this disease.