December 3, 2023
A new species can infect more and kill less

A new species can infect more and kill less

large amount of micron spikes It’s an extraordinary fact to be investigated in Brazil, say scientists condition. The new type of coronavirus was discovered in South Africa, and it contains 50 mutations. About 30 of them are found in the so-called spike protein, the protein that allows the virus to enter human cells and is one of the main targets of vaccines against COVID-19.

Illustrative image of COVID-19 09/11/2020 REUTERS/Dado Rovich

Illustrative image of COVID-19 09/11/2020 REUTERS/Dado Rovich

Photo: Reuters

The first hypothesis for the many mutations (three times that seen in the delta variant) is that they developed in an immunocompromised patient who had long harbored the alpha variant in South Africa. Tests detect Ômicron because it does not contain a specific gene – like alpha, according to international experts. “We’ve never seen a variant with so many mutations,” says Professor Amilcar Tannuri, coordinator of the Virology Laboratory at the Federal University of Rio de Janeiro (UFRJ).

Tanuri says he supports the hypothesis that emerging viruses tend to attenuate as they spread between humans. With each mutation, there is a tendency for it to become more transmissible and less lethal.


The first reports from doctors in South Africa indicate that the virus is spreading quickly, but without a large number of serious cases. “This observation in South Africa is still experimental, but it supports the hypothesis of weakening the virus and increasing its transmissibility,” says the UFRJ coordinator.

“In Brazil, we still don’t have access to a micron variant to study,” Tanori says. “Once it is detected in the country, the first thing to do is isolate the virus and put it in contact with the sera of patients vaccinated here in Brazil who are also infected with the delta type,” says the virologist.

In this way, it will be possible to find out if overcoming other coronaviruses confer some immunity (mutual protection) against the micron. The second question that will need to be answered is how the new variable will behave. In other words: if it were to replace delta in Brazil, as it appears in Africa. Since the virus can be transmitted faster than the competitor, it wins the dispute. The first continues to spread, but to a lesser extent. It’s worth noting that Delta ended up not causing an increase in cases in Brazil – according to many experts, due to a combination of vaccination and health measures.


According to Tanori, several groups have published the sequences of viruses found in people who have had persistent or prolonged infection with the previous variants. In a study conducted in the UFRJ with twenty such patients, researchers observed that the accumulation of mutations in the spike protein was proportional to the time the virus remained in the individual.

For epidemiologist Cesar Victora, professor emeritus at the Federal University of Pelotas (UFPel), reports from doctors in South Africa may be a sign that the coronavirus is evolving like many other viruses that are initially very aggressive, but become weak over time. “This could happen, and it could be good news, but it’s still too early to tell,” he says.


The specialist believes that the country needs to expand the changing monitoring system. “We have to increase the capacity. We still have a little sequencing. The alternative may already exist and not yet discovered,” says Coordinator of the Scientific Committee of the Todos Pela Saúde Institute.