They warn that new variants can become dominant within weeks and cause exponential growth

Without drastic traffic restrictions, the new variants of Sars-Cov-2 could spread quickly and trigger a second wave larger and more deadly than that of a year ago, experts warn.

The British variant already has community circulation in the metropolitan area of ​​Buenos Aires (Amba). “If the trend continues, in about five to six weeks it could account for more than 50 percent of cases in this region,” says Humberto Debat, virologist at the National Institute of Agricultural Technology (Inta) in Cordoba.

The specialist, who is part of the Pais consortium responsible for monitoring variants of the coronavirus circulating in Argentina, explains that this is what has happened in other countries such as the United Kingdom, Ireland, Denmark, Switzerland, Israel and parts of the United States. States.

Spain. In Spain, for example, there is talk of a double pandemic. While cases with the original version of the virus are declining, an increase in infections with the UK variant is seen in 17 provinces.

In Catalonia, 85% of cases correspond to this variant and in Madrid, 60%. Experts believe that this resurgence could generate a fourth wave in this country.

Denmark. Denmark does a very detailed follow-up of the variants circulating in this country. The first infected with the British version was in December. By mid-January, they already represented more than 10% of cases.

From there, its impact accelerated and in two months it caused over 80% of cases, as shown in the following graph.

“If these variants advance, we will have a new pandemic which will be caused by a more contagious and deadly virus,” says Debat.

And he details that the 50-70% higher transmissibility of this version of Sars-Cov-2 involves a tragic exponential phenomenon. “It can generate five times more deaths than the virus that circulated in 2020,” he warns.

And remember that this is a variant that has a 65% chance of generating more severe cases.

Measures to stop them

Debat saves that the vaccines that are applied are effective against this variant. But he specifies that faced with a more contagious virus, a more vaccinated population is necessary to obtain collective immunity.

Roberto Etchenique, chemist and researcher at Conicet in Buenos Aires and testing expert, estimates that in mid-March 7.5% of cases in Amba were due to infection with the British variant. “In April, it will exceed 50% and its impact will start to be felt,” he says.

Right now, cases nationwide are increasing by 20% per week without the significant contribution of more contagious variants, he points out. And he adds, “When these variants dominate the scene in May, the growth rate could be 50 to 100 percent higher.”

These calculations take into account a scenario without restrictions on the movement of people to limit the circulation of the virus. For Etchenique, vaccination will not stop the progress of the pandemic because of these new variants. Experts believe that the only way to slow this progression is to strictly limit the movement of people.

“In view of the uncertainty, it is important to follow good practices and ensure that contagion is avoided,” says Debat.

And he adds: “It is essential to continue the efforts made in the epidemiological surveillance of all the variants.”

Arrival in Cordoba

In Cordoba, there are fears that the UK or Manaus variants are starting to circulate in the community. At present, the six cases detected in the Manaus version and the six in the UK were in people with a history of travel abroad and in close contact with them.

For more than a month, the Province analyzed 100% of positive cases from abroad. At the time, Cordoba’s health ministry announced that it would analyze mutations in 10 percent of positive samples processed by the province’s central laboratory, to monitor variants with community circulation.

To date, the Pais consortium has detected only one case of community traffic in Villa Dolores on the Rio de Janeiro bypass. Debat explains that it is not a worrying variant because it is not more transmissible. But one of its mutations is associated with an escape from the immune response.

“We need to be careful whether it starts to increase in frequency because of its implications in treatment with monoclonal antibodies and plasma. A priori, this would not affect the effectiveness of the vaccines, ”he explains.

This version of Sars-Cov-2 has been circulating in the community for over a month in Amba. The detection at Villa Dolores could be due to an irradiation of Amba throughout the country.

Could something similar happen with the UK or Manaus variant? Debat believes that progress is inexorable, but the scenario is too complex to predict when it can happen.