These are the two new variants of omicron that triple the cases of covid in South Africa

The number of positive cases of covid-19 in South Africa has grown strongly in the last two weeks due, according to experts, to two new variants of omicron recently discovered.

The BA.4 and BA.5 subvariants have tripled the daily cases of infection, which have gone from about 1,500 a day to more than 5,000, according to figures from the World Health Organization.

However, the South African scientists rule out that BA.4 and BA.5 are more contagious than omicron or that they are capable of overcoming the defenses of the vaccines, but instead relate the increase in infections to the loss of immunity with the passage of time. months.

“Given that the increase in infections occurs four months after the start of the omicron wave, it is plausible that decreased immunity is an important factor,” the authors write.

Where the new variants do seem to be more contagious is in people who have not been vaccinated, and who only have the natural defenses that their body created after contracting the first version of omicron, the so-called BA.1, explains Tulio de Oliveira, one of the report’s authors, in .

“That’s why a new wave is starting to break out in South Africa,” says the doctor. “What we’re seeing now, or at least the first indications, is not completely new variants emerging, but current variants starting to generate lineages of their own.”

The scientists show that the BA.4 and BA.5 variants have rapidly gained ground over previous lineages. If during the fourth wave of infections that the country suffered in December and January, BA.2 dominated, the new variants already account for more than 50% of the cases detected.

The authors of the report also point out that these two new variants emerged as a result of that fourth wave, between December and January, while BA.2 would have emerged between October and November.

They have already been found in the US.

The two branches BA.4 and BA.5 of the omicron variant have already been detected in the United States. According to the Gisaid covid-19 variant tracking service, in North America until last Friday, 12 cases of the BA.4 subvariant and five of the BA.5 had been sequenced, according to Fortune magazine.