"I expect that we will surpass 10,000 cases per day by the end of the week, we will see the pressure on hospitals in the next two or three weeks," the South African epidemiologist said on Monday. Salim Abdool Karim, at a Ministry of Health online press conference.

Many uncertainties still hover over the dangerousness and transmissibility of the variant with multiple mutations.

But scientists are already worried that it is extremely contagious and eludes parts of the immune system.

South Africa has already seen a rapid increase in contamination in recent weeks: some 2,800 new cases were recorded on Sunday, against only 500 the previous week and 275 previously.

Hospital admissions have more than doubled in the past month in Gauteng, the most populous province comprising Pretoria and Johannesburg.

Almost three quarters of recently reported cases are due to the Omicron variant.

The proportion of positive tests increased from 2% to 9% in less than a week, even if these figures remain far behind the official figures of several European countries in particular.

"Even though Omicron is not clinically more dangerous and the first signals are not yet alarming, we will most likely see an increase in cases due to the speed of transmission," warned Mr. Abdool Karim.

Scientists believe, however, that the vaccines will remain effective against severe forms requiring hospitalization, he added.

"There is no need to panic. We have already been there," hammered the Minister of Health, Joe Phaahla, recalling that the country has already faced the Beta and Delta variants.

"In the next few days or weeks, our scientists will have the answers."

Vaccination in Pretoria, November 1, 2021 Phill Magakoe AFP

The announcement Thursday by scientists who detected the new variant in the southern African country caused a wave of panic, many countries such as France, the United States, Canada or the Philippines deciding in a few hours to '' ban travelers from southern Africa on their territory.

These chain reactions have sparked anger and outrage in South Africa.

South African President Cyril Ramaphosa demanded the "immediate and urgent lifting" of these restrictions, deeming them devoid of "scientific justification".

Closing the borders will not stop Omicron from spreading, repeated Mr. Abdool Karim.

This new form of Covid-19 presents "a very high risk" at the global level, warned the WHO.

The variant has already been detected in at least eleven other countries.

African country officially the most affected by the pandemic, South Africa has more than 2.9 million cases and nearly 89,800 deaths.

Only 23.8% of South Africans are fully vaccinated, more than elsewhere in Africa but far behind the rest of the world.

© 2021 AFP