The risk of reinfection with the omicron variant of the coronavirus is three times higher than with other strains such as beta or delta, but existing vaccines continue to protect against the most severe symptoms of COVID-19, according to a preliminary study by South African researchers published this Thursday.
Despite the fact that the scientific community insists that more time is needed to better understand the characteristics of omicron and its impact on the population, the data collected so far suggest that it has a "substantial capacity to evade the immunity of a previous infection" .
A man undergoes a diagnostic test for COVID-19 at a train station in Ahmedabad, India on December 3, 2021.Ajit Solanki / AP
"Against our expectations and experience with other variants,
we are now experiencing an increased risk of reinfection
that exceeds our previous experience," said Juliet Pulliam, co-author of the study, in a statement quoted by The Washington Post.
This would partially explain why this new variant has spread so rapidly through South Africa, plunging the country into its fourth wave of COVID-19 since the pandemic broke out, as Health Minister Joe Phaahla confirmed on Friday.
The South African researchers agree in any case that "
vaccines are the tool that can prevent the disease from being serious and requiring hospitalization,
" explained infectious disease specialist Richard Lessels, during the presentation of the progress of the omicron study of the Network of Surveillance of the Genome South Africa (NGS-SA, for its acronym in English) before the Health Commission of the Parliament of the country.
"A large part of the population is getting immunity from vaccines or passing the disease, so it is complex to say what the evolution will be. The genetics of the omicron is completely different from the delta or previous variants," said Lessels , according to the newspaper El País.
The World Health Organization (WHO) supports the preliminary conclusions of the South African researchers and is committed to acting with caution, but without falling into panic.
"The fact that
they are not getting sick means
that the vaccines continue to provide protection and we hope they continue to do so," said the institution's chief scientist, Soumya Swaminathan, in a briefing with Reuters.
WHO believes that air restrictions imposed on flights from South Africa and other countries in the region
can help buy time
until more information about the new strain is obtained, but insists that vaccination is the best mechanism to protect against its spread.
"We will fight this variant with science and speed," says Biden when announcing his winter plan.
Dec. 3, 202102: 07
The challenge researchers face in determining the effectiveness of omicron vaccines is that drug immunization levels in African populations
are very low
compared to those in the United States or Spain, with more than 70% and 89% of fully immunized adults.
Although the vaccines appear to offer great protection against serious illness or hospitalization, scientists have not been able to determine whether the omicron virus is more severe because the majority of infected people in South Africa and neighboring countries are young people under 40 years of age. with a stronger immune system than older people.
The omicron variant was located last week and has already been detected in almost thirty countries on all continents.
