The newly identified variants, which appear to be significantly more infectious than the strain that emerged in China in 2019, come as the growing number of viruses forces many nations to implement new blockades.
The committee meets normally every three months, but the WHO said the director-general pushed the meeting forward “to consider issues that need urgent discussion.”
“These are recent variants and considerations on usage [of] vaccination certificates and tests for international travel, “the world body said Wednesday.
Sars-CoV-2 mutations are causing concern among scientists working to find out if they will respond to vaccines.
In particular, a mutation, initially detected in South Africa and in later variants in Brazil and Japan, has caused alarm among researchers studying the variant, known as 501Y.V2, to determine whether current vaccines will be effective. .
Experts say vaccines are likely to work against the new variants. Studies to confirm are ongoing, but these experiments take time.
Cape Town University professor of infectious diseases Marc Mendelson told ABC News that it is not yet determined whether the South African variant is actually more contagious. “Studies to date suggest that people infected with this variant have an increased viral load, which will likely increase that person’s ability to transmit it to others. The evidence is backed by the rate of increase. of the number of infections during the second wave., in both South Africa and the United Kingdom, which has an independent variant that also carries the same mutation at position 501 of the ear protein, “Mendelson, who is also the head of the Division of Infectious Diseases and HIV Medicine in Groote, Cape Town. Schuur Hospital told ABC News.
Mendelson said urgent work is underway to study the mutation and hopes there will be answers in the coming weeks. “The most urgent question is whether mutations in the variant will affect vaccine responses. Then there is the question of whether the variant is associated with a more serious disease? I don’t see any evidence in the field (at my hospital), but the “Subtle differences need a lot of data to collect, so that’s anecdotal evidence. However, there is currently no sign of causing more serious illness.”
A preliminary study found that the Pfizer COVID-19 vaccine appears to work against the mutated virus, but more studies are needed because the South African variant has a number of additional mutations, including changes in some of the virus’s flagship proteins.
According to Mendelson, spike protein is not only vital for virus entry, but is also the target site for antibodies produced by humans to control viral infection. “Simply put, these antibodies neutralize the virus by binding to specific sequences of the ear protein, preventing it from binding to a receptor in our cells and thus preventing entry. If you can prevent the entry of the virus into the cells, you can prevent it from reproducing and The cause of concern is, once again, a series of mutations in the genetic code of the virus that has the variant.The resulting changes in the structure of the protein spike could reduce the binding of antibodies to their recognition, thus reducing the ability of our immune system to prevent the virus from entering cells and being caught. “
According to the WHO, the strain identified in South Africa has been found in 20 countries, territories and areas after it was first notified to the WHO on 18 December.
“Based on preliminary and ongoing research in South Africa, the 501Y.V2 variant may be more transmissible than those previously circulating in South Africa,” the agency’s weekly report said.
“Furthermore, while this new variant does not appear to cause more serious illnesses, the rapid increases observed in the number of cases have put health systems under pressure.” The geographical extent of both variants is likely to be underestimated, the WHO said.
Fears about increased transmissibility of the new variants are causing new blockages and additional measures to contain COVID-19.
However, the South African strain causes more concern due to an additional mutation that scientists have on the verge, a so-called E484K, which may make certain vaccines less effective.
The WHO also noted that a third new variant of the “worrying” coronavirus, which is found in Japan, needs further investigation.
“The more the SARS-CoV-2 virus spreads, the more opportunities it has to change. High levels of transmission mean we should expect more variants to appear,” the WHO said. SARS-CoV-2 is the virus that causes COVID-19 disease. Viruses constantly undergo minor changes as they spread from person to person.
More than 90 million COVID-19 infections have been reported worldwide since the cases first appeared in December 2019. The death toll from the pandemic is close to two million people.