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The World Health Organization said on Friday that Covid omicron variants have been detected in 38 countries, compared with 23 two days ago. Early data suggests that the strain is more infectious than delta.
Maria Van Kerkhove, WHO’s head of Covid-19 technology, said in a live Q&A on the organization’s social media channels on Friday: “We do see an increase in growth rate, and we find that the number of omicrons detected is increasing. “But we have reports on omicron in 38 countries in all six WHO regions.”
Van Kerkhove said: “There is a saying that the spread has increased. What we need to know is whether its spreading capacity is more or less compared with the delta.” He pointed out that the delta variant still dominates the world.
Dr. Mike Ryan, Executive Director of the WHO Health Emergencies Programme, said, “It is clear that the virus does seem to be spreading effectively.”
“We saw this on delta before. Again, there are some things we shouldn’t be surprised by,” Ryan said.
Omicron has about 30 mutations in the spike protein, which is the mechanism used to bind to human cells. According to the World Health Organization, some of these mutations are related to higher transmission rates and the ability to evade immune protection.
South African scientists discovered this week that compared with past variants of the virus, omicron has the “powerful ability” to reinfect people who have already been infected with Covid. The study published by the South African Epidemiological Modeling and Analysis Center and the National Institute of Infectious Diseases has not yet been peer-reviewed.
Van Kerkhove stated that it is too early to understand the severity of the disease caused by omicron. She said that in some of the first cases, the mild symptoms reported earlier were based on a group of college students who tended to be younger and milder than the elderly.
“Initially there were reports that it tends to be more gentle, but it’s really too early now,” Van Khoff said. “Every person infected with SARS-CoV-2, regardless of the variant, always starts with a mild disease. So maybe it will stop in mild cases. Of course, some people have no symptoms, but it may be caused by mild disease. It may stop due to illness, or it may take some time.”
Van Kerkove said that the number of hospitalizations in South Africa is increasing, but public health officials have not seen an increase in the risk of death, but they are waiting for more data.
Ryan said that public health officials also initially saw mild cases of alpha and delta variants. If the mutation does cause more serious disease, it may take two weeks to see an increase in omicron-related mortality.
“Unfortunately, it takes time,” Ryan said. “We have also seen this in previous pandemic waves. When the incidence rate rises, it will take a week or two to cause hospitalization and death.”
Van Kerkhove warned that there is currently a reporting bias, which may obscure the true virulence of the variant. Many people around the world who have tested positive for omicron are healthy travelers, which may explain why the symptoms reported so far are mild.
“If you are traveling, you are not sick, or if you are sick you should not travel,” Van Khoff said. “Therefore, there is a bias in terms of what has been detected so far, but this will change over time.”
The first person in the United States to test positive for omicron was a fully vaccinated traveler, aged between 18 and 49, who returned to the San Francisco area from South Africa.
Van Kerkhove called on countries around the world to increase the genetic sequencing of Covid-19 cases to detect new mutations and publicly share the results to better understand the evolution of the virus.
“It’s time to strengthen the system,” she said. “It’s been a while since you heard us say this, but it’s not too late to do so-the system needs to be strengthened.”
Van Kerkhove pointed out that South Africa was the first country to report omicron to WHO, but as more countries start to sort the backlog of Covid cases starting in November, the timetable may change.
“Therefore, some of the earliest cases of this particular variant are probably not in South Africa,” she said.
Van Kerkhove and Ryan said that the current vaccine is still the most effective measure to slow the spread of the virus. Ryan said that there is a “clear relationship” between vaccine unfairness and the development of variants around the world. The WHO has repeatedly criticized rich countries for not doing enough to provide vaccines to people in poorer countries.
“There is no need to change the vaccine we currently use,” Ryan said. “There is no evidence to support this. There is no evidence to change, but if we want to change, how will we change these vaccines, and we need to complete this work ahead of time, there is still a lot of work to be studied.”