RT: Maria Van Kerkhove, Head of Emerging Diseases and Zoonoses at the World Health Organization (WHO), speaks at a press conference on the coronavirus situation at the United Nations in Geneva, Switzerland on January 29, 2020.
Denis Balibuz | Reuters
The World Health Organization expects the more transmissible version of Omicron to spread worldwide, although it is not yet clear if this subvariant can re-infect people who have become infected with an earlier version of the Omicron strain.
Maria Van Kerkhove, WHO technical lead on Covid-19, said on Tuesday that the global health agency is tracking four different versions of omicrons. Van Kerkhove said the BA.2 subvariant, which is more contagious than the currently dominant BA.1 version, is likely to become more common.
“BA.2 is more contagious than BA.1, so we expect BA.2 detection to increase globally,” Van Kerkhove said during a Q&A session streamed live on social media platforms on Tuesday. WHO.
WHO is monitoring BA.2 to see if the sub-option is causing an increase in new infections in countries that saw a rapid rise and then a sharp decline in omicron cases, Van Kerkhove said.
Van Kerkhove stressed that there is no evidence of a difference in the severity of infections caused by one or the other subvariant, although she noted that research is ongoing. Omicron does not usually cause alpha and delta disease in humans, although it spreads faster.
Researchers in Denmark have found that BA.2 is about 1.5 times more contagious than BA.1 and is better at infecting people who are vaccinated and even revaccinated. However, people who are fully vaccinated are less likely to spread it than those who are not vaccinated.
Van Kerkhove said vaccines are still very effective at preventing serious illness and death, although they do not prevent all infections. She urged people to get vaccinated and wear masks indoors.
Dr Abdi Mahamud, who’s Covid incident manager, said it’s not clear if BA.2 can reinfect people who previously had BA.1.
This can significantly affect the rate of spread of the virus. A UK study found that two-thirds of people who caught omicron said they had previously had Covid.
Most U.S. states have confirmed BA.2, although it is circulating at low levels, with 460 confirmed cases so far, according to an international database that tracks Covid variants.