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As the world continues to struggle with the rapid spread of the omicron variant of the coronavirus and the still-lingering delta variant, scientists in France say they have discovered a new variant that contains multiple mutations.
Experts at the IHU Mediterranee Infection in Marseille said they had discovered the new variant in December in 12 patients living near Marseille, with the first patient testing positive after traveling to the central African nation of Cameroon.
The French scientists said they had identified 46 mutations in the new variant, dubbed B.1.640.2, that could make it more resistant to vaccines and more infectious than the original virus.
The results were posted on the online health sciences outlet MedRxiv, which publishes studies that have not been peer-reviewed or published in an academic journal. B.1.640.2 has neither been detected in other countries nor been labeled a "variant of concern" by the World Health Organization.
Meanwhile, a new study out of Denmark reveals omicron is better at avoiding the human immune system, even in people vaccinated against COVID-19. In a study of 12,000 households, researchers at the University of Copenhagen discovered that omicron was between 2.7 and 3.7 times more infectious than delta among vaccinated Danes.
The study, which has not been peer-reviewed, also found that unvaccinated individuals are more likely to transmit the coronavirus than those who have been fully vaccinated and received a booster shot. Against omicron, vaccine effectiveness was reduced to about 40% against symptoms and to 80% against severe disease, and booster shots improved those numbers to 86% against symptoms and 98% against severe disease.
"Our findings confirm that the rapid spread of the Omicron variant primarily can be ascribed to the immune evasiveness rather than an inherent increase in the basic transmissibility," the researchers wrote.
Omicron's spread
The omicron outbreak continues to wreak havoc on cities and countries around the world, pushing enormous strains on health care systems.
In the U.S., omicron represented 95.4% of the coronavirus strains in the country as of Saturday, according to the U.S. Centers for Disease Control and Prevention.
Omicron surpassed delta as the dominant strain since its initial detection in the U.S. on December 1, pushing daily infections past the 1 million mark on Monday, according to the Johns Hopkins Coronavirus Resource Center.
The numbers are nearly double that of the previous record of about 590,000 set just last week, driven mostly by the omicron variant.
The CDC said omicron accounted for about 77% of cases in the U.S. in the week ending December 25, a percentage sharply higher than its 58.6% projection announced the previous week.
Authorities in Australia's most populous state of New South Wales reported more than 23,000 new COVID-19 infections on Tuesday, breaking the previous record of 22,577 new cases set on New Year's Day, and 1,344 hospitalizations, surpassing the record of 1,268 hospitalizations back in September, at the height of the delta outbreak. Neighboring Victoria state posted 14,020 new cases Tuesday, breaking Monday's record of 8,577 new cases.
The states of Queensland and South Australia and the island of Tasmania also reported record numbers of new infections Tuesday, pushing Australia's total number of COVID-19 infections past the 500,000 milestone.
The surge has led to a critical shortage of staff members at hospitals across Australia, with health care workers furloughed after contracting the virus. Testing centers have also been forced to shut down either because of staffing shortages or testing backlogs. But Prime Minister Scott Morrison has rejected calls for the federal government in Canberra to provide free rapid antigen tests to all Australians.
Another Chinese city has entered into a full lockdown after three people tested positive for COVID-19 in recent days. Authorities have ordered all 1.2 million residents of the central city of Yuzhou to remain in their homes and have closed nearly all public facilities, including schools, transportation and shopping malls.
The strict lockdown measures in Yuzhou are similar to those imposed in the northwestern city of Xi'an, where 13 million residents have been confined to their homes since December 23 because of an outbreak of the delta variant that has sickened more than 1,600 residents. The lockdowns are part of Beijing's "zero-COVID" strategy that includes mass testing, lengthy quarantine periods and snap lockdowns.
Hong Kong leader Carrie Lam announced Tuesday that the semi-autonomous city is extending its vaccine requirements for public venues. Lam said that all Hong Kongers will have to show proof of vaccination to enter museums, public libraries and schools, effective February 24. The expanded vaccination mandate, which already covers entertainment venues, was imposed in the wake of Hong Kong confirming its first omicron infection cluster.
Some information for this report came from The Associated Press, Reuters and Agence France-Presse.