The rapidly spreading COVID-19 omicron variant has dominated the highly contagious Delta strain across much of the US, from less than 13% of cases sequenced on December 11 to more than 73% in a week’s time , the Centers for Disease Control and Prevention reported Monday.
It was unclear how fast Omicron has spread in California — the California Department of Public Health did not update its variant tracking data and did not immediately comment on Monday. But the rapid spread to the rest of the country worried infectious disease experts.
“Wonderful — it’s faster than I expected,” said Dr. Emeritus, clinical professor of infectious diseases and vaccinology at the UC Berkeley School of Public Health. John Swartzberg said. “I think it’s fair to say: It’s explosive.”
In the Bay Area, where the first US Omicron type case was reported on December 1 in a vaccinated San Francisco resident who had recently returned from South Africa, it was followed by six cases in Alameda County two days later and Santa Clara in one week. A case was registered in the county. Afterwards, health officials are bracing for a surge of infections and urging residents to get booster shots.
Contra Costa County reported its first cases of the variant on Monday — three residents, two of whom were fully vaccinated, though none had yet received a booster shot. No one has been admitted to the hospital yet.
“We knew it was still a while before the Omicron version arrived in Contra Costa County,” County Health Officer Dr. Chris Farnitano said in a statement. “We are encouraging anyone eligible to receive a booster dose of Pfizer or Moderna Vaccine to do so. With today’s news and the holidays approaching, this message becomes even more important. People who get a booster are much less likely to become seriously ill or be hospitalized. That’s our wish for this holiday season. ,
Omkron’s rapid spread in South Africa last month alarmed health officials around the world, leading the World Health Organization to declare Omkron “a type of concern” on 26 November. On Monday, the Director-General of the WHO urged people to cancel holiday celebrations for its slow pace. spread.
“There is now consistent evidence that Omicron is spreading much faster than the delta version,” said director general Tedros Adhanom Ghebreyesus. “There is no doubt that in many countries, increased social interaction during the holiday period will lead to an increase in cases, a collapse of the health system and more deaths. … it’s better to cancel now and celebrate later than to celebrate now and mourn later.”
CDC Director Dr. Rochelle Valensky said on December 14 that the Omicron version was “at about 3% nationwide” and “growing rapidly”, gaining ground on the highly permeable Delta variant that has been in effect since June and has been rolling out nationwide. The outbreak has increased. in the summer and fall The agency has revised upwards its numbers for the week to 12.6% from December 11. The variant has developed most rapidly in New York and other East Coast states, the Midwest, Great Lakes, and Northwest regions.
CDC data shows the Omicron variant spread in 0.7% of US cases by December 4 to 12.6% by December 11 and 73.2% by December 18. It took Delta more than a month to reach that level of dominance across the country.
In California, data from the Department of Public Health shows that the Delta version began to gain ground in April. Two months later Delta had accounted for less than half of the sequenced samples. But just a month after that, in July, Delta had 93% of cases, up from 99.5% the previous month. As of December 15, Delta had 98.6% and Omicron, of the 49 total cases, 1.4% of the samples sequenced in the state.
Swartzberg said that the Omicron is proving to be about five times more transmissible than the delta variant, which was more transmissible than the earlier variant, and that it is “hard to imagine” that its trajectory in California will be nationalized. Its not going to equate to rapid growth.
Health experts across the country urged people to get a vaccine booster shot to boost their immunity. The CDC earlier this month authorized booster shots for everyone 16 years of age and older.
Dr Ashish K Jha, dean of the Brown University School of Public Health, said on Twitter on Monday that “Omicron is now essentially everywhere.”
“It has taken over so fast,” Jha said. “You get the booster. Wear a mask to big indoor events. Use a rapid test before you assemble. We can get through this, people.”
Much is still unknown as to how toxic the Omicron variant will prove to be, with some data and reports suggesting mild illness and short-term spikes in infections.
Dr George Rutherford, an infectious disease specialist at the University of California-San Francisco, said figures from the United Kingdom suggest relatively low hospitalizations and omicron deaths. If the new version does cause minor illness, it would be a blessing to see it go beyond the deadly Delta version, he said.
Rutherford also noted that data from overseas suggests a small, sharp increase in cases before the crash of the Omicron infection wave, which would also be a pity.
Swartzberg said a recent study from Hong Kong indicates that while Omicron infects the upper respiratory system more readily, it is less active in the lower respiratory tract, where more severe disease is likely to occur. .
“An upper respiratory disease is a cold — we can live with that,” Swartzberg said. But he said a recent study from Imperial College London “faced the flies” that found the Omicron to be no less dangerous than the delta. “So we’ll have to wait and see about that.”