In the course of the week that ended on Saturday, Omicron accounted for two.9 % of instances throughout the nation, up from 0.4 % within the earlier week, in accordance with company projections released on Tuesday.
In the region comprising New York, New Jersey, Puerto Rico and the U.S. Virgin Islands, the proportion of Omicron infections had already reached 13.1 %.
In a briefing on Tuesday with state and native well being officers and representatives of public well being labs throughout the nation, C.D.C. officers warned of two attainable eventualities. The primary was a tidal wave of infections, each Omicron and Delta, arriving as quickly as subsequent month, simply as influenza and different winter respiratory infections peak.
“The early signals say there are going to be waves coming,” mentioned Scott Becker, chief govt officer of the Affiliation of Public Well being Laboratories, who was on the decision.
“We are already expecting an uptick, just because we have seen a lot of respiratory viruses already this fall, including R.S.V., which was extensive,” he added.
Federal well being officers additionally proposed a second state of affairs through which a smaller surge in Omicron instances happens within the spring. It was unclear which forecast was extra doubtless.
Early evidence about the variant has only begun to emerge, and it stays unclear how typically infections with Omicron result in hospitalizations or deaths. The variant appears in a position to partially dodge the physique’s immune defenses, however scientists haven’t but decided to what diploma vaccination and prior an infection could safeguard people from extreme illness.
To trace variants, the C.D.C. makes use of a nationwide surveillance system that collects samples, in addition to genetic sequences generated by business laboratories, educational laboratories, and state and native public well being laboratories.
The U.S. system was comparatively gradual to choose up instances of the variant, maybe partly due to journey patterns or restrictive U.S. entrance guidelines. However the system can also be constrained by blind spots and delays.
Final week, the C.D.C. reported that of the 43 known infections detected in america within the first eight days of December, 34 of the sufferers, or 79 %, had been absolutely vaccinated after they first began displaying signs or examined optimistic. Solely a few third of the 43 folks had traveled internationally within the two weeks earlier than analysis, indicating some degree of neighborhood unfold of the variant.
The combat towards Omicron could require the federal authorities to replenish funding for the response, the secretary of well being and human companies, Xavier Becerra, advised on Tuesday. Mr. Becerra told reporters that about $10 billion was left of the $50 billion Congress had allotted for testing.
For public well being labs, as for hospitals, staffing could also be a problem, Mr. Becker mentioned.
“It’s the same staff who do molecular testing and genomic sequencing and flu surveillance,” he mentioned. “We’re stretched already, so we have to begin to think about alternative plans, temporary staffing, bringing in people who helped during surge events last year.”
“The lab community is tired,” Mr. Becker added. “The health care community is tired. ‘Gear up, we may have another surge,’ is a tough message to hear.”
Dr. Tedros Adhanom Ghebreyesus, the director basic of the World Well being Group, mentioned in a information briefing on Tuesday that “Omicron is spreading at a rate we have not seen with any previous variant.”
Dr. Tedros and senior W.H.O. officers cautioned towards underestimating the variant. “Even if Omicron causes less severe cases, the sheer number of cases could once again overwhelm unprepared health systems,” he mentioned.
In america, state and native well being officers urged People to take steps to forestall the unfold of Covid by getting vaccinated, getting booster photographs and sporting masks in public indoor settings. Households and buddies gathering for the vacations should get examined earlier than celebrating collectively, gathering exterior if attainable or, if not, in well-ventilated areas.
“As the Delta variant continues its rapid spread in the U.S., state and territorial health leaders are becoming increasingly concerned about emerging data from Europe and South Africa that indicate the Omicron variant may be even more transmissible,” mentioned Michael Fraser, chief govt officer of the Affiliation of State and Territorial Well being Officers.
“Hospital capacity is already at a breaking point in many states because of severe cases of Covid-19,” he added.