New US Covid-19 cases hit plateau after steep drops
New cases fell as much as 25% in the week ended February 7 and 23% in the week ended February 21, before plateauing last week

The United States reported a 3% decline in new cases of Covid-19 last week, a much smaller drop than in the previous six weeks, and health officials warned that progress against the global pandemic was stalling.
New cases fell as much as 25% in the week ended February 7 and 23% in the week ended February 21, before plateauing last week, according to a Reuters analysis of US state and county reports.
The country logged an average of over 68,000 new cases per day for the week ended February 28, with deaths averaging at 2,055 per day.
"I remain deeply concerned about a potential shift in the trajectory of the pandemic. The latest CDC data continue to suggest that recent declines in cases have leveled off at a very high number," said Dr. Rochelle Walensky, director of the US Centers for Disease Control and Prevention.
Walensky said she was alarmed by some local governments rolling back restrictions on masks and social distancing just as more infectious variants of the virus are spreading. "We stand to completely lose the hard-earned ground we have gained," she said.
Twenty-nine out of 50 states reported more new infections last week compared to the previous seven days, whereas only seven states in the prior week reported weekly increases, according to the Reuters analysis.
New York had the highest number of new cases per 100,000 residents last week, followed by New Jersey and South Carolina.
As of Sunday, 15% of the US population has received at least one dose of a vaccine and 7.5% has received two doses, according to the CDC. The country administered an average of 1.6 million shots per day last week.
Deaths linked to Covid-19 rose 5.5% in the week ended February 28 to 14,387. Cumulatively, over 513,000 people have died from the virus in the United States, or one in every 636 residents.
The average number of Covid-19 patients in US hospitals fell 15% to 52,000 last week, the lowest since early November, according to a Reuters tally.
Stick to two-shot strategy
The United States must stick to a two-dose strategy for the Pfizer-BioNTech and Moderna Covid-19 vaccines, top US infectious disease official Anthony Fauci told the Washington Post newspaper.
Fauci said that delaying a second dose to inoculate more Americans creates risks.
He warned that shifting to a single-dose strategy for the vaccines could leave people less protected, enable variants to spread and possibly boost skepticism among Americans already hesitant to get the shots.
"There's risks on either side," Fauci was quoted as saying by the Washington Post in a report published late on Monday.
"We're telling people (two shots) is what you should do … and then we say, 'Oops, we changed our mind'?" Fauci said. "I think that would be a messaging challenge, to say the least."
He added that he spoke with UK health officials on Monday who have opted to delay second doses to maximize giving more people shots more quickly. Fauci said that strategy would not make sense in the United States.
He said the science does not support delaying a second dose for those vaccines, citing research that a two-shot regimen creates enough protection to help fend off variants of the coronavirus that are more transmissible, whereas a single shot could leave Americans at risk from variants such as the one first detected in South Africa.
"You don't know how durable that protection is," he said.
Fauci said on Sunday he was encouraging Americans to accept any of the three available Covid-19 vaccines, including the newly approved Johnson & Johnson shot.
The US government authorized Johnson & Johnson's single-dose Covid-19 vaccine on Saturday, making it the third to be available in the country following the ones from Pfizer/BioNTech and Moderna that require two doses.
Covid-19 has claimed more than half a million lives in the United States, and states are clamoring for more doses to stem cases, hospitalizations and deaths.