© Grant Hindsley/AFP/Getty ImagesVirgina Mason advanced registered nurse practitioner Erin Forsythe loads a syringing with the Pfizer Covid-19 vaccine during a partnership with the hospital network and Amazon to increase the efficiency of vaccinations, at the Amazon Meeting Center in downtown Seattle, Washington on January 24, 2021. - Amazon is partnering with Virginia Mason for a one-day pop-up clinic on January 24. 2021 that aims to vaccinate 2,000 people at the companys Meeting Center near downtown Seattle. Virginia Mason is handling vaccine administration, while Amazon is providing the location and help with logistics. (Photo by Grant HINDSLEY / AFP) (Photo by GRANT HINDSLEY/AFP via Getty Images)
With the US now tallying more than 25 million Covid-19 cases, experts say now is the time to double down on safety measures and speed up vaccine rollouts before a variant further surges infections.
"The best way to prevent the emergence of new variants is to do all of the things we've been talking about for months," infectious disease expert Dr. Celine Gounder told CNN Sunday night. "The more you let the virus spread, the more it mutates, the more variants you'll have."
But the US continues to add staggering numbers of cases daily and faces several major challenges when it comes to vaccines. States say they don't have enough doses, and Centers for Disease Control and Prevention Director Dr. Rochelle Walensky said Sunday there's a lack of information on supply.
"I would say one of the biggest problems right now is I can't tell you how much vaccine we have," Walensky told Fox News. "If I can't tell it to you, then I can't tell it to the governors and I can't tell it to the state health officials."
"If they don't know how much vaccine they're getting, not just this week but next week and the week after, they can't plan."
It likely will be months from now until the vaccine is widely available to the American public, Gounder, who is also a former member of the Biden transition Covid-19 advisory board, said.
"We're looking at probably middle of the summer, end of the summer before the average, healthy, young American has access to vaccination," Gounder told CNN Sunday.
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US should boost its vaccination goal, expert says
But while the rollout has been slower than many experts hoped, the director of the National Institutes of Health says it is now not as bad as some are making it out to be.
"We are now averaging almost a million doses per day going into arms, and that's a pretty good trajectory to get to where President Biden wants to," Dr. Francis Collins told MSNBC Saturday.
Biden has previously promised to administer 100 million shots in his first 100 days in office -- a goal that has been criticized by some as too modest.
"We need to do better than a million shots per day," Dr. Jonathan Reiner, professor of medicine at George Washington University told CNN Sunday.
Most of the shots being administered currently are first doses, Reiner explained.
"But as we go forward, more and more shots every day will be the second vaccination so the number of new vaccinations is going to start to drop until we get to a point in the not too distant future where every day the shots that are given are 50% follow-up and 50% new vaccinations."
"We need to do better. We need to vaccinate about two million people a day. That should be the goal," Reiner added.
Agencies scaling up surveillance of variant
Meanwhile, Walensky also said Sunday the CDC and other agencies were scaling up both surveillance and studies of the new variants so that "we can monitor these variants as well as monitor" the impact they may have on vaccines.
The variant called B.1.1.7 -- first identified in the UK -- has already been detected in more than 20 states and, according to the CDC, is more easily transmissible. Dr. Anthony Fauci said it's possible it could also be more harmful.
"We need to assume now that what has been circulating dominantly in the UK does have a certain degree of increase in what we call virulence, namely the power of the virus to cause more damage including death," Fauci told CBS Sunday.
Studies so far suggest vaccines will protect against the B.1.1.7 variant. But at least two studies have found another variant -- first spotted in South Africa -- could pose a problem for vaccines.
That variant has so far not been detected in the US, but "we need to expand greatly our genomic surveillance," Fauci said.
"We know that it had not been at the level that we would have liked, but there's a lot of movement right now at the CDC level, including some input from the NIH and other organizations, to dramatically increase what we call genomic surveillance."
'We've got to be ready' for more virus changes
For many experts, the variants are concerning but not surprising.
The larger lesson to be learned is that the virus is going to continue changing -- and the US needs to be ready for that, Dr. Vivek Murthy, Biden's nominee for US Surgeon General, told ABC Sunday.
"We're in a race against these variants, the viruses interchange and it's up to us to adapt and to make sure that we're staying ahead," he said.
Murthy said this means there must be much better surveillance so that variants can be identified when they arise, that public health measures must be doubled down on and that there should be greater investment in treatment strategies.
"Above all, this means we've got to invest a lot more in testing and in contact tracing, because there also are going to be essential," Murthy added.