In all, 28 states have seen a downward trend, including several that took steps toward reopening relatively early, like Georgia, South Carolina, Oklahoma and Colorado.
A notable exception is Texas, where case numbers are up between 20% and 30% since the state began lifting stay-home restrictions on May 1. Thursday was particularly grim as the Lone Star State recorded 58 new deaths -- the state's highest one-day increase in coronavirus fatalities since the pandemic began.
In all, seven states are still experiencing upward trends in case numbers, while numbers appear to be holding steady in 15 others.
As of early Friday, more than 1.4 million people in the US have been infected with the coronavirus, and more than 85,000 have died, according to Johns Hopkins.
President Donald Trump on Friday announced what he called "Operation Warp Speed" to develop a coronavirus vaccine.
Trump named Moncef Slaoui, former head of the vaccines division at GlaxoSmithKline, and Army Gen. Gustave Perna to lead the effort, which the president said aims to develop a vaccine before the end of the year.
"We think we are going to have a vaccine in the pretty near future," Trump said, "and if we do, we are going to really be a big step ahead."
Health experts have said that timeline is highly ambitious because of the lengthy process of researching and testing vaccine candidates.
Parts of New York state to lift restrictions
Meantime, state officials continue to lift stay-at-home restrictions.
Parts of New York state, long the epicenter of the US outbreak, are eligible to begin a phased reopening Friday, Gov. Andrew Cuomo said Thursday.
Five regions — Central New York, Finger Lakes, Mohawk Valley, North Country and Southern Tier — have met the seven criteria required to start phase one of the state's reopening plan. Some industries like construction and manufacturing will be allowed to resume. Retail will remain limited to curbside or in-store pickup.
Still, the governor urged caution, warning residents, "Phased reopening does not mean the problem has gone away."
Cuomo extended a stay-at-home order late Thursday for other regions until May 28, unless they meet the seven requirements, like 14-day declines in hospitalizations and death, hospital bed availability, testing capacity and contact tracing.
On Friday, Cuomo said beaches in his state would reopen by Memorial Day weekend, along with beaches in neighboring New Jersey, Connecticut and Delaware.
Each state will specific rules, but they'll be similar, Cuomo said.
In New York's case, beaches can't exceed 50% capacity. Picnic areas will be closed and social distancing enforced. Visitors must have masks and wear them when they cannot social distance.
Parts of Louisiana, Maryland, Virginia and Oregon are also set to start lifting some restrictions Friday. By Sunday, 48 states will have partially reopened.
Testing is still a concern
With the reopenings and eased social distancing restrictions, testing remains a major concern, with health experts warning the US is still lagging behind.
While not every person who tests positive will need treatment, testing ensures most of the cases are identified and traced, said Dr. Richard Besser, the former acting director of the Centers for Disease Control and Prevention.
"Every case that's out there could be the spark that starts another outbreak in your community that gets out of control," he said.
With the right measures, countries can suppress transmission and avoid bouncing back-and-forth between lockdown and lifting restrictions, said Maria Van Kerkhove, the technical lead for the Covid-19 response at the World Health Organization.
South Korea and Singapore have been successful in containing the virus because they have rapidly identified it, started contact tracing and combated opportunities for it to resurge, she added.
Experts have said coronavirus is likely to keep spreading for at least another 18 months to two years — until about 70% of the population has been infected.
With nearly all states easing social distancing, the nation has now shifted to harm reduction -- which focuses on ways to reduce the risk if it cannot be removed entirely, said Dr. Leana Wen, an ER physician and the former health commissioner for Baltimore.
"We had a strategy before. That strategy was we would reduce the number of infections and at the same time build up our capabilities to do testing, tracing, isolation," she said Thursday night during the CNN global town hall on coronavirus.
"We know that that's what's going to be effective, but we are reopening before those capabilities are in place. So in essence, we're saying it's too hard. We're not going to be able to get there. And so we're switching to a new phase. "
The new strategy includes ways to slow the spread of the virus such as social distancing, avoiding unnecessary gatherings, changing ventilation systems and increasing time outdoors, she said.
Trial starts on drugs once declared dangerous
With the number of deaths growing in the US, finding a vaccine and treatment for the virus remain a top priority.
The National Institutes of Health started a new trial for people with mild coronavirus cases that uses drugs the agency once declared as dangerous.
Both the NIH and the Food and Drug Administration have warned against the use of the malaria drug hydroxychloroquine combined with the antibiotic azithromycin, saying they should only be limited to clinical trials.
The FDA says the combination should not be used outside of a hospital setting because it causes heart rhythm problems. In addition, several trials have shown the combination does not help coronavirus patients.
But the NIH said it would enroll 2,000 people infected with coronavirus to try the drug combination at home. Study participants must have a fever, cough and/or shortness of breath, it said, adding that the first person enrolled in San Diego.
"Participants will be randomly assigned to receive short-term treatment with either hydroxychloroquine and azithromycin or matching placebos," it said. "People living with HIV and pregnant and breastfeeding women also are eligible to participate in the study."
The NIH did not respond to CNN's request for comment.
CDC sets up 'decision trees' on reopening
Places considering reopening their doors after weeks of restrictions are getting additional guidance from federal officials.
The six documents posted on its website Thursday provide step-by-step guidance advising employers to encourage social distancing, hand washing and intensified cleaning.
They do not provide any detailed advice on when it would be safe for schools or business to open -- only questions to ask before making any decisions.
Its purpose is to assist employers in making reopening decisions, but it's still important for them to check with state and local health officials to meet the unique needs and circumstances of the local community, the workplace tree reads.
They include small adjustments to account for the differences between schools, for instance, and restaurants.
MLB is making plans to play in the summer
Since the stay-at-home-orders to combat the spread of the virus, Major League Baseball has been losing money. Now it's working on plans for a modified season in which games would take place in empty stadiums, Commissioner Rob Manfred said.
"It's hopeful that we will have some Major League Baseball this summer," Manfred said at CNN's global town hall. "We are making plans about playing in empty stadiums. But as I've said before, all of those plans are dependent on what the public health situation is."
Manfred said he'd spoken to governors in 18 states where the game is played and most expressed hope they'd be able to use the empty parks this summer.
The economic fallout from the coronavirus pandemic could put MLB franchises in a $4 billion hole, he said.
Some states are taking steps toward allowing typical summer activities in the coming weeks.
Rhode Island Gov. Gina Raimondo announced Thursday her state had a goal of allowing summer and youth camps to operate in-person beginning June 29. Camps will be subject to strict hygiene and social distancing guidelines, such as keeping children in small groups of 10.
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