(CNN) As cases continue to rise, Americans looking to a vaccine as the way out of the coronavirus pandemic should consider a more comprehensive approach, a leading medical expert told CNN on Wednesday.
"Pinning all our hopes on a vaccine that works immediately is not the right strategy," Dr. William Haseltine, a former professor at Harvard University's medical and public health schools, told CNN's Wolf Blitzer.
Haseltine said a broad public health strategy is a better way to contain the spread of the virus along with the help of a vaccine and therapeutic drugs. Mandating masks will help but Haseltine said, "we need a lot more than masks to contain this epidemic that's running through our country like a freight train."
Haseltine recommended closing bars and other places where young people congregate at night and ban holding large meetings in the worst-hit regions. Life won't get better until people make major changes to their behavior and public health services come forward with more resources, he said.
He said a vaccine is still six months away at the earliest and he warned not to underestimate a coronavirus. Haseltine, known for his work on fighting cancer and HIV/AIDS, said it won't be easy to develop a vaccine.
"These are tricky viruses," he said. "It's not as simple as measles or mumps. It's going to be a lot more complicated"
Any Covid-19 vaccine that's sponsored by the US government will be free or affordable for the American public, Health and Human Services Secretary Alex Azar told CNBC on Wednesday.
"For any vaccine that we have bought -- so for instance the Pfizer vaccine -- those hundred million doses would actually be acquired by the US government, then given for free to Americans," Azar said.
He said the same would apply with the AstraZeneca and the Novovax vaccines.
"We will ensure that any vaccine that we're involved in sponsoring is either free to the American people or is affordable," Azar said.
More than 100,000 people have volunteered to participate in Covid-19 vaccine clinical trials, said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
"I think we'll be fine with regards to getting enough people," Fauci said during a webinar Wednesday with the TB Alliance.
The US is heading in the wrong direction with Covid-19 numbers, and it's doing so with astonishing speed.
Just after 1,000 people died in a single day, the country is about to reach 4 million Covid-19 cases.
To put that in perspective, the first reported case came on January 21. After 99 days, 1 million Americans became infected.
It took just 43 days after that to reach 2 million cases.
And 28 days later, on July 8, the US reached 3 million cases. The 4 millionth case could come just two weeks after that.
As of Wednesday night, more than 3.96 million people had been infected across the US, and more than 143,000 have died, according to data from Johns Hopkins University.
Some states are reporting record-breaking numbers of new cases. Johns Hopkins reported at least 68,706 new cases and 1,152 deaths in the US on Wednesday.
More governors are requiring masks, and dozens of hospitals are out of intensive care unit beds.
President Donald Trump said the United States has now conducted more than 50 million coronavirus tests. He told reporters at a White House briefing that people should wear masks, pay attention to social distancing and wash their hands. While hot spots like Florida and Texas have popped up, it's all going to work out, he said.
"We're all in this together," he said.
California, the most populous state and the first to shut down months ago, appeared to have Covid-19 under control -- only to suffer a massive resurgence and surpass New York with the most coronavirus cases in the nation.
This month, state Gov. Gavin Newsom shut down bars and indoor restaurant services again due to an influx of cases after reopening.
Covid-19 is set to become one of the leading causes of death in Los Angeles County, according to Barbara Ferrer, the county's health director.
"It's killing more people than Alzheimer's disease, other kinds of heart disease, stroke and COPD," Ferrer said, referring to chronic obstructive pulmonary disease, which causes airflow blockage and breathing issues.
Comparing Covid-19 to the flu, Ferrer said data shows Covid-19 killed twice as many people in six months as the flu did in eight months.
Some politicians, including the President, have insisted that much of the soaring case numbers are a reflection of increased testing.
A CNN analysis of testing data from the Covid Tracking Project reveals the positive test rate -- or the average number of positive test results out of 1,000 tests performed -- has increased significantly in many of the current hotspots, including Florida, Arizona, Texas and Georgia.
Florida saw an average rate of 35 positive results per 1,000 tests during the month of May. But in June, that number nearly tripled to 105. So far in July, the average rate of test positivity has been 187 out of 1,000.
But Florida Gov. Ron DeSantis said the state is on the "right course" in the fight against the virus.
"I think we will continue to see improvements," the governor said Tuesday. "We just have to, particularly Floridians, have to continue doing the basic things."
Over the weekend, nearly 50 Florida hospitals said they were out of ICU beds. Statewide, the ICU bed availability had dwindled to 15.98% on Tuesday, down from about 18.1% on Monday.
And new data from the CDC also show infections could be more than 10 times higher than the number of reported cases in some parts of the US.
Researchers estimate the US will have 219,864 total Covid-19 deaths by November 1, according to the Institute for Health Metrics at the University of Washington.
That's actually a decrease of about 5,000 deaths from the IHME's previous forecast of 224,546 by that date.
The reasons for the slightly better forecast include more face masks mandates, more people wearing masks, and more people practicing social distancing, the researchers said.
"So a mandate is very important and helping, and a national mandate, of course, would do much better," said Ali Mokdad, a professor of health metrics sciences at the IHME
If Americans wore masks nationwide, the number of total deaths by November 1 would drop to 185,887, the researchers project. But if the mandates ease more, the US could have 231,012 deaths by November 1.
At least 41 states have some kind of mask requirement in place or planned. Starting Saturday, Minnesota will require people to wear masks inside businesses or indoor public settings. People who have conditions that make "it unreasonable for the individual to maintain a face covering are exempt from the order," Gov. Tim Walz said.
Trump said Wednesday he would make a decision over the next day on whether to mandate masks on federal property.
With the high transmission levels of the virus, traditional contact tracing has now become "impractical and difficult to do," said California Health Secretary Dr. Mark Ghaly.
The state is working to refine strategies and continue to work with counties to build up their "tracing army," but Ghaly warns that "even a very robust contact tracing program will have a hard time reaching out to every single case."
Contact tracing is now harder all over the nation while testing results take days, Fauci said.
Quest Diagnostics, a leading commercial testing lab, said in a news release Monday that for some patients, testing results can take up to two weeks.
"The time frame from when you get a test to the time you get the results back is sometimes measured in a few days," Fauci said Tuesday.
"If that's the case, it kind of negates the purpose of the contract tracing because if you don't know if that person gets the results back at a period of time that's reasonable, 24 hours, 48 hours at the most ... that kind of really mitigates against getting a good tracing and a good isolation."