Dr. Anthony Fauci said in a hearing that there are currently at least eight coronavirus vaccines in development, and the National Institutes of Health could learn as early as late fall if their trials is successful.
The NIH vaccine has been in development since January, and Fauci says that the development is "moving quickly."
Fauci said that having multiple vaccines in development could increase the chances of developing a successful cure, calling a "multiple shots on goal" situation.
Fauci also responded to questions regarding the Trump administration's plan to reopen the country. Fauci stressed that states be patient in following the plan.
"I get concerned if you're not seeing virus cases decline before a state opens up," Fauci said.
"If that occurs, you may trigger an outbreak that you cannot control," he said later.
Fauci said should states jump states, it would not only prompt "unnecessary death," but could send states backward in their path to economic recovery.
In an email to The New York Times, Fauci said that "reopening" the country amid the pandemic will result in "needless suffering and death."
"If we skip over the checkpoints in the guidelines to: 'Open America Again,' then we risk the danger of multiple outbreaks throughout the country," Fauci wrote, according to The Times. "This will not only result in needless suffering and death, but would actually set us back on our quest to return to normal."
CNN also reported that Fauci would issue such a warning.
While the number of new cases per day appears to have plateaued across the country, many health experts have urged political leaders to be cautious in lifting lockdown restrictions until the U.S. has increased its capacity to conduct COVID-19 tests.
The CDC reports that the U.S. is conducting between 25,000 and 30,000 tests a day. While President Donald Trump said on Monday that he hopes to increase U.S. testing capacity to 300,000 a day by the end of the week, many health experts, including Fauci, say even more tests will be needed to safely reopen the economy.
On Monday, the U.S. reached 80,000 deaths linked to the coronavirus pandemic. At least 1,900 people have died of COVID-19 each day since April 8. According to federal government estimates, about 1,500 people died in Hurricane Katrina in 2005.
Tuesday's hearing comes as states prepare to lift as states begin reopening their economies. As of Monday, more than half of states have begun reopening non-essential businesses.
Fauci, the director of the National Institute of Allergies and Infectious Diseases, is one of several health experts that will testify at Tuesday's Senate Health Committee hearing on Tuesday. CDC Director Dr. Robert Redfield and FDA Director Stephen Hahn are also expected to testify.
Fauci, Hahn and Redfield will all appear via video conference. They went into self-quarantine over the weekend after a White House staffer tested positive for COVID-19.