The director of the National Institute of Health is testifying with other national health officials in a Senate hearing on how to reopen the economy.
More COVID-19 infections are inevitable as people again start gathering, but how prepared communities are to stamp out those sparks will determine how bad the rebound is, Fauci told the Senate Health, Labor and Pensions Committee.
"There is no doubt, even under the best of circumstances, when you pull back on mitigation you will see some cases appear," Fauci said.
And if there is a rush to reopen without following guidelines, "my concern is we will start to see little spikes that might turn into outbreaks," he said. "The consequences could be really serious."
In fact, he said opening too soon "could turn the clock back," and that not only would cause "some suffering and death that could be avoided, but could even set you back on the road to try to get economic recovery."
Fauci also testified that 8 candidate vaccines are now in clinical development, and we could know by late fall or early winter if successful.
He also warned that effective treatments or a vaccine would not be ready by the time school resumes in the fall.
Besides Fauci, of the National Institutes of Health, the other experts include FDA Commissioner Dr. Stephen Hahn and Dr. Robert Redfield, head of the Centers for Disease Control and Prevention - both in self-quarantine - and Adm. Brett Giroir, the coronavirus "testing czar" at the Department of Health and Human Services.
Redfield told the committee that the CDC is developing a surveillance program to ramp up "surveillance of asymptomatic infections" of COVID-19, which is "an important public health tool for early case identification."
Sen. Lamar Alexander, R-Tenn, chairman of the committee, said as the hearing opened that "what our country has done so far in testing is impressive, but not nearly enough."
Worldwide, the virus has infected nearly 4.2 million people and killed over 287,000 - more than 80,000 in U.S. alone. Asked if the U.S. mortality count was correct, Fauci said, "the number is likely higher. I don't know exactly what percent higher but almost certainly it's higher."
Fauci, a member of the coronavirus task force charged with shaping the response to COVID-19, testified via video conference after self-quarantining as a White House staffer tested positive for the virus. With the U.S. economy in free-fall and more than 30 million people unemployed, Trump has been pressuring states to reopen.
New York state is preparing to partially reopen later this week.
Three upstate regions - the Fingerlakes, the Southern Tier and Mohawk Valley, have met CDC guidelines and will start a slow reopening this Friday.
New York City, Long Island and our Northern Suburbs will have to wait.
"The likelihood, right now, unless something miraculous happens, we're going into June. So, I think it's fair to say that June is when we're potentially going to be able to make some real changes if we can continue our progress," Mayor Bill de Blasio said.
New York City still needs to see a 14-day decline in cases, a 30 percent hospital vacancy (right now it's at 29 percent) and more testing and contact tracing.
Before opening, they want to be able to quickly identify any new infections so those people can be isolated.
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