Cuomo said the flu and COVID-19 will stress the state's testing capacity.
"You put the flu season on top of COVID," Cuomo said. "This is a very difficult situation to deal with, and that's going to be the second wave."
He says schools will be doing temperature checks on the way in, and they're looking for symptomatic children.
"First, they don't have to be symptomatic, they can be asymptomatic," the governor said. "And second, you're in flu season -- who doesn't have sniffles or a cough?"
He says the state is sending a letter to every county health department to ask how they are planning to conduct COVID-19 tests and flu tests simultaneously as labs have already deployed almost all of its testing capacity to COVID-19 testing.
"Now how do you do the flu test and the COVID tests at the same time," Cuomo wondered. "We have deployed almost all of our lab capacity to do COVID tests...It will require a reduction on the number of COVID tests or a reduction in the turnaround time on COVID tests. And we already have issues in the turnaround time on the number of COVID test."
Cuomo said he wants schools planning to reopen to take into consideration what's happening in other schools reopening throughout the county, including the University of North Carolina and Notre Dame, to make sure their schools doesn't end up in that situation, expressing that simply instructing students to practice to social distance will not work.
RELATED: How New York City and Tri-State area universities, colleges are reopening for fall 2020
"We've been telling young people to socially distance for the last six months," Cuomo said. "Go look at Manhattan on a Thursday night, Friday night, and on a Saturday night and tell me how well they've been listening. You think their behavior is going to change when they go back to school?"
In New York City, the United Federation of Teachers said on Wednesday that no schools in New York City should open unless they meet certain health criteria.
Teachers' union threatens legal action against NYC schools
"We are not going back to hell because of short-sighted political agendas," UFT President Michael Mulgrew said.
Meanwhile, the government's top infectious-disease expert Dr. Anthony Fauci said that reopening schools will look different in different parts of the country, though he urged areas with high rates of cases to "think twice" before reopening schools. He also said that reopening is not "all or nothing," that schools may have to "modify the things you do," such as wearing masks, having classes outside or having hybrid learning environments.
He criticized the federal coronavirus response saying that he would "like to see a consistent message for school reopening" from the federal government to guide the local authorities.
RELATED: New York Gov. Cuomo writing book on COVID-19 response
Fears grow as new COVID-19 hotspots emerge
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