The 7 On Your Side Investigates data team, along with ABC News, examined more than 20 million flight records from the tracking service Flightradar-24 and identified thousands of flights into the US and specifically the New York Metro area from cities in Asia and Europe just as coronavirus was overwhelming those foreign cities and making its way into the United States.
The flights carried hundreds of thousands of passengers who could have been carriers of COVID-19.
From December through March, airlines made more than 3,200 direct flights from China to the U.S.
One out of five of those flights landed in the New York area.
About 50 of those flights, originated in Wuhan, China; where COVID-19 was first identified. Nearly half of those flights from Wuhan landed at John F. Kennedy International Airport.
Other flights originating from other countries that have also struggled with the virus, such as Italy and Spain, also made regular stops in the New York area.
Our analysis indicates around 3,700 flights originated from Spain or Italy and traveled to the U.S.
Roughly three out of five of the flights from Italy landed in the New York area and roughly two out of five flights from Spain also landed in one of the three major New York-area airports.
Attending Emergency Physician Dr. Jijoe Joseph said many of the passengers were likely asymptomatic and unaware they were already infected with the virus.
He compared what happened at New York area airports to a freeway interchange at rush hour.
"These people became vehicles for this virus and if you think about the itinerary of travel, there are limitless options for reaching that final destination. This affects the masses. All of this becomes a vehicle for spreading the virus on an exponential level and it happened so quickly," Dr. Joseph said.
In February and March, the U.S. imposed several international travel restrictions but by that time, coronavirus had already gotten a foothold on the country.
It's why for now, doctors say limiting travel and limiting contact is so important until the virus dies out.
"I think if people were to shelter in place, we would see a flattening of the curve. This is science this is pure mathematics," Dr. Joseph said while expressing concerns that stay home orders have been loosely followed and unevenly enforced across the country.
This analysis of flight data excluded more than 1,000 routes by cargo haulers and hundreds of additional flights into Alaska, where we could not be determined with certainty whether the flights - mostly from China - carried cargo, passengers or both.
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