The coronavirus is crushing the biggest names in U.S. air travel.
In 2019 the nation's airlines carried an estimated 926 million passengers, a 43% increase from 2003.
But that demand hit a wall in March 2020 after U.S. carriers reported an enormous drop in bookings amid the spread of the coronavirus.
Airlines, at the center of the epidemic, have come under intense scrutiny over the safety and cleanliness of their cabins.
Health officials say air travel is causing viruses and bacteria to spread globally faster than ever before.
"Air travel does hasten the speed with which infectious disease spreads around the world," said professor Vicki Hertzberg, a biostatistician at Emory University and lead author of a separate study on how an infection can spread aboard an airplane.
Delta Air Lines is planning to reduce seat capacity by 70% and announced the carrier's second-quarter revenue would be $10 billion less than the same period the year prior.
To combat the pandemic, airlines have imposed new safety regulations and are using enhanced cleaning techniques inside their plane cabins.
In addition to its normal cleaning program, Delta is using a high-grade, EPA-registered disinfectant to wipe down common surface areas in galleys and lavatories. The airline has also added a "fogging process" used in many health-care facilities that pushes out an EPA-registered disinfectant on all trans-Pacific and trans-Atlantic inbound flights.
Starting Wednesday, all of Delta's domestic flights will undergo the same fogging process overnight and by early May, every plane in Delta's network will be fogged before every flight.
American Airlines and United Airlines said they are also using high-grade disinfectants and multipurpose cleaners on all touch points including window shades, armrests and tray tables. Aircraft that remain overnight at an airport receive an enhanced cleaning procedure.
United said that because of the coronavirus it will soon start using an electrostatic fogger to disinfect the air and surfaces within the cabin on all international arrivals into the U.S.
Watch this video to find out more about how airlines clean their planes.