WASHINGTON — The coronavirus epidemic has many Americans reconsidering their plans, ahead of a popular travel time for spring break, to avoid outbreak areas or airports.

Airline industry analysts estimate the coronavirus will reduce the number of airline passengers by 4.7 to 6 percent worldwide, said Joel Szabat, acting Under Secretary for Policy at the U.S. Department of Transportation.

The U.S. has posted travel advisories warning Americans not to visit several countries, including China, and is now screening passengers flying to the U.S. from countries where the outbreak is present. No passenger screening is occurring at Bradley International Airport in Windsor Locks.

Passengers arriving at airports with symptoms of coronavirus, including fever, cough or difficulty breathing, receive medical screenings from officials from the Center for Disease Control and Prevention (CDC) and its contractors. The CDC is conducting screening at 20 airports across the U.S. for the coronavirus.

U.S. Customs and Border Protection may refer additional passengers who travel through affected areas for screening at their discretion. But at the moment, most airline passengers landing in the Connecticut area — such as at Bradley International Airport or Westchester County Airport — will not be screened.

“Since Bradley International Airport does not receive direct flights from the impacted regions, health officials have not called for any additional screening measures at the airport at this time,” said Ryan Tenney, public information officer for the Connecticut Airport Authority, which operates Bradley International Airport.

The airport’s only international nonstop flights are to Ireland, Canada and Mexico. Domestically, it has nonstop flights to Georgia, Maryland, North Carolina, Illinois, Ohio, Texas, Colorado, Michigan, Florida, California, Minnesota, South Carolina, Pennsylvania, Missouri, Puerto Rico and Washington, D.C. Coronavirus cases have been identified in some some of those countries and states.

Nationally, over 53,000 incoming passengers have received health screenings to date, Szabat said.

President Donald Trump on Wednesday met with the chief executives of seven airlines at the White House, along with members of his coronavirus task force.

"We believe, as the president said today, it’s safe to fly,” said Vice President Mike Pence, who also participated in the meeting on Wednesday.

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Some airlines have adjusted their policies for flight cancellations and change fees in response to the virus, COVID-19. Others say they are enhancing airplane cleaning and changing procedures to keep passengers and flight crews healthy.

But lawmakers said this week more action should be taken to ensure air travel is not a vector for spreading the virus further.

Members of Congress pressed top U.S. transportation and health officials for information about air travel and the coronavirus in a hearing Wednesday afternoon. They asked the officials about developing a mobile app to collect more information from passengers to trace the spread of the virus, waiving airline cancellation fees industry-wide and pressed the authorities to create guidelines on how airplanes can be sanitized to remove the virus.

Cancellation policies

During the Wednesday hearing, Sen. Ed Markey, D-Mass., pushed the U.S. Department of Transportation, which regulates airlines' consumer protection efforts, to end all cancellation and change fees across the airline industry during the coronavirus outbreak, calling them “beyond unfair."

Szabat said the DOT would consider such a measure right away.

Sen. Richard Blumenthal, D-Conn., also urged seven major U.S. airlines on Tuesday to waive all flight change and cancellation fees for travelers if they choose to change their plans due to coronavirus.

Last week, JetBlue Airways and Alaska Airlines made changes to their policies by waiving fees for customers changing or canceling flights purchased after Feb. 27. On Sunday, American Airlines announced a similar policy change, but with a restriction that customers need to make changes to their travel arrangements at least two weeks before departure to avoid the fees, and only for flight tickets purchased after March.

Blumenthal sent letters to American Airlines, Alaska Airlines, Spirit Airlines, United Airlines, Delta Air Lines, Frontier Airlines, and JetBlue Airways asking the companies to waive change and cancellation fees for an extended period as the outbreak continues.

"In considering the dangers and risks of travel, Americans should not have to face the additional burden of flight cancellation or change fees," Blumenthal wrote.

Travel advisories

The U.S. has travel advisories recommending Americans do not travel to China, South Korea, Italy, Japan and Iran. The Trump administration is considering further advisories as the outbreak spreads.

There are no travel advisories regarding air travel within the U.S.

“We re-evaluate this literally every single day," said Tony Fauci, director of the National Institute of Allergy and Infectious Diseases.

For State Department recommendations on air travel, visit travel.state.gov. or cdc.gov/coronavirus/2019-ncov/travelers/

Airline passengers traveling to the U.S. from places where there are coronavirus outbreaks are screened upon entry to the U.S. and, in some cases, before departing those countries.

“We are doing checks not only at the site of takeoff but the site of landing,” Trump said.

Passengers from China and Iran, where outbreaks are widespread, are funneled to 11 airports with enhanced coronavirus screening procedures and the ability to quarantine travelers. Those airports include John F. Kennedy Airport in New York and Newark Liberty International Airport in New Jersey.

Additionally, all airports in Italy and South Korea have begun screening passengers boarding direct flights to the United States. Those passengers have their temperatures taken and other screening measures.

Contact tracing airline passengers

Sen. Kyrsten Sinema, D-Ariz., pressed representatives from U.S. Department of Transportation, Centers for Disease Control and customs and border agencies to develop a mobile app to collect passenger travel information so federal health officials can contact people who have flown on a plane with an individual who develops a confirmed case of coronavirus.

In the hearing Wednesday, Szabat said the federal government's system for contact tracing — identifying who has been in contact with an infected person and getting in touch with them — is functioning at nearly 96 percent. But multiple officials noted that contact tracing has been a struggle for airlines, transportation, customs and health officials due to information-sharing procedures and technology challenges.

“It is paperwork and personnel intensive,” Szabat said. “We could not scale it up to be more broad.”

Stephen Redd, director of the CDC's Office of Public Health Preparedness and Response, said the passenger information U.S. officials receive is often incomplete.

“It’s a work in progress about having contact information,” Pence said Wednesday.

Officials said contact tracing for coronavirus was previously at 20 to 25 percent.

Cleaning planes and airports

In a White House meeting with Trump, multiple airline CEOs said Wednesday they are increasing efforts to make sure planes are clean.

Gary Kelly, CEO of Southwest Airlines, said his company has stepped up efforts to disinfect airliners. Bradley Tilden, CEO of Alaska Airlines, said his airline has changed cleaning and boarding procedures due to coronavirus.

Redd, from the CDC, said the virus can remain “hours to a whole day” on surfaces. The CDC will issue further health guidance for airplanes soon.

Bradley Airport said it is implementing advice from the CDC and state health officials to take health precautions and adjust operations as needed.

“We have increased our cleaning and sanitizing efforts, particularly in all of our high traffic and high touch point areas,” Tenney said.

Will travel measures protect us?

Trump has touted his quick action on implementing travel bans as key to slowing the spread of the virus in the U.S. But as the epidemic spreads across more states and countries will travel measures like bans and screenings remain important to coronavirus containment?

Leslie Dach, a former U.S. Department of Health and Human Services official who helped coordinate the Obama administration’s Ebola response, said no.

“It’s going to be much more difficult to do the screenings at the airports that you would need as the virus continues to spread,” Dach said. “People are coming from too many place. Folks are mingling in the community untested and we cannot rely on the travel measures to protect us. So the real question is what are we going to do here in the homeland to protect us?”

emilie.munson@hearstdc.com; Twitter: @emiliemunson