As millions of Americans take to the skies and public transportation systems during the winter holidays, health officials are warning that crowded airports, airplanes, and transit hubs create prime conditions for the spread of respiratory illnesses and other travel-related health risks. The Transportation Security Administration expects passenger volumes during the holiday season to rival or exceed pre-pandemic levels, placing renewed focus on how travelers can protect their health while navigating busy travel corridors.

Winter holiday travel coincides with peak circulation of respiratory viruses, including influenza, COVID-19, and respiratory syncytial virus, according to the Centers for Disease Control and Prevention. These viruses spread most easily in enclosed, crowded spaces, particularly when people are in close contact for extended periods, as is common during flights, train rides, and airport delays. Surveillance data show that hospitalizations from respiratory illnesses tend to rise following major travel periods, reflecting increased exposure and transmission.

Airports and transit hubs present unique health challenges beyond viral exposure. Travelers often experience disrupted sleep, dehydration, and heightened stress, all of which can weaken the immune system and increase susceptibility to illness. Long security lines, delayed flights, and packed terminals can also make it difficult for individuals to distance themselves when feeling unwell, increasing the likelihood of exposure for others.

Public health experts emphasize that vaccination remains one of the most effective tools for reducing severe illness during travel. The CDC continues to recommend that eligible individuals stay up to date on flu and COVID-19 vaccines before traveling, particularly those at higher risk for complications, including older adults, people with chronic conditions, and pregnant individuals. RSV vaccination is also recommended for adults aged 60 and older, as well as for certain infants and young children. “Travel amplifies exposure,” said Dr. William Schaffner, an infectious disease specialist at Vanderbilt University Medical Center. “Being vaccinated before you get on a plane or train provides a critical layer of protection during periods of intense viral circulation.”

The design of modern aircraft offers some built-in protections, but risks remain. Airplanes use high-efficiency particulate air, or HEPA, filtration systems that can remove most airborne particles, including viruses, when operating properly. However, experts note that these systems are most effective once the plane is in flight, and passengers may still be exposed during boarding, deplaning, or while seated near someone who is actively ill. Mask use in crowded indoor travel settings, though no longer mandated, continues to be recommended by many public health authorities as a risk-reduction strategy during peak illness seasons.

Public transit systems, including buses and trains, pose similar challenges, particularly in urban areas where riders may rely on daily transit and have limited alternatives. Studies have shown that workers who depend on public transportation are more likely to be exposed to respiratory illnesses, highlighting the intersection between travel health and socioeconomic inequities. Communities of color are disproportionately represented among essential workers and transit-dependent populations, which contributes to higher exposure risks during winter surges.

Beyond infectious disease, winter travel increases the risk of physical injury. Slips and falls are common in icy parking lots, train platforms, and airport sidewalks, particularly among older adults. The CDC identifies falls as a leading cause of injury-related death among adults aged 65 and older, and winter weather conditions significantly heighten this risk. Carrying heavy luggage, rushing between terminals, and navigating unfamiliar environments further compound the danger.

Travelers are also advised to remain alert to symptoms before and during their trips. Public health guidance recommends postponing travel when experiencing fever, persistent cough, or other signs of acute illness, both to protect personal health and to reduce the risk of spreading infection to others. Rapid testing for COVID-19 prior to visiting high-risk relatives has become a common precaution, particularly for families gathering across generations.

Health equity considerations remain central to holiday travel health discussions. Access to paid sick leave, affordable testing, and preventive healthcare varies widely, influencing whether individuals feel able to delay travel when sick or seek timely care. Public health advocates stress that improving access to vaccines, clear health information, and workplace protections is essential to reducing travel-related illness disparities during the holidays.

As holiday travel reaches its seasonal peak, health officials emphasize that awareness and preparation can significantly reduce risk. By staying informed about circulating illnesses, taking preventive measures before and during travel, and recognizing when it is safest to delay a trip, travelers can help protect themselves and those around them. With crowded terminals and packed transit systems expected to continue throughout the season, experts say thoughtful travel decisions remain a key part of winter health protection.