You might think that recirculating air in the cabin would make you prone to getting sick, but commercial airlines actually have advanced filtering systems that remove most bacteria, fungi and viruses from the air. What's more likely to make you sick is close proximity with so many other humans and their germs.

Flying in an airplane can indeed make you sick, but it is rarely due to "recycled air" as many people believe. Modern aircraft in 2026 use High-Efficiency Particulate Air (HEPA) filters that refresh the cabin air every 2 to 3 minutes, removing 99.9% of bacteria and viruses. Instead, the primary cause of sickness is low humidity, which dries out the mucous membranes in your nose and throat, making them less effective at trapping germs. Additionally, the cabin environment is a "high-touch" zone where viruses can live on tray tables, armrests, and seatback pockets for hours. The pressure changes can also cause "ear barotrauma" or sinus pain, while the lack of movement on long-haul flights increases the risk of Deep Vein Thrombosis (DVT). To stay healthy, medical experts suggest staying hydrated, using a saline nasal spray, and frequently using hand sanitizer. For those prone to motion sickness, the inner ear's confusion between the perceived movement and the stationary cabin can trigger nausea, which is best managed by choosing a seat over the wing where the aircraft is most stable.