The traveler should start out with eyes open and then close them as symptoms improve. Air Travel Preventing Respiratory Problems and Dehydration . A flight cabin has very low humidity, so it's important to drink plenty of liquids. Of greater concern are studies suggesting that long flights combined with the confined space of an airplane and the close proximity to co-passengers from the entire world may facilitate the spread of contagious diseases, including tuberculosis. Sewage held in airplanes is a major cause of virus transmission and one study has found that current disinfectant treatments may be inadequate to eradicate all organisms.
Some countries spray the interior of planes with insecticides.
The World Health Organization has ruled this procedure to be safe, although it can cause an allergic reaction in some people and may be harmful for people with asthma and other respiratory problems. Some people have reported headaches, fatigue, nausea, and memory loss from the spray. Countries that may spray include those in Latin American, the Caribbean, Australia, and the South Pacific. Preventing Jet Lag . Crossing time zones can throw off the body's natural rhythms, especially when travelers fly from west to east.