Do you remember SARS (Severe Acute Respiratory Syndrome)? It popped up in China in 2002 and spread to more than 25 countries before we could blink.
PKIDs landed a group of disease prevention educators in China just as the world became aware of this outbreak that would rapidly become an epidemic. It was coincidence, of course. The trip had been planned for months.
But, our proximity to the SARS outbreak was a reminder to us of how efficient air travel is at spreading germs.
In 2009, there were 2.5 billion airline passengers and that number is expected to increase to 3.3 billion by 2014. That’s a lot of sneezing, coughing, and just plain touching of armrests, overheads, and other surfaces going on in small spaces.
Dr. Alexandra Mangili and Dr. Mark Gendreau wrote a piece for the Lancet in 2005 that talks about the mechanics of disease transmission in an airplane. It’s very good, if you have a few minutes to read it.
They explain air flow patterns and how much air is recirculated (50% and that’s through filters). Turns out, air does not flow the length of the plane, but rather in sections or pockets along the width of the plane. Still an efficient method of disease transmission for airborne and large droplet transmission, but not the only way germs are spread onboard.
According to the article, the most common infections on aircraft have been via the fecal-oral route through contaminated food, although that has diminished in the last few years, possibly due to prepackaged food products and more care in the prepping and handling of food.
Mosquitos, a common vector for diseases such as dengue and malaria, often hitch rides on airplanes. Mangili and Gendreau point out that, “Many cases of malaria occurring in and around airports all over the world in people who had not travelled to endemic areas, known as airport malaria, is evidence that malaria-carrying mosquitoes can be imported on aircraft.”
The cabins of airplanes cannot be thoroughly disinfected between flights. Many times, a plane lands, passengers disembark, and more passengers are seated within 30 minutes. Think of all the droplets of goo left behind that the cleaning crew cannot remove, and the many surfaces that can’t be disinfected.
Keeping one’s hands clean throughout the flight will go a long way toward preventing transmission, and staying up-to-date on your vaccinations for your home country and your destination. As for masks, the authors say, “Although masks play a crucial part in infection control in health care settings, their use is unproven in disease control within the aircraft cabin.” But they do recommend masking and isolating someone suspected of having SARS.
The CDC has quite a bit more to say about air travel and travelers’ health in general, if you’re looking for more details.
How do you prevent infections during air travel? What do you do to protect yourself? We’d love to hear! Please share your tips in the comment section.
By Trish Parnell
Image courtesy of WHO