Two air passengers spread the mumps

Coffee, tea or contagion?

Over the past five weeks, the Midwest has experienced the nation's worst epidemic of mumps in almost 20 years. The first cases surfaced in Iowa, followed quickly by outbreaks in Illinois, Kansas, Minnesota, Missouri, Nebraska and Wisconsin. So far, nearly 1,000 people have been stricken, and at least nine required hospitalization.

Preliminary findings by the Centers for Disease Control and Prevention traced the source of infection to two airline passengers who may have separately infected dozens of people on nine flights between March 26 and April 2.

The first, a 51-year-old woman from Waterloo, Iowa, believes she may have contracted the virus during a visit in the Dominican Republic two weeks earlier. Because mumps can incubate for up to 14 days and be communicable for three days before symptoms appear, she may have infected passengers on five flights from Waterloo to Washington, D.C., as well as people she encountered in church and other gatherings. The second source may have been a young man who flew on four American Airlines flights returning to Cedar Rapids, Iowa, from a vacation in Tucson, Ariz.

Mumps is spread by coughing and sneezing, and its most common symptoms are fever, headache and swollen salivary glands under the jaw. It is easily treated but occasionally can lead to hearing loss, meningitis and swollen testicles, which can cause sterility. Childhood immunizations have greatly reduced the incidence of mumps in recent decades, but up to 20 percent of protected people can still get the disease.

This outbreak reconfirms how easily and quickly contagious illnesses can be spread in the close confines of trains, buses and airplane cabins.

Until recently, the recirculation of air during a flight was believed to be a factor, but tests have now clearly demonstrated that the High Efficiency Particulate Air (HEPA) filters in use on all commercial planes remove up to 99.9 percent of small bacteria and viruses (even SARS and bird flu virus).

More probable causes of contagion are coughing and sneezing of sick people. Moreover, the bottled airplane atmosphere can dry mucous membranes in the nose and throat, making them more susceptible to infection. The stresses of travel also may lower a person's resistance to disease.

In December, the CDC announced that it is working on a system to track air traveler information so that health officials can warn passengers of potential outbreaks of communicable diseases. This would include home addresses, emergency contact information and the names of travel companions. Creation of the database is at least two years away, but cash-strapped airlines may find it difficult to accommodate the additional information gathering and reporting.

Until then, health officials advise travelers first to be sure their own vaccinations are current. While traveling, be aware of any sick passengers around you. If you're seated near someone with a persistent cough or sneeze, you can ask to be moved, although that may not be possible on a full plane. Other alternatives: Cover your own face with a handkerchief or bandana; open your overhead vent to increase the flow of air at and away from your face; daub a bit of Vaseline or ChapStick in each nostril. Most important, be vigilant about washing your hands and face as frequently as possible, ideally with hot water and soap or antibacterial wipes.

If you're sick yourself, but can't postpone your trip, take handkerchiefs or tissues to use in transit or cough or sneeze into your sleeve. It's the least you can do.