In talking about the measles outbreaks, experts always point out how contagious measles is.
A new report from the CDC, "Notes from the Field : Multiple Cases of Measles After Exposure During Air Travel --- Australia and New Zealand, January 2011," shows just how contagious.
Three unvaccinated children flew from Singapore to Brisbane, Australia (a 7 1/2-hour flight) and then after a 9 1/2-hour layover, continued on to Auckland, New Zealand on a 4-hour flight. Unfortunately, they developed a measles rash shortly after arriving in New Zealand, and so were contagious during these flights.
Three people on Brisbane flight and five people on the Auckland flight later developed measles.
Interestingly, only three of the eight cases of measles were in people that were seated within two rows of the original passengers with measles, which is usually the distance the health experts use to contact possible exposures to measles on a plane. However, since measles is so contagious, this report suggests that the area of exposure could be much further than two rows, in addition to the risk of exposure at the arrival and departure terminals and other areas of the airport.
Not surprisingly, in addition to the three unvaccinated children who started this outbreak, five of the secondary cases were unvaccinated, two had an unknown vaccinated status, and one had reportedly been vaccinated against measles twice.
This outbreak is a good example for how contagious measles can be, but also reinforces "the risk for exposure during international travel, which might start at the airport before departure, and the need for travelers to be protected against measles by vaccination."