At the peak of flu season several years ago, I flew to Sudan to join a team of archaeologists searching for an ancient Nubian temple thought to hold a pharaoh’s ransom in gold and artifacts. But within hours of reaching Khartoum, I had a wretchedly sore throat, a nagging cough, achy muscles, and a 102.5-degree fever. Colds develop more slowly, so it was no surprise when I was diagnosed with flu. I struggled out of bed five days later and managed to get to the dig, but by then the team had decided to halt the search until the following year. My Indiana Jones fantasy had been sabotaged—by something as preventable as the flu. Don’t let it derail your own plans.
1. Travel Smart
Upper respiratory infections are among the most common illnesses that affect international travelers, second only to stomach flu. (The two are unrelated.) Jet lag and the general stress of transit conspire to weaken your immune system. In the Northern Hemisphere, where flu season lasts from late October through March, the virus peaks during the holidays. Try limiting your trips then, and take vacations in spring instead. And as elementary as it sounds, washing your hands (or disinfecting them with alcohol-based sanitizer) is still the best way to prevent infection.
Next: Know Your Enemy
2. Know Your Enemy
Every year between 5 and 20 percent of the U.S. population comes down with seasonal influenza. You cannot acquire lifelong immunity, as you can with polio or measles, because flu viruses constantly mutate into new strains. Of those that infect humans, Type A is the most virulent. It kills 36,000 Americans a year and puts another 164,000 in the hospital. Type B is more benign but still brutal, while Type C is like a mild cold.
Producing a vaccine to combat such a variable pathogen is like hitting a moving target. Health officials confer almost a year in advance, near the height of each hemisphere’s flu season (February up north, September down south). The vaccine contains three inactivated viruses—two Type A strains and one Type B—that trigger your immune system to produce antibodies against those particular viruses. Based on the most common strains going around that year, officials estimate which are likely to hit hardest the following season and include those three in the vaccine. "It’s a roulette game," says David Taylor, M.D., chief medical officer of biotechnology company VaxInnate. Even so, "It’s still worthwhile to get a shot," says Carolyn Bridges, M.D., of the Centers for Disease Control, because it offers cross-protection and reduces the severity of individual cases.
Next: Get Vaccinated
3. Get Vaccinated
"There’s no good reason not to," says David Shlim, M.D., a travel-medicine specialist. "It’s an insurance policy." In healthy people under age 65, the vaccines are 70 to 90 percent effective in preventing flu, and the risk of severe reaction is just one in four million. If you hate needles, request FluMist, which is administered nasally.
The most promising development is a universal vaccine that would work against all flu viruses, including emerging strains capable of causing a pandemic. Whereas the current vaccine responds to highly mutable proteins on the virus’s outer surface, a universal vaccine would work by targeting internal proteins that remain constant over time and among strains, so it wouldn’t need to be updated annually. It would be a boon to travelers, combating viruses circulating in the Northern and Southern Hemispheres and in the tropics, where flu seems ever present. Plus, it would be available to U.S. consumers year-round rather than just during the winter flu season.
VaxInnate is developing a universal prototype that would be
produced through fermenting bacteria—instead of the current method of growing the virus in chicken eggs—so it could be made cheaply and rapidly in huge quantities, "like making beer," Taylor says. "The cost of delivery would be much higher than manufacturing it." Clinical trials for several universal vaccines, including VaxInnate’s, are being planned now. But even if one receives FDA approval, it’s not likely to replace the old standard until its safety and effectiveness are proven over time.
Ultimately, the best use of a universal vaccine may be in combination with the old, to provide broader protection in case the three strains selected for the yearly formula turn out not to be most prevalent. It may also prove useful as a one-time, stand-alone vaccine in developing countries that can’t afford annual inoculation programs.
Next: Prime Your Defenses