So You're Going To A Place With Zika? Here's What You Need To Know

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Maybe it's a dive trip to Belize. Or a cruise in the Caribbean. Or maybe you've snagged tickets to the summer Olympics in Rio. If you're traveling in places where Zika is circulating, there are a few things you need to keep in mind — and bring along.

The first question is: Should you go on the trip at all?

If you're pregnant — or trying to get pregnant — stop reading now and consider canceling that trip, says Catherine Spong, the acting director of the National Institute of Child Health and Human Development. "Having Zika anytime during pregnancy is associated with risk for the fetus," she says.

And even if you're just thinking about getting pregnant in the next few months, you might want to reconsider a trip to Latin America, the Caribbean or the Pacific Islands. Yes, guys, I'm talking to you, too!

Why? Because after you return from a Zika-affected area, you should wait at least eight weeks before trying to conceive, the Centers for Disease Control and Prevention says — even if you felt fine the entire trip. About 80 percent of people who catch the mosquito-borne virus don't have any symptoms. They don't even know they got infected.

If men do show signs of Zika, like a rash or fever, they should wait six months before trying to conceive. The virus can linger in semen for several months, the CDC says.

Now, if you're not in the baby-making business anytime soon, traveling to Zika-affected areas is safe, the CDC says. You just need to take a few precautions to lower your risk of catching the virus:

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1. Put a helmet on that soldier. Zika can be transmitted sexually. So practice safe sex — or abstain — while traveling. "Use condoms correctly and consistently," the World Health Organization says, and continue to use them eight weeks after you get home.

2. Be sure there's running water and flushable toilets. Mosquitoes thrive in neighborhoods without running water or sewage systems, WHO says. These communities tend to have more standing water, where mosquitoes breed. So you're more likely to get bitten — and to get Zika.

These neighborhoods also tend to be overcrowded, which creates the perfect environment for Zika to spread, says Dr. Karin Nielsen, a pediatric infectious disease expert at UCLA. "You have to have clusters of people, who are sick, for mosquitoes to efficiently transmit Zika."

So it's best to avoid crowded, poor neighborhoods if you can.

3. The three "Ls" can keep mosquitoes away.

Long-lasting bug repellent: "Short-acting ones don't seem to work [for Zika-carrying mosquitoes]," Nielsen says.

DEET is the gold standard for long-acting sprays. A repellent with about 20 percent DEET will last five hours. And the CDC says it's safe for pregnant women.

"But doctors in Brazil are recommending the repellent picaridin for pregnant women," Nielsen says. "It lasts for about 10 hours. And it's less toxic than DEET."

Also, picaridin seems to keep mosquitoes at a greater distance than DEET, NPR reported earlier this year.

If you do go with DEET, stick to repellents with concentrations between 20 and 30 percent, the CDC says. Lower concentrations wear off more quickly. Higher concentrations can be toxic for children, the CDC says.

Long sleeves and pants: Mosquitoes love spaghetti straps and short shorts. The more skin you bare, the more bites you'll get.

And don't think that you're in the clear during the day. "The mosquitoes that spread Zika bite during the daytime, not around sunset or during the night," says Thomas Scott, an epidemiologist at the University of California, Davis.

So cover up those elbows, knees and toes, even during the day, he suggests.

Light-colored clothes: Mosquitoes that carry Zika — called Aedes aegypti — are attracted to black clothing, a scientist figured out back in 1938.

Red and violet look black to A. aegypti mosquitoes, so these colors also attract the insects, researchers wrote in a study published in 1966. "An increase in black-white interface in a checkerboard pattern [on clothing], or indeed any flicker effect, made an object yet more attractive to A. aegypti," the researchers added.

So when you're around mosquitoes, stick to clothes that are white, beige or yellow. Save the black and checkers for nighttime when A. aegypti mosquitoes aren't around.

4. Stay in places with screens or crank up the A/C.

A study published in March found window screens are the most effective way to reduce the risk of dengue — a virus similar to Zika that's also spread by A. aegypti. Screens reduced the risk of infection by 80 percent.

"Mosquitoes that carry Zika like to enter people's homes," says virologist Scott Weaver, at the University of Texas Medical Branch in Galveston. "So use screens or air conditioning. Otherwise, you have to protect yourself from mosquitoes even inside your home."

5. What to do when you return home.



Finally, after you get back to the States, be a good citizen. You could have an infection even if you don't feel sick. So if you live in a place with A. aegypti mosquitoes, keep up these precautions for a few weeks, Weaver says.

"Just a pay a little more attention to keeping mosquitoes out of your home or not encountering them outside," Weaver says. "That can go a long way to reducing the risk of triggering an outbreak here in the States." Or just passing the mosquito-borne virus to a friend or family member.