If you’re headed to the Olympic Games in Rio next month, rest assured that it’s highly unlikely you’ll return home afterward with the Zika virus.
A recent analysis by the U.S. Centers for Disease Control and Prevention compared the expected 350,000 to 500,000 Olympic spectators and participants to the number of total estimated travelers to Zika-affected countries during 2015. The results revealed that Olympic travel will make up just one-quarter of one percent of last year’s travel volume. This means the games don’t pose a serious risk of Zika transmission beyond normal travel patterns.
However, this doesn’t mean there is zero risk. Four countries in particular (Chad, Djibouti, Eritrea and Yemen) face a unique threat because the Olympic Games will significantly increase travel to and from their countries and a Zika-affected area. The truth is that anyone can be bitten by an infected mosquito if they don’t take proper precautions, like wearing repellent or long-sleeved clothing throughout their stay.
For people traveling to Brazil or any other Zika-affected country this year, it’s important to know the signs and symptoms of an infection, and how to get tested. Because diagnostic testing is a complex, limited resource that can only be performed by local and state laboratories, not everyone who wants a test can obtain one.
Here’s a simple flowchart, based on recommendations from the CDC and interviews with Zika virus experts, that explains whether or not you can request a Zika virus diagnostic test from your doctor. Because our knowledge of Zika virus grows every day, we will update this flowchart as needed to reflect the latest recommendations from the CDC. (Use this updated list of Zika-affected countries and territories to answer the first question below.)
Here are five things to know about getting a Zika virus test.
1. Pregnant women come first.
And by that, we mean pregnant women are the first priority when it comes to testing. The virus can have a devastating effect on a developing fetus, and pregnant women are most at risk if they contract what’s generally considered a very mild mosquito-borne virus.
Because of this, if you’re a pregnant woman who has either traveled to an area affected by Zika or been potentially exposed to the virus through unprotected sexual contact (oral, anal or vaginal sex, or the sharing of sex toys) with a partner who has recently traveled to a Zika-affected area, get tested for Zika virus. You can get tested even if both you and your partner are asymptomatic, but you should request a test immediately if either of you experience symptoms like fever, rash, joint pain and red eyes. These guidelines, recently updated by the CDC July 25, apply to both gay and straight couples.
“Before, we weren’t offering any testing for people with sexual exposure to an asymptomatic partner,” explained Dr. Neil Silverman, an obstetric infectious disease specialist at the University of California, Los Angeles. “Now those [pregnant] women should be tested, and the timing of exposure will determine which kind of testing is offered.”
Pregnant women who traveled to an affected area within eight weeks prior to conception can also request a test, said a spokesman for the California Department of Public Health.
This typically means the clinician will draw samples of blood, cerebrospinal fluid or amniotic fluid and send them off to a state laboratory. Urine can also be used to test for the presence of Zika virus.
The threat to pregnant women is so great that even women without symptoms can be tested more than 12 weeks after they return from a Zika-affected country or are potentially sexually exposed to the virus, the new guidelines state. And of course, standard prenatal care, which includes an ultrasound between 18 to 20 weeks, should be part of the care plan for pregnant travelers to check for signs of fetal infection.
2. People with Zika virus symptoms and a travel history should be on guard for all mosquito-borne diseases.
The symptoms of Zika virus might be so mild as to be negligible. But if you experience them, you should still visit your primary care physician and discuss your travel history, because the symptoms could be a sign of another disease that requires medical attention.
The Aedes aegypti mosquito can spread Zika, dengue, yellow fever and Chikungunya viruses to the people it bites, and these diseases all necessitate different levels of treatment and care. Just because you have a rash and a fever, that doesn’t mean you can assume it’s a “mild” Zika virus that doesn’t need medical attention.
“The fact that you have symptoms [after] coming back from an area where Zika has been transmitted doesn’t necessarily mean you have Zika,” said Silverman. “You could have dengue, which would be way worse.”
Dengue virus, also known as “break bone fever,” can progress to bleeding, organ failure and even death if left untreated. Death linked to Zika virus, meanwhile, is exceedingly rare, and the symptoms generally go away on their own with supportive care like rest, fluids and painkillers.
Pregnant women with male or female partners who live in or have traveled to a Zika-affected area should either abstain from sex or consistently and correctly use barrier methods throughout the pregnancy when having oral, anal and vaginal sex. Sex toys should also be sheathed to protect against infection, says the CDC.
3. Travelers with no Zika virus symptoms have no medical reason to request a test if they or their partners aren’t pregnant.
If you’ve recently traveled to a Zika-affected country and you’ve experienced no symptoms, there’s no medical reason for you to get tested if you or your partner are not pregnant. But can you request one anyway, just based on travel history alone?
Sorry, but no. While many people who get Zika virus will never experience symptoms, diagnostic tests are just too scarce a resource for someone to request one out of curiosity, or to see if they pose a risk to their sexual partner, said the CDPH. In fact, there is no such test.
“They’re really trying to limit the number of people who get tested because if you start testing a large, low-risk population, you’re going to increase your number of false positive results,” said Silverman. “And two, you’ll completely overwhelm an already somewhat overwhelmed state-based laboratory testing system.”
To be on the safe side, men and women who aren’t pregnant and aren’t showing any symptoms should still consider abstaining or using barrier methods to protect against sexual transmission of Zika virus for at least eight weeks after either partner has traveled from an area where Zika is spreading.
The timelines are slightly different for couples in which a partner has actually had Zika symptoms; men should wait for at least six months after onset of illness before considering unprotected sex, while women should wait at least eight weeks.
4. Stick to the waiting period if you’re trying to conceive.
Men and women who aren’t expecting but want to try conceiving after returning from a Zika-affected area should wait a certain amount of time, regardless of whether or not they exhibit symptoms.
Women should wait at least eight weeks after travel before trying to conceive. And if they experience Zika symptoms, they should wait at least eight weeks after the symptoms start before trying for a baby.
Men without symptoms should also wait at least eight weeks before trying to conceive, while those who have had symptoms should wait at least six months before trying.
5. Precautions don’t end once you return home.
Finally, no matter which category you fall into, all Olympic travelers or people who have come back from other Zika-affected areas should continue preventing mosquito bites for up to three weeks after they arrive back home to avoid spreading the disease amongst the local mosquitos ― even if they don’t experience any symptoms. This warning is especially important considering that mosquito season will be in full swing in the U.S. during the Olympics.
It’s also important to remember that we’re still learning a lot about how the virus is transmitted. The CDC confirmed July 18 that a caregiver for a man who traveled to a Zika-affected area and died after an infection with the virus also contracted the illness. This case is exceedingly rare, as the caregiver neither visited a Zika-affected area nor had sex with the person who traveled to the Zika-affected area. Utah also doesn’t harbor the kind of mosquitos that typically transmit the virus, which means researchers are still trying to figure out how the caregiver became ill in the first place.
“The new case in Utah is a surprise, showing that we still have more to learn about Zika,” said Dr. Erin Staples, a medical epidemiologist with the CDC in a statement. “Fortunately, the patient recovered quickly, and from what we have seen with more than 1,300 travel-associated cases of Zika in the continental United States and Hawaii, non-sexual spread from one person to another does not appear to be common.”
This story has been updated throughout to reflect the new CDC guidelines on Zika virus testing and transmission, released July 25.
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