One traveled to Venezuela. One didn’t. Both now have Zika, and Dallas County health officials say the case almost certainly constitutes sexual transmission.
The case didn’t surprise scientists but it’s got people talking, and asking questions.
Does sexual transmission happen a lot?
Until Tuesday’s case in Dallas, only one case of certain sexual transmission of Zika had ever been documented: a researcher who came home from Africa to Colorado and infected his wife in 2008. But scientists knew it was theoretically possible.
Of course, most people who have sex live in the same place, so it would be almost impossible to tell whether someone was infected by a sex partner or by the same mosquitoes or mosquito. Tests on two men in the past show the virus can be found in semen. So, to be safe, many experts are telling men who travel to Zika-affected areas to use a condom for a week or so when they get back.
Does that mean it’s more likely to spread even more?
Experts say probably not a lot more but again, it is almost impossible to say for sure.
The good news is that Zika is not like it’s not like the AIDS virus HIV, or herpes, which stay in the body for life. The immune system can clear out the Zika virus and it’s usually gone from someone’s blood within a week. And it's only carried by Aedes mosquitoes, which stick to hot areas, so don't look for it in Minnesota or Maine, or even Florida in the winter.
How can I make sure I don’t get Zika?
If you’re traveling to a Zika-affected region, experts say the best way to protect yourself is to avoid mosquito bites. That means staying inside where there’s air conditioning and screens, using mosquito repellant, wearing long sleeves and long pants. The mosquito that transmits Zika and other viruses like dengue bites during the day, so that means taking precautions even when it’s hot.
Mosquitoes are sneaky and can bite through thin material, but you can spray a chemical called permethrin onto clothing and make it more mosquito-proof.
If you are not in a region where the virus is circulating, you really do not have to worry. Only a few dozen cases have been brought to the U.S. If you have sex with someone in a region where Zika’s circulating, use a condom.
What’s a safe repellent to use?
The Centers for Disease Control and Prevention says DEET is safe even for pregnant women and young children to use. But if you want to really look at your choices, the Environmental Protection Agency has an online guide.
The EPA has not tested many so-called natural repellents including citronella oil, cedar oil, geranium oil, peppermint, or soybean oil. But one product called oil of lemon eucalyptus (OLE) or para-menthane-diol (PMD) has been tested and found to be effective for older children and adults. “Oil of lemon eucalyptus products should not be used on children under 3,” CDC cautions.
What if I do get it?
There’s no specific treatment for Zika but the good news is you may not even know.
About 80 percent of those infected never realize it. The rest usually have mild symptoms. The worst are a raised, red rash, muscle aches, a fever and pinkeye. In some rare instances Zika may cause Guillain-Barre syndrome, a neurological disorder that can cause partial paralysis — scientists are looking into that. GBS can happen after a number of viral infections and so far there’s no way to predict who it will happen to or prevent it, but it is very, very rare.
The biggest worry is for women who may be pregnant.
Zika is suspected of causing microcephaly, a rare birth defect that affects brain development, and possibly some other brain damage in the developing fetus. The CDC advises women who know they have been infected with Zika to have regular ultrasounds to keep track of the baby’s development. No one knows if Zika really is causing microcephaly, and no one can say how often it happens or when the riskiest time of pregnancy might be.
So just to be safe, the CDC advises any woman who is pregnant or could get pregnant to stay out of Zika-affected areas for now.