The tropical Zika virus continues to make headlines as the first sexually transmitted case has occurred in the US. We talked with David Itkin, MD, an infectious disease specialist at Portsmouth Regional Hospital in New Hampshire to better understand the latest Zika virus developments.
How serious is the risk of sexual transmission?
Nobody knows at this time. It’s such a rapidly moving and evolving area. We’ve had one case reported of sexual transmission, but what we don’t know about sexual transmission is huge. We don’t know if someone who is acutely infected is likely to transmit this to somebody who is a sexual partner, or if it’s a tremendously rare and unlikely event. We also don’t know at what stage someone would be contagious sexually. Is this something that could be transmitted through a short period of time, or is it something that is prolonged? So, at this point all that can be said is that there is a risk, and we cannot state for how long someone is at risk sexually after acquiring Zika infection.
If you’re pregnant, or may be pregnant, and your partner is someone who could have Zika virus infection or come from an area with Zika, then the safe thing to do is to be abstinent or use condoms for protection throughout your pregnancy.
The risk pregnant women face is the unknown risk of congenital infection to the baby.
What should pregnant women know about the virus?
Pregnant women are not any more susceptible to acquiring the infection, and there is no information that states the mother would have a more serious infection than those who are not pregnant. The risk pregnant women face is the unknown risk of congenital infection to the baby. The travel advisories are something people should watch carefully, and take into consideration. If someone is pregnant and is traveling to an area where Zika is present, they should strongly consider postponing travel. Above and beyond that, there are appropriate measures people can take to protect themselves against mosquitoes. The advice is different than what one might do in the United States, because this species tends to bite during the day and at night, and they are indoor biters as well. So people should use a more aggressive approach to mosquito protection if they’re going to be in an area where Zika is transmitted.
If you’re a woman who is not pregnant and doesn’t plan to be in the near future, is it safe to travel to these regions?
It is as safe as it would be for anybody else. The Zika virus infection is not like Ebola, which causes a serious, overwhelming and life-threatening infection. Only about 1 in 5 people exposed to Zika become symptomatic, and the symptoms -- rash, fever, achiness, muscle and joint pain – are usually mild to moderate. There is not a strong travel advisory for otherwise healthy people traveling to Mexico or the Caribbean. People who go to an infected area and get the virus will feel as though they have a mild version of the flu that maybe lasts up to a week.
The main concern is the risk of congenital infection and the possibility of microcephaly in developing infants. That is why pregnant women are singularly targeted.
How long does the Zika virus stay in your system?
Looking at similar viruses in this viral family, we would suspect that the virus would be relatively short lived within the human body -- and certainly, one would not expect this to be a latent virus, such as herpes or HIV, that persists for life. People who get Zika will show symptoms for a relatively short period of time, but how long they're contagious is really not known. That's part of the reason for the Centers for Disease Control and Prevention’s fairly conservative recommendations for pregnant women with a partner who has come from a Zika-infected area.
What do people need to know about the Zika-carrying mosquitoes?
Unlike the mosquitoes carrying the West Nile Virus, the Aedes mosquitoes, which carry Zika, are very aggressive biters. Aedes mosquitoes commonly breed in small pools around households like flower pots, drainage from drain pipes, and other small, inconspicuous areas. That's why it's hard to control them, because there are a lot of small areas to target.
The most surprising thing is how rapidly the Zika situation is unfolding.
What’s most surprising to you about Zika?
How rapidly the situation is unfolding. We’ve seen the spread of dengue and chikungunya, which are actually carried by same mosquito, over the last several years in the Americas. But the explosion of Zika seems to be so much more rapid and dramatic than those other viral diseases. The other thing that nobody could’ve predicted is that it has a large emotional component. Zika poses a risk to the developing fetus, which is a unique feature that makes it stand out and makes it so frightening.
I would go as far as saying that if this was just a widespread viral disease in the Americas that was not associated with congenital infection of developing fetuses, then this wouldn’t have garnered any of the concerns, fears, recommendations and guidelines that have come up.