In a breaking news update that came out after this chat occurred, the CDC updated its Zika virus guidance for pregnant women, advising each to protect herself if her male sexual partner has traveled to or lives in an area where the virus is circulating.
"Until we know more ... you should abstain from sex or use condoms the right way every time," the CDC says.
How serious is this latest development in the fight against the virus, and what can you do to protect yourself?
Dr. Sanjay Gupta, CNN's chief medical correspondent, has been following the Zika outbreak and went on Facebook on Wednesday to take questions. Here are the highlights from the live video chat, edited for brevity and clarity:
How did the CDC confirm that the Zika virus was transmitted sexually?
A man who returned from a trip to Venezuela and wasn't feeling well. He and his wife were tested for the Zika virus and both were found to have it. She had not left the United States since 2008, so as a result of putting that all together, they determined she contracted it sexually.
How did these cases of the Zika virus suddenly explode?
Someone got on a plane in an area with Zika virus circulating. They flew to a country where mosquitoes that can carry the Zika virus are flying around. The transmission starts once the mosquito bites that person, then bites someone else.
What are the symptoms?
Four out of five people with the Zika virus won't have any symptoms at all, so will likely never know they had the virus at all. Twenty percent will have flu-like symptoms, which may include rash, redness of the eyes, fever and joint pains. This sort of infection can feel like a lot of other infections and be hard to distinguish. The biggest concern is for women who are pregnant.
If they contract Zika virus, there's seems to be a possibility it could cross the placenta, get into the amniotic fluid and cause microcephaly, a birth defect affecting brain development where the baby is born with an abnormally small head.
Is microcephaly purely cosmetic?
The microcephaly that is being caused by the Zika virus is not purely cosmetic. Microcephaly
literally means small head, small brain.
Their are children who are born with microcephaly who can have relatively normal cognition. But you have to look at why the microcephaly occurred. With an infection like this, they have found evidence of a virus interfering with the way the brain actually developed. If it interferes, this is not all a cosmetic concern. This is a concern of cognitive, intellectual and developmental delays.
We know that some 4,200 children have had microcephaly over several months. To give you some context: There were about 146 children in a year period before, so the numbers definitely spiked. We also know that 51 of the children have died. So this is not just a cosmetic concern.
If you're a woman traveling to a country where the Zika virus as spread, but have no desire to have children, should you worry?
If you have no desire to have children, you should still make sure you aren't pregnant. If you are not pregnant, you have very little reason to worry
Will the Zika virus lower birth rates?
It's possible you will see lower birth rates, but I don't think it will be significantly lower because it's just not practical to do some of the things these governments are recommending.
How long can the virus stay in your system?
What we're hearing is that the virus can stay in your system for about seven days. The Red Cross is saying that they don't want you to donate blood for 28 or 30 days after you get back from one of the affected places. Part of the reason they wait so long is that they want to be careful. There's an abundance of caution.
Is this a virus that can stay in your body forever?
It does not appear that this is one of the viruses that stays in your body. Unlike the AIDS virus, this does not appear to be one that hides and shows up at a later time. If you been exposed to the Zika virus, it's likely that you won't be infected with that same virus again. Your body will develop a natural immunity.
Can you get tested for the Zika virus?
The testing is not widely available yet. There's going to be more expanded testing, but for now, most of the testing goes to the Central Disease Control to actually be confirmed.
Can a vaccine be developed?
This is almost a philosophical question. I'm an optimist.
I think it's possible a vaccine can be made, but it may be a little more complicated for what seems to be a relatively simple viruses. With Zika, even if you have a good candidate for the vaccine, you want to test it. The way people typically test vaccines is in the midst of outbreaks. You vaccinate a certain number of people and have a control group that doesn't receive the vaccine, then basically see if the vaccine has an impact.
It takes time, years -- even under the best circumstances, but you are talking about three to five years at least until we have a vaccine.
Should the Olympics in Brazil be canceled?
I don't think the Olympics should be canceled, but there clearly has to be precautions taken. If I were a pregnant woman, I probably would not go to the Olympics -- not with what we know right now.
Should people traveling with small children to Brazil be concerned?
Pregnant women and unborn children are at the biggest risk. But children are susceptible to mosquito-borne illness just like adults.
How far can we expect the Zika virus to spread?
We're not likely to see widespread outbreak of Zika in the United States, Europe or many parts of the world. This is in part because of basic amenities: air conditioned venues, screened windows, access to insect repellant. All these sorts of things make a huge difference.