KELLY MCEVERS, HOST:
Health authorities in Brazil announced today they have discovered active Zika virus in saliva and urine. They're telling pregnant women not to share cups or eating utensils with other people and they should be careful about kissing people. But health authorities in the U.S. say there's no evidence that Zika can spread through saliva and urine. Joining us now to talk about all this is NPR health correspondent Rob Stein.
And, Rob, so when the authorities in Brazil say they've found active Zika virus in saliva and urine, what do they mean?
ROB STEIN, BYLINE: Yeah. Well, Kelly, you know, this isn't actually the first time that anyone's found any evidence that Zika can be found in saliva and urine. You might remember there was - the first big outbreak of this virus occurred in French Polynesia a couple years ago. And back then scientists detected evidence of genetic material in people's saliva and urine, but what's different here is scientists in Brazil, they took samples from two infected people, they brought it into the laboratory and they exposed it to cells in the laboratory and showed that the saliva and urine could actually infect cells. And that raises the theoretical possibility that the virus could be spread that way but the emphasis is on theoretical.
MCEVERS: Why is it only theoretical?
STEIN: Well, you know, it's a big jump to go from detecting the virus in saliva and urine to say that you can actually catch it that way. And the reason is it could be lots of reasons why even though it's there, it can't infect anybody. There may not be enough of the virus present or there may be other substances in the saliva and the urine that keep it from infecting other people. So you remember, there, you know, are other viruses that are found in lots of bodily fluids that don't infect anybody with anything. HIV, for example, can be found in saliva and in urine and even tears, but nobody gets AIDS that way.
MCEVERS: All right, but we now know that Zika is not only spread through mosquito bites, right? I mean, there was a case in Dallas of someone who got it through sexual contact so that's obviously a very real risk, isn't it?
STEIN: That's right. The virus has been found in semen in that Dallas case of sexual contact, and that prompted the CDC today to issue advice to pregnant women for how they could protect themselves from getting infected through sexual contact. And what they said, basically, is that if you're a woman who's pregnant and your sexual partner either lived in or has traveled to parts of the world where Zika's spreading, you should either abstain from sex or use condoms every time you do have sex to protect yourself from getting infected. But they stress that the - it's really important to remember the main way Zika spreads is through mosquitoes. That's by far the overwhelmingly dominant way you can get Zika.
MCEVERS: What are they saying about the risk - the wider risk - of the disease here in this country?
STEIN: Well, the CDC and other health officials are saying, you know, look, we have the mosquitoes in this country that spread this virus so there is a possibly that it could start to spread. So far, there's no evidence that that's happened yet. There's been a total of 51 cases confirmed in this country. One of them was this person who got infected through sexual contact. The other 50 - all of them were all travelers who picked it up some place else and then brought it back here.
That said, since the mosquitoes are here, you know, there's a pretty good chance that at some point it probably will spread, but they don't think there's a very good chance that it's going to spread widely. And the reason for that is we do a really good job in this country of controlling mosquitoes, and there've been other diseases - similar diseases like dengue and chikungunya that have come to this country and spread the same way, and there's been a little bit of spread but they've been able to contain those outbreaks really fast.
MCEVERS: That's NPR Health Correspondent Rob Stein.
STEIN: Oh, sure. Thanks Kelly.
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