Transcript for CDC Telebriefing: Zika Virus Update – July 29

Press Briefing Transcript

Friday, July 29, 2016, at 1:30 P.M. EST

Please Note:This transcript is not edited and may contain errors.

OPERATOR: thank you for standing by.  Today’s conference be begin shortly.  Again, thank you for standing by.  Today’s conference will begin shortly.

OPERATOR: Thank you all for standing by.  The conference will begin momentarily as we wait for more to join the conference.  Again, today’s conference will begin shortly.

>>> Thank you for standing by.  The conference begins momentarily as we await more participants to join.  Again, today’s conference will begin shortly.

>>> Welcome, and thank you for standing by.  Welcome to the Zika conference.  You’re in listen only mode until the question and answer session.  If you have a question then, press star 1.  Today’s update is recorded.  if an objection, disconnect at this time.  we have the chief media branch, and thank you, ma’am, you may begin.

KATHY HARBEN:  thank you, holly, and thank you for joining us today for a briefing on Zika.  We have Dr. Tom Frieden joining us, director of the CDC and Dr. Marc and that’s m-a-r-c, Fischer, f-i-s-c-h-e-r. He’s a Medical officer in CDC’s Arboviral Disease Branch and He’s currently deployed to assist Florida in their Zika investigation.

TOM FRIEDEN:  Hello, everybody, and apologies for the delayed start.  We had a lot of interest in the call so it took a while to get everyone joined in.  Thank you for joining.  As you know, Governor Rick Scott and the Florida health department announced four cases of Zika infection that are the result of local mosquito-borne transmission, these are first cases reported in the continental United States.  We’re working closely with Florida and we’ve been impressed by the comprehensiveness of their investigation.  These cases are not unexpected.  At CDC, we’ve been saying for months based on experience with Chikungunya and Dengue which are viruses spread by the same mosquito that spreads Zika, that individual cases and potentially small clusters of Zika are possible in the U.S. As we have anticipated, Zika is now here.  We are proceeding as though the cases are confirmed local Mosquito-borne transmission.  To be clear about this because it can be confusing, confirming mosquito-borne transmission is not as easy as confirming infection in a person.

Our best evidence would be if we found Zika in one of the Aedes aegypti mosquitos in the area where there are cases reported. But that is very difficult to do, it is like finding a needle in a hay stack.  Whether — if infected mosquitos are not found, that doesn’t imply that it’s not spreading by mosquitoes. If they are found that’s highly suggestive. But it’s not expected that we would find infected mosquitoes even if there is spread by mosquitos in that area.  The Zika cases are in both Miami-Dade and Broward counties.  The Florida Health Department has focused on one small area several blocks just north of downtown Miami where active transmission of Zika appears to have occurred in early July.  All the evidence we’ve seen indicates that this is mosquito-borne transmission that occurred several weeks ago.

Importantly, since these infections were diagnosed, Florida has implemented aggressive mosquito control as they do for all the travel associated cases there, of which they have had close to 400.  Florida is aggressively working to reduce mosquitos in the area of the reported cases. They’ve been going door-to-door to reduce standing water.  They are spraying by truck and backpack both for adult mosquitos and larva mosquitos, and we’re coordinating closely with Florida and will continue to support efforts to assess the situation on a daily basis.  We at CDC continue to recommend everyone in areas where mosquitos are present, especially pregnant women, take steps to avoid mosquito bites.  That means applying Deet repellent every day to exposed areas of skin, on arms, legs, neck, and face.  Wearing long sleeves and pants.  And staying indoors or in screened areas as often as possible.

We at CDC offered Florida supported laboratory testing and vector control as well as other aspects of the investigation and response and we are clear that we are ready to go as soon as they ask.  We would not be surprised if additional individual cases are reported.  In fact, there may well be more cases we’re not aware of right now because most people infected with Zika do not have symptoms.  People infected weeks ago may have infections diagnosed as we do, as Florida does, community surveys in the area.  If, however, we were to see cases in this area in people infected after the mosquito control efforts were undertaken, this would be a concern and warrant further advice and action.  We will continue to update you with what we know, when we know it, and in the meantime, everyone all over the states where Aedes aegypti mosquitos are present, especially pregnant women, should take steps to avoid mosquito bites.  We understand that people want more information.  We understand that Zika is scary, especially for pregnant women.  We wish we had all of the answers, and we know that Florida’s working hard to reduce the risk of Zika and protect pregnant women.  The bottom line, again, is that Zika is now here.  It’s particularly important for pregnant women to avoid mosquito bites in all areas where the Aedes aegypti mosquito is present by using Deet, wearing long sleeves, and avoiding mosquito bites to protect themselves.  We’ll now open this up for questions.

OPERATOR: Thank you.  If you’d like to ask a question press star followed by the number 1 and record your first and last name when prompted so i can introduce your question.  one moment, please, for incoming questions.  Our first question is from Mike Stobbe with the Associated Press.  Go ahead, your line is open.

MIKE STOBBE: Hi. Thank you for taking my question.  I was wondering a couple of things.  Are there plans now to do more active surveillance for cases?  i — please correct me if I’m wrong, but I was under the impression these four cases were identified through past surveillance so will Florida health officials or anyone be going into clinics, hospitals doing more blood testing and I was wondering if you could say more about what areas had this active mosquito eradication, in the Wynnwood area or other areas?  Also, do you have any advice for women in the Miami area who are considering conceiving?  Should they put that off for some amount of time, or what’s your advice?

TOM FRIEDEN: thank you.  Well, first in terms of active case findings, there are several things that the Florida health department is doing.  The first is encouraging doctors to think Zika. People have symptoms that may be consistent with Zika. second in the areas where local mosquito-borne transmission is considered, the Florida health department with CDC input and dr. fischer’s presence with the Florida team have done community surveys, knocking on doors, not only to eliminate standing water, but also to ask people to participate in the survey so we might be able to identify if there were other infections through testing there.  So that’s a form of active surveillance or active monitoring that could help define the area of concern or the extent of the problem.  In terms of decisions about whether and when to become pregnant is a highly personal decision.  Right now, the area that we’re concerned about is a several block area in North Miami and for that area, my understanding is that the Florida health department will recommend that women who are pregnant consider getting a test for Zika even though the odds are low of infection. Always better safe than sorry, always good to be prudent, and I’m sure people want to have that information.  They will then have access to it.  We provided Florida with test kits and are available if there is a surge in testing requirements to support the needs of people who want to get tested there.  Next question.

OPERATOR: Our next question is from Eben Brown from Fox News, go ahead, your line is open.

EBEN BROWN: Thank you very much for taking the call.  We kind of all had known this would happen, and I’m remembering back to the original press call we did about Zika which if I remember was hastily called on a Friday night.  Did this happen sooner than was expected, or was everyone ready, sitting around waiting for the first transmission?

TOM FRIEDEN: Well, while we can’t predict the future, this is really the time when we would expect to see cases. It’s the upswing of mosquito season, it’s similar to times when we’ve seen Dengue and Chikungunya in the past and in July and August, so this is the time Frame that we thought would be most likely.

EBEN BROWN: Thank you.

TOM FRIEDEN: Next question.

OPERATOR: Next question from Betsy McKay from the “Wall Street Journal,” your line is open.

BETSY MCKAY: I had a couple questions.  One is, I was wondering if you can shed light why the focus is on the one mile square area, is this a place of residence for the four people?  One from Broward county, so they don’t live there, but I’m wondering how much time they spent in the area.  Second question is, one of the four is a woman.  Is she pregnant?

TOM FRIEDEN:  So for the details of that, I have to refer you to Florida and for situations like, whether someone’s pregnant or not, confidentiality often prevents us from discussing that in either direction.  The investigations have been of multiple cases that have occurred.  Which may represent local transmission on more than one occasion. what’s concerning about this particular area is that more than one of the cases were associated with it, and it was their only association and the investigations there identified significant number of mosquitos that can spread Zika.  Those conditions were rapidly abated. But that’s why it appears that this is an area where there was some local transmission in early July.


TOM FRIEDEN:   Thank you.

TOM FRIEDEN:  Next question.

TOM FRIEDEN: Operator next question, please.

OPERATOR: Our next question comes from Jon Cohen from Science Magazine.  Go ahead, your line is open.

JON COHEN: I wanted to follow-up with what Betsy was asking.  The — I think we’re very confused when we’re told that there were reports of it being both Miami and Miami-Dade and Broward and now just Miami.  We have to clarify that or we’ll misreport it.  i also think it’s unusual for us to be told of a restricted area like this for a mosquito-borne virus; regardless of whether it was the Florida department of Health. What does the CDC think of the Florida Department of Health issuing this restricted area in a map?

TOM FRIEDEN:  Thank you. so first off, residences are in both Miami-Dade and Broward; however, where it appears transmission occurred is in this several block area in Miami, and we are fully in agreement with outlining the area providing it so that there’s transparency and people can know and people in the area can help with mosquito abatement, getting rid of standing water, for example, but there’s a very important point here, and I don’t know if it’s behind your question.  There’s a huge difference with mosquito — between mosquito control for West Nile, which many of you are familiar with, and mosquito control for Zika.  With Zika, it’s a very focal disease.  The Aedes aegypti mosquito does not travel more than about 150 meters in its lifetime – and often quite a bit less than that.  In contrast, with West Nile, you have virus circulation within a bird, mosquito population that can cover a large area.  That’s a totally different situation from what we have with Zika where it’s a focal in areas like this where it’s a focal problem that needs to be addressed focally.  Does that answer your question?

JON COHEN: Well, it’s still confusing why a resident in one county would be assumed to have been affected in another county.

TOM FRIEDEN: The epidemiologic analysis strongly suggests that the exposure and the infection occurred around the workplace because of the connections between people who don’t have other connections. So the Florida investigation identified in the course of their interviewing of patients and assessment of environments, that this location was likely to have been the source for more than one case of Zika spread locally.

JON COHEN: Thank you.

TOM FRIEDEN: Next question, please.

OPERATOR: our next question comes from Dr. John LaPook.  Go ahead, your line is open.

DR. JOHN LAPOOK: Yeah.  Hi, Tom. I have a question.  I know that local blood donations have been suspended, but there’s a window between when the active infection occurs, several weeks ago and now. So during that window, there was potential for somebody to donate blood and for it to be infected.  Have people gone back to look at the blood supply and look at whether there’s any evidence of infection?

TOM FRIEDEN: Well, first off, my understanding is that the blood bank for the area is beginning testing of blood as of today.  In terms of past transfusions, I would have to refer you to the FDA because they have regulatory authority over that.

DR. JOHN LAPOOK. Okay, thanks, Tom.

TOM FRIEDEN: Thank you.  Next question.

OPERATOR: Our next question from Elliot Rodriguez with WFOR Miami.  Go ahead, your line is open.

ELLIOT RODRIGUEZ: Hi, thank you for taking my question.  I’m here in Miami, you can imagine how concerned people are about this.  I wanted to clear up, you said residences are in Miami-Dade and Broward but these people were infected in Wynnwood –were they at the same place, workplace, I’m fuzzy on that.  And also, Wynnwood is a popular restaurant and entertainment district in Miami.  Would you recommend people stay away or pregnant women stay away?

TOM FRIEDEN: Thank you.  The investigation identified more than one individual who appeared to have been infected near each other in that location.  In terms of travel into the locations, we don’t currently see a situation where we would advise people not to travel there or advise pregnant women not to travel there. If, however, cases were to continue in the area, even after the mosquito control activities had been undertaken, that would be a very different situation, and so at present, we understand that some people may decide not to go there, and that’s an individual decision, that they are free to make and they have the information from the Florida Health Department about where the investigation is taking place and where the intensive mosquito control activities are undertaken, but at this point, we do not see an indication to advise people or pregnant women not to travel there. However, anyone there, anyone in Miami, anyone in any city or state where the Aedes aegypti mosquito is present, especially pregnant women, should use Deet, use long sleeves, long pants, and avoid mosquito bites.  For pregnant women, that may involve staying indoors, air-conditioning as possible or screened space for as much time as practical.  Next question, please.

OPERATOR: Our next question comes from Nancy cook with “Politico.”  Go ahead, your line is open.

NANCY COOK: Thank you so much for taking my question.  My question on two parts.  one, I’m curious about what the delay was, you know, both the press release and you just said Florida has known about this since early July wondering if you could explain to me why we’re just now having confirmation of local transmission.  And then Two, more broadly, does CDC have a sense of what the time frame that Zika will remain in the U.S. is?  is it just a problem for the summer, or do you think it will be a problem that extends into 2017?  Thank you.

TOM FRIEDEN: So on the first — let me really clarify this.  The individuals appear to have gotten infected in early July.  They got sick about a week later.  They got diagnosed a couple days later. Immediately after that, Florida did what they do for all of the Zika cases including travel associated.  They went to the area, and they began killing mosquitos.  That’s the right thing to do.  They also, for all of the nearly 400 cases they have had, do a thorough investigation to see, did that person travel, have sexual contact with someone who might have had Zika?  Is there another explanation for their Zika infection, and in the cases that Governor Scott mentioned today, they concluded that there was no other explanation except local transmission of Zika, and that conclusion is not simple to make.  There’s no simple test for that.  Mosquito pools are rarely positive, if they are it’s very helpful, but they’re rarely positive. I think this is a complex investigation, and we’ll certainly continue to share information as soon as we have it.  In terms of the future, I think every indication is that Zika will continue to spread in parts of Latin America and the Caribbean in future years.  It may spread at a different level, it may become more of an endemic than an epidemic situation, but only time will tell.  That’s why it’s so important we strengthen systems to monitoring for Zika, inform people how to protect themselves, and continue to develop new and better tools to diagnose it and prevent it.  Next question.

OPERATOR: our next question comes from Pam Belluck with the New York Times.  Go ahead, your line is open.

PAM BELLUCK: Hi, thanks for taking my question.  Just to clarify, you said just a few minutes ago that all the people appeared to have been infected near each other in that location, which I think you were referring to the work place, right?  They were all infected near each other?  In or near a particular workplace, is that the right way to think of this?

TOM FRIEDEN: So, there are details of the investigation to refer you to Florida to address.  There are multiple cases that are consistent with local mosquito-borne transmission.  Of those cases, at least some of them are associated with the area in the map from the Florida Health Department where there were at least two individuals who were nearby each other and who developed Zika.

PAM BELLUCK: And nearby each other as coworkers?

TOM FRIEDEN: No.  They were in different work sites but close by.

PAM BELLUCK:  Okay, okay, okay.  So the four people are not all related?


PAM BELLUCK:  Okay. Okay. Thank you.

TOM FRIEDEN: Thank you, next question.

OPERATOR: Our next question comes from Donald McNeil with The New York Times.  Go ahead, your line is open.

DONALD MCNEIL: Hi.  Back in January when there was local transmission like this, the CDC issued advice saying pregnant women should stay away from entire countries with transmission, and now you’re not telling people to stay away from one square mile?  This does not seem consistent, and so it looks like bowing into pressure from the Florida tourism industry.  why not issue a travel advisory as you did last time?

TOM FRIEDEN: it is completely consistent.  we issued guidance for Puerto Rico because we anticipated and predicted what has occurred since we predicted it, that there would be widespread explosive spread of Zika in Puerto Rico.  what we also said at that time was that there are likely to be isolated cases in the u.s., and there may be occasional clusters in the u.s.  we don’t expect widespread transmission in the continental u.s.  if, however, we were to see continuing spread in this area or somewhere else, or explosive spread, then we would absolutely issue travel guidance.  That’s not the situation that we’re in today, but we will reassess that every single day, and based on what we know now, we are not issuing travel guidance, but that could change depending on events as they occur here and elsewhere in the u.s.  We are applying exactly the same standards within the u.s. and outside the u.s.

DONALD MCNEIL: well, when is it a precaution just because you don’t know if the mosquito killing is effective or not.

TOM FRIEDEN>> you know, by that reasoning, donald, you could issue a precaution for all 30 states where the mosquitoes are present because four out of five diagnoses are asymptomatic.  we don’t know where it’s spreading.  we are taking a pragmatic approach to support the community and the state and protecting people by providing information and reminding everyone, especially pregnant women, whether or not Zika has been diagnosed in your community, just use insect repellent, wear long sleeves, and avoid mosquito bites.  next question, please.

>> the next question comes from lena sun from the washington post.  go ahead, your line is open.

LENA SUN hi.  i was wondering if you could elaborate on something.  you said that there are multiple cases that are consistent with local mosquito born transmission, and at least some of them were infected in the area on the map, so that — that’s before what governor scot talk about, but how many more cases are we talking about that are locally transmitted?

TOM FRIEDEN>> well, as per governor scott’s announcement, they identified and confirmed as of today, four cases that are locally transmitted.  for details of the investigation, i refer you to Florida, but let me emphasize something.  Again, remember that four out of five Zika infections are asymptomatic.  So if we find a singleton case of locally transmitted Zika in community X, that doesn’t necessarily imply that that community is at any higher risk of Zika than all of the other communities with the mosquitos present because four out of five of them won’t be found.  as we look back to the other viruses—dengue/chikungunya, the vast majority, nine out of ten or more of the introductions of that virus have been dead ends.  They’ve only infected one person and not resulted in the cluster.  We have a small number of clusters identified and investigated in the past in Key West and a couple of communities in texas.  Generally, when cases come in, they dead end after infecting one person.  that’s partly because our environment is not that conducive to mosquitos, partly because people use screens and air-conditioning.  For whatever the reason, we don’t generally see clusters.  here, we are seeing at least two cases associated with a location where there’s large number of mosquitos present, mosquito abatement was done immediately after cases were diagnosed even before they were confirmed to be locally transmitted, and the thing we’re looking at very carefully here is: is there anyone there who gets Zika after that mosquito control intervention?  in that case, it’s a different situation.

>> okay.  thank you.

>> thank you, next question.

OPERATOR comes from megan rosen with science news.  go ahead, your line is open.

MEGHAN ROSEN:  > thank you for taking my question.  you just touch on this a little, but i’m wondering if you can talk about the risk of larger outbreaks given what we already known about local transmission in Florida.

TOM FRIEDEN: We’ve learned a lot in recent years about control.  there are some environmental situations making it more difficult than others, so in some environments where there’s lots of standing water and people don’t have screens and air-conditioning, it’s much harder to control, especially if people are close together.  in other situations, the mosquito is in what is for it a marginal environment where it’s harder to survive and easier for us to knock down populations with mosquito control intervention, so this is why we said we believe that widespread transmission in the continental u.s. is unlikely, but it’s not impossible.  that’s why we’re aggressively keeping our guard up and investigating every possible incident that may represent widespread transmission.

>> thank you.

>> next question.

OPERATOR: >> kimberly leonard from u.s.  news and world report.  go ahead, your line is open.

KIMBERLY LEONARD: yes, hi, thank you for taking my call.  could you explain pretty well for me the needle in the hay stack and how it was difficult to confirm 100% that it was local transmission, but the language in a lot of the releases says likely transmission.  does it seem to be it’s confirmed?  if it’s not, are we still considering that Zika might have another mode of transmission, and that’s why we use the term “likely”?

TOM FRIEDEN: everything we’ve seen so far indicates this is mosquito-borne transmission.  there’s not a test to confirm that unless we’re lucky enough to find Zika in a mosquito.  we are considering this and proceeding as though it is confirmed local mosquito-borne transmission.  next question.

>> next question from michael with  your line is open.

MICHAELEEN DOUCLEF  yeah.  I’m wondering if you can talk about the blood supply and testing.  do you know if there’s enough kits available in the county to test the blood supply, and are counties asking for them?

TOM FRIEDEN: there are two kinds of tests here.  one is a test of the blood supply, and there are ample tests available to screen blood.  The FDA indicated that blood should be screened scene the blood bank that covers the area is, as we understand, has said they will start that today.  there’s no shortage of kits for blood screening, and the food and drug administration would be the place to go for any follow-up questions about the blood supply.  For testing kits, generally, testing people who may have Zika, there’s also ample supply for people who are pregnant, have symptoms, or are in the area and have concerns.  the tests are provided by CDC or developed by laboratories including the Florida health department and are available through health departments and through clinician offices.  we’ve worked closely with four different commercial laboratories to get a range of tests available in private laboratories to make it easier for patients to get tested, and we hope that in the next few weeks, they’ll be able to get that testing started in the commercial laboratories as well.

MICHAELEEN DOUCLEF: so right now, the tests are only available through the health department —

TOM FRIEDEN: >> no.  People can get tested if they have an indication for testing at any doctor’s office.  Their doctor’s office coordinates with the health department to get the samples sent to where it needs to go to be tested.

>> next question, please.

>> our next question comes from dan childs.  go ahead, your line is open.

DAN CHILDS: thank you so much for holding  this call.  a two-part question.  given, as you said, that four and five people who are infected show no symptoms.  are there any projections on how many other cases right now there might be that we have not detected, and then, also, the second part of the question is, how close are we to knowing asymptomatic people infected can be receivers of the disease.  are there any ongoing studies to help tell us this?

TOM FRIEDEN>> so a couple things there.  we don’t have projections, but, again, we believe that about four out of five people with Zika infection don’t have symptoms, so we anticipate there’s going to be other infections.  after all, individuals who got the infection ultimately got it from a mosquito who got it from another other who had Zika because they traveled somewhere where Zika was spreading.  we do know with certainty that people with asymptomatic infections with Zika, women with asymptomatic infections of Zika, can give it to the fetus that can get microcephaly from that asymptomatic infection. We also know with certainty that asymptomatic infection also has virus in the blood and also can result in the spread of Zika through mosquitos.  we’re not yet certain whether that also holds for the sexual transmission of Zika, which may require a larger inoculant, but we’re just not sure.  we don’t have any reason to think it doesn’t, and so we say anyone who traveled to an area where Zika is spreading like latin america and parts of the caribbean, should use a condom until the end of the pregnancy if their partner is pregnant.  time for two more questions.

>> your line is open.

DAN VERGANO>> thank you, can you talk about the status of funding for CDCZika efforts right now, how much cash do you have?  when does it run out?  how are you doing, basically?

TOM FRIEDEN:>> we are doing the best we can with the resources we have available to us, and the authorities available to us.  if we had more resources, we would be able to mount a more robust response, and this is certainly an example of why it’s so important that as proposed by both houses of congress, both parties, that there be an infectious disease rapid response funds for resources and authorities for rapid action.  last question, please.

TOM FRIEDEN:>> thank you.  so i’ll just wrap up here.  i do want to correct one thing i said earlier.  it is now confirmed that asymptomatic infection can result in sexual spread of Zika from a male partner to a female or to a sexual partner, so that has now been confirmed.  we’ve said from day one that we are learning more about Zika literally every day.  we do everything we can to inform the public about that as soon as we learn it.  the bottom line here is that Zika is now present in the continental united states.  we identified, the Florida health department has identified a small cluster of cases in a several block area just north of downtown Miami.  the transmission there appears to have occurred in early july.  by mid-july, the health department had already conducted aggressive mosquito control activities there.  we continue to monitor the situation on a daily basis, and everyone, particularly pregnant women, anywhere, where the aedes aegypti mosquito is present, should protect themselves against mosquito bites by applying insect repellent, wearing long sleeve shirts and long pants, using or repairing screens on windows and doors, using air-conditioning when available and removing standing water where mosquitos can lay eggs.  thank you all very much for joining us today.

KATHY HARBEN:>> thank you, doctor Frieden, and also, thank you reporters for joining us.  if you have follow-up questions, you can call the press office at 404-639-3286 or you can e-mail us at  thank you for joining us.  this concludes the call.


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