Transcript for CDC Telebriefing: Zika Virus Travel Alert

OPERATOR: Welcome, and thank you for standing by.  At this time, all participants are in listen only mode.  After the presentation, we'll conduct a question and answer session.  To ask a question, please press the star and 1 and please record your name.  Today’s conference is being recorded.  If you have any objections, you may disconnect at this time.  

TOM SKINNER: We’ll be joined today by DR.  Anne Schuchat, the Principal Deputy Director of the CDC and DR. Tony Fauci, Director of the National Institutes for Allergy and Infectious Diseases, both providing opening remarks about the current outbreak of Zika virus infection.  We understand we are getting a lot of calls and a lot of interest in this story right now.  We want to try to provide you all with as much information as we can, and so we're having this telebriefing.  I’ll turn the call over now to Dr. Schuchat.  

DR. SCHUCHAT:  Thank you so much, everyone, and thank you for joining the telebriefing.  We’ll talk about what we know about the Zika virus, what we don't know, and what we're working hard to find out about.  We know many people are concerned or scared, and we want to answer your questions with what we do know now.  Zika is not a new virus, but what we are seeing in the Americas right now is new.  

Zika was first recognized in 1947, and it's caused occasional illness in Africa and Asia, but the first outbreak we know of occurred in 2007 in the small Pacific island Yap.  Last May, the first local transmission of Zika in the Americas was reported by WHO in Brazil, and by the end of the year, Brazilian authorities estimated perhaps a million suspected cases of Zika occurred there.  Substantial illness seems to have been occurring last spring, and by this fall, Brazil authorities recognized a concerning increase in the usually rare, serious condition among newborns, Microcephaly.  Consistent with the idea that some of the mothers of these babies had been infected with the virus early in their pregnancy, potentially harming their developing baby.  Zika is a mosquito-borne virus and causes mild illness.  Unlike the virus, Dengue, causing life threatening disease or life threatening symptoms.  About four or five people infected with Zika never have symptoms at all.  Those who are sick have mild symptoms, fever, rash, joint pain, and red eyes or conjunctivitis.  The symptoms last a couple days up to a week.  It's very rare for a person with Zika to get seriously ill or die, but increasing lines of evidence suggest that some women who are infected with Zika during their pregnancy may go on to deliver a baby with a serious brain injury.  

Here is what we know.  Brazilian health authorities initially reported more than 3500 cases of microcephaly, a serious birth defect in the past year following the Zika outbreak they experienced.  Laboratory tests at CDC strongly suggest a link between Zika infection and some of the poor pregnancy outcomes.  Brazil is continuing to verify findings on the birth defect. We don't yet know what other outcomes might be associated with Zika infection during pregnancy, and there may be other factors in addition to Zika infection that might have increased risk to the fetus.  More lab testing and other studies are in progress to learn more about the results of -- sorry, about the risks of Zika virus infections during pregnancy.  

We understand this condition is devastating to the affected families, and that this ongoing outbreak is concerning to everyone, especially for pregnant women, their families who may travel or live in the infected areas.  Zika virus spread in the Americas and its effect on pregnancy are new developments that we are working with partners to better understand.  Health authorities in Brazil reported an increase in Guillain Barre syndrome, a rare neurologic disorder in which a person's own immune system damages nerve cells leading to nerve damage or paralysis that lasts for several weeks or several months.  Most people fully recover, but it can take a few years to do so.  CDC is currently working with public health officials in Brazil to investigate whether there's any link between Zika infection and Guillain Barre. Next, I want to turn to the epidemiologic situation.  Zika cases are now confirmed in more than 20 countries within South and Central America and we've also seen a limited number of cases in the two U.S. territories, Puerto Rico and the U.S. Virgin Islands.  The virus is spreading throughout the Americas and we expect more countries to be affected.  All of the continental U.S. cases to date have been in people who traveled to a country where mosquitos carrying the Zika virus are circulating.  

We have not yet seen local transmission of Zika in the continental U.S., and by local transmission, we mean that a mosquito bites a person infected with Zika and that mosquito passes that infection on to another person through a mosquito bite.  Zika is spread to people by the Aedes mosquito.  They are common in parts of the United States, particularly southern states.  It’s possible, even likely, that we will see limited Zika outbreaks in the U.S.  The same kind of mosquito has caused limited U.S. outbreaks of Dengue and chikungunya virus, but no widespread outbreaks or epidemics in the continental U.S. as a result.  Other factors work in our favor here.  Our urban areas are not as densely populated as areas in central and South America, and we have widespread use of air-conditioning and stronger mosquito control.  Our experience with Dengue and chikungunya and the different living conditions lead us to believe that any outbreaks of Zika in the continental U.S. will likely be limited.  Of course this virus is fairly new to the Americas and we will remain vigilant.  

CDC experts are working intensively to learn more about the outbreak and providing people with the information they need to protect themselves.  We issued travel alerts for the affected areas as confirmation of the virus comes in, and we'll keep you alert as the situation changes.  We’ve provided guidance for doctors and other clinicians on pregnant women and infants including through our MMWR and additional clinician outreach efforts.  Labs here at CDC are helping state health labs with diagnostic testing and provided training and materials for labs in Brazil and throughout the Latin American region.  We’ve added Zika to the list of notifiable conditions so state health departments have to report to CDC so that we can track and respond to the spread of the illness, and we have a team on the ground in Brazil and are working with other international partners to learn more about this outbreak.  We have two research partnerships one underway, and one is going to be starting soon. So we are doing a lot, but I do need to tell you, community mosquito control may be difficult.  The methods that we have have shortcomings, and we have to work in the future to identify better options.  

However, for the general public, we want to make sure you know what you can do to protect yourself.  If you are pregnant, we recommend you consider postponing travel to a region with ongoing Zika virus transmission.  If you must travel to or you live in an affected area, talk to your doctor and strictly follow steps to prevent mosquito bites if you're pregnant.  You can find more information on affected areas and on how to protect yourself on the CDC website.  Reducing exposure to mosquitoes for anyone in areas where the virus is circulating is important.  Wearing long sleeves, long pants, using repellents like Deet, which we think is safe to use in pregnancy, and other protections like screens and air-conditioning to reduce exposure to daytime mosquitoes.  It’s important to remember that this is a rapidly changing situation.  As we get new information, we may need to update our advice.  At this stage in a relatively new health threat, information evolves quickly, and we expect that the situation will continue to change as we learn more.  We are working very closely with colleagues in the infected areas as well as at home to get the information we need, and as we learn about the virus and health effects, we will share what we know so you have the information you need to protect yourself and your family.  Now I want to turn things over to DR. Fauci.

DR. FAUCI: Thank you very much.  Good morning.  Thank you, all, for joining us.  Addressing the research efforts underway at the National Institutes of Health to combat Zika outbreak and its consequences.  The NIH is working in industry to accelerate research in areas ranging from natural history of the disease, basic research on the virus itself, disease pathogens, diagnostics, vaccines, and therapeutics.  Within NIH, we have long supported research on viruses and others, namely those viruses that are spread by mosquitoes, ticks, and other arthropods.  The category included Dengue, West Nile, and chikungunya, all of which have emerged in the western hemisphere in the past few decades.  With the emergence of the Zika virus, we are focusing efforts on several fronts into development of animal models and the virus on the body, especially in pregnancy.

We are also supporting along with the CDC, the development of diagnostic platforms that can rapidly determine if a patient is infected with Zika or has been infected either recently or in the past, and distinguish it from other viruses, particularly Dengue infection.  Such diagnostic tools will be critical to reassure the unaffected pregnant women in areas where Zika is occurring and pregnant women returning from such areas.  At the same time, NIAID researchers are working on vaccine candidates to prevent Zika virus infection.  It is to our advantage we already have existing vaccine platforms to use as a sort of jumping off point.  NIAID is currently pursuing at least two approaches to a Zika vaccine.  First, a DNA based vaccine using a strategy very similar to what we employed for another virus, the West Nile virus, as this vaccine was found in a phase one trial to be both safe and immunogenic, second, a live vaccine building on similar and highly immunogenic approaches used for the closely related Dengue virus.  While these approaches are promising, it is important to understand we will not have a widely available safe and effective Zika vaccine this year and probably not in the next few years.  Although, we may be able to begin an early phase one clinical trial actually within this calendar year.  We need to look at Zika virus in its context as the latest in a series of mosquito-borne diseases that expanded their reach in the past 20 years or so.  These include, as you heard, Dengue, West Nile virus just last year.  There will be others.  We need vaccine platforms that can be quickly modified for protection against emerging new threats and we need broad spectrum drugs effective against whole classes of viruses.  This has been and will continue to be an important area of emphasis for NIAID.  

In the meantime, we have issued a call to the research community to highlight our interest in funding a number of vital areas of research that are specific to the current threat of Zika.  In addition to accelerated research towards diagnostics, treatments, and vaccines, which I’ve already briefly discussed, we're calling for basic research to understand Zika virus infection; its replications, its pathogens and transmission, and we are developing animal models.  We’re doing study on evolution and emergence of the virus including the identification of factors that affect host range and variance. Studies of the distribution and natural history in collaboration with the CDC will be done.  Basic research on the mosquito vectors, competence studies for replications and transmission and host virus interactions as well as studies on novel vector control mechanisms.

Also, a valuation of the immune response, both to infection and to vaccination as well as evaluating the relative immune responses to Zika and other viruses and to some extent yellow fever, and in addition, the interaction of the responses and impact on the disease itself. Clearly, there are very many important areas of scientific inquiry, and we at NIH are in constant communication with government, academia, and partners in the United States and internationally including our long term collaborators in Brazil and other South American countries. NIH is actively pursuing answers to the numerous scientific questions related to Zika infection, and we are sharing this information in real time, refining our avenues for accelerating research. Such findings in these endeavors inform the global health response.  I want to thank you for the opportunity to speak with you today, and I would be very pleased to answer your questions. Thank you.  

TOM SKINNER: Kathy, I believe we are ready for questions.  

OPERATOR: Okay, thank you.  At this time, we have a question and answer session.  If you want to ask a question, press star 1 and record your name.  We are taking questions only from the media at this time, and one question with one follow-up.  Again, star 1 if you have a question.  Our first question comes from Mike Stobbe at the associated press.  

MIKE STOBBE: Hi, thank you for taking my call.  First, DR., you just talked about a call to the research community to highlight your interest.  Could you tell me how much money NIH is going to be devoting to this and how much of it -- what you've been spending previously on Zika research, and then I have a follow-up.  

DR. FAUCI: Okay.  That’s a good question.  As you heard, as said, this is a brand new virus, so we, prior to this time, have not spent anything on Zika.  however, we do have a substantial resource commitment to the virus class, so we spend about $97 million on the flavivirus research, and when you ask how much we're going to spend, it really depends on the kinds of requests coming in and the kinds of projects we're pursuing. So I can't put a number on it except to say we'll be utilizing the grantees and grants out there for the virus and immediately supplementing them.  I imagine that this is going to require a considerable amount of resources, but right now, we're just going to fund what comes in with the money we have, and if additional money comes in, then we'll, I’m sure, utilize it well.  We want the community to get actively involved, both with new ideas as well as tacking on to some of the other things we're doing with flavivirus.  One of the things I’ll point out that we've actually already started in the intermural program with the vaccine research center, the cementer involved in the development of the Ebola vaccine and others, that we're using the same platforms that we used to develop the West Nile to already get started on making the material that we would get into GMP grade to be able to start reasonably soon this year on a phase one trial, so things are moving rapidly.  

MIKE STOBBE: Okay.  Thank you.  Doctor Schuchat, could you go over the latest numbers for the U.S.?  How many cases, any pregnant women?  How many gave birth, and the territories' numbers, Puerto Rico, the Virgin Islands, how many there, and how many believed to have been transmitted there versus acquired through travel?  

DR. SCHUCHAT: Thanks so much, Mike.  The statistics for the U.S., first, let me talk about the travel-associated cases, there are 31 travel-associated cases detected in 11 states and the District of Columbia, from the period of 2015 to the present. And for the U.S. territories, there are 20 laboratory-confirmed cases that we are aware of, 19 from Puerto Rico, and one from the U.S. Virgin Islands.  I think for the pregnancy numbers, we'll get back to you later, but that is based on what has come in.  I would say that, you know, the issue of us making this nationally notifiable and laboratory testing for the lab confirmation with the PCR is just increasing, so we really do expect there to be a lot more travel-associated cases.  The key thing for people to know and remember is that most of these are very mild illnesses.  It’s really the circumstances of pregnant women who are traveling that we want to have heightened awareness of, and we really caution pregnant women to consider postponing travel.  We hope to know more and give more guidance in the future, but there's the best recommendations right now.  So, again, the issue for Puerto Rico and Virgin Islands is that that includes individuals who are laboratory confirmed.  They may be locally acquired or have traveled, but that's been detected in two of the places.  

TOM SKINNER: next question, Kathy.  

OPERATOR: This is from Hellen Branswell with STAT News.  

HELLEN BRANSWELL: Thank you very much for the question.  Before I ask it, I say that if you come up with numbers of U.S. cases that involve pregnant women, I’m interested in the numbers.  Doctor, earlier, the CDC did some pretty important work on samples from Brazil, finding Zika virus in the brains of two babies who had microcephaly that died shortly after birth, and also in placenta tissues from women who miscarried fetuses with this.  Are you testing additional samples from Brazil or elsewhere or found additional evidence?  

DR. SCHUCHAT: Thank you, Helen.  Tthis is a really important issue, and what I can say is we're working very closely with Brazil and other affected countries, that we just had folks down in the area doing laboratory training so that better access to testing could be done close to where the action is, and we're working closely with the state health departments on laboratory testing.  We did that initial MMWR when we had the lab findings.  We thought that was very important information for the public to know about and are continuing to look at this.  Now, a number of studies in Brazil are going to be looking at children with birth defects who were born quite a while ago, so testing will be challenging in those circumstances.  I would just say this is a very active effort right now, and there's prospective studies recognizing the laboratory component of the conditions.  

TOM SKINNER: Helen, do you have a follow-up?  

HELEN BRANSWELL: I ask, are you saying that you currently don't have any additional cases that you could speak about in terms of finding viruses that would support this theory?  

DR. SCHUCHAT: I think we reported what we are able to report right now, but we can check back additional ones if those are able to be reported.  I don't think we'll be surprised given the number of clinical episodes there's been and the extent of spread in the Americas for there to be additional confirmed cases in pregnant women. I think what we are really focusing in on more now is more detailed research understanding the factors that lead to increased risk of these condition, and, really, careful review of the clinical circumstances.  Microcephaly is a complex condition, and the surveillance or detection of it is not examples, and so we are working in other areas as well.  Putting together the clinical …. of such great concern and the laboratory findings is going to be a work in progress in the days and weeks ahead.  

TOM SKINNER: Next question, Kathy?  

OPERATOR: From Betsy McKay, Wall Street Journal.  

BETSY MCKAY: Thanks for taking my call.  I have two questions.  You mentioned a phase one clinical trial that may start later this year.  could you clarify which vaccine approach that would be -- which one of the approaches you mentioned – I thought you said West Nile, but I was not sure, and then the second question for Dr. Schuchat or Dr. Fauci, I wanted to follow-up on what Helen asked about, you know, what's known about disease in pregnant women.  Is there any way to know -- do you have findings showing whether pregnant women who are infected but don't get sick are at risk for their babies? Is there any way to know that at this point?  

BETSY MCKAY: Risk of microcephaly.  

DR. FAUCI: I was referring to the DNA construct in which we inserted a West Nile viral gene insert.  That construct, when put into cells, makes virus-like particles.  That is a study done that was done with West Nile and published in the Journal of Infectious Diseases in 2011, the first author, Julie Wedgewood, and saying modifying promoter produces neutralizing antibody in younger and older healthy adults in a phase one clinical trial. Since they are both flaviviruses and we can insert the mica gene insert, we feel we can get this construct reasonably soon ready to make enough to start going through the usual tox studies as well as getting into a phase one trial within the timeframe mentioned so there is a precedent for that.  Now, the reason why the West Nile virus phase one did not turn into a vaccine approved, produced, and made widely available is we could not find pharmaceutical partners to partner with us to push it to the next stage of advanced development.  I do not anticipate we'll have any problem partnering with pharmaceutical companies now because of the extraordinary attention and interest that is now put into Zika, and we're talking to companies to partner with us in advanced development.  

TOM SKINNER: do you have a follow-up?  

BETSY MCKAY: About the pregnancy.  

DR. SCHUCHAT: Yes, thanks.  I’ll speak to that.  Women who are infected with Zika virus without symptoms could have a baby with one of the birth defects.  First thing to say is that we don't know for sure.  We are working hard to find out.  I would like to say that it's possible, and that there are other viral conditions that can do that.  We’re taking it very seriously, and we know it's a difficult thing for women to hear.  It’s one of the reasons that we've urged women who are pregnant to consider postponing travel to the affected areas. It is a possibility, but we don't have the strong evidence of how often it happens or what the risk is.  

TOM SKINNER: Next question, Kathy?  

OPERATOR: From Lisa Schnirring with CIDRAP News.  

LISA SCHNIRRING: Hey, thanks for the availability today.  I’m wondering if anyone knows if you get infected with Zika, if that confers infection against possible infection in the future, and the question is during the WHO executive board briefing today, they mentioned a meeting in Washington to set research priorities, and I was wondering if that's something the U.S. government is involved in or maybe it's not.  Thanks so much.  

DR. SCHUCHAT: Sure.  I can begin.  You know, based on what we know now, we do think that an infection with Zika virus will confer immunity.  We don't actually know how long that'll last for.  This is a fairly new virus in terms of what we understand of it, and so we try to keep an open mind.  We also know that the tests for Zika are not as great as we'd like them to be in terms of availability or specificity, and so making sure that the -- that the immunity to Zika and not to something else takes additional  testing. So based on what we know about the infection and immunity right now, we think it's likely that one is getting long term protection, but we just don't know how long it is and we caution everything with a new condition like this saying that we're keeping an open mind.  

TOM SKINNER: Dr. Fauci, do you want to talk about WHO and research priorities?  

DR. FAUCI: Yeah.  There’s a number of meetings to take place over the next couple months in February over into March.  Meetings from international collaborators getting together to get and compare the research agendas and trying to synergize on research.  You’ll hear more of it.  We have our own groups here in the department in which we look at the research agenda with the CDC, the FDA and other components of HHS, and also meeting within the U.S. government, but the U.S.  Government will be participating in those international workshops that are going to be looking at a broad international research agenda.  So the answer to the question is, yes, we know about it, and we will be participating.  

TOM SKINNER: Next question, Kathy.  

OPERATOR: All right.  Next question comes from Sabrina Tavernise, the New York Times.  

SABRINA TAVERNISE: Hi, thanks for taking my question.  I’m trying to piece together, the Brazilians had confusing numbers.  They gave our reporter in Brazil the following numbers that only, like, six or seven of about 700 microcephaly cases analyzed had Zika or exposed to Zika.  Is there a way to explain that or confusion?  Leads one to the conclusion that, actually, there's little association to Zika and microcephaly.  

DR. SCHUCHAT: You know, thank you for the question.  You know, what I can say at this point in an ongoing investigation, information is being gathered, and so the Brazilians are the best source on exactly what information they have right now.  Remember, they are piecing together review of episodes that occurred quite a while ago.  They are collecting specimens of those they find, may or may not have tested large numbers, and it's for us to decipher that, and there are many ways to study this kind of issue, and try to clarify how strong a risk factor of Zika virus infection would be for a pregnancy complication, and so both the experience the Brazilians have had and prospective studies are very important.  CDC is working closely with Brazil and other countries and the rest of the community that works on birth defects day in and day out to try to really understand this.  It’s a very difficult issue, really important, and I think we're going to have challenging information coming out over the weeks ahead until we can really clarify this situation.  I’m sorry that I can't piece it out for you.  

SABRINA TAVERNISE: That’s okay.  One follow-up.  Could you speak directly to what the risk is for Americans in the United States?  Everybody’s saying, oh, mosquitos are everywhere, and others say we have air-conditioners and window screens so the risk is low.  Break it down into simple English.  

DR. FAUCI yes, are you referring to the risk now, for example, with mosquitos, as Ann said and should chime in, we don't have local transmission of the virus in the United States right now, so we are getting questions that are understandable. People are nervous saying I live here now and I was bit by a bunch of mosquitos.  

SABRINA TAVERNISE Exactly.  What do you say?  

DR. FAUCI You say there's no risk at all because we don't have locally transmitted Zika virus in the United States.  I mean, that's an understandable concern when they really read about the massive outbreak in South America and the Caribbean, and that's why Ann and I when I talked about this over the last week or so when we talk about it make sure we distinguish between a local transmission within a country and a traveler that just comes back and happens to have Zika infection.  There’s a big difference there.  

SABRINA TAVERNISE Yeah.  And what's the factors that are stopping local transmission?  

DR. SCHUCHAT:  I can share about that.  You know, we have the mosquito that carries the virus in the United States, and we have transmission of other mosquito borne infections in other areas of the southern united states, but we have not seen large outbreaks, and the factors going into that include the dense urban areas in south America or central America where some of the outbreaks have been described.  The living conditions where we have most people with access to air-conditioning or screens versus a much more outdoor open air lifestyle, and then that density of population where it makes it easy for mosquitos to hop around between people.  The level of mosquitos is more intense in some of the areas where mosquito control is not as strong as it is here, and so we do expect we are at risk for local transmission, and we're not surprised to report that.  I do -- I don't want to give misconception here-- we're expecting there to be some local transmission, but based on the experience with the other mosquito borne viruses and those areas in the southern united states, we are not expecting really big difficult to control ones.  That said, we're going to jump on this if we find local transmission and work closely with the local authorities to better control the problem. For the average American who is not traveling, this is not something they need to worry about. For people who are pregnant and considering travel to the affected areas, please, take this seriously.  It's very important that you understand that we don't know as much as we want to know about this yet, and while we're learning more, it's prudent to consider postponing travel, and if you must travel, talk to your health care provider and protect yourself from mosquito bites.  

TOM SKINNER: Next question, Kathy.  

OPERATOR: Liz Szabo from USA today.  

LIZ SZABO: You mentioned that mosquito control could be difficult in the United States, and I was hoping you could elaborate on that.  

DR. SCHUCHAT:   Yes.  You know, we've done well in terms of some of the insect-borne diseases in the U.S., but controlling mosquitos, this type of mosquito is somewhat difficult.  The current options have limited efficacy.  They include elimination of breeding site, larva treatment, and outdoor spraying to kill adult mosquitos.  These are pretty aggressive daytime biters, and so you don't need huge amounts of mosquitos to be able to have a mosquito infect a person, and it's really hard to knock them out totally, so I think our researchers feel that better vector control is a real important area to invest in in terms of research and strategies.  You know, there's some innovative approaches looked at-- both different products, different attempts to do better vector mapping and ecological and where to intervene.  There’s methods to monitor insecticide resistance and improve methods to minimize development of resistance.  We think large scale intervention trials will be needed to understand the effectiveness of different approaches, but, you know, it's easy to say get rid of the mosquitos.  It’s harder to do it.  

LIZ SZABO: Okay.  Thanks.  What about the prospect that sometimes mentioned about the genetically engineered sterile mosquitos?  

DR. SCHUCHAT:    Yes.  The idea of the genetically engineered sterile mosquitos is intriguing.  At this point, it's unproven on a large scale, but it's a really exciting idea, and important to understand community acceptance and how to take on the research question in a larger scale.  We’re gratified that individuals are looking into these innovative approaches, and we really encourage more of that because I think the mosquitos are probably going to outlive us, and it would be good for us to find better methods.  

LIZ SZABO:  Okay. Thanks.  

TOM SKINNER: Next question, Kathy?  

OPERATOR All right.  Our next question is from Eben Brown, Fox news.  

EBEN BROWN:  Hi, good morning, and thank you for doing this.  These questions, two of them, for either doctor that wishes to answer.  First, we talked about mosquito control.  Here I’m calling from south Florida.  Mosquito control is a political situation meaning that we have -- we have elected officials who deal specifically with mosquito control and boards.  What should towns think about doing?  Second question, there was an article, I think, within the past week, suggesting that there was a case of sexually transmitted Zika virus between a husband and wife, husband traveled, may have gotten sick, wife who did not travel became sick.  It was revealed that they were intimate upon his return.  Could you comment on that, please, and is that really something we ought to be worried about, or is it too soon to tell?  

DR. SCHUCHAT: Thanks for those questions.  Let me take them in reverse order.  There is one reported case of Zika virus through possible sexual transmission.  In another case, Zika virus was found in semen two weeks after a man had Zika virus infection.  That gives you the plausibility of spread, but the science is clear to date that Zika virus is primarily transmitted to people through the bite of an infected mosquito.  I don't know if an infected mosquito can transmit, but that's really where we put the emphasis right now.  In terms of the local mosquito control issues, those are difficult issues.  I think that communities need to understand what's known about the benefits and risks and work together with the authorities to understand what's going to be acceptable.  I do think that there's a lot of innovation that we're excited about understanding, and we know that the Brazilians are very interested in exploring more effective approaches, but I think in terms of your local Florida situation, you know, the community discussions will be important to continue.  

EBEN BROWN Great, thank you.  

TOM SKINNER: Next question.  

OPERATOR: Question is from Caleb Hellerman, PBS News Hour.  

CALEB HELLERMAN: Hi, thank you.  I’m just following up on a question of how many cases you're expecting to see, and, obviously, after this report, you'll get many more calls.  Also, based on the range and the behavior of this mosquito in the Americas, and, of course, headed into warm weather.  What do we know about the seasonality of the other related infections and when we might start to see large spikes in cases, and how do you think people should view the numbers that inevitably start to look big?  

DR. SCHUCHAT:  Right.  We do expect and believe the virus is widespread in south America in that we will have travelers infected with it coming back and detected, and part of that would be about how many of them present to get tested, and so there is some experience from the chikungunya virus, relatively new virus to the Americas, and it did occur among travelers, and we actually got large numbers of  reported travelers, but in terms of local transmission, it was miniscule, you know, a handful of local transmission, whether it's been either virus. So I think we need to be prepared to have numbers of  cases among travelers to go up quite a bit, but we don't think it's a concern for the average American.  We think that's just going to be a sign of a good surveillance system, but we really think what's important is that pregnant women consider postponing travel to affected areas, and that in the areas where the mosquito can circulate like south Florida, that we have very active surveillance and detect conditions quickly so we can intervene as effectively as possible.  So I think that, you know, we have a certain amount of comfort because we have been through the experience, but we also know this is a new virus to us, and we have to keep an open mind.  

DR. FAUCI: So let me add a brief comment to that because I’ve been asked a lot of questions about this.  First of all, we always say as Ann reiterated a few times, and I totally agree, that a lot we don't know so we have to be very careful in making absolute predictions.  We still feel based on prior experience that as Ann said, and I agree, it is unlikely we're going to see widespread joint outbreaks and be prepared for that.  If that happens, that's not going to be an unexpected phenomena to see a limited cluster, very likely in the southeastern part of the country along the gulf coast and Florida the way we saw it with Dengue.  The other thing that's important is that you see in several newspaper articles, they show the map of distribution of the southeastern part of the country and greater distribution of the other mosquito that may or may not be able to first timely transmit that.  We don't know yet.  Don’t make the assumption, then, that you'll see outbreak this that distribution of mosquitos.  That’s just where they are.  We are being prepared, and we're not going to be cavalier about it that it is being spread, but that is highly unlikely as we said multiple times.  Be prepared for it, but that's not something that we expect to see based on the experience with the other viruses.  

DR. SCHUCHAT: And I think you also asked about the seasonality and, you know, based on the situation with the viruses in south America, the seasonality can vary by country and year so every year we can see big differences in, you know, how bad a year it is or not, so I think, again, with this being relatively new to the Americas, we'll be very interested in understanding seasonality, and that'll be important information for travelers to learn about, but we don't have that yet for this virus.  

TOM SKINNER: Next question, Kathy?  

OPERATOR: Next question comes from Lorna Benson of Minnesota Public Radio.  

LORNA BENSON: Thank you for taking my call.  I’m wondering if there's any risk to the blood supply regarding blood donations, and then, secondly, I wonder if there is a difference in risk depending on -- for pregnant women, depending on what trimester they are in.  Thank you.  

DR. SCHUCHAT: Thank you.  The blood supply is of great interest, and I think I want to say that the FDA is looking at the issue of blood supply, donors, and travelers.  One thing we know about Zika virus is it's in the bloodstream very briefly.  It’s not, as far as we know, there for a long time, so that most people who cleared their bloodstream of the virus by about a week, so we think this is an issue the FDA deliberates about in terms of blood donors.  The second question you had was about the trimesters, and, of course, these are questions we are keenly interested in having better answers for.  We do believe that the injury of microcephaly begins in the first trimester, but we don't believe we have sufficient knowledge now to know what, if any effects infection in the second and third trimester would have. We know that there are other viruses like rubella that cause birth defects including hearing loss, vision loss, and heart defects, and, you know, even major brain damage.  There are different effects at different times during pregnancy, so we really feel for the women pregnant living in the endemic areas and know it's a challenging time for them, and our scientists are working closely with counterparts to understand better.  

LORNA BENSON:  Thank you.  

TOM SKINNER: Kathy, I know we have possibly a lot of questions and reporters in cue.  Go to the next question, go for ten more minutes.  Next question, please.  

OPERATOR: All right.  Richard Knox, WBUR Boston.  

RICHARD KNOX: Thank you.  A couple things, one having to do with Puerto Rico, which we know has enormous financial problems right now.  I don't know whether that is going to interfere with the ability to have the response of this initially, but I wonder from the CDC, what is happening with regards to Puerto Rico being a challenge and what needs to happen.  

DR. SCHUCHAT: Thank you so much.  You know, one of the CDC installations, our branch is based in Puerto Rico.  We have 40 or so staff based there working very closely with the Puerto Rican health authorities and experts, so we are very closely linked in with the Puerto Rican health experts and community, working closely to assure surveillance is ongoing and to get information to the community.  There’s the research rein surveillance efforts and building on that is exactly the right thing to do for the community there.  They have good surveillance.  They have great lab testing and good communication and expertise, and an ability, we hope, to really recognize how widespread it is and what interventions will be most effective, so I think this is a huge priority for us at the CDC and across the government.  You know, these are Americans in Puerto Rico, and we're committed to be working closely to protect their health.  

RICHARD KNOX: Thank you.  I just wondered do you have any worry about the ability to mount widespread mosquito abatement possibilities?  I have another question, if I may.  

DR. SCHUCHAT:  Yes.  As I mentioned before, mosquito control is very difficult, and we are very keen to learn what works in this context to try to identify areas of the major transmission or major breeding grounds are.  We know that the mosquito control is just one of the many interventions.  We think it's really important for people to protect themselves because we might not be as successful in controlling the mosquito as we'd like.  Again, that means long pants, long sleeves, use treated clothing, wearing Deet or similar repellant that's safe in pregnancy, safe for children up over two months of age, and under two months, there are ways to protect them through nets and so forth in terms of their bed and all that.  It’s important for us to work closely in Puerto Rico with the community and that the mosquito control, while important, is not the only thing that we have to offer.  

TOM SKINNER: Next question.  

OPERATOR: From Dan Childs, ABC News.  

DAN CHILDS: Thank you very much for taking the question.  The first question I had was from the doctor, a short one, do we happen to know the case count in travel associated Zika in each state?  You mentioned 11 states, D.C., and then, also, for women who are not pregnant but plan to be down the line, do we know enough yet that the link to microcephaly is only seen in cases when the infection is still active or any association that the associated risk linger longer than the symptoms do?  

DR. SCHUCHAT:   Okay.  Thank you.  We have not yet released the state by state counts.   Think that's one of the things we'll expect to be doing at some regularity, so stay tuned for that, as I mentioned before, we are expecting a lot of travel associated cases, and so the numbers may not be that critical, but we are working with state colleagues to get the information out on a regular basis, but, probably not on a daily basis.  Then the other question was about how long the infection might be active in a woman in potentially causing harm to her baby.  We believe this is a time limited infection in women and men and children that people have symptoms up to a week, and so we don't think this is one where you have months or years of chronic viral infection that could cause harm to the baby.  So we know that four out of five people with the infection we believe have no symptoms, so it's complicated to know, well, when did this start and stop.  Our scientists are working closely with counterparts on some investigations to understand this in a more rigorous way.  Based on what we know right now, we think it's an active period of infection that may or may not have symptoms, and it's short limited, short time.  

TOM SKINNER: Kathy, we have about five more minutes, so let's go to the next question, please.  

OPERATOR: Next question is from John Lauerman of Bloomberg news.  

JOHN LAUERMAN: Hi.  So what is the state of research right now to establish the connection between these birth defects and Zika virus?  How is that being pursued?  

DR. SCHUCHAT: let me give you kind of a general outline.  You know, the first thing that's very important is very careful, clinical review of the information on the babies that have been recognized with birth defects.  Microcephaly itself has some looseness around what it is and we want to make sure that the infant really has that condition, but there are many other birth defects that can be present in a child, so we think that the pediatricians, genetics, and health experts in Brazil and elsewhere and CDC carefully review the records. There's also plans to specifically be following a cohort of pregnant women to really understand do they get infected or not with the virus and what happens over time during the pregnancy, and then what happens with the babies, and that's the kind of study that's quite intensive, large scale, to detect a rare problem, and we'll, obviously, be a major collaboration, so that work is not yet gun, but discussions are very active about that because I think the field believes that's very important. There's also a collaboration between Brazil and CDC and possibly others around using a case controlled design to compare babies with microcephaly condition and other babies born around the same time in and around the same area to look in more depth at different factors that the mothers were exposed to, and to look at laboratory tests from the mothers and babies, and really get a better idea of what proportion, if any, of these birth defects can be specifically linked with the Zika virus, so I think there's a host of things that are being looked at, but those are a couple of the ones that are high on the list.  

JOHN LAUERMAN:  Thank you.  

TOM SKINNER: Next question, Kathy?  

OPERATOR: Next question's from Sandy Lamount of CNN.  

SANDY LAMOUNT: Thank you very much for taking my question.  do you have the exact listing up to date that you're saying are 11 so we can update the map --

TOM SKINNER: Sandy, this is Tom, we hope to be providing that information to you soon when we get things synced up, but we'll provide that hopefully to you soon.  Do you have any question?  

SANDY LAMOUNT: I do.  And that had to do with specific areas that were, I think, looked at for historical, looking chikungunya and the United States, what areas of the United States did that include?  

DR. SCHUCHAT: Yeah.  I think those are the southern tips of Florida and Texas and perhaps other similar tips of the south.  I’m trying to recall if California’s on the list -- not on that list?  Okay.  So, you know, there's been a little, and, you know, again, those are very small local transmissions.  

DR. FAUCI: In the Florida keys and Dade county in 2012, there was a small cluster that was taken care of by vector control, but it was in the Florida keys and in some cases in Dade county.  

SANDY LAMOUNT Thank you.  

TOM SKINNER: Kathy, we'll take one last question, please.  

OPERATOR>> Okay.  One moment.  We have a question from Nora Kelly, at The Atlantic.  

NORA KELLY: Thank you for making yourselves available.  My question is, it's my understanding that El Nino is expected to bring heavy rain in the south over the next few months, how much a concern is that for mosquitos breeding?  

DR. SCHUCHAT We, of course, we’re concerned about heavy rains for many reasons in terms of the damage that that can cause.  In terms of the risks for this particular virus and spread in those southern tips of Florida and Texas, that is not a major concern.  We think the critical issues are to be doing good surveillance and actively recognizing when there's local spread and to follow-up pretty actively of control at that point. We do think the living conditions in general in the united states, the lack of urban density in those areas where the mosquitos circulating and the air-conditions and screens will hopefully keep us in better shape compared with what's beginning on in some of the hot spots in south America or the Caribbean.  

DR. FAUCI Yeah.  Also, an interesting question comes up talking about people who bring up the topic of climate change and very dry or very wet.  mosquitos are very interesting species that sometimes changes in climate that you think might propagate them, actually, make it less favorable for the mosquitos, so sometimes climate changes make it either worse in the sense of more mosquitos or even better with fewer mosquito, and it really depends on the relative extend of dryness versus wetness which are all consequences of extremes of climate.  

TOM SKINNER: All right.  Kathy, I believe we're ready to conclude our briefing here.  Thanks to the doctors and thank you to everyone for joining us this morning. We’ll continue to share information with you as we have it.  A transcript of the telebriefing will be posted to the CDC news room website as soon as possible.  We realize some of you were not able to ask your questions, and should you have additional questions, please, call the CDC press office at 404-639-3286 or e-mail CDC to media@CDC.gov.  Thank you very much.  

OPERATOR: Thank you, this completes today's conference.  You may disconnect at this time.   

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U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES