and ford. we go further, so you can. >> we were in mosul with an iraqi special operations brigade as they met isis head on. >> it's not like a regular army they're fighting. this is en masse a suicidal army. >> on the front lines we saw what the fight is likely to look like, and what isis is willing to do to hold on to this city. >> how many of you are voting for your candidate, raise your hand? three. how many of you are voting against a candidate? everybody else. >> on the eve of the presidential election, with

polls showing deep voter dissatisfaction, we asked pollster frank lutz to put together a focus group to find out why. he conducted hundreds of these across the country. and everywhere he goes he hears pretty much the same thing. >> how many of you would say that we are mad as hell, raise your hands. just about everybody here. ( crying ) >> zika is one of the most dangerous viruses the head of infectious diseases at the n.i.h. has ever seen, but-- >> people don't take it seriously. >> how do you not take it seriously? when you see the babies-- >> but people don't, people don't. >> how do you explain that. >> you don't know somebody who has a microcephalic baby yet. yet. >> tonight we'll bring you behind the scenes in the rush to fight zika now that it has hit the u.s. >> how many warehouses like this are there? >> i can't tell you that. but we can reach any part of the u.s. within 12 hours or less.

>> i'm steve kroft. >> i'm lesley stahl. >> i'm bill whitaker. >> i'm lara logan. >> i'm scott pelley. those stories tonight on "60 minutes." >> cbs money watch sponsored by american express open, proud correspondenter -- supporter of growing businesses. >> quijano: good evening. preelection jitters have the s&p on a losing streak, the longest since 19 80. the colonial gas pipeline that exploded in alabama last week reopened today. and wendy's, kohl's and macy's are among the companies reporting earnings this week. i'm elaine quijano, cbs news.

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>> kroft: the battle for mosul began in earnest this past week as iraqi forces began the long, hard fight to defeat isis there. it was 2014 when this historically important industrial city of some two million people was stormed and captured.

today much of its civilian population is trapped between isis and the advancing iraqi army. with turkey to the north and syria to its west, mosul is located on the tigris river well north of baghdad. if there was ever any question what a full on war against isis fighters would look like, it is on full display in mosul, and you will see it in this story tonight. lara logan and a 60 minutes team joined an iraqi special operations brigade from the golden division as it fought isis neighborhood by neighborhood. the battle for mosul is already a brutal one and some of the images in our story are graphic. lara logan has our report from the front line. >> logan: when we arrived at their forward base in east mosul, the golden division had just begun their push into the city. (shouting) only 30 minutes later an iraqi soldier shouted, "it's coming to us, it's coming to us."

an isis suicide car bomber was racing toward them. one of our cameramen, scott munro, pointed his camera at the road in front of the building. (explosion) >> everybody okay? everybody okay? (gunfire) >> logan: what's going on? gunfire erupted. another suicide car bomber was trying to break through. (gunfire) they'd stopped the first bomber before he reached the entrance to our building. and by now, every weapon within reach was firing. their defense seemed to re-route the second bomber, who disappeared from view. major salam hussein is the commander here.

he's proven to be one of iraq's most effective weapons against the islamic state, or daesh, as they're known to iraqis. it happened so fast. >> salam: so fast because the houses are so close they just use civilian cars to attack our forces. >> logan: so this is more of what you can expect in mosul? >> salam: yes. >> logan: a black crater burned into the earth marked the spot where his men stopped the bomber. there was little left of the car, just pieces of metal strewn, and the engine, still smoking. that's the bombers shoe. you've been fighting isis ever since they took mosul in june 2014. right? >> salam: yes. >> logan: how many operations have you commanded against daesh, do you know? >> salam: i don't know, we're talking thousands. a thousand. >> logan: how far is the enemy's side there?

how far from us? major salam used a drone, his eyes in the sky, to search the streets for any sign of the second bomber. suddenly, another drone was overhead-- it was the enemy's. everyone was ordered off the roof. (gunfire) isis makes their own drones. we were told this one carried c4 explosives and targeted major salam. salam wanted to show us how long isis had been preparing for this battle, so he brought us to this open tunnel system not far from their base. it's purpose: to provide cover and run fighters from village to village. >> logan: this runs from where? >> salam: from bartella all the way to mosul. >> logan: all the way to mosul? and how far is that? >> salam: about 25 kilometers. >> logan: 25 kilometers or about 16 miles long. and nine feet down lay the bodies of isis fighters his men

had just killed. >> we try to know who they are. i mean, they are iraqi, arab. >> logan: the golden division punched through mosul's city limits last week. since then it has been engaged in intense combat and taking back a fraction of the city. major salam knows more about isis and its fighters than almost anyone. his elite soldiers fought them when the iraqi army wouldn't. in mosul, keeping the civilians safe is one of his main priorities. we saw hundreds of them-- women and children fleeing, carrying all they could, including white surrender flags. salam said isis has used a different strategy in every city but they always fight to the death. he told us they have killed 150 of his soldiers. >> logan: you almost were killed in fallujah. >> salam: the rocket go through the window and blow inside the vehicles. and i found myself bleeding. i didn't care if some part of my

body got cut or something like that. i tried to stop just the pain on my head by any way. >> logan: you should not be sitting here right now. you should be dead by now. >> salam: yeah. >> logan: we'd been together for a matter of hours and had already encountered a suicide bomber, a drone, and just outside major salam's headquarters... (gunfire) snipers. our team ran for cover. you can hear the snap of the bullets. cameraman richard butler was there first. we were pinned down for few minutes until major salam's men sent this bulldozer to cover us from the sniper. as the light faded on our first day, we watched the major brief commanders about the plan for a major advance the next morning.

he'd be leading the assault from this part of the eastern front. they shared concerns about pressure coming from the iraqi government to push forward too fast. >> logan: do you think they'll attack you before you attack them? >> salam: they will attack us before we attack them. >> logan: no one is sure how many isis fighters are in mosul. but the iraqi army told us they believe there are around 5,000. it's the city where the group's leader declared the establishment of their caliphate. three years after america withdrew combat troops from iraq, the u.s. military is back providing support on the ground and, notably, the skies above. can you win this fight without the support of american air power? >> salam: it will be possible but it will be difficult. our forces will bleed more.

>> logan: will you say it's critical to your forces? >> salam: we fight for our families, we fight for our kids, and we fight for iraq. (gunfire) major salam has a reputation for leading from the front, and while we were with him, we found that to be true. (gunfire) (shouting) this was the deepest advance into isis-controlled mosul. the enemy was ready. 60 minutes cameraman richard butler filmed these images from major salam's convoy. for much of the offensive you couldn't get out of the vehicle to film because you were under such heavy fire. >> richard butler: you just couldn't get out. (gunfire) i mean they had the... you know, the back of the humvee when we went out was... you know, stacked with ammo. and... >> logan: and you went through it all. >> butler: and we were down to 400 rounds, which might sound a lot. but... >> logan: that'd be gone in a

few minutes the way they were fighting. (gunfire) >> butler: the way that fight was going, 400 rounds wouldn't get you 60, 70 seconds of firepower. (gunfire) >> butler: it's not like a regular army they're fighting or like regular insurgents or even terrorists. this is, en masse, a suicidal army. (gunfire) >> salam: they used everything. the used the car bomb, they used r.p.g., they use the snipers. >> logan: casualties were brought back to the base, from the fight a mile away. 16 hours later, major salam's men had taken back more ground from isis. he looked for a building to set up a command post in the newly captured neighborhood. >> butler: i went where major salam had gone in a little courtyard and they were trying to open the door to the house and it was locked.

it had a metal gate over the door and they tried to kick the door in. so he immediately sat down by the wall, got out his ipad and was looking for another location close by that he felt they could move to and no sooner had he put his finger on one we heard... (explosion) it was massive and it just... first of all, the shockwave. then chunks of metal. then glass, dirt, body parts, you name it, came raining down. and some people were stunned. it's so much... it sucks the oxygen out. so it's hard to breathe.

takes time to get reoriented. the moment my hearing came back, i could hear the rounds coming in. to their credit, you know, the soldiers that had been blown off their feet were back in the fight. >> logan: major salam lost four men in that last suicide attack, including his chief of security, who was a close friend. that's him behind the major just hours earlier. >> salam: these soldiers tried to, they thinking protecting me more than anything else. i'm sorry it happened, but i mean this is the war. we lost a lot of brothers in this war. >> logan: we spent 48 hours on the eastern front in mosul. not a lot of time but enough to know what this fight is about: a terrifying street by street struggle against an enemy who

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imy moderate to severeng crohn's disease. i didn't think there was anything else to talk about. but then i realized there was. so, i finally broke the silence with my doctor about what i was experiencing. he said humira is for people like me who have tried other medications but still experience the symptoms of moderate to severe crohn's disease. in clinical studies, the majority of patients on humira saw significant symptom relief. and many achieved remission. humira can lower your ability to fight infections, including tuberculosis. serious, sometimes fatal infections and cancers, including lymphoma, have happened; as have blood, liver, and nervous system problems, serious allergic reactions, and new or worsening heart failure. before treatment, get tested for tb. tell your doctor if you've been to areas where certain fungal infections are common, and if you've had tb, hepatitis b, are prone to infections, or have flu-like symptoms or sores. don't start humira if you have an infection.

if you're still just managing your symptoms, talk with your gastroenterologist about humira. with humira, remission is possible. >> kroft: in two days, americans will go to the polls and hopefully bring down the curtain on a contentious presidential

campaign that's been going on now for a year and a half. it is no secret that most americans are angry and disappointed with the process and the choices that they have been offered. that was confirmed last week in a cbs news/new york times poll that found 82% of likely voters more disgusted than excited about the election. we asked republican pollster, public opinion analyst, and cbs news consultant frank luntz if he could put faces and voices to this dark national mood by scientifically selecting a focus group that would reflect those polling results. and he did. some members leaned towards trump. some leaned towards clinton. some were uncommitted and most of them had an unfavorable opinion of both presidential candidates. >> luntz: you're going to go third one in. >> kroft: on thursday night, frank luntz began assembling a small group of carefully selected voters. he has spent decades doing market research, sampling public

opinion, and developing the right phrases and approaches to reshape it. and he has used the raw data from these focus groups to develop strategies for republican candidates, corporations in crisis, and celebrities in need of image makeovers. he is at the top of his field and a familiar face in boardrooms and newsrooms. >> luntz: so let's do a vote, let's do a vote. how many of you are voting for your candidate? raise your hands. three. how many of you are voting against a candidate? everybody else. >> kroft: luntz has conducted hundreds of these focus groups during the campaign with registered voters all over the country. and everywhere he's been, he's heard pretty much the same thing. >> luntz: i want you to describe how you feel about this political process with the election only hours away. i want you to give me a word or phrase. >> not substantive. >> terrified. >> too long. >> terrified. >> it's rigged. >> exasperating. >> circus. >> disturbed. >> horrifying. >> disheartened.

>> annoyed. >> disgusted. >> luntz: this is horrible. >> kroft: who are these people that we saw? >> luntz: these are 23 people representing all aspects of the political spectrum, all aspects of economic life, all age groups. i was looking for people that could have a legitimate conversation about these presidential campaigns and not just totally smear this candidate or this candidate. and here is my problem. >> kroft: they smeared both candidates? >> luntz: they smeared both candidates. we began with trump. a word or phrase to describe donald trump? >> unworthy. >> immature. >> racist. >> there's no words to describe him. >> nightmare. >> the kind of pig that every woman has always had to deal with. that (no audio). >> luntz: and i thought, "oh my god. i recruited only pro-hillary or mod... or neutral towards hillary." and then we moved to the clinton conversation, and it was just as bad. >> luntz: give me a word or phrase to describe hillary clinton. >> corrupt. >> entitled liar. >> train wreck. >> scandalous. >> dishonest. >> kroft: one of the things that struck me is that i knew that there were republicans, and i

knew they were democrats, and i knew that there were people that were undecided. but i really couldn't tell who was who. >> luntz: because the republicans are mad at trump, and the democrats are mad at clinton. and the bernie sanders people are mad at everybody. when has that ever happened? >> kroft: frank luntz traces the toxic political atmosphere back to the 2000 presidential election. al gore won the popular vote, but after six weeks and a supreme court decision, george w. bush became president. >> luntz: and in that six weeks, we came from being democrats and republicans to being outraged, to believing that the other side is trying to steal the election. and when the election was over, there was no coming together. there was no honeymoon. and from that point on, the goal has been to delegitimize. not to respect and-and at least to listen to, but to delegitimize the opposition. and now today in 2016, hours from now, it will be tens of millions of people who will believe that the loser should

have won, that the election was rigged, and that the winner is illegitimate. tell me something positive about this campaign season. >> something positive about this campaign season. wow. i would say... dang it. >> luntz: you can't come up with anything? >> it's hard to say something positive when you have people who are mad as hell. it's very hard to find positivity when people are pissed. >> kroft: but luntz was much less concerned about the negativity than he was about the tenor of the discussion. there was a deep, unfocused anger that crossed political, racial and economic boundaries, something he says is much more dangerous. >> luntz: how did we get to this point where every one of you with different backgrounds, different politics, different objectives, all of you gave me a negative reaction?

how did we get here? one at a time, no more talking over each other. >> bernie was cheated out of the election, that's how. >> he was not cheated out of the election. >> he was cheated. he was cheated. >> luntz: how did we get here? >> it's our fault. you saw it here, everybody's arguing. i'm afraid to even bring up a point. i'm not pro trump, but i see why people like it. and, you know, if i say that, i'm going to be, you know, ostracized. >> my biggest fear is that these candidates aren't a mistake. that the american people have elected the future of america, what we aspire to be and what we are deep down inside. i think trump has gotten so much traction at this point because deep down inside there are a lot of americans that feel the exact same way as him. (overtalk) deep down our coun... our country is divided, i'm sorry. we are not united. we are at each other's throats. and i'm sorry. maybe this is what it is. maybe these are the candidates that we want. >> luntz: i want to listen to them. i want to ask them questions, and then sit back, and let it all roll over me. and the problem is people become so angry. and they become so vicious.

>> kroft: this is new? you've been doing this a long time. >> luntz: it's never been like this. look, i did this for you 18 years ago. we were talking about the impeachment of a president, and each person spoke their turn. no one talked over each other. nobody yelled at each other. >> black people are actually killing more black people than... (overtalk) >> luntz: today, there's none of that. >> so if they disagree with you, their opinion shouldn't matter. (overtalk) but you say people who don't support donald trump shouldn't talk so much. (overtalk) >> luntz: it took two minutes for them to explode. it took five minutes to actually get to the point where i lost control. >> and guess what happened with clinton... (overtalk)

>> luntz: stop, stop, stop. >> kroft: one way to look at this is, okay, people are upset. and they're just blowing off steam. >> luntz: that was not blowing off steam. that got way too personal. they got way too strong with each other. and this is now my craft. this is what i've done for over two decades. that's not blowing off steam. that is a deep-seated resentment. >> luntz: is this america? are you... look around. are you america? yes or no? >> yes. >> you know, we don't... we don't know how to listen to each other. >> nobody will listen to any... >> can i say one thing? we don't know how to listen to each other. you know, we go on facebook all day and we just blast out messages into the ether. but we don't actually take time to see what comes back. >> look at how social media is. i mean, there's so much ugly stuff that we say to each other on social media where we attack each other, you know, we attack each other's views, we attack each other's, you know, heritage. >> kroft: what's happened in american culture? why is there this lack of civility? some people talked ab... a lot

of people mentioned social media. >> luntz: it's... it is social media. but the first question is: are you going to edit this? or are you going to play the words they actually used? there were people in that focus group who used language that if my mom was still alive and i said it, she would literally cut me out of the will. there's no self-censoring. so we now say exactly what we feel. and, goddamn it, you're gonna listen to me. and that's really what it is right now. you're gonna listen to me. i'm not gonna learn from you. you're gonna listen to me. >> kroft: but the panel's dissatisfaction was not just with social media. it was with all media, which they see as an enabler and part of the electoral process that delivered the two unpopular presidential candidates to their doorstep. >> luntz: they've now dismissed all of you for your biases, for your focus on entertainment, for this battle for ratings and profitability rather than information and knowledge. and they simply now collect information to affirm themselves rather than to inform themselves.

but when we don't even agree on the same facts, then how can we possibly agree on the same solutions? >> kroft: at one point in the focus group, frank luntz asked the participants to pick up devices he'd provided in order to track their collective responses to a series of news clips and campaign ads. >> luntz: you're going to start at zero. the more you want to vote for them, the higher you turn your dial, the less you want to vote for them, the lower you turn your dial. i want you to react second by second to every word, every phrase. is that clear? >> kroft: an overlay on the screen tracked their instantaneous responses by political affiliation. republicans in red, democrats in green. when you see the lines go down, they don't like what they're hearing. >> donald trump: i moved on her like a (no audio). but i couldn't get there. and she was married. then all of a sudden i see her, she's now got the big phony (no audio) and everything. she's totally changed her look. >> billy bush: sheesh, your girl's hot as (no audio). in the purple. >> trump: whoa! whoa! >> bush: yes!

the donald has scored. >> based on those ads, based on those clips, you can't. i mean, i can't consciously and morally vote for trump. i just can't. >> luntz: how can you? >> because hillary's worse. (overtalk) it's that simple. it's that simple. >> hillary clinton: all i can tell you is, in retrospect, if i used a government account and i had said, you know, let's release everything. let's let everybody in america see what i did for four years, we would have the same arguments. so that's all i can say. >> clinton: i-i mean, i don't... i mean, i have no idea. that's why we turned it over. >> interviewer: you said you were in charge of it. you were the official in charge of it. did you wipe the server? >> clinton: what, like with a cloth or something? no. >> luntz: that was one of the lowest dialed moments that i have done in this entire campaign. why was that so bad? >> she was laughing. she-she was, like, making fun of it. she thought it was like a joke. she didn't take it seriously. >> luntz: i feel like i'm a child of a divorce.

these two candidates, the way they fight, the way they yell at each other, the way they make it personal, it's like having your parents get divorced, and you don't want to live with either of them. and the judge sits there and says, "pick one or the other." and you say, "how about the jury? can i... can i go there?" it's awful. >> kroft: but luntz worries that voter disillusionment runs much deeper than trump and clinton. >> luntz: how many of you would say that you're mad as hell? raise your hands. it's just about everybody here. so what are you mad at? >> i'm mad at the-the corruption, the money in politics, how they appease these big investors, it's just... >> luntz: what are you mad at? >> taxes. we're paying through the nose. >> we're spending money in the wrong places. we should cut funding to the military and spend it on social programs. >> luntz: what are you mad at? >> we're not taking care of our own. veterans, people going hungry, and we're all a nation of immigrants, but people are just walking in and getting social services, not contributing to the tax base. >> they do pay taxes.

>> it's an abomination. >> kroft: you think they feel betrayed. by whom? >> luntz: they were betrayed by politicians who didn't keep their promises. they were betrayed by c.e.o.s who left them behind, who shipped jobs overseas, didn't give them the benefits that they thought they were going to get. they were betrayed by social security, which they don't believe will exist when they retire. they were betrayed by things in their day-to-day life. it's election night and i'm the losing candidate. what do you want me to say? >> "i accept the results." and to walk away and help the country move forward in the right direction. >> luntz: you lean towards trump. you've said so many times. >> yes, sir. >> luntz: do you want trump to say that the system isn't rigged? >> i want him... that's correct. it's not rigged. these are the results. get behind the new person in charge. >> luntz: what do you want the loser to say to the winner on election night? >> "i know this has been a long campaign. but at the end of the day, these are the results. and we've thrown a lot of mud over the last year and some change.

but it's time for us to move on and become better and learn from this process." >> luntz: there is still the thinnest of threads that bind us together and the willingness, in certain situations, to listen and learn. but we're one thread away from everything being cut. and that's why election night is everything. i want to know what those two candidates are going to say. please. your words have power. find words that unite. find words that unify. because if you don't, the consequences on the ninth, on the day after, will be horrific. >> this cbs sports update is brought to you by ford division. i'm james brown with scores from the nfl today. the ravens snap a four-game skid and move enter a tie with pittsburgh atop the a.f.c. north. eli manning threw four touchdown

passes. the giants get their third straight win. k.c. wins their fourth in a row. the lions stun the vikes in overtime as minnesota dropped its third straight. zach prescott leads dallas to its seventh win in a row for the first time since '07. for more sports news, go to cbssports.com. ♪ one smart choice leads to the next. ♪ the new 2017 ford fusion is here. it's the beauty of a well-made choice. ♪ thosthey are.sses? do i look smarter? yeah, a little. you're making money now, are you investing? well, i've been doing some research. let me introduce you to our broker. how much does he charge? i don't know. okay. uh, do you get your fees back if you're not happy?

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>> pelley: the presidential election may have pushed the zika virus off the front page, but zika is not going away. it's spreading. dr. jon lapook, on assignment for "60 minutes," has been tracking the zika virus, and the american government's efforts to control it. >> lapook: the first time most americans heard about the zika virus was when it was breaking out in brazil last winter. hundreds of babies were born with catastrophic brain damage called microcephaly. the question for americans has been when, not if, it would break out here. well, now it has. already, there are more than 30,000 diagnosed zika cases, most of those in the u.s. territory of puerto rico, but also in every state but alaska. and because it is now known zika can be transmitted through mosquitoes, blood and sex, that

number is expected to rise. in september, after eight months of political deadlock, congress finally approved $1.1 billion to fight the virus. dr. anthony fauci, head of infectious diseases at the national institutes of health, says the delay is an example of what worries him most about zika. >> anthony fauci: people don't take it seriously. >> lapook: how do you not take it seriously, when you see the babies with microcephaly? >> fauci: but people don't-- people don't. >> lapook: how do you explain that? >> fauci: they tend to say, "well, i'm-- i'm not seeing anything. so it must not be happening." >> lapook: it's invisible, so it's not real? >> fauci: or you-- or you don't know somebody who's had a microcephalic baby yet. yet. >> lapook: dr. anthony fauci has been on the frontlines, fighting every virus to threaten americans since the 1980s. that includes h.i.v., sars, h-1- n-1, and ebola. he says not in 30 years has a virus emerged so unexpectedly and viciously. when zika infects a pregnant woman, the toll it takes can be

horrifying. the virus can attack a fetus's brain and start eating it away, leaving newborns with small, malformed heads. when you first saw those photographs of the babies with microcephaly, what went through your head? >> fauci: you realize that the suffering that's associated with that. the suffering that that baby, if the baby does survive, what that baby has to look forward to for the rest of their life. and the impact on the family. >> lapook: the zika virus was discovered in the heart of africa in 1947 and infected small clusters of people over the next 60 years. but then, in 2007, it began popping up on some islands in the pacific. people infected there started traveling, triggering, dr. fauci says, a global pandemic. >> fauci: all of a sudden, the yap islands, french polynesia, easter island, brazil, south america, central america, puerto rico, gulf coast. i mean, that is such an example of how, when you have a transmissible agent and people travel.

and that's exactly how the infection got to florida. the mosquito didn't fly from rio de janeiro to florida. the mosquito flies 500 feet in a lifetime. it's the people who travel. >> lapook: travelers with zika have the virus in their bloodstream for about a week. when they arrive in a place without zika, a local, uninfected mosquito can bite them, become infected, and then go on to bite other people, spreading the virus. that's what happened in puerto rico, where in just over six months, zika engulfed the island, and infected thousands of pregnant women. in september, we were at the university hospital in san juan when one of them, rocio hernandez, went into labor. el corazon. >> rocio hernandez: si. >> lapook: boom, boom-- that's the heart. >> hernandez: si. >> lapook: zika infection during any trimester can cause birth defects, but research suggests early infection, in the first three months, poses the greatest

risk to the fetus. rocio was diagnosed late in her pregnancy. after 21 hours of labor, an emergency c-section. the nurses are meticulous, looking for any sign the zika virus has infiltrated the newborn's body. they take the usual height and weight, and collect samples of urine and blood for testing. head circumference is crucial. any deviation from the norm could indicate the virus has attacked the baby's brain. baby boy derek's head size looks good. but obstetrician dr. alberto de la vega is alarmed by what he's been seeing in other pregnancies. he's done prenatal sonograms on over 450 zika-positive pregnant women in the last nine months. >> alberto de la vega: you see these lines over here? this is a skull. it looks like it's collapsing and it's not growing adequately.

you see? >> lapook: so it should be something more like this? >> de la vega: it should be as having a round view. but what you're seeing is that this parts of the skull are going inward like that. >> lapook: and they're going inward because? >> de la vega: the brain is not only is not growing, but it's dying. >> lapook: how many weeks is this along? >> de la vega: this is a 20-week pregnancy. >> lapook: so what did you say to the mother here, or what did she do? >> de la vega: well in this particular case, the patient decided to terminate the pregnancy after we counseled her and told her about what we were finding. and it was a very difficult for her to make that decision. this is the head. >> lapook: the day we met dr. de la vega, he was performing a sonogram on raquel morales. she got zika early in her pregnancy, and is 24 weeks along. >> de la vega: your baby's growing normally. your baby's brain is growing proportionately and normally.

these are great news. >> lapook: but when it comes to zika, dr. de la vega says, every conversation includes a question mark. >> de la vega: there may be things we cannot detect. there's a lot about the zika virus we don't know. and we hope for the best obviously. >> lapook: right now, raquel and her baby are not out of the woods? >> de la vega: definitely not. no one is. no one is. we only know about the more severe consequences. how about all the other problems that could arise? is this baby going to have autism? is this baby going to have learning disabilities? is he going to have cerebral palsy? we don't know. >> lapook: there's probably going to be a spectrum of disease? >> de la vega: which we are far from describing. >> lapook: doctors are finding that in addition to microcephaly, babies can suffer other developmental problems-- inability to swallow, seizures, hearing loss and damage to the retina, which can lead to blindness. would you recommend that women

not get pregnant? >> de la vega: definitely. until we have a vaccine, or until we have control over this epidemic, you should avoid it. this is not the time to get pregnant in puerto rico or any place where the infection is occurring. >> lapook: according to the centers for disease control, there are now more than 1,000 pregnant women on the united states mainland who've been infected with zika, most through travel. 25 babies have been born with microcephaly or other birth defects. five pregnancies have ended with the loss of the fetus. the united states government is not recommending that women delay pregnancy. it has largely focused on killing the mosquitoes that carry the virus. but that may not be enough. zika has stunned scientists by becoming the first mosquito- borne virus ever known to be transmitted through sex. is it possible that a lot of the infections, that we were

ascribing to mosquitoes, were really sexual transmission? >> fauci: well, i think that's an open question, that we need to address and find out. just how frequently is sexual transmission occurring? how much of it are we missing? how long does it remain in the semen? because that's a real complicating issue, particularly since 80% of infections are without symptoms. someone could be infected and have absolutely no idea that they're infected. >> lapook: for those people who do get symptoms, zika usually resembles a mild flu-- fever, muscle aches and a rash, often subtle. but in some adults, the virus can cause severe neurological problems. in puerto rico, we met this man, who after being bitten by a zika-infected mosquito, suffered inflammation of the spinal cord, leaving him barely able to walk. his doctor is not certain he will recover. last winter, when the epidemic hit, dr. fauci knew the best way to stop zika was to develop a vaccine. >> fauci: we had an, "okay, all

hands on deck" type of meeting. "let's do it. we've got to do it." >> lapook: dr. fauci and his team had a head start. he showed us how a vaccine they'd already created for west nile virus was re-configured for zika. >> fauci: this is what's called a d.n.a. platform. and a d.n.a. platform is made up of a plasmid, which is merely a circular piece of d.n.a., and what it has in it, is an area where you can actually insert the gene of whatever virus you want to make a vaccine against. so, we just stick in this gene from zika. and now you have a zika vaccine, merely by replacing this little segment. >> lapook: kind of like a prefabricated scaffolding, right? >> fauci: the foundation stays the same. you put in the part. if the part is west nile, you stick the west nile in. you want to do zika? you take the west nile out. you put zika in. >> lapook: the d.n.a. in vaccines like this can be quickly mass produced.

this new approach means future vaccines could take months, not years, to reach clinical trials. >> fauci: hey catherine. >> catherine paquette: good morning. >> lapook: last august, we watched with dr. fauci as volunteer catherine paquette received the very first dose. this experimental vaccine does not contain live virus, so it cannot give her zika. >> one, two, three. >> lapook: a month later, catherine's blood was collected to see if the vaccine was generating the expected immune response. it's turning blue. >> fauci: how about that? that's what's called instant gratification. >> lapook: the blue color indicates the presence of antibodies programmed to fight zika. >> fauci: we know that this kind of antibody protects an animal. so you can make a reasonable extrapolation that if you make the same kind of response in a human, that you will ultimately protect the human. and that's exactly what this is showing. >> lapook: that's is a big moment. if that had not turned color... >> fauci: if that had not turned color? >> lapook: then what?

>> fauci: i would of fainted in front of you. >> lapook: they plan to soon test the vaccine in thousands of volunteers living in zika- infected areas like puerto rico. if it protects people there, it could be ready for distribution by early 2018. by that time, millions of people around the world will already have been infected. one of the big questions i've been hearing is, say, for example, "my ten-year-old daughter, if she gets infected now, will she have a problem ten years from now, when she gets pregnant?" >> fauci: there is no indication that there is going to be a problem at all. however, you always keep your eye out to see if there's something that we haven't noticed. >> lapook: staying alert, dr. fauci says, is key with all infectious diseases. back in the 1980s, when h.i.v. emerged, he started keeping a map to track the threats. >> fauci: so this was the first one that i did in 1984, and this is the last one. >> lapook: oh my gosh.

>> fauci: so these are all things that have emerged, you know? everything from lyme disease, through anthrax, through chikungunya. now we got zika, was the most recent one that was added. we have ebola right here in west africa. >> lapook: if one of these broke loose, really broke loose, it could kill how many? >> fauci: god forbid if you ever had a flu that transmitted very easily and had a high degree of mortality, you could have a really serious situation. >> lapook: like tens of millions of people? >> fauci: more than that, yeah. >> lapook: dr. tom frieden is responsible for making sure that doesn't happen. he's director of the centers for disease control. how many warehouses like this are there? >> tom frieden: i can't tell you that. but we have them distributed such that we can reach any part of the u.s. within 12 hours or less. >> lapook: they are called strategic national stockpiles, and our "60 minutes" cameras were given a rare look inside one of the secret facilities. >> frieden: if there were a big outbreak, we have medical supplies-- vaccines, antibiotics, intravenous fluids.

things that would be needed to keep people alive and protect them. >> lapook: dr. frieden is eager for a zika vaccine to add to the arsenal. until then, the c.d.c. is deploying hundreds of scientists and public health workers to promote mosquito control, raise awareness about prevention, and develop new ways of testing for the virus. you recently wrote that zika presents an unprecedented threat to our nation. >> frieden: zika really is unprecedented. never before have we seen a mosquito-borne virus that can cause birth defects. >> lapook: what happens at the end of this mosquito season? >> frieden: mosquitoes usually quiet down around the end of october, longer in puerto rico and other places, but next season isn't far away. and we anticipate that zika is likely to be with us for years to come.

>> is zika coming soon to a mosquito near you? a conversation with dr. jon lapook at 60minutesovertime.com. ♪sitting in the sunshine by the trees♪ ♪pretty little love birds sing to me♪ ♪they don't got a care, just a melody, yeah, yeah♪ burt's bees lipstick.

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>> pelley: in the mail this week: comments about our story on "the pot vote." dr. jon lapook examined the highs and lows of colorado's experiment legalizing recreational marijuana. "i was disappointed you didn't compare legalized recreational marijuana to legalized medical marijuana.

you covered recreational use problems, but didn't contrast medical use benefits." pat desocio, glen cove, new york. there was nothing very mellow about some responses. we've deleted a few expletives in this one: "maybe we should drink and take pills you (no audio)! some viewers questioned our vocabulary. i'm scott pelley. we'll be back next week with another edition of 60 minutes. and join us tuesday for live election coverage all through the night right here on cbs.

carcharodon carcharias, aka the great white shark. here's the liver. huge, isn't it? it's fatty, used for buoyancy, because sharks don't have swim bladders. here's the stomach. help me pull it out. it can expand to fit whatever the shark eats, which can literally can be anything from... (grunts) other sharks to old tires. that looks like a face. that's bizarre. let's have a look.