dr. john torres, nbc >>> still ahead tonight, beating the odds. the american boxer out to make olympic history a second time. the barriers she punched through to become queen of the ring. >>> also, simone's surprise, we're there when she and her final five teammates get a visit from her hollywood >>> back now from rio with a story about a young woman who overcame the odds and punched her way to olympic gold four years ago in london at just 17. american boxer looking to put a one-two combination together. we dared to get in the ring with her but just to check. >> reporter: overcoming the tough streets of flint takes a fighter's mentality, survivor's will. >> i live right over here. >> reporter: something claressa shields learned the hardware, her dad in prison much of her childhood and her mom overcoming alcohol, she put up her dukes. it landed her here a short time way but at a boxing gym. >> it's taken you a long way from here? >> it has. to hit back at life and chance to punch her ticket out and a chance to make her father proud. he had told her

dr. john torres, nbc news, new york. >>> still ahead tonight, beating the to make olympic history a second time. the barriers she pun punched through to become queen of the ring. >>> also, simone's surprise, we're there when she and her final five teammates get a at safelite, we know how busy life can be. these kids were headed to their first dance recital... ...when their windshield got cracked... ...but they couldn't miss the show. so dad went to the new safelite-dot-com. and in just a few clicks, he scheduled a replacement... ...before the girls even took the stage. safelite-dot-com is the fast, easy way to schedule service anywhere in america! you don't have to miss a thing. y'all did wonderful! that's another safelite advantage. (girls sing) safelite repair, safelite replace. h. heartburn. sorry ma'am. no burning here. try new alka-seltzer heartburn relief gummies. they don't taste chalky and work fast. mmmm. incredible. can i try? she doesn't have heartburn. new alka seltzer heartburn relief gummies. >>> back now from rio with a story about a young woman who overcame the odds and pun

dr. john torres explains, tens of thousands could be spared painful surgery and treatment. told two years ago she had thyroid cancer. it may seem hard to believe, even risky, but she and her doctor decided not to treat it for now. >> because it's so slow growing, i figured it can't hurt to do the watchful observation and see what happens. >> reporter: that's the approach a report in today's new england journal of medicine suggests may be best. researchers found doctors overdiagnosed thyroid cancer about 80% of the time because new screening up small growths that are slow growing and unlikely to cause symptoms or death. what happens to these lesions if nothing is done? >> the vast majority of patients don't need treatment for these small thyroid cancers. >> reporter: most often diagnosed in women, thyroid cancer treatments can be harsh involing surgery, radiation and medication for life. because megan's cancer was small, her doctor at mount sinai hoit careful monitoring knowing if it starts to grow, it's still treatable. >> they know they have the option to do surgery any ti

dr. john torres joining us now. some people may not even know they have it. >> you're right. the vast majority of people, they could get affected by this and not know they have west nile. here's how symptoms break down. again the majority of people, a little under the weather. you have 15 to 20% with more moderate symptoms, body aches, joint pains, rashes, headaches, might get nausea and vomiting, but they recover. here's the one. for less than 1% of people they can develop neurological issues. those are tremors, seizures, weakness in the arm or leg. that can become permanent develop neurological symptoms are also the ones most likely to die from west mile virus. we've been hearing about zika the last several months. this is the one we need to worry about in west nile. our peak west nile season is usually late august, early september and into fall. pay particular attention to evening. all day long use mosquito repellant, wear long sleeves, shirts and pants and protect yourselves and your family from the mosquitoes. >> can't stress that enough, especially this time of year. >>

dr. john torres. ally torres and her proud dad are here. so nice to meet you. >> so glad i could be here. >> so exciting. you guys got a good gene pool because because your brother and now you. >> right. >> what made you say this is it, this is my field? >> honestly a lot of it was growing up watching my dad. i was a kid when he was going through medical education, so i getting into. i don't like to admit it, but he's kind of a hero of mine. >> to us, too but we don't like to admit it. >> you any you kind of know what -- think you kind of know what you're interested in? >> i want to go into e.r. right now. that will probably change a couple times. >> because you don't like reasonable hours? >> obviously. >> i think it sounds like exciting work and you can do a lot with it, especially disaster medicine. >> and that's true. most people when they go to medical school, they change multiple times because you do rotations your third year and gets a taste of everything and you find out the things you're good at or don't like as much, so it's good.

dr. john torres joins me now. drvmt torres, first, this is outside the zone.ard about this zone and it's contained within that, but that's not the case. >> that's not the case right now. that's why we're serious about this and concerned about what's going on because what's happened is up until now, it's been on the atlantic side of florida. the miami area. well now jumped over to the golf side of florida. that's a huge distance there. mosquitos cannot travel that far. we know that that's happened because people have had zika virus and mosquitos locally have probably bit them and transmitted to somebody else which is thousand spreads. this is not a mosquito flying from one side of florida to the other, people with the infection bringing it there and mosquitos biting them and then spreading it. >> are you surprised it hasn't spread faster, given what a massive threat this is. even just one case in a different zone. it's not like it's in another state. >> to a certain extent i am, the big thing right now, it's a very small world and we're traveling a lot more. pe

john torres is joining us live from new york. hi dr. john, how are you? >> i'm doing great, kim. >> as always, hepatitis a, it affects the liver right? >> it all the hepatitises affect the liver. there's a variety of them. in this case, a, exactly what happens here, it comes from a contaminated food. a food worker comes in, doesn't wash their hands well, and spread that to the food. the concerning thing, especially for colorado, it has the incubation period of up to 50 days. happening. >> let's say you have been to one of these places. what do you do? is there anything you can do to prevent it? probably not. >> listen to the news. if you find out in it's colorado, you want to talk to your doctor about it. do you need an immunization for hepatitis a. if someone is in their 30s or 40s, they likely didn't get the immunization. you are affected by this hepatitis a, if you're one of the people that allot the contaminated food, that can make sure you don't get the symptoms or that they don't last long. for most people, the symptoms are going to get nausea, bell