this is "nightline." >> tonight, as america nears a grim milestone, 100,000 people dead from covid-19. a diane sawyer special report shows us how we got here. a nearly three-months-long investigation examining everything from the hidden ways the virus spread to the front line workers risking it all. plus, our new reality, finding a path forward on the pandemic. the newest science on vaccines, and wearing a mask, and how a call for help became a beacon of hope. >> "nightline" starts right now. >> good evening, thank you for joining us. i'm diane macedo. nearly 100,000 people, mothers, fathers, brothers, sisters, daughters and sons, all connected to a single killer. covid-19.

america is now approaching 100,000 deaths. people like jerome rice from elisabeth, new jersey, a marine corps sergeant in the korean war. he loved listening to music like jimmy buffett and abba. he was 86. mary santiago of evanston, illinois, she died weeks before seeing her oldest son graduate high school. and schuyler herbert of detroit. the daughter of two first responders. she had dreams of becoming a pediatric dentist. schuyler was just 5 years old. and now how we got to this pandemic and the way forward. here's diane sawyer with her special report. >> three, two, one! happy new year! >> reporter: there we were on new year's eve. americans living in the most vibrant country on earth, celebrating our lives with careless kisses and laughter. not even thinking about how

wonderful it is to reach for the hand of a stranger or whisper a secret. and we didn't know that on that very night, the government of china had told the world health organization that a mysterious new disease was on the move, through wuhan. january 21st, we learned about the first diagnosed case of the virus in america. a man, only in his 30s in washington state. but he had just come from a trip to wuhan. and wuhan was so far away. >> one person, coming in from china. and we have it under control. it's going to be just fine. >> reporter: president trump moves quickly to ban all travelers from china, except for americans and their families. as two months go by, no one prevents 2 million travelers from continuing to pour into this country from europe and stream out across the nation, some of them taking the virus with them to places we'd least expected. places like the beautiful ski

resort of sun valley, idaho, which would become one of the highest infection rates in the entire world. it is the first week of march, and no one is even talking about social distancing, when the permanent residents of the valley welcomed the last ski-loving tourists of the season. a lot of them are coming from the west coast like seattle and from europe. >> my name is jodi, i live in idaho. >> reporter: who lives here? >> everybody lives here. it's a great cross section of families and retirees and kids. your quintessential small town. oh, and there's also the millionaires. >> reporter: and there may have been something else making its way through sun valley, brent russell is an er doctor there. >> the last week in february most of our skiers from seattle, seattle is a hot spot at that point. >> reporter: but none of the skiers at that point knew that. everyone hits the slopes and gathers shoulder to shoulder with locals for after-ski parties. >> they were up on credenzas,

tables. >> reporter: a local project manager at a construction company goes to an after-ski party. it's so crowded. >> there had to be at least 700 people. >> reporter: again, that was friday the 6th. three days later. >> i had one sneeze, and it was one of those sneezes like you're oh, something's coming. and the next morning every part of my body hurt. >> reporter: she gets tested, the test comes back positive for the new virus. >> 35 people, 40 people. >> reporter: her friend jodi had been at the party, and she and her husband and daughter are getting sick, too. >> when i was getting tested, i talked to one of the nurses about my friend be being the first person with coronavirus. and she shook her head and said that's absolutely wrong. we've been seeing a mysterious respiratory illness for the last six weeks.

>> reporter: and one group of skiers who traveled into sun valley is about to suffer the biggest toll, the national brotherhood of skiers, coming into town for their annual summit. they are some of the best african-american ski clubs in the country, the goal to get one of the members on the olympic team. after they ski the mountains and head home the nightmare begins, fever, collapsing in the bathroom, strug arealigling to , racing to the er. mike tolliver has flown back home to pompano beach, florida, his wife stephanie, a wellness advocate. >> i called urgent care. they said we have no test and we can't help you. click. we called primary care. they said if you get really ill call 911. i called the er. they said you better call the health department. everything was like a "we can't help you." >> reporter: she finally said to the doctors at the hospital, you have to help me. you have to help me.

>> i said we aren't leaving until he gets tested. >> reporter: he was positive. and all told, after their ski trip to sun valley, out of 600 brotherhood skiers, 126 got sick. at least four members have died. back in idaho, the virus has already carpet bombed the small community hospital. >> i got high fever, shaking, chills. >> reporter: again, dr. russell. >> we didn't have enough people to keep going. seven full-time emergency room doctors and five have been out. >> reporter: in the first week of march, clusters of cases popping up across the country. as we look back from this distance, we learn something we will now know forever. one brush fire of virus in this nation is a warning to us all. and then, in the second week of march, americans begin to understand that it is in fact too late to contain the virus. >> today i am officially declaring a national emergency. two very big words.

>> reporter: by march 17, the virus now in 50 states. to stay safe and try to save lives, americans are told the best option is to go behind doors, stay home. this giant nation in a sense shutting down. the nation locked in time. it's the moment in any movie when you wonder if the cavalry will come. and it did. and it was us. >> i'm puttin' my life on the line every day. >> as long as i'm healthy, we are going to keep going. >> all right, good morning, good morning. about to get ready to get my bus started. >> reporter: this is bus driver eric holts of detroit who showed up every day even though his best friend was a bus driver named jason hargrove. hargrove was one of the first

people to go public about people who didn't show respect. >> for you to get on the bus and cough, that lets me know that some folks don't care. >> reporter: two weeks later, he had contracted the virus and died. he left behind a hash tag. i cannot stay home, i'm on the road for you. >> it's a hard day for me today. we will be doing the final arrangements for my best friend, jason hargroves. >> reporter: eric keeps going, some days working a double shift. i dialed in to him before his overnight. can you show me what it is to get on the bus and wipe things down? >> this one comes off the steering wheel. >> reporter: whoa. how many people are getting on the bus now without masks? >> you have that 58% that just don't want to wear the mask at all. >> reporter: eric became a virus detective. he feared that coughs or sneezes might be carried by the air conditioning draft straight to him. >> so what i do, is i do not run that ventilation system. >> reporter: at the end of his long day, he takes his clothes off, making sure to wash them.

afraid for his family. and he shows me the empty seat on his bus where he imagines his best friend jason is still sitting and talking and watching over him. >> and just again, be safe. because somebody you haven't talked to in a while, call them up, tell them you just love them. >> reporter: and, as the months went by, we all watched something so clear about a divide in america. 55% of us got to stay home. had jobs and salaries. we got our deliveries at the door. but the lowest-paid workers in this nation, often without medical coverage or sick leave, were showing up. they were scrubbing every inch of our grocery stores and taking risks. so many of them minorities. workers like angel, who's worked all her life in fast food and cleaning as a home health aide. and this is her budget. at the end of the month, she's lucky to have $18 to spare. her three children make their own hand sanitizer.

they make their own masks, and she never wants them to be homeless like she was as a child after her mother died. >> and i want my kids to have stability. >> reporter: she says she's so grateful that in this moment some cities and philanthropies decided to offer free child care to essential workers. new york city alone has 172 facilities. >> my dad is an airplane de-icer, a school bus driver. >> my mom's a police officer. >> my mom is a home nurse. >> i'm gonna be brave. i'm super maabci distancing, so i'm going to try to let the coronavirus be over by washing our hands, yeah! >> reporter: and maybe in the years ahead, we will teach our children in a new way about the lives of the workers who never flagged. the people we lost in just four

months. there can never be just one tribute to them all. when we come back, the race for a vaccine and what science now says about wearing masks and how one woman in a windowless restaurant infected so many others. windowless restaurant fikted restaurant infected so many others. it has three times the cleaning power of the leading spray to dissolve kitchen grease on contact. and it's great for bathrooms! just keep pumping the power nozzle to release a continuous burst of mist and make quick work of big jobs. it even works on stainless steel. it cuts through 100% of dirt, grease and grime. available with easy-to-swap refills. to get three times the cleaning power, try clean freak from mr. clean. frto baking fails...inters...

to sweat sessions. even life inside can bring on things like sweat and oil. but it's nothing a deep clean can't fix. love, neutrogena®. a breakthrough 10 years in the makingveclear, that reduces allergens in cat hair and dander. outstanding nutrition with the power to change lives. this is purina pro plan liveclear. so here's to the strong,

who trust in our performance and comfortable, long-lasting protection. because your strength is supported by ours. depend. the only thing stronger than us, is you. try nature's bounty sleep3, because your strength is supported by ours. a unique tri-layer supplement that calms you, helps you fall asleep faster and stay asleep longer great sleep comes naturally with sleep3. only from nature's bounty. brushing only reaches 25% of your mouth. listerine® cleans virtually 100%. helping to prevent gum disease and bad breath. never settle for 25%. always go for 100. bring out the bold™

when visible set out to create the future of phone service... we tossed the stuff that wasn't working.

and kept the stuff that was working. like verizon's 4g lte network. meet visible. unlimited data, messages and minutes. just $25 for your first month. join us at visible.com.

as of tonight, the whole world is in a fierce fight against the virus, and think of these people as our jedi warriors, mobilized, ready to take action. i've been talking to dozens of scientists who are staying up all night in their labs trying to find the treatment and vaccine. >> this is an assault on humanity. >> around the clock, seven days a week for our patients that are trusting us. >> what do i need to do next that can help our country get through this crisis? >> reporter: one scientist,

this doctor, called in a team. analyzing 7,000 studies, 18,000 patients, 161 treatments, to find out which ones are starting to work. he skips meals, steals a few minutes with his daughter in his office and shares his findings with everyone. and since we know the holy grail is a vaccine that prevents people from getting the illness, how fast can it happen? keep in mind, in history, the fastest time from identifying a virus to having a vaccine has been years. it took four years for mumps. as of tonight, scientists are trying to do it in a fraction of the time. and, as we know, until there's a safe vaccine, we only have our primitive tools to prevent contracting the virus. the first, of course, social distancing. we have now learned that 35% of people who could be spreading the virus may display no symptoms at all, which is a reason we're told to stay at least six feet away. but, if someone decides to sneeze, what good does six feet

do you? a cloud of particles, which may or may not contain the virus could spread as far as 26 feet. and we saw that chinese study of a woman with no symptoms at a crowded restaurant with no windows. she spread the virus to nine people around her, as far as 15 feet away. droplets in her breath, possibly carried by the slip stream of the air conditioner. and over the months, so much confusion about masks. >> you can increase your risk of getting it by wearing a mask. i wear my face covering to protect you, and you wear yours to protect me. >> reporter: and if you still don't think a mask could make a difference, take a look at this video. this is how much we spray saliva at each other in our every day conversations. >> stay healthy! >> reporter: put a mask on, that spray is dramatically different. >> stay healthy! >> reporter: here it is again, without the mask.

>> stay healthy. stay healthy. stay healthy. >> reporter: and right now, there are two types of treatments that have shown real promise, but both are administered through ivs, and both are for patients in the hospital. one is remdesivir, and then there are the anti-bodies that appear in someone who has fought off the disease. someone who has recovered gives blood. it's separated into plasma. think of it as liquid gold with antibodies in it. in as little as three weeks, one company already making anti-bodies in their lab will begin testing, to see if their anti-bodies can prevent or treat covid, but once again, it's all of us now heeding the call for each other. it started in the amazing lab of dr. florian cramer and his team in mt. sinai. >> and so you can see that some of these wells change color. >> reporter: they identified

those golden antibodies. and the headline tonight is that plasma does seem to work in some patients. >> we want to see if these can neutralize or block the virus. >> reporter: we tracked down the first person in new york who was asked to be a plasma donor, tiffany, a single mom who works with the homeless. i think you are a superwoman. >> thank you, i am truly humbled by this experience. we all kind of need each other right now. i just pray this works. >> reporter: we now know the patient she donated to is doing well. >> it was not painful at all. and i would definitely recommend or encourage anyone who had the coronavirus and has beat it to go and volunteer to give your blood, to see if you can potentially help people. >> reporter: and across the country, thousands of others have stepped up to donate, like this man, james crocker, who recovered from covid and saw a prayerful post on the internet

about a patient in big trouble. so crocker got in his car and drove two hours to the one blood donation center in florida, to see if he qualified to help that stranger in the icu. he donated. he was a match. and four days later, something happened in that hospital room. >> love you, dad. >> come on home, baby. >> love you, daddy! >> he's crying? oh, baby, i see you. i see you. >> reporter: after 19 days in the hospital, that patient, kevin, came home. friends and neighbors waiting for him, and his plasma donor, too. >> one day, two days, five days, it can make the difference. >> reporter: and so this is how we will go through it all. doing our best every choice a mix of uncertainty and hope. helping each other. and discovering our strength together. one step at a time.

we'll be right back with a final note. >> whee we'll be right back with a final note. choices. many dealers now offer optional pick-up & delivery and at-home maintenance, as well as online shopping with home delivery and special finance arrangements. so, whether you visit your local dealer or prefer the comfort of home you can count on the very highest level of service. get 0% apr financing up to 36 months on most models, and 90-day first-payment deferral on any model. chances are you have some qhere are a couple answers... lysol disinfectant spray and lysol disinfecting wipes together can be used on over 100 surfaces. and kill up to 99.9% of germs. lysol. what it takes to protect.

try nature's bounty sleep3, a unique tri-layer supplement that calms you, helps you fall asleep faster and stay asleep longer great sleep comes naturally with sleep3. only from nature's bounty. you wof your daily routine, so why treat your mouth any differently? complete the job with listerine® help prevent plaque, early gum disease, bad breath and kill up to 99.9% of germs. listerine® bring out the bold™ chances are you have some qhere are a couple answers... lysol disinfectant spray and lysol disinfecting wipes

together can be used on over 100 surfaces. and kill up to 99.9% of germs. lysol. what it takes to protect.

finally tonight, as we remember the nearly 100,000 americans lost in the pandemic, we leave you with the story of dr. james anthony mahoney of brooklyn, new york. friends and family called him charlie. he was set to retire but kept serving two hospitals, dr. mahoney was 62, one of almost 100,000 lost. that's "nightline." goodnight, america, be safe. "nightline." fo goodnight, america, be safe. ♪ ba, da, ba, da, ba, da, ba, da, ba, da, ba, da, ba, da ♪ ♪ jimmy kimmel live this is ridiculous, from his house. >> jimmy: hello. i'm jimmy kimmel and welcome to the opposite of a spin class. thank you for being with me, even if it's because you literally have nowhere else to go.

i hope you had a pleasant memorial day. we spent the long weekend trying to put the duvet cover back on the bed. fun. this was a weird memorial day. i think we can all agree that zoom barbecues suck. this weekend, donald trump, by unauthorized presidential order, made a sweeping declaration to open all churches, temples and places of worship in an effort to make sure the most devout americans get a chance to contract the coronavirus too. it was a controversial decision, one that could endanger the lives of many, but anyone who knows donald trump knows that he is a man of great faith. and so on sunday morning -- he went to church. for the first time. he went to -- wait, that's not church. he went to golf? he went to play golf during the pandemic, because that's what jesus would do? i guess. i don't know trump thinks he's at the u.s. open while the u.s. is closed. and, you know, people say he's unfit to be president.