crash. >> all right, thank you everybody. rememb remember, the bluefin-21 will come back up, let's hope it is working properly so it can stay down the entire 12 hours. that is it for me, a sonar sub in the flight 370 back on track. you'll see what a bluefin-21 can see. also breaking, new video. what appears to be the largest most dangerous gathering of al qaeda in years. did the cia and pentagon know about it or not. later, our dr. sanjay gupta fighting to stop the ebola crisis in west africa. some of those medical personnel have lost their lives in the battle. we begin with the latest for nearly three miles deep. first full day. expected to be the first day on

the job. as you know yesterday's mission was aborted after six hours. today's dive is expected to go around the clock. there are new developments on that front, new developments, as well, with that oily substance recovered from the ocean surface and we'll also tell you about a tracking system for planes that's being rolled out over the next six years that may have changed everything about that happened to flight 370. the question is why six years from now will it be rolled out? what is taking so long. first michael holmes in perth on today's search efforts. what's the latest, michael? >> reporter: anderson, good morning from perth. the bluefin-21 down doing its work at the moment. by our calculations it is almost exactly halfway through the ocean floor segment of that. as we know, it takes two hours to get down and 16 hours on the bottom and two hours to get up and then they download the data. also, planes and ships out there again today. we had been told that that phase of things looking for surface wreckage would be scaled down this week. but no sign of that yet. they are still in the air and on the ocean looking for any wreckage. of course, none found so far.

we're now in to our sixth week. andersson anderson. >> none found so far. the data, has it been processed from the bluefin's first dive which was called off because of unexpected depth that it suddenly faced. do you know, did they find anything of note? >> yeah, good question. in fact, only in the last hour, anderson, we did get word about that. it covered about four square miles during that aborted mission. on a normal mission, it would cover about 15 1/2 square miles or 40 square kilometers. they did analyze that data and sad to say they found absolutely nothing of any use, nothing relevant. but, of course, it was just the first mission and an aborted one at that and this is a huge area they are covering. anderson? >> also the fuel recovered from the search, do they know, is it related to the plane? have they been able to determine that yet? >> not yet, no. we have to remember, that search

area is about over 2,000 kilometers off the coast of western australia. they did pick up the two liters of oil that they found floating out there near where the ocean shield is. they bottled that. what they have to basically do is get a ship out there and then helicopter it to that ship. the ship can get it closer in and then the helicopter will take off again to get it here to perth. they said it would take two or three days. so in a day or so, we will know what that is. they have sent samples actually of the engine oil that would have been in mh-370's engines so that they can do a comparative analysis on that. they are also going to check to see whether if it could be hydraulic fluid, as well. still unanswered questions. even just getting that back here is a bit of a journey, anderson. >> all right, michael holmes, appreciate the update. i want to bring in the panel, cnn safety analyst, david soucie, author of "why planes crash" and director special

projects, the oceanographic institution and mary schiavo who currently represents accident victims and their families. david gallo, the fact they did not get any data from the bluefin, i don't think you would be that surprised. >> they got data, it's just they didn't see anything -- this is all very typical of the first days of an expedition like this. and it's unfortunate and it's frustrating, especially to the uninitiated that something went wrong but it's not unusual. >> the fact that the mission was aborted because of the depth, they found themselves in deeper water than anticipated. the surface, it was too deep and had to call it back and recalibrate things. is that going to happen more and more? does that indicate a lack of understanding of what the depth is? >> every day they go out there they are going to learn something new about the terrain and will make adjustments to the

hardware, software, the vehicle and operations plan. it may happen once or twice more. in the air france 447 we had a lot of aborted runs from our robots but you learn. the team is capable so they will learn. >> why not have more than one bluefin out there? air france you had three vehicles. >> we had three -- well, i think because their approach is different. they are going, as captain matthews talked about this tactical approach. they have a solid pinger location and will throw the dart at the bull's eye. our idea was to pick an area that's much larger than the search area and do the entire area. cover it with multiple vehicles. it was a totally different mapping program. >> david, do you think that indicates perhaps they have more information than they are letting on? >> that's the way i'm seeing it. apparently they have a lot of confidence in where it is or they would have more, like david gallo said, more to throw at the target instead of a mass screening of the area. so it does indicate that to me. >> the navy has said they do, david, have another underwater vehicle that can go deeper.

>> yeah. they've got plenty of tools in the aquiver that they can bring to bear in this. if they need to change strategy, maybe this tactical means is not working they will bring something else in on the mission. >> mary, we heard from the air marshal, angus houston, the air search is nearing its end. that's certainly not something that the families would want to hear. >> well, that's true. but at some point the currents have now worked their will on any debris that might have been on the surface for five, almost six weeks, and there's just not a real chance they are going to find much at this point, this far out, it would be so far dissipated and can't justify it. particularly if, as the other guests have said, they really believe they have zeroed in on the point where the plane is. and there, of course, always the many stories that float around about australia's, you know, incredible radar, almost mythical qualities, i guess.

so perhaps they have additional information but they are throwing the dart at the dart board right where they think the bull's eye is. >> it is amazing a plane theoretically can hit the water and no debris be found. i mean i guess there was that ship that went down -- >> the "sydney." >> the "sydney" which went down and only a life raft was found. >> i believe it was years later on christmas island, thousands of miles north of the site one life raft showed up. >> incredible. >> absolutely incredible. >> we heard the malaysian transportation minister, david souci, say it matters less who takes control of the black boxes as long as the black boxes are found. to you does it matter who takes control? >> that was disturbing to me to hear that. it really doesn't matter who takes control. it matters a great deal and he's in charge of this investigation. by rules, nothing goes anywhere until he says it goes there. he is responsible for the decision. if anybody i would think he cares.

>> mary, we also heard the malaysians say they are setting up a committee to look into how a plane could have vanished without hardly a trace. is that what should be happening at this point? >> well, that plus more. when we do an investigation, when the ntsb does an investigation, they set up similar committees except far more. so it's good that they are setting up committees to investigate, but the true investigative committee that should be working overall to solve this accident, the causes, the probable causes, any recommendations, the full panoply of what comes out after a crash should contain far more working groups and committees. but, yes, if they're going to be objective and look at how this happened and look at their own response or lack thereof it is good they do that. >> and multiple fronts to work on. a lot to cover tonight including underwater territory no one has seen before and also putin's assessment of ukraine to pave the way for russian tanks which might pave the way for civil war. let us know what you think

coming up next, david gallo shows an amazing look at what the ocean floor looks like to underwater sonar devices, the bluefin-21 and the remarkable pictures these things can take. and later this day. >> mayday, we're going down. >> we will show you what begins as a disaster becomes an opportunity. air crashes over the years that have made air crashes today so rare. lessons that have been learned and what's being learned this time as we continue. [ male announcer ] this is karen and jeremiah. they don't know it yet, but they're gonna fall in love, get married, have a couple of kids, [ children laughing ] move to the country, and live a long, happy life together where they almost never fight about money. [ dog barks ] because right after they get married,

they'll find some financial folks who will talk to them about preparing early for retirement and be able to focus on other things, like each other, which isn't rocket science. it's just common sense. from td ameritrade. marge: you know, there's a more enjoyable way to get your fiber. try phillips fiber good gummies. they're delicious, and an excellent source of fiber to help support regularity. wife: mmmm husband: these are good! marge: the tasty side of fiber. from phillips. that's why i got a new windows 2 in 1. it has exactly what i need for half of what i thought i'd pay. and i don't need to be online for it to work. it runs office, so i can do schedules and budgets and even menu changes. but it's fun, too -- with touch, and tons of great apps for stuff like music, 'cause a good playlist is good for business. i need the boss's signature for this. i'm the boss. ♪ honestly ♪ i wanna see you be brave

but i didn't always watch out for myself. with so much noise about health care, i tuned it all out. with unitedhealthcare, i get information that matters... my individual health profile, not random statistics. they even reward me for addressing my health risks. so i'm doing fine... but she's still gonna give me a heart attack. innovations that work for you. that's health in numbers. unitedhealthcare.

co: until you're sure you do.you need a hotel room bartender: thanks, captain obvious. co: which is why i put the hotels.com mobile app on my mobile phone. anyone need a coupon? i don't.

underwater search teams will get a better chance of finding pieces of flight 370 and a better look at the lay of the land on the ocean floor, the nooks, crannies, hills and mountains down there. back with me now is david gallo. so we have here an image, a sonar image. this is clearly two ships. what are the different colors, is it different depths? >> the more i look at this, you are looking at different depths and it looks like maybe the blue is the shallowest. this looks like a mast sticking up inside here. >> this would be a mast here. >> right. this is the image that bluefin can take of objects on the sea

floor. >> it's just remarkable to see it like this. can you get this in one pass? or does it need multiple passes? >> it depends how close the vehicle is to the bottom or how high and big the area is but it could be one pass or multiple passes. >> i want to look at another image from a side-scanning sonar. this is a close-up of one ship. >> this is fantastic. this is the path of the vehicle. so the robot is heading in this direction, sending out pings to either side like this and the sound comes off and bounces off objects. when you see that, it is a hard return. a shadow behind it. this is a ship sitting on the bottom and you can see it went over the top of the ship. it does leave a gap directly beneath the vehicle. why they call it a side scan or a side-looking sonar. >> when you get an image like this, it is actually two images with the center where the vehicle s >> it is two beams on either side of the vehicle. exactly. a port side and a starboard side. >> i want to look at an image, not from a bluefin but one you were involved with.

wide shot under water of the "titanic." >> "titanic" split in two. looking at a mile across. these lines here are the path of our vehicles, back and forth, mowing the lawn or plowing. >> i see. you can actually see lines in the image itself. >> exactly right. so many, many images. that's over a mile across. that's the bow of the "titanic" sitting here. it broke in half. this is the stern of the "titanic." 600 meters away so six football fields away. and all this is a debris field. this is the kind of thing when you're looking for an aircraft on the bottom, all these things inside here, everything from pieces of pottery and lights. >> all of this. >> all this stuff, all of these speckles and bigger pieces inside of here. >> so the "titanic" had a wide debris field. >> it did. the stern especially. the bow not so much. the "titanic" had a huge debris field associated with it. >> there's another titanic image here. >> zooming in on the bow. it shows you how powerful sonar can be. >> incredible. >> this is one pass along the

bow, and this is the pointy end where jack was king of the world, the mast, some of the openings here. >> you can get this from one pass. >> just one pass, yep. and sometimes we go over it two or three times to make sure we don't miss anything. >> what kind of a vehicle took this? >> this is the rema 6,000. we used two of them. it is very similar to the type of vehicle the bluefin-21 is. >> does it go deeper -- >> it is made for deeper water work. >> incredible. one other image of "titanic" again. this is extraordinary. >> this is actually an optical image. many, many. you can see the size of one image right here. >> oh, so this is multiple photographs. >> this is done with a remora which is another vehicle operated by phoenix international that may or may not come into play in the malaysian air search. so this is the optical view of the same bow. >> that's an underwater vehicle that takes multiple -- >> it goes alongside the ship click, click, anyone who has

a digital camera who has done a panoramic view knows how hard that can be to get everything just right so it's not easy to do this but there it is. >> incredible. the technology is just amazing. david gallo, thank you so much. for all the bluefin-21 can learn it's only there to take sonar pictures. the next step is when debaris is found to send down other submersibles that can do more. gary tuchman got an up-close look at one vehicle that played a key role in finding pieces of space shuttle "challenger." here's what he saw. >> reporter: at first glance it resembles a spacecraft more than anything else but this is a research sub that has combed the seas doing everything from medical research to ship and aircraft recovery. >> we have an array of light systems on the sub. so you can turn on whichever light you need. >> reporter: jimmy nelson used to spend about 170 days a year on the sub. the johnson sea link submersible as it's known. it's now retired at florida

atlantic's harbor branch oceanographic institution. >> all right. ready to go. >> ready to go. >> reporter: but other manned sea vehicles may be next to line to aid in the malaysia airlines search. if this or another submersible can get where the wreckage is, how effective do you think this could be? >> very effective. >> reporter: this is the view of the submersible in the atlantic ocean. it can go 3,000 feet deep. but like all research sub, it's slow. it only travels just one mile per hour when searching. the sub was called to duty in 1986 after the space shuttle "challenger" exploded. and it recovered some of the wreckage from the ill-fated shuttle. >> we have the capability of lifting around 1,000 pounds of weight to the surface. >> reporter: in the very front of the submersible a tool called a manipulator which does the important work of grabbing, scooping and sucking up samples that are recovered. this sub is about 24 feet long.

it is also about 11 feet tall and it weighs about 28,000 pounds. it has enough oxygen and emergency provisions on board for the people to survive underwater for up to five days. there's also a bat cabin on the submersible called the aft observation chamber. a crew member who keeps an eye on the submersible's vital signs and another scientist share that back area which is only 5 1/2 by 3 feet. so, just to give our viewers an idea how tight it is, this is how you are sitting. this is how i'm sitting and you can be here for hours. but during those hours this is what is taking place. >> so we fire up the sonar system. and it does a sweep and it paints us a picture as it spins 360 degrees. if there are solid targets on the bottom, it will beep and it will kind of paint a small picture of what it looks like and we can motor that way. >> reporter: the use of high-tech underwater manned vehicles is increasing but

jimmy nelson says when looking for wreckage, manned submersibles offer important dimension. sometimes having a human being can spot things an unmanned submersible cannot spot. >> correct. >> reporter: this could be sent in to action underwater in an effort to solve a mystery. gary tuchman, cnn, fort pierce, florida. >> incredible technology. for more on the story and others go to cnn.com. coming up, could a new system for tracking planes with gps and satellites prevent this type of situation from happening again? and the question is, if so, why isn't it being implemented right now? also, life-saving lessons from other deadly crashes over the years. how investigators make sure the saddest moments in aviation history never happen again. and later tonight, breaking news, a cnn exclusive a new al qaeda video is surfacing. a top leader meeting with more than 100 followers. we will tell you why it is so important and who was involved,

and the question is, did the u.s. even know about this meeting? 2 aleve for...h is ...all day relief. hmm. [bell ring] "roll sound!" "action!" ♪ hooking up the country whelping business run ♪ ♪ trains! they haul everything, safely and on time. ♪ tracks! they connect the factories built along the lines. and that means jobs, lots of people, making lots and lots of things. let's get your business rolling now, everybody sing. ♪ norfolk southern what's your function? ♪ ♪ helping this big country move ahead as one ♪ ♪ norfolk southern how's that function? ♪

the crash of flight 370 and the mystery surrounding it understandably scares everybody.

the fact is, though, your drive to the airport is many, many more times dangerous than the actual flight. and there is a reason for that. the business of making planes, carrying passengers and regulating the industry for all the shortcomings we've seen is very much a tight-knit community with a long tradition of learning from past mistakes, or like this anticipating them. it is requiring all aircraft operations in the u.s. be ready for it with the right transmitting equipment by the year 2020, and it's precisely this sort of system that could have made following 370 so much easier and like many innovations it evolved from bitter lessons learned the hard way. randi kaye reports. >> reporter: valujet flight 592 from miami to atlanta, the day before mother's day 1996, the pilots hear a loud boom six minutes into the flight.

>> return to miami. >> what kind of problem are you having? >> smoke in the cabin. smoke in the cabin. >> reporter: the pilots head to the nearest airport. meanwhile, passengers are yelling about a fire. the aircraft rolls on its side and then crashes nose first into the florida everglades killing all 110 people on board. the ntsb determined the fire began in a cargo compartment. >> if we had a fire detection system in this compartment, the crew would have been afforded more time to get the plane on the ground. >> reporter: the faa took those words to heart and as a result revised standards for cargo requiring smoke detectors and automatic fire extinguishers in cargo holds. >> we are on a mayday. we're going down. >> reporter: fire was also a problem in 1983 when air canada flight 797 made an emergency landing at cincinnati's airport on the way from dallas to the toronto airport. it had a fire in the bathroom.

>> we have a fire in the back washroom. we're filling up with smoke right now. >> reporter: incredibly the plane landed safely but half of the passengers and crew died because they couldn't exit the plane fast enough. that gave rise to new fire safety standards, including bathroom smoke detectors and automatic fire extinguishers. today planes are much more fire resistant. carpets and seat cushions are made of a special material that burns slower. passengers can also get out faster thanks to new and improved exit doors and those floor lights that the flight attendants point to every time before takeoff, those were added to save your life, too. smoke in the cockpit was the problem on swissair flight 111 after it took off from new york's jfk airport in 1998. >> we have to land immediate. >> reporter: it crashed

just off the coast of nova scotia killing all 229 people on board. investigators traced the fire back to the plane's entertainment system and flammable mylar insulation. following that crash, the faa ordered all mylar replaced with fire-resistant material. >> we have called for a review of in-flight firefighting standards in the industry. >> reporter: in 1985, we saw a huge improvement in technology to protect us from high winds after delta flight 191 crashed at dallas-ft. worth international airport. it was landing during a thunderstorm. 137 people died. after much research by nasa and the faa, forward-looking radar wind sheer detectors became the standard.aer detectors became te standar standard. the crash of twa flight 800 just after takeoff from jfk airport in 1996 was another hard lesson. >> up in the air and then we saw two fireballs go down to the water.

>> reporter: the ntsb determined an explosion in the fuel tank caused the crash, blaming it on a wire that short-circuited. the faa later mandated changes to reduce sparks from faulty wiring. randi kaye, cnn, new york. joining me once again is safety analyst david souci, author of "why planes crash" and les abend. does it seem like change only occurs in the wake of a tragedy, or is the industry proactive? >> i think dave will agree with me this is what we call tombstone technology unfortunately. >> tombstone technology. >> yeah. when something tragic happens, then these changes occur. it's traditional for the ntsb to kind of and the faa to be at odds. one is a regulatory agency and one finds probable cause and says, "a," we recommend this. dave has probably been at the forefront of this. and it's very difficult. >> you agree with tombstone -- i have never heard that term.

>> it is a term that's been used and that's what the faa has been working away from, a certification process. it was started by nick sabatini as a result of the fact that now it is not just about a singular cause and having it fixed. it is more complicated. as these aircraft get much more complex, you have to look at the relationship between the systems and look for precursors. >> with this gps system that they are going to have in place by 2020 in the united states, would that have made it much easier? i mean, if it was on -- in the area for flight 370 to track it? >> yes, absolutely. the certification process study i just mentioned before, we need to change how we do things, including the air traffic control system which has been in place for years and years and years. the next ge. n came out with this process,

adsb 2 and they would have information constantly about every other aircraft that may even cross their path. >> would it still be possible, les, if a pilot or a co-pilot were able to determine a plane went missing, would it still be possible to do that, to make a plane go missing? >> well, dave and i talked about this new system, the satellite-based system. the airplane regulates the system. t they send it to a satellite system, the ground system sends it to air traffic control. this is what i use in the north atlantic. it is mandated almost totally in the north atlantic at this point and also europe. could it be turned off? you are turning off another system which is basically the flight management computer. dave and i discussed the technology that the transponder doesn't have an effect on it. i have to verify that. but to the best of my knowledge at least on the 77 shg, you have to turn off the flight management computer in order to disable that system.

>> you agree with that? >> yeah, i do, the point of this system is that it can't be turned off. the beauty of it is everybody is interlaced and everybody knows where everybody is. if anyone goes off the system, it is a weak link in the chains and the bells and whistles go off saying there is an aircraft out there. we don't know where it is all the planes, their flight plan is mandated by knowing where everybody else is. >> but this is only going to happen in the year -- >> it is in europe also at this point, mandated in europe but the problem is you have to get the air traffic control people to comply with the system or buy into the system, the next gen system. the malaysian airline, this part of the country -- or that part of the world may not subscribe to that system. >> again, all of this technology is really fascinate, and it's one of the things about what happened to 370 is i think viewers and everybody is learning more about stuff in the aircraft that no one know. david souci, le. s abend, appreciate it. up next, breaking news, a new al qaeda video uncovered by cnn is raising chilling questions. it's showing the largest gathering of the terrorist group and officials believe took place in yemen within the last several weeks.

details on this video ahead. also tonight, our doctor, sanjay gupta on the front lines of a health crisis in africa. the latest on the efforts to contain the deadly ebola outbreak. yea. try alka seltzer fruit chews. they work fast on heart burn and taste awesome. these are good. told ya! i'm feeling better already. alka-seltzer fruit chews. enjoy the relief! i'm mom at the playground the kids get trail mix, and you get a delicious milo's kitchen chicken meatball. i wish you liked my cooking that much. milo's kitchen. made in the usa with chicken or beef as the number one ingredient. the best treats come from the kitchen. i'm bethand i'm michelle. and we own the paper cottage. it's a stationery and gifts store. anything we purchase for the paper cottage goes on our ink card. so you can manage your business expenses and access them online instantly with the game changing app from ink. we didn't get into business to spend time managing receipts, that's why we have ink. we like being in business because we like being creative,

we like interacting with people. so you have time to focus on the things you love. ink from chase. so you can.

more breaking news tonight, as well. a video that could signal a new round of plotting by al qaeda surfaced on jihadist websites and shows a top leader addressing 100 followers in yemen telling him he wants to attack the united states. they are not saying if they were caught off guard and didn't know about the gathering or couldn't get a drone there in time to strike it. barbara starr joins me with the latest. the video is remarkable. the leader of al qaeda in the arabian peninsula and the number two of al qaeda worldwide out in the open talking to about 100 of his followers. >> isn't it extraordinary? this is yemen. this is the area the u.s. considers the most dangerous al qaeda stronghold. they have tried to attack the united states before. they vow to try and attack the united states directly yet again and yet, 100 of them,

including this top leader and other leaders are able to openly gather and have a meeting and talk. it may be propaganda, it may be recruiting, but it is also sending a message to the united states, we feel strong enough. we feel secure enough that we can be out here in the open and we're not afraid that you are going to attack us. so it's a real message. >> there obviously have been a number of drone strikes and some effective in yemen. any idea of when the video was taken? >> the intelligence committee believes it was taken several weeks ago because one thing that is happening in the video is the top leader is greeting several men that al qaeda broke out of a prison this past winter in yemen. and now they are free, and he's trying to recruit them, of course, into his movement even further. they think it was actually in the last several weeks because of that tie to the prison breakout.

>> do we know how many assets or what sort of intelligence we actually have about these groups in yemen? was the u.s. aware of this gathering? >> well this, is the absolute critical question right now. did the u.s. know about it, or is the intelligence about yemen right now so spotty that they did not know? one of the things that concerns the cia, the white house, the pentagon the most is this al qaeda group has gone underground in its communications to a large extent. they are staying off the internet. they are staying off cell phones. they have gone back to using couriers a good deal because they are afraid of u.s. surveillance, of the u.s. intercepting their communications. so this sort of going dark, if you will, is one of the big concerns that the u.s. may not know as much as it wants to about what this group is up to and didn't know that 100 of them were out there meeting in the open. >> fascinating. barbara starr, thank you. >> sure. >> i want to bring in national security analyst peter bergen.

what do you make of the video? do you think the u.s. could have known about this meeting and not taken action? >> i doubt it. i mean, this guy is not only the leader of al qaeda in yemen he's the number two in al qaeda overall, and it doesn't appear from this video there are any civilians in the sequence. they wouldn't take a shot if there were civilians in the area but these all appear to be members of al qaeda. this guy is number two in al qaeda worldwide. to me it doesn't make any sense they wouldn't take the shot if they had it in their sights. >> it's also interesting -- this is a group that's been careful about its communications. given that, why would they have a public gathering like this, make a video and then have it out there? >> i mean that, is very puzzling, anderson, as barbara said. this group is relying on couriers and know from news stories in the past that their electronic communications are intercepted. that's why we have a lot of u.s. embassies closed last year as a result of nsa intercepts. so they're being very careful,

so this sort of flies in the face of being careful because clearly they felt that they could do this with some impunity. >> and clearly felt that it had some sort of propaganda value, some sort of show or display of strength. there's people we don't see in this video who are part of this group, the bombmaker, correct? he's the crown jewel of the group. he's the guy that makes bombs that get on the planes. and he's really gone dark. >> i talked to senior u.s. officials and he's very, very hard to find. at the end of the day this guy is more important than anyone else. he's the guy that can build the bombs that can get on planes that are undetectable and he may have trained other people to do the same thing. you do not see him in this video at all. >> do we know how much power this group has in yemen? i mean a number of people in this video were

broken out of prison in the prison break in yemen. >> i think they control good chunks of yemen in 2011. they have taken a lot of hits. something like 100 drone strikes and cruise missile strikes since president obama assumed office. the yemen army has gone after the group pretty aggressively. so, this videotape actually indicates they feel the pressure is off. that for the past couple of years they've been under a great deal of pressure. >> peter bergen, appreciate your expertise. thanks, peter. just ahead, as ukraine's military begins a crackdown on pro-russia separatists, vladimir putin and is he getting ready to move his troops in? dr. sanjay gupta and the race to contain the deadly ebola outbreak in new guinea getting a firsthand look at the crisis.

marge: you know, there's a more enjoyable way to get your fiber. try phillips fiber good gummies. they're delicious, and an excellent source of fiber to help support regularity. wife: mmmm husband: these are good! marge: the tasty side of fiber. from phillips.

.

new developments tonight in the ebola outbreak in new guinea. dr. sanjay gupta is there reporting on the efforts to contain this mysterious and deadly virus. now, over the last three weeks at least 112 people have died.

14 are health care workers. there's no cure and what makes the outbreak different from others is it reached the capital of guinea, 2 million people not far from an international airport. dr. sanjay gupta reports. >> reporter: you're about to go inside an isolation ward in guin guinea. there's a reason you may not have seen images like this before. these patients are fighting one of the deadliest diseases in the world, ebola. it disarmed their immune system, shut off their body's ability to clot and invaded the organs in their body. up to nine out of ten patients will die. but this horror is isolated. we found traffic to still be busy here. markets are full. children, lots of children, still smiling. you see, as scary as ebola is, it's not particularly contagious. it doesn't disperse easily through the air. it doesn't live long on surfaces either, and people don't typically spread it until they are sick, really sick, and

when that is the case, the patients are not up walking around on the busy streets. they are down in bed. in hospitals or worse. even the dead are highly contagious. >> the story is always the same. >> reporter: dr. pierre rollin from the cdc has helped to trace ebola outbreaks for more than 30 years. >> the risk is not people doing with ebola patient but with regular patient not thinking of ebola. >> reporter: you see, it only takes a small amount of the virus anywhere on your skin to cause an infection. and ace learned, no precaution is too small for the doctors who squa care for these patients. >> nothing gets in or out. >> reporter: tim is one of the doctors without borders. he's from canada. he comes into these settings for weeks at a time. he is not married and he has no children. that would be a job liability, he tells me.

multiple pairs of gloves and masks. the head is completely covered. a multi-layer gown, boots and then an apron. it is positive suffocating in the 100-degree weather. >> these are the final pair of gloves. >> reporter: preparing to treat a patient with ebola is like preparing to land on the moon, but you are their only visitor, the only person helping them survive. they do this so people outside of these wards and the people on the streets will never know what it is like to be inside. sanjay joins us now. the death toll and the number infected. they're stiletto going up but the prime minister says the outbreak is nearly under control. can both be true? >> what happens in these situations, initially because there's some confusion as to whether this is ebola or not, you suddenly get a lot of cases as people realize, previously sick people had ebola. so the numbers are still going up. the rate at which they are going

up has slowed down a little bit. but it is important to point out that it will be some time from now, about a month and a half before you can even say the outbreak is over because of the incubation period. >> it is incredible to see the video you and the cameraman neil shot. to see inside, i feel for the patients there. it must be so terrifying. "a," to know the mortality rate of this, to have the doctors and nurses to be completely clothed in protective gear, which, of course, they have to be. it has to be so terrifying or isolating. when will they know or how will they know when the outbreak is over? >> yeah, it is amazing, imagine that somebody has a headache, has fever, has joint pain and they end up getting tested for ebola. and the next thing they know, they're in this isolation ward. the only people they're seeing are dressed just the way you saw. that's their reality. they're already very sick and

you can imagine how scared they are, as well. the way they figure out when the outbreak is over, because the virus can incubate for a period of time, up to 21 days they say, before someone might show symptoms. the general rule of thumb is they wait two incubation periods for 42 days. if there are no new cases, they say the outbreak is over. that is typically how they measure the outbreaks. >> and you and i were in cameroon doing a report on the virus, and there is still so much we don't know about this. i mean, we don't to where the reservoir for this is, where exactly it comes from. >> reporter: it is so fascinating. it's such a medical mystery. they don't know. and just to give you a little bit of an idea of the process where the outbreak occurs, the epidemiologists, these virus hunters will go in here

and capture hundreds if not thousands of animals, trying to find the ebola virus, what are known as antibodies, the response to the ebola virus, anything, any kind of clue. they sort of think that fruit bats may be the reservoir, but after nearly 40 years, anderson, they still cannot confirm that. they have not proven that. >> wow, sanjay, we careful. we appreciate you being there. and for more information on the doctors and how you can help to fight the virus, go to cnn.com/impact. vladimir putin and the ukraine. and oscar pistorius reading a valentine's day card written by his girlfriend, one she never gave to him because he killed her when we return. to be this awesome. and you...rent from national. because only national lets you choose any car in the aisle... and go. and only national is ranked highest in car rental

customer satisfaction by j.d. power. (aaron) purrrfect. (vo) meee-ow, business pro. meee-ow. go national. go like a pro. became big business overnight? ♪ like, really big... then expanded? ♪ or their new product tanked? ♪ or not? what if they embrace new technology instead? ♪ imagine a company's future with the future of trading. company profile. a research tool on thinkorswim. from td ameritrade.

a research tool on thinkorswim. [ female announcer ] some people like to pretend a flood could never happen to them. and that their homeowners insurance protects them. [ thunder crashes ] it doesn't. stop pretending. only flood insurance covers floods. ♪ visit floodsmart.gov/pretend to learn your risk.

let's get caught up on some other stories we're following. susan? >> ukraine launched its first military action against

separatists in its eastern region a day after they ignored a deadline to lay down arms and meanwhile, vladimir putin weighed in telling germany's chancellor angela merkel ukraine is on the brink of civil war. oscar pistorius facing a fifth and final day of cross-examination at his murder trial. the disabled athlete testified he didn't consciously pull the trigger. the night he shot and killed his girlfriend, reeva steencamp. afterwards, the defense had him read a valentine's day card that reeva intended to give him the day she died. >> the trial will wrap up in may. also today, charges filed against the suspect in the killings of three people near kansas city, he could face the death penalty under one of the murder charges. police say they have determined the shootings were a hate crime. federal prosecutors are still investigating. and the white house says it will award the medal of honor to

former sergeant kyle white, the army veteran tried to save fellow soldiers during a firefight in afghanistan in 2007. his only cover from enemy fire was a single tree on a mountain cliff. anderson? an incredible hero. as you saw, the day ends in boston with a chilling reminder of what happened a year ago, the suspicious packages that were detonated. and in the year since three people lost their lives, boston strong became the rallying cry at the white house today the president obama observed a moment of silence for those who died. in a statement, the president thanked the first responders and those who showed the spirit that city was built on, perseverance, freedom and love. here's some sights and sounds from boston today. ♪ up over the clouds we long to be anywhere but here in this moment, 365 days an hour after hate and violence disrupted a beautiful april day.

♪ to see all around >> it's an honor to be able to thank and embrace the first responders who carried some of you to safety. >> the biggest lesson of all the lessons i have learned over the past year is that something in your life, in anyone's life can go horrifically, terribly wrong in a matter of seconds. yet it is up to us to make every single second count after because, believe me, they do. >> i'm glad to join in the remembrance of crystal and martin and sean. i'm glad to share in acknowledging and supporting the families who survived then and the other survivors, many here, and some not yet ready to be here who still hurt from this tragedy and yet inspire us with their determination. >> we are boston. we are america. we respond. we endure.

we overcome, and we own the finish line. ♪ >> boston strong. that does it for us. thanks for watching. our coverage continues now with "cnn international." plucked from a sinking ship off the coast in south korea. and we will have the latest on the oscar pistorius murder trial. and one year later, boston determined to persevere. >> it's about dancing again after losing a leg, starting a marriage forged in tragedy,