host: welcome to "global 3000." cyclone idai brought devastation to zimbabwe last year. how is the reconstruction coming along? fake news s and hatepepeech -- that's also a feature of social media. does this pose a danger to democracy? but first wewe go to the k kia district of nairobi, where the coronavirus crisis is causing many to go hungry.

malaria, tuberculosis, hiv. these often fatal diseases are still widespread in africa. and now they've been joined by covid-19. the worst is yet to come on the continent thatat is home to o3 billllion people, , warns the d health organization. africa has t worst h hlthcare in the world, with one doctor for 3300 people on average. by comparison, oecd d countris have one d doctor per 300 peop. the coronanavirus is exaxacerbg poverty anand hunger, eveven in countries like kenenya, long considered east africa's ececonomic powerhouse. more than two thirds of kekenys work in the informal sector as artisans, veors, cleleers. most of these jobs have been wiped out by the p pandemic. now, many ople canan only afafford one meaeal a day. and residents of nairobi's biggest slum are desperately worried about their livelihoods and their children's future.

reporter: it's a tense evening in nairobi's kibera district. an ambulance has brought a weak, elderly man back to the village, who has supposedly tested negative for the coronavirus. but many here suspect that he's still sick. it's not entirely clear whatat his status is, but people are worried enough to force the ambulance to take him back to hospital. "do you think this is a coronavirus dumping ground" shouts someone in the crowd. the next day, two bystanders tell us it nearly erupted into violence. evelyne: the problem with the crowd was, how can they bring a covid patient here with no proper handling, because he was a covid case. because that is a way of transmitting covid to other people. oloo: the driver and the police agreed with us that they'd take him back to hospital. because the crowd was shouting,

"burn the ambulance, set it on fire." reporter: officially, there have been around 11,000 cases in kenya so far, which is relatively low, but there is widespread fear of a major outbreak. the country responded quickly, with lockdowns and compulsory masks. but the economy is suffering greatly. and the number of infections y has been climbing faster recently, in poorer quarters like kibera as well. this district of kenya's capital nairobi is suffering especially badly. many here now depend on food donations. one woman is close to tears. she doesn't have a mask with her. the volunteers simply give her a warning as they hand her the food parcels. these are typical scenes, and in amongst it all, the children. schools have been closed

because of the coronavirus, a potentially devastating blow to the future of the younger generation here. mothers like sophia ashihundu can't home school their children. the family has no laptop, tablet, or computer, and the power is often out anyway. sophia: i can't check their answers. i didn't go to school. so instead they go to the neighbors who do that for me. reporter: sophia's 14 year old daughter sheila gets up at 6:00 in the morning to do o her homework. she waits eagerly for school lessons to begin on the screen at her neighbor's house. sheila: sometimes i just lose hope because we don't have anything. we don't have a father.

my mother is struggling for us. i need to learn for her so that i can help her. in the next life, i don't want to suffer likeke this. when i grorow up, i want to be the best surgeon so that i can help my mother. reporter: sheila's frightened of missing too many lessons. so she goes round to study at her neighbor's whenever they're at home. since the beginning of the crisis, the government has been working with the united nations children's fund unicef to expand remote learning school programs. it's an attempt to avert the worst, says unicef's janeanne kiviu. janeanne: even b before covid, the learng crisis was very high in educatioion where chilildren e not able to achieve the learning outcomes that they need to achieve at a particular age. and you can imagine, plus the

covid, then these learning outcomes, the achievement of this becomes a problem. reporter: if the power fails and the signal cuts out, then sheila simply has to miss out on the class, which is frustrating. but remote schooling at least offers some sense of stability during the crisis. this is also the reason why sophia hassan invites round as many as 10 kids a day to use her tv in the kibera district. she wants to protect them from another kind of threat during the crisis. sophia hassan: it is important in that, here in kibera, there are so many cases of violence, domestic violence, rape. so i'm trying my best to put them together so that they don't go and involve themselves there. reporter: there are many like sophia hassan, trying to help others.

they're the backbone of the nairobi's kibera quarter. people who won't give up, no matter how long the crisis lasts. host: in brazil, the coronavirus has been downplayed by the country's president jair bolsonaro. despite testing positive, he has pressed local governments to end lockdown measures and social distancing. the outbreak in brazil has claimed the second-highest number of deaths after the u.s. yet many brazilians are retunecessity. repeporter:avis it's a tough job wororking asa snack vendor on copacabana beach. laelson de oliveira wanders up and down in the sweltering heat for hours. he has no other choice. laelson: selling on the beach is still banned, but i just had to work again, because the government

doesn't provide enough support. reporter: copacabana beach is of course an icon of rio de janeiro. it's alslso a placwherere rich meets poor. laelson travels for four hours every day just to work here. if things go well, he barely takes 100 euros home with him. laelson: i know this disease is killing a lot of people. but if we all stay at home, we'll die anyway, only without work and food. reporter: strict sociaial distancing measures are t theoretically n place, but the police have long given up trying to enforce them. almost no one here follows the rules. it's an open goal for the virus as more and more people take ill and die. and while the state is failing to control the situation, pressure mounts to open back up as if everything's returned to normal. that's plain to see as we leave the beach. the usual hustle and bustle has returned to the alleyways of

the old city. almost half of brazilians work in the informal sector, and live day to day, so they have no choice but to be out. only a few shops were supposed to open after quarantine, but hardly anyone stuck to that. vinicius: we're brazilians, we don't give up. we battle and we muddle through. city security came round a couple of times and tried to stop us working again. i just quickly tidied everything inside and leftft te door half open. reporter: carol and her family are also back in business selling food from the trunk of their car. the lockdown took a big financial toll on them. carol: we're taking the risk because we have to work. if we could stay at home, we would. but we couldn't afford to any more. reporter:

after eating into their own stocks for a while, carol's mother h has gone back to cookg for other r people. every night, into the morning. on the menenu today is beef wih rice and beans. one portion costs a a little or two euros. they used to sell 100 meals a day. now it's about 30. carol had high hopes of president jair bolsonaro, and his promised economic boom. but those hopes have been dashed by his handling of the pandemic. carol: he rununs around without a mas, he's careless. he shakes people's hands. he's no role model. but a lot of people follow his example. they don't stick to the rules either, because he's not a good rolrise unabated.orter: tsome regions have had to buildd mass graves. brazil is in strong contention withth the u.s. to become the world's worstt

affected country. the poorest are getting the worst of it. we travel to the favela maré, one of the biggest in rio. people here seem to feel abandoned. a truck has just arrived with donations. today, it's soap and disinfectant. volunteers from a citizen's initiative help unload the truck. ana: we have to fend for ourselves. that's the way it is in the favela. reporter: the younger ones are doing most of the heavy lifting. it's hoped they have a better chance of surviving a covid-19 infection. 20-year-old student nandyalla is one of the organizers. nandyalla: there are so many dead and so much sadness among family and friends. that's what motivates us. we've already lost a member of the team to the coronavirus, and my friend who's just been

helping out is infected right now. reporter: it's especially dangerous to distribute goods in the back alleys of maré, where armed gangs rule the streets. the volunteers took this footage for us. outsiders are not welcome at the moment. the virus is spreading, and the inhabitants have no real means of protection. it's not clear how many people in brazil's poorer quarters are falling victim to the virus, because people who don't get tested don't turn up in the statistics. what is certain is that the number of deaths has multiplied dramatically. nandyalla feels betrayed by her own government. nandyalla: the government doesn't care about the favela. we're really angry with the state. because it doesn't just neglect us, it's also racist. we suffer at the hands of the police here in the favela. most of the young black people who are killed come from the favela. most of the black people who die of covid-19 come from the favela.

right now, we're at the epicenter of the coronavirus. reporter: and they're the very people who are now packed onto buses and trains again. to go back to their jobs, doing things like cleaning high end shopping malls, so that those who o can afford i it can safy consume. the favelas are the city's engine room. cleaners, laborers, street sellers, but also teachers, nurses, and bus drivers live here in these crowded settlements. collectively indispensable, but easily replaceable as individuals. for decades, this is the cynical eqequation that's kept brazil running while keeping rich and poor worlds apapart. host: fake news and conspiracy theories, like the nion thatat, have floururished on s social ma during theandemimic. much disinformatation has spred on facebook,k, reminding mananf the platform's role in the 2016 u.s. election campaign.

ck then, with the help of tata analys fifirm cbridgege analalytica, wealtlthy right-wiwingers and rurussin operativives targeted d votern facebook, , possibly influeneng thoutcome the electio critics social media saits potential l for manipulation undermines democracy. reporter:: the internet, a seiningly ininvisible and d intangible p. but there are also invisible dangers lurking re beneath the surface. christophpher: to me,e, it feels like blilinga frogog. u know, very slow incrcremental chchanges, and w we end up ase boileded frog. repororter: britain's brexit andhehe u.s. uelection of donald trump weeal chamonthe e fit politicalp ase campmpgns to use algorithms to target and manipululate users. peter: s so, it's a nenew forf censorshship, a veryvevery rarange on repeporte

democracy is v vulnerable now, because e we are. vulnerable to manipulation that we don't even notice. we meet someone in london who's playeded a part in that mamanipulation. christopopher wylie workrked f cambridge analytica, the company behind the worst case ofofata abuse e in facebook's history. it was co-foundeded by formemer white house chief strategist steve bannon, and ended up serving as a propaganda machine. it was co-christopher: formemer what cambrge analytica s showed is h how easy it i is to infile amererican politicical discoue and mapulate it. the harms that he e come from that, to me,e, is akin to, you six years ago, wylie left . ststructio repeporr: he b became a whisistle blowerd testified before the u.s. senate. now he's writt a a new bk, a a peek inside the engigine room f mental mananipulation.

christopher: thehe purpose of e algorithms that cacambridge analytica created were to identify people who o were moe prone to neurotic traits, or conspiratorial ideation. repoerer: eof facebook users, to identitiy alatheir inindividual feaears. totother with psychologists, cariridge anyticica wathen abable to develop p targeted popolitical propopaganda for different types of people. it had the power to skew someone's viewpoint, e even ify stst a f degrere. christstopher: raraer than talk in public, i n n whispeintoto each and evevr single person's ear. i remember wchching a cuss grgroup where african amererin women n would talk abobout how

vulnererable they would feel gogoing to theheir second orord job at night, walking alone the middle o of the cityty, and ththat, you know, they neededa gun to protect themselves. if you're a a right-wing campaignerer, you go, "o"okayo let's igignore all thehe rae jujustice stuff,f, let's ignoroe equality. let's focus onhe f feeng of being a vulnerabable black womn in thehe middle of t the nigh" rereporter: cambridge ananalytica no l lor exists, but the tools ththey developed still do. journalist peter pomerantsev researches propapaganda at the london s sool of economics. peter: in thehe west, we did d have a sosocial contracact for 60 yes arounderertainypes o of diouourse th we'e'd arnt from totatalitarian regegimes thate don't ususe. and suddenly, althisis stuffothe to d differe plalace. do notot do, demeanining the or in politite discourse.e. yoyoknow, we could hint at it, e e tabloi plalayewith thahat,

you know, ththey kind of w wern ececho of nazi o or soviet prpraganda. but to just t see nazindnd soviet-style progandnda all the time on the e internet evevery? at's pretty bloody shocking. reporter: one tact used to destabilize democracies is to flood the internet with contradictory narratives. this is frfreedom of speech, bt used in a way to camouflage the trututh. peter: what they y do is something g t some people call censorship through noise. they f flood the infnformation space with s so much disinformation, inrmation, chaos, andhat steve nnon calls "flood the zone with bull--," that people can't tell what's true or falslse anymore. so, this i is censshipip not through constricting, but throh h opening g up the gatesf informatioion. reporter: it's like a place has been created, where freedom of speech statarts to attack itse. it's's easy to believeve tht politics will never catch up with the digital wororld. but that may note e the case..

christopher:r: imagine e entering intnto a building that was built by an architect that didn't have to follow anyny safety stanandards becacause he puts terms and conditions at ththe front of te door.. and what we have in software enengineering and data architectuture is no ruleses. weeeeed to he a legislivee framework k for digitall tenolology that rerecognizes tt it is a prproduct of engineerig theye nonot seices. . rerter: the books by wylie and pomerantsev servrve as a warni. none from cambmbridge analytyta suffereded any conseququencesr their actions. there arcacalls foa regugulatory body y to approve algorithmsms. "move fastst and breaeak things" was once a facebook motto. it's obviouslyly worked. hoso: in o our global ideas series, e focus on climate change projects that inspire and offer solutions. this week we go to zimbabwe, where a devastatating cyclone struck in 2019.

we meet people in the region around chimanimani national park who a are involved d in rebuililding and envnvironmenl protection in the wake of the storm. reporter: 18-year-old takudzwa tavatya's home village ngangu remains devastated. she was here when cyclone idai tore through it in march, 2019. several of her friends were killed in the disasaster. over 200 hououses were destroy. even now, takudzwa can barely come to terms with the power of the storm. takudzwa: this place you are seeing, it was quite a wonderful place. there were lots of things. but in a little moment, everything was ruined. reporter: idai also caused a series of landslides in the nearby chimanimani national park. chimanimani is home to 200 different species of bird.

togarasei fakarayi has been working for nature conservation organization birirdlife zimbabe here since 2013. now, reconstruction is also on his list of tasks. togarasei: environmental restoration is something key. now we have seenen what has happened within the urban set-up of chimanimani, which is this is a high density area and it's an area that also needs restoration as well so that the environment will not continue being degraded. reporter: the environmentalist and his organization are active in six villages. in one of the tree nurseries, villagers like john njanji have joined together with others to grow new trees. john: we sit down as a community to rehabilitate our area by

planting trees from different species, so we started by choosing some locally available trees so that we nurse them into our nursery. reporter: fakarayi is worried that invasive plant species might take root and spreadad in the areas destroyed by idai. native plants would be of much more use to the environment and the people here. togarasei: they can grow in a changing climate, they are more resilient than a new s speciesf trees, b because they y are uso already the local conditions, the soil type, and also the rainfall that they used to receive here. these trees have to be replanted to increase the windbreaks. reporter: twice a month, fakarayi gets togethther with represesentats of t the surrounding villages. the environmental scientist gives advicece on how to use te

natural resources. and he tries to instill an awareness of nature, the animals, and especially the birds in the area. togarasei: as they come from the different villages, the knowledge that we input into this group of people, we are assured that it will also spread to the other six villages in chikukwa community. reporter: john njanji has put birdlife's advice into practice in his own garden. alongside his millet and maize crops, he e now also keeps a fruit orchard. john: i realized that an orchard is one of the many sources of income generation for me. long before i started this, i used to only grow maize and vegetables. i later grew to appreciate the orchard.

the different trees nourish the soil and i am spoilt for choice, because as some fruit trees are growing, others are already bearing fruit. reporter: njanji sells his fruit in neighboring villages, and that ensures him an income even during the coronavirus crisis. togarasei fakarayi is happy with the orchard's abundance, because it's also important for the whole area. togarasei: there is a diversity of birds in the c chimanimani mountain, and these ones, they share the border with the national park. so there are a lot of birds that also visit, that are living within these commununities, in the forests, and also they come into orchards where they can actually get some fruits, and soso feed on fruits. so b by having different orchards, they also supply fooo to many y organismsms such s

birds, other insects. reporter: insect p populations were also ravaged by cyclone idai. most of the 50 beehives here were destroyed. traditionally, farmers here hollow out tree trunks to serve as hives. now, birdlife zimbabwe is helping them to make beehives out of timberwood as a aay of protecting the remaining trere stocks. harry: we have e fruit trees s in the village,e, bees go in and spred the pollen, , and this is good for our harvrvests because evenentually we will have more fruit. and when people rereize that there are beeses in isis area, they won't chop the trees down because they are fritenened of them, so the bees also provide some form of security. reportrter: 600 hives s are pla. ththe environmentalists s bele that if people have a sufficie s source of incncome, ththey will be m more likely t o protect the environment. host: that's all from "global 3000"

this time. do write in and tell us what you thought of the show. and look us up on facebook, dw women. see you soon. ♪ [captioning performed by the national captioning institute, which is responsible for its caption content and accuracy. visit ncicap.org]

narrrator: to o keep big cities afloat, great wawater demandnds require g greater watater solut. water protectors combat climate change and the illegal wetland development floodiding towns in argentina. in n mexico c city, citizens use innovative education models and techchnologies to address the city's water issues.