Epidemiologist Chikwe Ihekweazu drove through the empty streets of Wuhan in February, observing the Chinese city at war with the novel coronavirus. “It was incredible,” recalls the director-general of the Nigeria Centre for Disease Control (NCDC) in Abuja. “This huge city looked empty, but behind every window were families supplied with food, medicine, everything they need to survive,” he says.

Ihekweazu’s thoughts drifted to Lagos, a chaotic Nigerian city where roughly two-thirds of its 21 million people live in informal shelters without electricity or running water. “The challenge to switching off society would be exponentially more than in China, Europe or the US,” he says. But authorities are now trying. On 30 March, they banned domestic travel in or out of some states, by air or road, and closed businesses.

Like many low- and middle-income countries that are now seeing the arrival of the pandemic, Nigeria is facing grim decisions. Its health systems are much too weak to handle an explosion of COVID-19, the disease caused by the new coronavirus, named SARS-CoV-2. One analysis found that at the peak of its epidemic, Wuhan, China, required 2.6 beds in an intensive care unit (ICU) for every 10,000 adults ¹ . Italy has less than half that capacity ² , and is overwhelmed. But some low-income countries have just one-hundredth of Italy’s — one ICU bed per million people — according to a 2015 study ³ . Without intensive care, many more people may die than in the countries hit hardest so far.

Without the luxury of well-funded hospital systems, Nigeria and other low- and middle-income countries began ramping up measures to keep COVID-19 from spreading as soon as they confirmed their first cases of the disease — in some cases, even before. That includes shutting down most activities with the threat of arrest, quickly rolling out tests to detect genetic sequences from the virus and a willingness to deploy rapid, easy-to-use tests — even if they are not as accurate as the conventional variety, which requires more laboratory capacity.

However, these countries face exponentially more constraints in funding, capacity and infrastructure than wealthier nations. They cannot simply follow the playbook of exemplary countries, such as South Korea and Singapore, which curtailed their outbreaks rapidly.

But with Wuhan, Italy and New York City showing them how tragic the pandemic can be, these nations are scrambling to prevent total disaster. Ebola outbreaks in Africa have shown, for example, that when hospitals are overwhelmed by one infectious disease, swathes of people die from a lack of care for malaria, pneumonia and other curable diseases, as well as care during pregnancy and childbirth. Snapshots of four countries — Nigeria, Peru, El Salvador and Kenya — provide a look at the next phase in the pandemic, as the battle moves to low- and middle-income nations that are struggling to contain the coronavirus before it gets out of hand there. “We need to push,” Ihekweazu says. “I’m exhausted like never before.”

Nigeria (139 cases, 2 deaths)

Ihekweazu’s team was battling an outbreak of the deadly disease, Lassa fever, when COVID-19 exploded in China. Seeing the potential for the coronavirus infections to spread, he asked his team to obtain diagnostic tests. On 3 February, his laboratory received supplies for tests that detected genetic sequences from the new coronavirus, using a technique known as PCR; these were developed by researchers in Germany and distributed by the World Health Organization (WHO).

Soon after, Ihekweazu travelled with an international delegation of infectious-disease researchers on a WHO mission to Wuhan and other cities in China. Their goal was to learn about China’s COVID-19 response strategies and gather information about the disease’s severity and transmission. Ihekweazu was still in quarantine in Abuja after his return when Nigeria confirmed its first case, on 27 February. The infected person had recently returned to Lagos from Milan, Italy. One of the NCDC’s collaborating labs in Lagos sent some of the sample halfway across the country to Christian Happi, a microbiologist at Redeemer’s University in Ede. His team sequenced the genome of the coronavirus within three days, then made it available online. It was the first SARS-Cov-2 genome sequenced on the African continent.

When the number of cases in Nigeria rose to eight on 18 March, authorities banned people arriving from countries with more than 1,000 cases, including China, Italy and the United States. Three days later, they banned gatherings of more than 20 people in Lagos and Abuja, and asked non-essential businesses to close. Lagos’ notoriously heavy traffic dissipated, but people were still walking about. On 29 March, as cases approached 100, President Muhammadu Buhari announced that domestic flights were suspended, and checkpoints would block roads to prevent non-essential travel between states. "This is a matter of life and death," he wrote on Twitter. "Look at the dreadful daily toll of deaths in Italy, France and Spain."

Policies barring domestic travel have occurred more swiftly there than in many other countries. For example, on 28 March, the US Centres for Disease Control and Prevention asked residents of New York, New Jersey and Connecticut to not travel. At that point, the three states had confirmed more than 65,000 cases.

Yet despite the head start on social distancing and testing, the NCDC is now backed up because the six labs in its network, including Happi’s, don’t have enough capacity. Ihekweazu asked Happi to hold off on sequencing full genomes because testing has become the number one priority — and Happi’s lab has the equipment and expertise to help. “We are working in shifts, 24/7 now,” Happi says. His genomics centre has 16 people running PCR-based tests, but he’s looking for volunteers to join the team. He's also seeking protective gear to ensure the team won’t be infected, but stocks of face masks and laboratory aprons are running low.

And at a national lab in Lagos, WHO technical officer Dhamari Naidoo is trying to obtain more tests for Nigeria, so that officials there can isolate people with COVID-19 before they spread the disease further.

“For a country the size of Nigeria, we should be getting to the stage of 5,000 to 10,000 tests per day,” Naidoo says. But travel bans across Africa have made flights scarce, slowing deliveries of laboratory and medical cargo. Naidoo has been told that equipment for running more tests simultaneously won’t be available until late April. And some components of the PCR tests currently in use have become scarce. “Everything is being diverted to Asia, Europe and the US, to help those countries respond to their own outbreaks,” she says. “No matter how well we planned — we cannot plan for this.”

Peru (1,065 cases, 30 deaths)

Peru announced strict social-distancing measures soon after they confirmed their first case of local transmission. On 15 March, at around 70 cases, the country closed its borders and schools, told residents to stay indoors except for essential errands during the day and announced a country-wide curfew of 8 p.m.— which has since been brought forward to 4 p.m. in some places. “These measures are important, because Peru is a country with 32 million inhabitants with a poor health system,” says Alejandro Llanos-Cuentas, an infectious-disease scientist at Cayetano Heredia University in Lima.

What’s more, Peruvian authorities are enforcing those rules. At a press briefing, President Martín Vizcarra told reporters that police have already arrested 21,000 citizens for violating the laws. Police register the offenders in a database and send violators home. "We are taking drastic but necessary decisions to get out of this situation together," he said.

“They will have a police record, and they will lose time and money with justice trials,” says Llanos-Cuentas. Authorities are publicizing the daily number of arrests in an attempt to warn others against violating the lockdown rules. The government is also adopting measures to support people who have lost their income owing to the restrictions, such as cash payments and food distributions, Llanos-Cuentas says.

Yet as cases climb, the need to test people grows ever more urgent. Only two labs in Peru — both in Lima — are able to conduct the PCR tests, which require relatively expensive laboratory equipment and supplies. To expand testing outside the capital, the government has asked for a million rapid-diagnostic tests produced by China and South Korea, says Leonid Lecca, director of the Peru branch of an international, health-care organization Partners in Health. These tests detect either proteins on the coronavirus that trigger an immune response, or antibodies that people have produced in response to an infection. But the rapid tests that are currently available aren’t as accurate as the PCR tests. And those that identify antibodies are unlikely to work until a person is several days into an infection. But the tests provide results in as little as ten minutes, and require less-sophisticated equipment. Last weekend, Lecca says that more than 130,000 rapid-diagnostic tests arrived in Peru.

K. J. Seung, a Boston-based doctor with Partners in Health, says the tests might help hospitals to gauge how many health workers have been infected — and whether they are now immune to the virus. The tests could also be useful for people who have had symptoms for several days, but remain at home. When people test positive, Seung says, medical teams can then attempt to locate their close contacts. Meanwhile, the infected individual can take extra measures to isolate themselves, or head to isolation centres that the Peruvian government is building. In addition to constructing dedicated sections in hospitals, it has converted apartments originally built to house athletes for the 2019 Pan American Games into isolation units. There are around 3,000 rooms in total, intended for people who test positive but don’t require intensive medical care.

Seung says that tests that don’t require advanced facilities can also help researchers to learn how COVID-19 is spreading in different places. Like researchers in Nigeria, Seung is anxiously awaiting easier-to-use tools for PCR-based diagnostic tests. By May, he expects Cepheid, a biotechnology company in Sunnyvale, California, will have scaled up production of COVID-19 detecting cartridges that plug into its GeneXpert PCR machines. These machines already exist throughout Peru because they’re typically used to diagnose tuberculosis. But because the supply chain for existing diagnostic tests is already strained from demands in the global north, Seung is concerned about access to new technologies that come on board. “I worry that Americans will suck up all the cartridges” for the GeneXpert machines, he says.

Kenya (59 cases, 1 death)

Abigail Arunga, a journalist in Nairobi has been hearing police helicopters flying overhead. On 25 March — with 25 confirmed cases — Kenya imposed a curfew of 7 p.m., and announced that people should leave home only for essential duties. “They’ve been enforcing it very violently,” she says. Kenyan police have beaten and tear-gassed people even before the curfew starts, drawing condemnation from Human Rights Watch, a non-profit organization in New York City. On 31 March, a teenager standing on his balcony was shot, by police enforcing the curfew in the street, according to media reports.

Police abuse is not new in Kenya, says Arunga. But their tactics could backfire if communities protest, especially if people can’t get access to necessities. “If the government doesn’t have a database for how to administer food, people can’t eat, and that’s a recipe for a riot,” says Arunga. She adds that many people in Nairobi question the gravity of the disease, saying that it’s a problem that affects only upper and middle-class people coming to Kenya from the United States and Europe.

Evans Amukoye, a paediatric pulmonary researcher at the Kenya Medical Research Institute in Nairobi, says that convincing the public to take COVID-19 seriously is difficult, because relatively few cases have been confirmed, so far. Authorities decided to impose social-distancing restrictions preemptively, he says, because Kenyan researchers felt that places that took such measures early in their outbreaks, such as in Beijing, fared better. “If it explodes, it will be bad,” he says.

But like Nigeria and Peru, Kenya is struggling to ramp up tests, facing shipment delays and expecting that the equipment and reagents they need may be absorbed by the United States — which now has an outbreak twice the size of China’s. Amukoye says a key priority is to study how the coronavirus affects Kenya’s population which, like many countries in Africa, skews young. But Amukoye and his colleagues don’t know whether these demographic factors will help, even though COVID-19 is more deadly in older people. “We need to learn how it behaves in poor people, malnourished people, people with HIV who are immunosuppressed, or who have non-communicable diseases that are not diagnosed, or not well controlled,” he says. Kenyan scientists have joined a consortium of researchers from other low-income countries seeking to address these urgent questions, and roll out clinical trials catered for low-resource settings.

El Salvador (32 cases, 1 death)

El Salvador was among the fastest in the world to implement COVID-19 responses, says Luis Romero Pineda, deputy project coordinator at Médicines sans Frontières (MSF, also known as Doctors without Borders) in San Salvador. With only around 100 ICU beds in the entire country, El Salvador faces a potential disaster if COVID-19 numbers surge.

Even before any cases appeared, on 13 March, officials suspended classes, sports events and gatherings of more than 20 people. Four days later, they banned travel from several countries with outbreaks. The following day, the government confirmed the first case in a person who had returned from Italy. A few days later, authorities declared that everyone must stay inside, except for essential duties. To compensate, the government said it would provide households below a poverty line with $300 per month to purchase food and supplies. They also imposed a curfew that has been strictly enforced. So far, the government reports more than 4,000 arrests. At first, people were detained together in large tents. But that policy is in flux, with the recognition that the coronavirus spreads rapidly in dense settings. In areas of El Salvador controlled by gangs instead of the government, some of the largest gangs are threatening to fine or beat people in their territories who break curfew, reports the Salvadorian newspaper El Faro .

As the number of cases slowly rises in El Salvador and other low- and middle-income countries, cracks are beginning to show. “This may be a lose–lose situation,” says Kalipso Chalkidou, a health-policy analyst at the Center for Global Development in London. Although some nations have acted quickly by imposing restrictions, they are hampered by economic, social and political factors that could weaken their defences. And those actions could have dire repercussions, such as driving up non-coronavirus deaths or triggering violence in populations that lack food, says Chalkidou. “We need to think about what we can do realistically, and try to preempt the grave consequences of measures,” she says. For example, she adds, the World Bank and the International Monetary Fund must try to find economic solutions, such as through loans or by forgiving debt.

In Nigeria, Ihekweazu is trying to maintain hope. “We are resilient,” he says. “We will find a way to survive”.