Over the past year, health crises have sparked fears and dominated headlines across the globe.

In Congo, an Ebola crisis that erupted the year before continued to grow, and violence against health workers hindered efforts to control it. In Samoa, a deadly measles outbreak spread so rapidly that unvaccinated families were asked to hang red flags outside their doors to help vaccinators find them more quickly. In Pakistan, hundreds of children born to HIV-negative parents suddenly tested positive for the virus, which can cause AIDS. In the United States, mysterious vaping-related illnesses killed several young people and sent many others to the hospital.

Here are the stories behind some of the most frightening global health crises in the past year.

Ebola

When Ebola struck West Africa in 2014, it spread like wildfire. By the time it was finally controlled, more than 11,300 people had died. Lack of infrastructure, distrust in health workers and a slow recovery from long civil wars in two of the affected countries complicated efforts to arrest the spread of the virus.

When the virus hit Congo in 2018, it was not the first time that the country had to handle an outbreak of the hemorrhagic fever, but experts worried that the situation was ripe for a disaster. Conflict has plagued parts of Congo for decades, slowing development in the country’s east, where the latest outbreak took root. Among civilians, there is widespread distrust toward outsiders, particularly MONUSCO, the massive U.N. peacekeeping mission that has faced a barrage of criticism over alleged inaction in the face of various crises. The east, far from the capital, Kinshasa, lacks government oversight, and small militias and other armed groups continue to operate throughout the region, further complicating the response to such an outbreak.

In the past 16 months, at least 2,200 people have died from the disease in Congo, and health workers have been attacked trying to treat them. The violence has forced some organizations to shutter crucial clinics, and at least 500 health workers have been relocated.

After a brutal attack on a clinic last year wounded a number of front-line responders and killed a logistician helping with treatment efforts, a young woman who witnessed the attack told The Washington Post’s Max Bearak that she and her colleagues “all got into the same room and hid under the beds so at least we would die together.”

She said they listened to a colleague scream as the armed men “chopped her with the machete outside the room. The attackers did whatever they wanted for hours, as if they knew no one would stop them."

Measles

The United States declared measles eliminated in the country nearly two decades ago. But as misinformation about a measles vaccine spread, more and more cases began to pop back up in the past year.

Hundreds of people came down with the disease in New York, forcing the city to declare a state of emergency. By the time it was finally declared over, 654 people had been diagnosed with measles, and the city had spent $6 million trying to stem it.

Elsewhere in the world, efforts to control measles may have been even more complicated.

In October, Samoa declared a measles outbreak. It spread quickly across the Pacific island nation, killing dozens and sickening thousands. Many of the dead were children, leading the government to implement drastic measures to try to slow it down. It shut schools across the country, banned children younger than 17 from public gatherings and asked families that had not yet been vaccinated to hang red flags outside their doors to alert health workers going house to house to vaccinate people.

Measles is dangerous not just because of its immediate threat of illness. As The Post’s Lena Sun reported last year, new studies show that measles can also make your body forget how to fight other dangerous diseases.

HIV

When hundreds of children in Pakistan’s southern Sindh province began manifesting HIV symptoms last year, doctors were confused. Babies typically contract the virus from infected parents during breast-feeding, pregnancy or birth. But these children’s parents were HIV-free.

Officials then traced a number of the children back to a single doctor in the area, and they began investigating whether he had used unsafe syringes, infecting children instead of protecting them. The outbreak stoked fear and anger in Pakistan, which has long battled distrust toward health workers, particularly vaccinators working to stamp out polio.

“The use of unsafe syringes might be one of the causes for spread of the disease, but the government is making all-out efforts to ascertain the exact cause,” Zafar Mirza, Pakistan’s top health official, said in a news conference at the time.

The doctor’s attorney told CNN at the time that his client “has been made into a scapegoat for the larger crisis in the region.”

In November, the New York Times reported that since April, more than 1,100 people had tested positive for HIV in a town of just 36,000 people — the vast majority of them small children.

Dengue

Mosquito larvae carrying dengue, a dangerous virus that causes a host of painful symptoms, do not need much water to breed. So when an outbreak occurs, it can be hard to slow its spread. People infected with the virus suffer immensely.

They develop high fevers and achy joints. They vomit, experience terrible headaches and often have pain behind their eyes. In severe cases, they can die.

This year, deadly dengue outbreaks around the world worried health officials and scientists, many of whom noted a link between climate changes and the prevalence of mosquito-borne illnesses.

In Honduras, more than 100,000 people contracted the viral disease, and about 175 died, the New York Times reported. In Nepal, an unprecedented outbreak of the disease infected 11,000 people between July and October. In the Philippines, about 100,000 cases of the virus were recorded in the first six months of the year, CNN reported. More than 1,000 people there have died.

Raman Velayudhan, who leads the dengue task force at the World Health Organization, told The Post’s Joanna Slater last year that there has been a “huge increase” in the number of cases worldwide.

“Unfortunately, things are a little grim at the moment,” he said.

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