Sandra Mwayera wailed as her older brother slouched next to her in the back seat of a car — he had died from cholera as he waited for treatment among dozens of others outside a hospital in Zimbabwe’s capital, Harare.
“My brother! My brother! Why have you abandoned me?” she pleaded. “Come back, please. Come back!”
In neighboring Zambia, inside the 60,000-seat National Heroes Stadium in the capital, Lusaka, rows of gray cots lined rooms at a makeshift treatment center where 24-year-old Memory Musonda had died. Her family said they were not informed until four days later — the government buried her, and they have yet to locate her grave.
Ms. Musonda’s uncle, Stanley Mwamba Kafula, said the family was “disturbed” and “heartbroken.”
Active outbreaks of cholera, a waterborne bacterial disease, are now raging in five countries in central and southern Africa, ranging from as far north as the Democratic Republic of Congo, and down to Mozambique.
The epidemic has spread over the past two years, infecting more than 220,000 and killing more than 4,000 people in seven countries. This is the deadliest regional outbreak in terms of cases and deaths to hit Africa in at least a decade, said Dr. Patrick Otim, who oversees the cholera response for the World Health Organization in Africa. Public health workers in Africa say it is rare to see so many cases in so many countries at the same time.
Cholera cases in Africa had actually been on a downward slide and hit a low in 2020, he said. But then came an uptick in West Africa in 2021, followed by the current outbreak in the southern part of the continent.
Two countries — Zambia and Malawi — have reported their largest cholera outbreaks ever, while Zimbabwe has seen its second-highest number of cases on record. Of the 19 countries in the African Union that have reported deaths and cases over the past year, nearly three quarters of the cases have come from southern Africa, according to the Africa Centers for Disease Control and Prevention.
“The cholera situation in southern Africa — particularly in Zimbabwe and Zambia — is dire,” said Dr. Mounia Amrani, the southern Africa medical team leader for Doctors Without Borders.
The devastation is linked to increasingly ferocious storms, a shortage of vaccines, and poor water and sewer infrastructure, public health experts said.
Representatives from 15 nations in the Southern African Development Community have agreed to a collective mobilization that includes investing in vaccine production and distribution, collaborating on surveillance for the illness across borders and developing reliable water and sanitation systems.
Zambia has been hit the hardest by the disease and is experiencing its deadliest outbreak on record. Since October, more than 650 people have died and more than 18,500 have been infected, though cases and deaths have slowed since they peaked in January. Five deaths were reported in the 24 hours leading up to Monday, compared with the more than 15 fatalities that were recorded daily last month. Schools reopened on Monday after a delay of about a month.
Still, there are worrying signs. The outbreak was initially confined to the capital of Lusaka but has since spread to nine other provinces. The death rate of 3.5 percent is far higher than the 1 percent rate that health experts say is typical. Dr. Otim said about half of the deaths in Zambia occurred at home rather than at health centers, an indication that people either denied or were unaware they had cholera.
Doctors Without Borders has deployed 50 health workers to Zambia and 30 to Zimbabwe to help manage the outbreaks.
Even as public health and government officials race to battle the outbreaks, the Africa C.D.C. warns of the potential for a difficult situation ahead: Above-normal rainfall is projected across much of the region through this month, the type of weather that floods communities, destroys infrastructure and increases the risk of cholera transmission.
People typically are infected with cholera when they ingest water that has been contaminated by human waste. The surest way to prevent the disease is to keep water sources for drinking and washing separate from sewage, public health experts say.
Many communities across southern Africa are plagued by poor water and sewer infrastructure. Residents often rely on shallow pit latrines as toilets, and, without piped water, use streams or lakes for drinking and washing. This presents a significant risk of cross contamination, especially when there are heavy rains and floods.
One of the main commitments made by leaders of the Southern African Development Community was to invest more in developing resilient water and sewer systems.
“If we don’t address the water, hygiene and sanitation issues, we will not stop the cholera outbreak,” Dr. Otim of the W.H.O. said.
Vaccination is also a major issue. A surge in cholera outbreaks globally in 2021 and 2022 depleted the stockpile of vaccines, Dr. Otim said, and there is only one manufacturer that produces the cholera vaccine at a global level. Last year, about 37 million doses were produced, even though the demand was about 60 million, he said.
Dr. Amrani said that cholera had received less attention than other diseases from the pharmaceutical industry, also contributing to the vaccine shortage.
While longer-term solutions such as creating better water infrastructure and increasing vaccine production may take time, organizations like Doctors Without Borders and the W.H.O. are helping countries across the region tend to the immediate problem of treating suffering patients. They are providing hydration treatments, medical workers and supplies.
At a treatment facility set up at a school in a dense suburb of Harare, nurses wearing latex gloves tended to patients splayed on cots. There were groans and cries, and some patients propped themselves uncomfortably on benches, waiting to be treated.
“I’m dying! Please, I’m dying!” one woman at the school shrieked as nurses tried to put intravenous tubes into her hands to give her fluid for hydration. “What shall my children do? Who shall take care of them?”
On a recent morning inside the Sally Mugabe Central Hospital in Harare, where Ms. Mwayera’s brother had died outside in the car, a nurse delivered bad news to members of another family waiting in a hallway. Jethro Nguweni, 52, had lost his battle with cholera.
“What shall I do?” his wife, Melia Nguweni, sobbed, removing her head scarf and throwing it down. “My husband is gone. He has left me.”
Collins Chilumba Sampa contributed reporting from Lusaka, Zambia.