Two diseases humanity has ended, and the one that is nearly gone
Smallpox is gone. Rinderpest is gone. Guinea worm went from an estimated three and a half million cases a year to fifteen in 2024. How it was done, and who did it.
Most news is a record of what went wrong today. This piece is the other half of the record: three diseases that people decided to end, and did, or very nearly have. None of this is new. All of it is checkable, and that is the point of the Progress desk.
1. Smallpox: the only human disease ever eradicated
What got better. A virus that killed about three in every ten people it infected, and left many survivors blind or scarred, no longer exists outside two laboratory freezers.3 The World Health Organization estimates that smallpox killed around 300 million people in the twentieth century alone.1 Nobody has caught it naturally since 1977.
Where and when. Everywhere. The last naturally occurring case was a hospital cook in Merca, Somalia, in October 1977.1 On 8 May 1980 the World Health Assembly, the governing body of the WHO, declared the disease eradicated.2
The number. From an estimated 10 to 15 million cases a year in 1967, when the WHO began its intensified campaign, to zero in 1977.1 Two sealed stocks of the virus remain, one in the United States and one in Russia, for research.1
Who did it. A vaccine that had existed since Edward Jenner's experiments in 1796, and a strategy that did not: instead of trying to vaccinate everyone, health workers hunted for cases, isolated them and vaccinated everyone around them, a method called ring vaccination.3 The campaign was run by the WHO and carried out by national health services and tens of thousands of local workers who went village to village with photographs of the rash, asking whether anyone had seen it.
2. Rinderpest: the first animal disease eradicated
What got better. Rinderpest, or cattle plague, was a viral disease of cattle, buffalo and many wild grazing animals that killed most of the herds it reached. For farming families whose wealth and food were their animals, an outbreak meant famine. In 2011 it became the second disease in history, after smallpox, to be declared eradicated from the planet.4
Where and when. The last confirmed outbreak was in Kenya in 2001.4 The World Organisation for Animal Health recognised every country as free of the disease on 25 May 2011, and the Conference of the UN Food and Agriculture Organization declared global eradication on 28 June 2011.4,5
The number. When rinderpest reached Africa in the 1890s it killed the great majority of cattle across much of the continent, and the hunger that followed killed people in large numbers.4 Today the count of cases is zero, and has been for more than two decades.
Who did it. Veterinarians, with a heat-stable vaccine that could travel without refrigeration, and a coordinated programme, the Global Rinderpest Eradication Programme launched by the FAO in 1994, which coordinated the national and regional campaigns that trained community animal health workers to vaccinate herds and to find and report the last outbreaks in remote herding areas.4
3. Guinea worm: from millions to a handful
What got better. Guinea worm disease is caused by a parasite swallowed in unfiltered water. About a year later a worm up to a metre long emerges slowly through the skin, usually the leg; it is agonising, it disables people for weeks during planting and harvest, and there is no vaccine and no medicine for it.7 It is now close to becoming the first parasitic disease, and the first disease without a vaccine or a drug, to be eradicated.
Where and when. In 1986, when the Carter Center took on the campaign, the disease was found in 21 countries across Africa and Asia.6 From 2022 to 2024 the human count stayed in the teens each year, and the remaining difficulty is infection in animals, especially dogs, which can carry the parasite between seasons.6,7
The number. An estimated 3.5 million human cases in 1986. Thirteen in 2022. Fourteen in 2023. Fifteen in 2024.6 The Carter Center announces each year's count in January as a provisional figure, confirmed by the countries concerned later in the year. We will add the next year's count only when a second person has checked it against the Carter Center's own release.
Who did it. No laboratory breakthrough was involved. The tools were a cloth or pipe filter for drinking water, a larvicide for ponds, containment of every patient so the emerging worm never touches water again, village volunteers trained to teach prevention, and a cash reward for anyone who reports a case.6 The programme is led by the Carter Center with the WHO, UNICEF and national health ministries.6
What the three have in common
The same recipe appears each time. A precise definition of a case. Surveillance good enough to find every one, which means rewarding the people who live where the last cases are for reporting them. A tool that breaks transmission, even a humble one. Patience measured in decades, not budget cycles. And money that did not stop when the numbers got small, because the last cases are the most expensive to find.
That recipe is not secret, and it is not finished with. It is the reason the Progress desk exists: to notice, with sources, when it works.
Checked against the WHO, WHA, FAO, WOAH and Carter Center documents listed below on 6 November 2026. Every figure above comes from one of them; where an estimate is an estimate, we have said so. This piece has not yet been checked by a second person.
Sources
- World Health Organization, "Smallpox" (health topic page) and "Commemorating Smallpox Eradication: a legacy of hope", 8 May 2020, who.int.
- World Health Assembly resolution WHA33.3, 8 May 1980, declaring the global eradication of smallpox.
- US Centers for Disease Control and Prevention, "History of Smallpox" and "Smallpox: Signs and Symptoms", cdc.gov.
- Food and Agriculture Organization of the United Nations, "Rinderpest" (fao.org), and FAO Conference resolution 4/2011, 28 June 2011, declaring global freedom from rinderpest.
- World Organisation for Animal Health (founded as the OIE), resolution 18/2011, 25 May 2011, recognising all countries and territories free from rinderpest, woah.org.
- The Carter Center, "Guinea Worm Eradication Program" and its annual case counts (an estimated 3.5 million cases in 21 countries in 1986; 13 human cases in 2022; 14 in 2023; 15 in 2024), cartercenter.org.
- World Health Organization, "Dracunculiasis (Guinea-worm disease)" fact sheet, who.int.
Corrections. None yet. If you find an error, write to [email protected]. Every correction is logged here with its date.