We're in the middle of a decadeslong cholera pandemic

Cholera went global thanks to global trade

The first cholera pandemic grew from an outbreak in India, in 1817. Scientists suggest it spread from there throughout the continent and onward to Africa, Russia and Europe through the poop of traders.

1 in 4 people around the world don't have access to clean water

Poor water sanitation puts people at risk of acquiring this diarrheal infection. Cholera infections are on the rise due to extreme weather events and conflict. In recent years there have been cholera outbreaks in locations that hadn't seen the disease in many years, including Haiti.

More than 4,000 people died from cholera in 2023

This global health threat sickened more than half a million people in 2023 and killed 4,007 people. That's a 71% increase in deaths as compared to a year earlier. (Report only offered in PDF format.)

Extreme weather conditions heighten cholera risks in settings like refugee camps

Runoff from sewage—exacerbated by situations like flooding or extreme rains—heightens this threat. Increasing temperatures also create the ideal conditions for the bacteria to reproduce, increasing transmission risks.

About 20% of people infected with cholera have severe symptoms

That's according to studies from outbreaks in Bangladesh. Most people who contract the disease have mild or moderate symptoms, or none at all. Yet anyone infected with the disease-causing bacteria can shed the pathogens in their feces for a few days, or even up to around 10, seeding the environment with bacteria.

Historically, cholera has repeatedly disrupted the Hajj for Muslims

Outbreaks of the disease throughout the 19th century and the beginning of the 20th, killed thousands of religious pilgrims as they sought to complete this obligatory pilgrimage.

See how cholera spreads in a community

This animated video offers a comprehensive look at how cholera spreads. It makes clear why it's so difficult to stamp out this disease in communities around the world. It also details what steps can help control cholera.

There's a goddess in South Asia worshipped for her protection against cholera

Both Hindus and Muslims in certain parts of South Asia pray to Oladevi, also known as Olabibi, to help protect against cholera. People also pray to this goddess for protection against epidemics more broadly.

Cholera vaccines can protect people from disease for months—or even years

There are three recommended cholera vaccines on the market. The number of required shots and the period of protection they provide vary, but each of them can be life-saving.

Climate shifts are projected to cause more cases of food poisoning

Research published in 2024 suggests that with more severe heatwaves and natural disasters, scientists expect there to be a rise in foodborne disease, especially in Africa and Asia. Already, there are an estimated 600 million food poisoning cases and 420,000 deaths annually. Diarrhea is the most common cause of those deaths.

Maryland required cholera researchers to fly a yellow warning flag—signifying quarantine dangers in the 1970s

University of Maryland Hospital researchers intentionally infected volunteers with the cholera bacterium in the late 1970s to further their understanding of the disease. They proceeded with this work following the recommendation of a US government panel. (Some users may encounter a paywall.)

Since 1600, the longest stretch without an outbreak that killed 10,000 was four years

We think of pandemics as unlikely events, but disease outbreaks are surprisingly common. Over the past 400 years, the longest stretch without an outbreak that killed at least 10,000 people was just four years. The next pandemic can't be precisely known, so experts and policymakers focus on preparation.

Drug-resistant infections worldwide have increased by about 65% since 2000

Since 1990, antibiotic resistance has claimed at least one million lives annually and is projected to account for 39 million deaths between now and 2050 if current trends continue. The expanded use of antibiotics, particularly in agriculture, combined with a slowing pipeline of new drugs has led to the crisis.

The wonderfully named Vibrio diabolicus is a cousin of the cholera-causing bacterium

This bacterium, which belongs to the same genus as the cholera bacterium, was initially isolated from deep-sea hydrothermal fields. It was sampled from water that was scooped up during a French-American cruise in October 1991.

See what regions report new leprosy cases

This graphic shows the burden of leprosy by region for 2023, based on data provided from the World Health Organization, which collates this information. Southeast Asia leads in the number of cases by region. (Some readers may experience a paywall.)

South Asia and sub-Saharan Africa are most at risk from falling pollinator numbers

Researchers at the Harvard T.H. Chan School of Public Health found that declines in pollinator populations would lead to higher rates of nutritional deficiencies, particularly in developing nations. Nations with large populations, such as China and India, would also be significantly impacted.

Paris and Boston were redesigned partly to combat cholera's spread

Georges-Eugène "Baron" Haussmann, who oversaw Paris's redesign in the 1800s, replaced many of the city's narrow streets with wide boulevards. This was done at least in part to bring more air and light into the city to help control cholera. Architect Arthur Gilman redeveloped Boston's Back Bay to similarly combat cholera, among other reasons.

'Tomato flu' outbreak in India turned out to be HFMD

An illness initially dubbed "tomato flu" in 2022 that sickened children in Kerala, India, with symptoms typical of hand, foot, and mouth disease turned out to be that—not a new ailment. A letter published in the prestigious journal The Lancet had initially described the illness as "a new virus" but at least some of the children ultimately tested positive for one of the viruses that causes HFMD, so it wasn't a new condition after all. (Some users may encounter a paywall.)

See this diverse list of vector-borne diseases

Human illnesses caused by parasites, viruses, and bacteria, and transmitted by a living organism—often small, bloodsucking ones like mosquitoes, ticks, and sandflies—are known as vector-borne diseases. That carrier is called a vector. These diseases disproportionately affect the poorest populations in tropical and subtropical areas.

Why Haiti is in crisis

Haiti’s crisis is decades in the making. Burdened by colonial debt, political instability, and economic collapse, the country faces worsening conditions. Gangs now control much of Port-au-Prince, hunger has reached near-famine levels, and violence continues to escalate. Here’s how Haiti got here—and what’s happening now.

This real-time tracking of the hantavirus cruise ship outbreak in May 2026 offers a unique glimpse into the global reach of the outbreak and whether the virus sickened passengers and their communities around the world.

How the World Bank's pandemic bonds were triggered during COVID-19

In 2017, the World Bank raised a chunk of emergency funds through bonds to help developing countries cover funds in the event of a pandemic. Had no pandemic occurred, investors would have received returns of 6% to 11%. But the global pandemic meant they lost all their money.

Eight demographic trends to watch

This list highlights eight demographic trends expected to shape the world in the coming decades. The world’s population is projected to hit 9 billion in 2037. In that time, India will overtake China in population, and the Democratic Republic of...

COVID-19 disruptions revived ancient chinampa farming in Mexico City

When the pandemic disrupted food supply chains, chinamperos—farmers who cultivate the Aztec-era “floating gardens” built atop shallow lakebeds—shifted to direct sales in the city, boosting their visibility and reconnecting residents with a longstanding local agricultural tradition.

See how Ebola tore through Guinea, Sierra Leone, and Liberia in 2014-2016.

The Rohingya refugee emergency at a glance

This interactive website provides an in-depth dive into the Rohingya refugee emergency. According to the UNHCR, the influx of Rohingya refugees to Bangladesh is one of the largest and fastest-growing refugee crises in decades. Since 2017, an...

Cities bore the brunt of the migrant surge in the 2020s

During the 2022-24 migration surge, cities such as New York, Chicago, and Denver faced shelter overcrowding, strained public services, and housing shortages—while the upfront costs fell almost entirely to states and cities.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Some researchers have labeled nomophobia, the fear of being without your phone, as 'the phobia of the 21st century.'

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Fireworks-related ER visits are on the rise—in 2024, they increased by 52% as compared to the prior year.

A century of Billboard issues documenting the evolution of popular music.

The Russia-Ukraine conflict is the largest ground war in Europe since World War II in casualties, forces mobilized, and displacement of civilians.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

The US first hosted the World Cup in 1994, a tournament that lives in soccer infamy for its poor planning and the murder of Colombian player Andres Escobar, who'd accidentally scored on his own net.

Poison ivy is in the same family as mangoes, cashews, and pistachios—and they all produce oily urushiol in their raw, unprocessed state—but they are typically prepared in ways to avoid causing human discomfort.

Fast-casual restaurant Chili's is experiencing a resurgence, with its parent company recently reporting a nearly 32% increase in sales, thanks to passionate Gen Z fans on TikTok.

In 2019, a laptop loaded with six of the worst malware in history and described as 'an exhibit of historical weaponry' sold for $1.3M.

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

In 2026, Finland was named the world's happiest country for the ninth consecutive year based on its wealth, social safety network, and high life expectancy, among other factors.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

One of the most famous portraits ever taken is 'Afghan Girl' (1984) by Steve McCurry, yet the subject Sharbat Gula went much of her life without being identified or benefitting from the image's success.

US consumers collectively owe more than $1T to credit card companies—almost as much as they owe in auto loans.