In 1865, Hawaii's king authorized forcible removal, quarantining of those with leprosy

Read excerpted accounts from some of the 8,000 residents with leprosy on Moloka'i

Accounts preserved by the Kalaupapa National Historical Park describe how residents felt about being sent to live in this remote location and knowing they would never be allowed to leave. In 2012, 20 residents with the disease continued to voluntarily live in the area.

America had a national leprosarium—a leper colony—in Louisiana until 1999

Public health officials forcibly sent those diagnosed with leprosy to the Louisiana Leper Home in Carville, first founded in 1894. Listen to an interview about this site, its evolution, and how its residents advocated for themselves—including regaining the right to vote.

Hawaii lived under martial law for nearly three years after Pearl Harbor

After the attack, Hawaii was placed under sweeping military rule—curfews, censorship, warrantless arrests, ID papers, and mass detentions transformed everyday life. More than 2,000 people were arrested within 48 hours of the attack, and the islands remained under martial law for nearly three years.

See examples of leprosy in the Bible—a broad term for skin ailments in ancient times

People afflicted with leprosy in the Bible may have had a range of different skin diseases, rather than what's clinically diagnosed as Hansen's disease (leprosy) today. In the Bible, as in many traditional societies, those with the disease were often considered unclean or sinful.

81% of Florida's leprosy cases occur in central Florida, raising concerns

Researchers noted in 2023 that about one-fifth of new US leprosy cases were reported in the central part of the Sunshine State. What's more, about a third of the new US cases overall appear to have been acquired locally, raising questions about whether the disease is now naturally occurring in parts of the southeastern US.

About 95% of people are naturally immune to leprosy

Contracting it requires prolonged contact with someone with the disease, meaning you'd have to be living with them. You cannot get leprosy from hugging someone with leprosy or sitting next to them. It's not known to pass from mother to fetus. The risk of transmission from armadillos is also likely low, but people should avoid touching wild animals for general safety.

Grosse Île, the quarantine island of the Port of Quebec

As tens of thousands of Irish emigrated to North America to escape the Great Famine in the mid-19th century, many port cities set up quarantine areas amid an epidemic of cholera. In Quebec City on the St. Lawrence River, one island became a mass graveyard where over 3,000 Irish immigrants died over a decade as they waited in quarantine. Listen to the history here.

Wild chimpanzees have been spotted with leprosy lesions

In research published in 2021, scientists reported discovering cases of leprosy in wild chimpanzees from Guinea-Bissau and the Ivory Coast—marking the first time the disease has been found in any nonhuman species in Africa. They confirmed that leprosy was the cause of the deformities by testing the animals' poop for the presence of the disease-causing bacteria.

Why Hawaiians live longer

Hawaii has the longest life expectancy at birth out of all 50 states, according to the US Centers for Disease Control and Prevention. Key factors include strong healthcare, lots of sunlight, and active lifestyles.

Hippocratic doctors treated severe mental illness with the poisonous plant hellebore

Since symptoms like hallucinations were believed be due to an imbalance of black bile, yellow bile, blood, and phlegm, the treatment at the time was to bring those humors back into balance. That meant standard treatments could include bleeding a patient or using substances like hellebore to induce vomiting or diarrhea.

Explore what it's like Inside a patient isolation unit

Containing a contagious disease like Ebola requires strict protective measures. There are several specialized medical wards to contain deadly infectious diseases at hospitals across the U.S. Emory University has one such unit, where 4 patients were treated during the 2014 outbreak.

HFMD was first reported in 1957 in New Zealand

The first clinical report involved eight kids with the characteristic sores in New Zealand, and then in the years that followed there were dozens more cases there and also reports of outbreaks in England and Scotland, among other settings, including the US.

The cholera bacteria was first isolated in 1854—but the discovery was largely ignored

The pathogen was isolated by the Italian physician Filippo Pacini in Florence, Italy, though his discovery was largely ignored in favor of the popular miasma—bad air—theory of disease at the time. The pathogen was separately isolated about three decades later by German microbiologist Robert Koch.

Fungi have been used to restore island habitats in the central Pacific

After removing 1.5 million invasive coconut palm trees and eradicating the black rats that fed on them, as well as seabirds and crabs, conservationists working with the US Fish and Wildlife Service identified areas where fungi could be transplanted to provide nutrients to native trees. These trees serve as nesting sites for seabirds whose guano nourishes coral reefs.

Explore what it's like inside a patient isolation unit, used in situations such as treating a patient or suspected patient with Ebola.

Hawaii formed from oceanic plate movement over a hot spot in the mantle

Abnormally hot magma rose through the crust and emerged from the seafloor, where it cooled and piled onto layers that became tall enough to form an island. As the plate moved, the existing island moved away and a new one formed over the hot spot, repeating for each Hawaiian island.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

The board game Candyland was invented for children quarantined in polio wards.

That time General Ulysses Grant barred Jewish residents from the war zone

In 1862, General Ulysses S. Grant issued an order that banned all "Israelites" (meaning Jews) from a military zone consisting of parts of Tennessee, Kentucky, and Mississippi. After much outcry, the order was rescinded by President Abraham Lincoln and Grant feebly explained it was a misunderstanding. Learn more about this odd bit of history here,

The iron lung—a simple mechanical ventilator—was first used to treat polio

These breathing devices, developed in the late 1920s at Harvard, were used to treat polio patients with breathing difficulties. Watch this video describing how these negative pressure devices work.

Deinstitutionalization in the 20th century unintentionally led to the incarceration of schizophrenia patients

Activism to shut down problematic asylums in the mid-20th century led to the community release of many patients with severe mental illnesses, including schizophrenia, but without adequate support, this deinstitutionalization in the 1960s and 1970s led to a significant increase in patients with schizophrenia ending up in prisons and homeless shelters.

Patient H.M. revealed that the hippocampus was responsible for memory formation

Henry Molaison became a landmark case in psychology after surgery removed large portions of his hippocampus, leaving him unable to form new memories. Upon his death, Molaison's brain was sliced into 2,401 sections and digitized for research.

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

The Indian Removal Act of 1830 forcibly displaced tens of thousands of Native Americans

Signed by President Andrew Jackson, the act authorized the federal government to negotiate treaties relocating Native nations from their Southeastern homelands to lands west of the Mississippi, often by force.

Magic Johnson's announcing he had HIV changed public perception of the disease

When Lakers superstar Magic Johnson announced he had HIV in 1991, the disease was highly misunderstood. Commissioner David Stern had behind-the-scenes conversations with Johnson about publicly handling his eventual announcement, leading to the start of the condition's destigmatization.

Approximately 10% of American K-12 students are enrolled in private schools

Around 75% of those students attend religiously affiliated institutions. In Hawaii and Washington, DC, 19% of students attend private schools, the highest enrollment percentages in the country.

The Hays Code limited the ways horror films could scare audiences

Beginning in 1930, the Hays Code laid out a strict set of guidelines for Hollywood filmmakers to prevent films that might corrupt those with a “susceptible mind.” That meant no graphic violence, no sexual relations outside of marriage (or of a homosexual nature), and no interracial relationships, among other dictums.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

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

70 years ago today, city officials in Santa Cruz, California, banned rock 'n' roll to protect its youth from corruption after witnessing a 'provocative' concert the night before.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

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

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.

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

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.

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.

Against his wishes, Albert Einstein's brain was removed before his cremation, and the pathologist responsible stored it for decades in mason jars within a beer cooler.

During the French Revolution, a botanist's letter asking about "dear Rhus" (poison ivy) was intercepted, leading authorities to suspect he was conspiring with the Russians.

The concept of phantom limbs, the perception that amputated limbs are still present, dates back to a French military surgeon in the 16th century.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

The story of Dollree Mapp, whose legal challenge over her 1957 conviction for possessing "obscene material" led to a major strengthening of the Fourth Amendment

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

The United States has had a tumultuous relationship with Cuba since its 1959 revolution, highlighted by a nuclear crisis and a decades-long trade embargo.

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

Doctors differentiate between a phobia and fear by asking patients whether their fear interferes with their day-to-day activities.

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by over 1.5 million Muslims.

Mark Twain spent decades feuding with the US Postal Service, convinced its costs and regulations were bureaucratic overreach.

In 2025, four executives from large tech companies were given positions in the US Army Reserves—including Palantir Chief Technology Officer Shyam Sankar, which reinforced Palantir's ties with the US military and its role as a leading defense partner.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

See this overview of the firework rules across all 50 states, ranging from a complete ban on non-professional fireworks in Massachusetts to states with more lax rules like Indiana.