Measles evolved from an ancient cattle disease as early as 3,000 years ago

A 1954 outbreak at a Boston boarding school allowed scientists to isolate the measles virus

While measles was described as early as the 9th century, humanity lacked the medical technology to fight the disease until the mid-20th century. Vaccine development from the Boston outbreak in the 1960s and 1970s led to one of the most effective inoculation campaigns in history.

Measles reached global transmission during the 15th- and 16th-century Columbian exchange

Devastating diseases like smallpox, influenza, measles, and other viruses were largely introduced into the Western Hemisphere beginning with the 1492 arrival of Christopher Columbus and the ensuing age of exploration.

The measles vaccine has saved an estimated 94 million lives since its introduction

Measles killed an estimated 2.6 million people globally in 1980, after the development of a vaccine but before its widespread dissemination. By 2014, that figure had dropped to an estimated 73,000.

Measles is one of the most contagious preventable diseases

The virus’s ability to persist in the air for up to two hours means an infected person could enter a room, leave, and two hours later infect someone else entering the room. Its location in the body’s upper respiratory tract also makes it easy for viral particles to be sneezed or coughed into the air.

A look at the 2025 measles outbreak in West Texas and surrounding areas

A measles outbreak in the summer of 2025 ultimately led to more than 900 cases and the deaths of two young children. The highly contagious virus requires vaccination rates near 95% to achieve herd immunity—the Texas outbreak spread through areas of significant mistrust of vaccines, including the area’s Mennonite community.

Measles symptoms range from fever to pneumonia and encephalitis

While less common, most measles-related deaths come from secondary conditions such as pneumonia (one to six cases per 100 patients) and encephalitis (one case per 1,000 patients). Blindness, which is rare, may arise from corneal ulceration.

A technical look at the measles virus and its life cycle

The measles virus is made up of a single strand of RNA, packaged inside an envelope that varies in shape and size. A negative-sense paramyxovirus—the same family as mumps—the virus is encased in proteins that help it attach to immune cells inside the body.

Before vaccines, there was 'variolation': what was it?

Before the technology behind vaccinations was discovered, some keen observers of medicine around the globe noticed how previous infections could impact future ones. Learn about the techniques early physicians used before they had vaccines.

Molecular evidence suggests the deadliest malaria parasite may be 100,000 years old

Plasmodium falciparum, the form of the parasite that kills the most humans, may date back 100,000 years, according to mitochondrial DNA analysis published in Science in 2003. It suggests that the parasite took off in humans about 10,000 years ago.

Why genetic similarities between humans suggest a past near-extinction event

Researchers have found that low genetic diversity among humans—even those on opposite sides of the planet—may result from a breeding population of as few as 1,280 adults, estimated to have existed 930,000 years ago. This genetic bottleneck may have resulted from a near-extinction or from a small population of human ancestors, from which we all descend, that broke off from a larger population.

Understanding R0, a measure of how contagious a pathogen is

The R0 value is a basic measure of how many people an infected person will transmit a pathogen to, on average. If R0 is less than 1, transmission dies out; if greater than 1, an outbreak is likely. Measles has one of the highest known R0 values at almost 18, meaning that after four transmission steps, more than 100,000 people could be infected.

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.

Lyme disease-causing bacteria predate any suspected biological weapons testing

Borrelia bacteria existed long before any US biological weapons program—or human presence in North America. One study comparing genomes of the bacteria behind Lyme disease collected samples of the bacteria over three decades and calculated that the bacterium has been in North America longer than humans, at least 60,000 years. Other work found related bacteria preserved in amber from millions of years ago.

Zoonotic diseases: Pathogens that jump from animals to humans

Such diseases may be caused by a variety of pathogens—viruses, bacteria, fungi, or parasites—and can originate in creatures ranging from ticks and mosquitoes to pigs and bats. Because they develop in animals and are often new to human immune systems, zoonotic diseases have severe consequences for public health.

What we know about aurochs, the ancestors of modern cattle

The relationship between humans and cattle is invaluable and longstanding. Evidence suggests cattle's wild, larger, and now-extinct ancestors, the aurochs, were also linked to early humans. Similarly valuable for their milk and labor power, yet significantly more threatening due to their size, aggression, and speed, auroch domestication was slow and complex. Discover new information about the fascinating ancestors of modern cows and the potential of re-introducing the species with selective breeding.

The invention of cheese likely came from a fruit fly landing in a pail of fermenting milk

The chance encounter around 5,500 years ago laid the groundwork for cultured milk products like yogurt and cheese. Over time, microbes evolved in tandem with goats, sheep, and wheat to give us the wide variety of cheeses that we enjoy today.

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.

Watch how viruses like Ebola can spill over from animals to humans—and vice-versa.

Up to 8% of the human genome consists of ancient viral DNA

Human endogenous retroviruses are remnants of infections that affected human primate ancestors millions of years ago and were passed on by infiltrating sperm and egg cells. Studies have shown that this DNA may play a role in immune responses and in placental formation.

Wastewater testing has detected genetic evidence of polio, triggering vaccine boosters

Sampling of wastewater in London in 2022 detected fragments of polio virus, suggesting a vaccine-derived version of polio may be circulating. No one became ill, but the finding did trigger calls for a renewed booster inoculation campaign.

Dinosaurs suffered from cancer, arthritis, and infections seen in modern animals

Using CT scans and advanced pathology techniques, paleopathologists have identified respiratory illnesses, malignant osteosarcoma, and other diseases in dinosaurs. The research has helped show how many of these ailments are not exclusively modern phenomena.

Bees evolved from meat-eating wasps that became vegetarian

After flowering plants first appeared approximately 140 million years ago, some wasp diets would have changed as they consumed pollen-coated insects that would visit these plants. Bees that branched from these wasp species also developed long tongues to slurp nectar and ultraviolet vision to identify flower patterns unseen by humans.

Food allergies were first documented more than 4,000 years ago

Although food allergies are on the rise in modern times, they have been documented in written records for thousands of years. More than 3,000 years ago, Chinese emperors advised patients to avoid certain foods, and Hippocrates noted in his work that food could cause serious harm to certain individuals, and even lead to death.

LSD was derived from natural compounds produced by the ergot fungus

Ergot is a fungus that slowly infects and replaces individual grains on grasses, including rye and wheat. Ingesting ergot can cause ergotism, a form of poisoning with symptoms—including headaches, hallucinations, gangrene, and convulsions—varying by season and geography. This grain was used for medicinal purposes as early as the 1500s.

Biologist Richard Dawkins coined the term 'meme'

His 1976 book "The Selfish Gene" proposed that units of culture could be replicated, passed on, and evolve as they were transmitted, similar to human genes. He called this unit a "meme," to be pronounced like "cream."

Listen to what it was like living as a medieval leper

This podcast uses paleopathological and anthropological findings to reconstruct what it was like for people diagnosed with leprosy in medieval times on the Eurasian continent. If a town lacked a leprosarium—an isolated leper asylum or colony—or the suspected leper was a foreigner or a Jew, which would make them ineligible for leprosarium admission, they'd be expelled.

Genetic engineering has accelerated millennia of altering various crops' genes

Although farmers have long cross-bred crops to obtain plants with specific colors, sizes, and other characteristics, these processes took significant time. Today, genetic modification in agriculture involves scientists altering an organism's DNA for various purposes, including enhancing pathogen resistance, removing allergens, and delaying spoilage.

An Ebola vaccine was developed during the 2018 west African Ebola outbreak, but the 2026 Ebola outbreak is with a different species of the virus, not the one that the vaccine is approved to treat.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

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.

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

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.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

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

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.

Learn more about the history of fireworks, which dates back to an accidental invention during an alchemist's quest for information about immortality.

Elk Cloner, the first computer virus to spread in public, was written as a practical joke by Richard Skrenta, a Pittsburgh high school student.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

View the ten deadliest tornadoes in US history.

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

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

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