No one is tracking the total number of animals used for research across US labs, though partial data without any rodents puts the 2024 count above 775,000 animals, including some 40,000 dogs and 100,000 primates.

Scientists William Russell and Rex Burch proposed in 1959 that when it comes to animal testing, there should be 'three Rs'—replace animals wherever possible; reduce their numbers; refine how they're treated.

US federal researchers are blocked from putting certain human cells in animals

In 2015, US policymakers put a halt to any government-funded work that would insert human stem cells into animals. The reasoning was that human cells might spread through the animal's body and perhaps to its brain, blurring the line between humans and nonhumans. The ban remains in place today even as gene-edited pig parts are being placed in humans.

Discover the latest information on US measles cases from official outbreak tracking figures.

Minorities are largely underrepresented in medical research, which compromises our understanding of how conditions and treatments may affect various populations, but recent efforts, like the African Ancestry Neuroscience Research Initiative and new genome research studies, are seeking to close that gap.

In 2024, the US had more organ transplants than ever before—besting the 2023 record

More than 48,000 organ transplants were performed in 2024, and about 46,630 were performed in 2023. These record highs are illustrated here as part of data from 1988 to partway through 2025. Kidneys, livers, and the heart remain the most common transplanted organs. (Some users may encounter a paywall.)

As of 2022, about 40% of scientific research aimed at generating new knowledge has been funded by the federal government—a percentage that has decreased from a high of 72% in 1967.

At one point in the 20th century, more than a million Americans had pet monkeys

This choice to domesticate monkeys proved to be trickier than expected, and thus isn't a very appealing option for humans. Monkeys breed more slowly than other animals, while also being susceptible to diseases and challenging to contain.

The US federal government employs roughly 3 million people

Tracking began in 1939, when the federal workforce consisted of about 1 million people. The total peaked in 1990 at 3.4 million, and hit a recent low in 2014 at 2.7 million.

The US military, concerned about potential deployments worldwide, has long funded experimental hantavirus vaccines and therapies.

Collaborations between the military, biotech, and academic researchers led to an experimental antibody treatment for the Andes hantavirus strain—the one that more readily passes between humans. As of spring 2026, it had only been tested in animals. The US Army has also tested a potential hantavirus vaccine in people. It published early findings in 2023 that seemed promising, eliciting some immune system response. (Some users may encounter a paywall.)

About 250,000 patients accessed assisted reproductive technologies in 2022

In 2022, 251,542 patients tried assisted reproductive technologies—most commonly IVF—resulting in more than 98,000 infants. Those children represent around 2.6% of the babies born in the US.

Explore US public health data

This resource tracks key US health metrics, including mortality causes, child survival rates, and life expectancy comparisons, to inform future health improvements, with regularly updated global estimates.

Most of the 86,000 consumer chemicals registered with the US EPA have never received rigorous toxicity testing, though not all those are still in current use.

Scientists can suck animal DNA from the air

A look at how researchers filtered the air around two zoos and identified genetic material from dozens of species, a technique that could help track and conserve wildlife.

Rabies kills more than 50,000 worldwide each year

Rabies transmission to humans typically comes from an infected animal, and death was very common before recent protocols were developed (post-exposure prophylaxis). The virus is neurotropic, which means it has an affinity for nerve tissue, and moves quickly from broadly infecting the body to destroying the brain.

As of 2023, there are about 1.1 billion objects stored in 73 of the world's largest natural history museums, but only about 16% of specimens are available in digital archives.

Countries tried to curb plastic waste, but the US keeps shipping more

Data show that American exporters continue to ship plastic waste overseas, often to poorer countries, even though most of the world has agreed to not accept it.

Explore a map of data centers worldwide, numbering over 12,250 as of August 2026, with over 4,500 in the US.

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

Our World in Data's COVID-19 tracker, with global case, death, and vaccination data for every country, though updates to the dataset ended in 2024.

More than 39 million people are expected to die from antimicrobial resistance by 2050

In 2024, researchers published an incredibly detailed study aimed at predicting the real-world impact of antimicrobial resistance over the next 25 years. The key findings were clear: the superbug crisis is poised to get much worse and needs to be addressed. This article offers a clear, concise overview of the study, which was published in The Lancet.

How political campaigns use your data

What do campaigns know about US voters, and how do they use that information to shape their strategies during elections? US political campaigns base their strategies and tactics on data collected from more than 200 million voting-age Americans. This visualization by Reuters breaks down how data firms create national databases of voter files, collecting information from a variety of sources to create detailed voter profiles and how political campaigns use that data.

Murder rates spiked in the US after COVID-19, and then declined in 2023

Criminologist and former investigator Jillian Peterson says whether a murder is solved in the US is nearly up to the flip of a coin, with the clearance rate for murder cases being about 50%. The US, which has more guns than citizens, has about roughly five gun homicides per 100,000 residents, resulting in the 28th-highest rate of deaths from gun violence compared to the rest of the world.

Roughly 80% of US antibiotics sold each year go to agricultural use

Antibiotics have long been used in agriculture to treat diseases in animals and plants. However, antibiotics are also often misused, to treat non-bacterial diseases, to encourage growth in animals, and more. This expansive use of antibiotics has become one of the primary sources of the emergence of new superbugs.

As of 2023, more than 130 nations have enacted bans or restrictions on plastic items, starting with Bangladesh's ban on plastic bags in 2002.

Nearly 99% of the Smithsonian's specimens are hidden in high-security

At the National Museum of Natural History, nearly 99% of its 147 million specimens are stored in secure research collections rather than on display, where they are actively used for scientific work ranging from tracking invasive species to improving aviation safety.

Pig-to-human transplant work has raised concerns about donor pigs' living conditions.

The Dog Aging Project uses information from over 50,000 dogs to explore longevity

The study gathers health, lifestyle, and genetic data to understand what helps dogs live longer, healthier lives. Findings could also provide human health insights due to our shared surroundings and biology.

Measles cases in the US reached a 35-year high in 2026 as vaccination rates dropped.

Hormone and peptide compounds imported from China soared in 2025

US customs data indicates that these imports doubled to $328M in the first three quarters of 2025, from $164M in the same period of 2024. The imports include GLPs, among other products. (Some users may experience a paywall.)

American beer, by the numbers

This statistics-focused resource breaks down the shape of the beer industry in the US, outlining the amount of beer produced by American breweries, the state cranking out the most beer, and the states with the most breweries per capita.

Dozens of US women in labor turned away from hospital between 2022 and 2024

An Associated Press analysis of federal hospital investigation data concluded that more than 100 pregnant women in medical distress were turned away from emergency rooms or treated negligently since 2022.

In 2025, almost 90% of global shipments of humanoid robots came from Chinese companies, led by Unitree and AgiBot, with over 5,000 units each.

The US FDA considered mitochondrial replacement therapy during 2014 hearings

An agency committee assessed if this approach could have undesirable ripple effects across multiple generations and whether a clinical trial involving this approach would be appropriate. As of 2026, the US has continued to prohibit this procedure though it is legal in other settings including the UK and Australia.

Food poisoning investigations have led to more than 1 billion pounds of food recalls

PulseNet is the US government’s real-time foodborne illness tracking system for leading causes of food poisoning. There, a network of labs and scientists share DNA sequences for pathogens collected from contaminated food and also from sickened individuals, looking for patterns in the pathogens’ genome sequences that will help them hopefully finger a certain food, warehouse, producer, or restaurant.

The US FDA recently tried to regulate the expanded prenatal genetic tests

The agency proposed a new rule in 2023 to make it explicit that these types of tests are devices under existing law and clarify that that the agency could move to regulate them. They finalized a regulatory change in 2024 that added the words "including when the manufacturer of these products is a laboratory" to an existing law, but a federal district court vacated that edit in March 2025—returning the law to as it was before.

40% of Americans didn't read a book in 2025, with 19% of adults responsible for 82% of the country's book reading.

By 2028, data center power consumption may equal 22% of US households

Date from 2023 suggests that data centers accounted for around 4.4% of US electricity consumption, with new facilities supporting the AI boom consuming more power than the state of New Hampshire annually. However, the energy impact of individual use varies widely depending on the prompt and AI model. (Some readers may experience a paywall.)

More than 97% of the world's particle accelerators are used for commercial purposes

Only a few hundred of the over 30,000 particle accelerators worldwide are used for research. Most are involved in medical imaging and treatment, food sterilization, semiconductor processing, cargo screening, and radioisotope production. They're also used to modify the properties of polymers.

A snapshot of progress in cancer treatments

The American Association for Cancer Research's "Snapshot of a Year of Progress" offers an overview of significant advancements in cancer research and treatment over the past year. Take a quick look at the rapid pace of scientific discovery and the translation of research findings into clinical practice. In 2024 alone, health regulators approved 15 new anticancer therapies alone.

Pigs are of particular interest for xenotransplantation because they are close to human size, are easily raised in captivity, and have large litters.

View a breakdown of the identified species on Earth, led by about one million insect species, while mammals such as humans make up one of the smallest groups.

Scientists using gene therapy recently managed to regenerate retinal cells in the lab—a breakthrough for mammals that could potentially lead to future treatments for human retinal diseases.

Biologists believe over 5,000 coyotes inhabit LA as of 2025

Panic and fear of coyotes spread in the 1980s after the first recorded instance of a human killed by the animal in American history, but LA and Chicago residents today are learning to live alongside the animal. Research shows that coyotes can even benefit urban ecosystems by helping to control populations of geese and deer, and by improving songbird survival through preying on cats.

Up to 225 cases of leprosy in the US are diagnosed each year

Most cases in the US are imported, meaning someone was infected in a country where it was more common. Since symptoms can sometimes take decades to appear, tracing the origin of the disease can be hard.

Animal-to-human pathogens constitute 75% of emerging infectious diseases

Zoonotic diseases encompass more than 200 diseases transmitted from animals to humans, wherein humans are usually accidental hosts. Ranging from rabies to HIV to monkeypox, this overview lists some of the most common viral threats.

There was a backlog of at least 25,000 untested rape kits in 2022, according to data submitted from 30 states and Washington, DC.

Autism research has faced significant cuts under Trump

One of the largest areas of halted research was at the Department of Education where its Institute of Education Sciences had studies underway focused on developing and evaluating school-based interventions for students with autism. DOE was significantly cut back as part of federal government layoffs.

Nearly 90% of the world's 12,187 nuclear warheads are held by Russia and the United States.

Psychedelics are being fast-tracked for research after a 2026 executive order

Many such compounds (including LSD, psilocybin, and more) are classified as Schedule I drugs—illegal to possess and federally regarded as having no medical use. Researchers say such restrictions have created significant hurdles for formal clinical trials. With this executive order, the FDA will enable work particularly focused on depression, PTSD, and alcohol use disorder.

See how global nuclear arsenals surged—then shrank—by country since 1945

Worldwide nuclear stockpiles peaked at over 60,000 warheads in the mid‑1980s during the US-Soviet arms race. Today, about nine nations collectively maintain roughly 12,000 warheads, with Russia and the US still holding the majority.