There's no cure for West Nile virus—and infection can leave patients with permanent symptoms

Most cases of West Nile virus are asymptomatic in people

About 1 in 5 infected people develop symptoms from West Nile, including symptoms such as fatigue, head and body aches, and vomiting. But around 1% of patients develop severe complications such as encephalitis or meningitis, which can be life-threatening. Those who are most likely to become severely ill are people over age 60.

Long-term memory issues among West Nile survivors may be from immune response, not virus

Rodent research suggests that long-term neurological complications such as fatigue, weakness, difficulty walking, and memory loss, may be due to the immune system systematically destroying parts of neurons in the brain in response to the infection, rather than due to viral infection itself.

US West Nile case numbers were up 40% in 2025, nationally

This surprising surge may be due to warmer temperatures and elevated rainfall—leading to the ideal conditions for mosquitoes to thrive and breed in standing water. Symptoms can be hard to recognize when the disease is mild—similar to a flu. But neurological complications can lead to hospitalization and be deadly.

Protecting yourself from West Nile involves avoiding getting bites and clearing standing water

The best prevention against West Nile is avoiding getting bit. That means covering your arms and legs with long, loose-fitting clothes, wearing insect repellant—on top of, not under sunscreen, and making your environment as inhospitable to mosquitoes as possible, including clearing any standing water.

West Nile Virus is maintained in nature, even without human infections

Mosquitoes pick up the virus when they feed on birds, and then pass it to other birds with their bite, delivering it via virus-laden saliva. Hundreds of different North American bird species can harbor the virus—even if they don't all get sick from it.

West Nile is named after the district in Uganda where it was first isolated from a patient

In 1937, scientists isolated the virus from a woman in the West Nile District of Uganda. It's since been detected in much of Africa, Eastern Europe, West Asia, the Middle East, and was first detected in US patients during an outbreak in 1999.

Horses have four licensed West Nile vaccines—but humans have none

A major hurdle for West Nile vaccine development is the lack of a market for it since so many people are symptomatic for the infections. Still, a growing number of infections, including a 40% spike in 2025, may change that calculation.

Scientists found that if cats in the lab ate infected rodents they could get West Nile

But beyond the lab setting there have been no known cases of cats or dogs contracting the virus this way. Instead, those animals have been sickened when an infected mosquito bit them—just as with human infection.

Nearly 5,500 crows died during four months in 1999 from West Nile in NYC

Subsequent testing made clear the disease at that point was 100% fatal to crows. From 1999 to 2004, millions of birds died as West Nile spread across North America, but the virus fortunately became less virulent as it moved westward.

There's a West Nile virus prevention rap—and it's amazing

This catchy rap from biologist MC Bugg-Z and the Fairfax County government in Virginia walks people through prevention steps and the dangers of the virus, telling listeners to "rock" insect repellant and talking about the history of the disease in the US.

Hear from a NYC public health official who led the first US investigation into West Nile

This podcast walks through the investigation into the first US outbreak of West Nile, and how the virus had never been seen in the Western Hemisphere. The official discusses how she thinks the origin of West Nile in the US may have been birds or other animals that were brought here illegally.

Untreated malaria can lead to blocked blood vessels in the brain, coma, and organ failure

Malaria is treatable with medications, but sometimes even after treatment, infection can come back because the disease-causing parasite wasn't completely eliminated. Patients may also have symptoms that emerge years after the initial infection and treatment.

Zika virus shocked scientists because the mosquito-borne disease causes birth defects

This revelation, confirmed in 2016, marked the first time that a mosquito-borne disease was known to cause birth defects. Fetuses exposed to the Zika virus during pregnancy sometimes suffer from neurological complications and microcephaly, a small-headed condition associated with neurological development issues and impairment.

More than 20 mosquito-borne and tick-borne diseases are found in the US

Children, older adults, and people with compromised immune systems are at particular risk of poorer health outcomes from these diseases. But dog owners and outdoor enthusiasts are among those at particular risk of contracting these illnesses, which include Lyme disease, Zika, and the condition Alpha-gal Syndrome.

Malaria case in Maryland stumped doctors in 2023—leading to the wrong treatment

When the state had its first locally acquired malaria case in over 40 years, the patient was misdiagnosed with a more common tick-borne infection, leading to weeks-long treatment for the wrong infection. The patient had symptoms that could occur with malaria or with babesiosis, a disease caused by Babesia parasites and transmitted by ticks in the US.

Cryptococcus neoformans, a growing threat, causes infections in the brain and lungs

This inhalable, microscopic pathogen is found worldwide. It rarely causes illness, but it can take root in those with compromised immune systems, including people with advanced HIV/AIDS. Symptoms of cryptococcal infection—such as a stiff neck, vomiting, and confusion—can begin weeks or months after breathing in spores, though sometimes symptoms won’t appear for years. There are no known cases of transmission between people or between people and animals.

Dengue is sometimes called 'breakbone fever' because it's so painful

Though this mosquito-transmitted disease can be asymptomatic, in more severe cases patients experience high fever, muscle spasms, and joint pain. The experience can be so excruciating that it feels like the patient's bones are broken, thus the nickname of breakbone fever. It's the world's fastest spreading tropical disease.

Marburg virus, related to Ebola, is also extremely deadly, and has no available vaccine.

There's no cure for Ménière's disease, only medications to reduce frequency of attacks

Ménière's disease is an inner ear problem that can cause vertigo and hearing loss. Most of the time, Ménière's disease affects only one ear.

Marburg virus, related to Ebola, is also extremely deadly

Discovered nine years before Ebola, Marburg is part of the same filovirus family. While this virus is less contagious, it can still be deadly. Currently, no vaccines exist against this disease. (Some users may encounter a paywall.)

The rare but deadly time bomb lurking after a measles infection

Subacute sclerosing panencephalitis, also known as Dawson disease, is a progressive and fatal neurodegenerative condition caused by a dormant measles infection. Typically, patients recover from measles normally, with the symptoms of SSPE only appearing years or even decades later. The incidence rate in unvaccinated pediatric patients is estimated to be around one in 1,300.

There are more than 200,000 cases of HFMD annually, and there's no cure

The highly contagious disease is caused by several viruses and it primarily affects little kids. It causes red spots in and around the mouth, hands, feet, and even the buttocks. They often become painful water-filled blisters that can burst and cause small ulcers. Eating and drinking is uncomfortable for about a week so patients need to be careful not to become dehydrated.

Food poisoning can sometimes cause serious long-term health issues

Although foodborne illness can be relatively mild and cause short-term discomfort, more rarely it can also cause long-term severe health consequences, depending on your individual risk factors, the severity of your sickness, and the care you receive. Kidney failure is one serious complication associated with certain types of food poisoning. Meningitis, hepatitis, arthritis, and pancreatitis are also rare and serious foodborne illness complications. If a pregnant person gets food poisoning, it can cause health issues for the fetus.

Being struck by lightning has a mortality rate of about 10%

Near-immediate deaths are the result of electrical disruptions in the heart and nervous system, causing cardiac arrest, but severe skin burns, temporary paralysis, and blown eardrums are more common. About 74% of survivors are left with a long-term disability, which includes brain damage and changes in memory and mood.

Blood tests for Lyme disease tend to come up as false negatives in the week after a bite

It can take several weeks for Lyme antibodies to develop, which is what blood tests would be detecting. That's why many clinicians will prescribe antibiotic treatment immediately after a bite if the individual develops the characteristic bullseye rash of Lyme or gets bitten in an area of the country known to have high rates of Lyme.

Losing a brain-computer interface can trigger lasting psychological distress

A clinical trial participant with severe epilepsy described becoming “one” with her implant after it gave her unprecedented control over her seizures. When the device was removed due to the company shutting down, she experienced deep emotional trauma and a sense of personal loss.

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

Ebola infects and disables immune cells, triggering a cascade of events that leads to small blood clots throughout the body, weakening blood vessels and interrupting blood flow to key organs.

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.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

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

Firework or sparkler burns, even if they cover a relatively small area of skin, can significantly affect our range of motion.

Apeirophobia is an overwhelming fear of living forever, perhaps stemming from the brain's inability to conceptualize an infinite life.

After 25 people used virtual reality headsets to practice flying with virtual wings—flapping their arms—their visual cortex responded to the wings almost as if they were real arms, treating them as body parts.

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

See these 16 pieces of art evoking phobias of snakes, flying, spiders, and more. 

Poison ivy's characteristic rash is caused by an allergic response to an oily compound in the plant called urushiol.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

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

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

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.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

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.

NBA superstar Victor Wembanyama spent the 2025 summer training with monks in central China to enhance his body and mind.

Planarian flatworms are small, aquatic worms with exceptional regenerative capabilities. When cut, the worms can regenerate multiple bodies in a matter of weeks.

After her fellow cult members tried to kill her with an LSD-infused hamburger, one member of the Manson Family, the murderous cult led by Charles Manson, decided to testify against the group's leader.

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

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.

A Yale student wrote a profound essay about the consulting industry's influence on elite college students that was published in a book of her writing after she died in a post-graduation car accident.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.