Rabies is close to the deadliest infection there is. Once symptoms start, it kills almost everyone who gets it. It is also one of the easiest deadly diseases to stop. Wash the wound and get the shots soon after a bite, and protection is nearly complete. Both things are true for the same reason. The virus takes a slow, hidden road to the brain, and the vaccine works only if it gets there first. Here is how that race works, why bats matter so much in the United States, and how whole countries are now getting rid of rabies from dogs.
A virus that travels along your nerves
Rabies is caused by a virus in a group called lyssaviruses. The name comes from Lyssa, the Greek word for madness. Under a microscope the virus looks like a tiny bullet, about 180 nanometers long. A nanometer is a millionth of a millimeter, so you could line up more than 5,000 of them across the head of a pin.
It lives in the saliva of an infected animal. It usually gets into a person through a bite or a scratch, and sometimes through saliva that lands in the eyes, mouth, or an open wound. Rabies can infect any mammal, including dogs, cats, cattle, and wild animals.
What makes it unusual is where it goes next. The virus does not race through the blood. It first multiplies quietly in the muscle near the wound. Then it slips into the end of a nerve and travels backward along the nerve fiber toward the spinal cord and brain, riding the cell’s own transport system. While it is inside the nerves, the immune system barely notices it, and no test can find it.
That trip takes time. According to the World Health Organization (WHO), the gap between infection and the first symptoms, called the incubation period, is usually two to three months. It can be as short as a week or as long as a year, depending on where the virus got in and how much of it there was.
Why symptoms mean it is too late
Once the virus reaches the brain, it causes inflammation of the brain and spinal cord, which doctors call encephalitis. The first signs are vague. WHO lists fever, pain, and odd tingling, pricking, or burning around the old wound. From there the illness moves fast.
There are two forms. About 80 percent of people get furious rabies. They become agitated and confused, see things that are not there, and develop the symptom that gave the disease its old name, hydrophobia, or fear of water. Swallowing sets off painful spasms in the throat, so even the sight of a drink can cause panic. Some people also react badly to a puff of air on the face. Death usually follows within days, when the heart and breathing fail.
The other 20 percent or so get paralytic rabies. Muscles slowly go weak, starting near the bite, and the person drifts into a coma. It is quieter and often lasts longer, and it is easy to mistake for other nerve diseases, which is one reason rabies is undercounted.
By this stage the virus has spread outward from the brain to the salivary glands. That is how an infected animal passes it on, and it is why rabid animals drool and bite.
Once symptoms appear, rabies is fatal in virtually every case. Only a handful of people have ever survived it. The best known is Jeanna Giese, a 15-year-old from Wisconsin. In September 2004 a bat flew into her church, and she picked it up to carry it outside. It bit her finger. She did not get the shots, and a month later she fell ill. Doctors at Children’s Wisconsin put her into an induced coma, hoping to protect her brain while her body made antibodies. She woke up, recovered after months of rehabilitation, and became the first known person to survive rabies without the vaccine.
Her treatment became known as the Milwaukee protocol, and doctors tried it on many patients after her. It almost always failed, and by 2015 specialists had concluded that it does not work. Some experts suspect Giese simply caught a weaker strain. Either way, her case is the rare exception, not a cure.
The shot that beats the clock
Before 1885, a bite from a rabid animal was close to a death sentence. That July, a 9-year-old boy named Joseph Meister was badly bitten by a dog thought to be rabid. He was taken to Paris to see Louis Pasteur, a chemist who had been working on rabies with Émile Roux. Their vaccine had protected dogs, but it had never been tried on a person.
On July 6, 1885, Meister got his first injection. It was made from the spinal cord of a rabbit that had died of rabies, dried for days to weaken the virus. Twelve more doses followed over the next 10 days, each a little stronger. The boy never got sick. Pasteur, who was not a licensed doctor, had taken a real risk. The success made him famous, and the Pasteur Institute opened in Paris in 1888. Meister later worked there as a caretaker for the rest of his life.
The idea still works today, and the reason is that slow trip along the nerves. A vaccine given after a bite teaches the body to make its own antibodies, which takes a week or two. Because the virus usually needs much longer than that to reach the brain, the body wins the race. For serious bites, doctors also inject ready-made antibodies, called rabies immune globulin, into and around the wound. Those hold the virus back while the vaccine kicks in.
WHO calls this post-exposure prophylaxis, or PEP. It has three parts: wash the wound well with soap and water for at least 15 minutes, start a course of rabies vaccine, and add the immune globulin when the exposure is serious. In the United States, the Centers for Disease Control and Prevention (CDC) describes PEP as wound care, immune globulin, and four or five vaccine doses, and says it is nearly 100 percent effective when it is given promptly. Modern vaccines go in the arm, and their side effects are about like a flu shot. The old belly injections people still joke about came from nerve-tissue vaccines that most countries stopped using decades ago.
WHO sorts exposures into three levels. An animal licking unbroken skin is not an exposure, and washing is enough. A nibble or a small scratch that does not bleed calls for the vaccine. A bite or scratch that breaks the skin, saliva on broken skin or in the eyes or mouth, or direct contact with a bat calls for the vaccine plus immune globulin. More than 29 million people a year get rabies vaccine after a possible exposure, according to WHO, including around 100,000 Americans, by the CDC’s count.
If you are bitten or scratched by an animal that might have rabies, wash the wound and call a doctor or your local health department the same day. They can tell you whether you need the shots.
Why bats matter so much in the United States
Rabies has become rare in people in the United States. In the early 1900s it killed 100 or more Americans a year. Today the CDC reports fewer than 10 deaths a year, and usually just one or two. The big change was vaccinating pet dogs and cats, which wiped out the strain of rabies that spreads among dogs here.
The virus never left the wild, though. More than 90 percent of animal rabies cases reported in the United States are in wildlife, mostly bats, raccoons, skunks, and foxes. The CDC says nearly 3 out of 4 Americans live in a community where animals carry rabies, and it is found in every state except Hawaii.
Bats are now the main danger. At least 7 out of 10 people who die of rabies in the United States were infected by a bat. A bat bite can be so small that a person does not notice it or does not think it matters, so they never get the shots. That is why health officials say any direct contact with a bat is worth a call to a doctor.
Some animals are almost never the problem. Squirrels, rats, mice, chipmunks, rabbits, and hamsters very rarely carry rabies and are not known to pass it to people, probably because an attack by a rabid animal usually kills them. That makes rabies quite different from plague, which lives in wild rodents and the fleas that feed on them.
Travel is the other risk. The CDC counts more than 80 people in the United States who have died since 1990 after catching rabies abroad, often from a dog bite in a place where dog rabies is still common.
A vaccine hidden in a snack
You cannot catch every fox and raccoon to give it a shot, so wildlife agencies feed them the vaccine instead. Switzerland largely cleared rabies from its foxes by leaving chicken heads laced with vaccine in the Alps. Today the baits are small packets wrapped in a coating animals like to eat. One brand used in North America, called ONRAB, is coated with a sweet mix of fats, wax, sugar, and artificial marshmallow flavor.
In the United States, wildlife workers put out more than 5 million of these baits every year, according to the CDC. Veterinarians vaccinate more than 90 million pet cats and dogs a year on top of that.
The push to end rabies from dogs
Worldwide, the picture is very different. Dogs cause up to 99 percent of human rabies cases. WHO’s latest model estimates about 44,000 deaths a year, and other estimates run as high as 59,000 to 70,000. Everyone agrees the real number is uncertain because so many cases are never reported. Most deaths happen in Asia and Africa, and about 40 percent are children under 15.
Cost is a big part of the problem. WHO put the average price of a course of PEP at about $108 in 2018, before travel and lost work, in places where many people earn $1 to $2 a day. Vaccines and immune globulin are often out of reach or unaffordable for the people who need them most.
The cheapest fix is the one in the photo at the top of this page. WHO says vaccinating dogs is the most cost-effective way to protect people, because it stops the virus at its source. Killing stray dogs does not work. WHO and its partners have set a goal called Zero by 30 to end human deaths from dog-spread rabies by 2030.
Progress is slow but real. As of September 2026, WHO has validated three countries for ending dog-spread human rabies as a public health problem: Mexico, Bhutan, and Chile. Bhutan was confirmed on September 4, 2026, the first in WHO’s South-East Asia region, after going without a human death from dog rabies since June 2023. Chile followed on September 14, the first in South America. Across the Americas, human cases of dog-spread rabies have fallen by more than 98 percent since 1983, according to WHO.
The bottom line
Rabies is almost always fatal once symptoms show and almost always preventable before then. The gap between those two facts is the slow trip the virus makes along the nerves, which gives a vaccine time to win. That is why a bite from a dog, bat, raccoon, or other animal that might carry rabies is worth a same-day call to a doctor, even if it looks minor. World Rabies Day falls on September 28, the date Pasteur died in 1895.
Further reading
Rabid: A Cultural History of the World’s Most Diabolical Virus — Bill Wasik and Monica Murphy trace rabies from ancient myths and werewolf legends to Pasteur’s gamble and the modern fight to contain it.
Spillover: Animal Infections and the Next Human Pandemic — David Quammen’s gripping account of the diseases that jump from animals to people, and the scientists who chase them.