Do you need a preventative rabies vaccine? Probably not.

Of all the deadly diseases that can spread from mammals to humans, rabies is the most infamous. Cujo had it. Old Yeller had it. A squirrel in “National Lampoon’s Christmas Vacation” had it. Unfortunately, this virus doesn’t only live in fiction. It kills at least 59,000 people a year and is present in over 150 countries. On that list is the U.S., which is seeing a nationwide surge in reported cases of human exposures to rabid or possibly rabid animals. If left untreated, rabies is always fatal (both for animals and humans). On the bright side, it’s also 100 percent preventable. Typically, in the U.S., humans get vaccinated for rabies after suspected rabies exposure, but right now many of us are wondering: Can and should you get vaccinated against rabies just as a precaution? Is there any benefit in getting a preventative rabies vaccine? The simple answer is no. Getting a pre-exposure vaccine doesn’t protect you from contracting the disease, and if you have an encounter with an animal that might have rabies, you’ll still need to get follow up doses regardless. Debunking myths about the rabies vaccine Before diving in, let’s clear up some common misconceptions about rabies and the rabies vaccine. Rabies is a zoonotic virus that comes in two types: furious rabies and paralytic rabies. Both types of rabies attack the central nervous system and both are fatal. Any mammal can be infected with rabies, and if infected, can transmit it to other animals or humans through a bite or scratch—even if you can’t see or feel the wound. Though rabies doesn’t turn its victims into people-eating zombies, as Hollywood would have us believe, it does deliver an acutely agonizing death. The modern vaccine for rabies is made from cell culture. A cell culture vaccine contains no live virus. It is literally impossible for you to get rabies from the vaccine, which, you may be surprised to hear, is also pretty painless. Is the rabies vaccine painful? “The rabies vaccine is no more painful than a flu shot,” Dr. Edward R. Rensimer, a board-certified doctor of infectious diseases and internal medicine and director of the International Medicine Center in Houston, tells Popular Science. If exposed to a rabid or possibly rabid animal, you will require more than one dose of a rabies vaccine. “The injection site and number of doses recommended are dependent on the type of exposure you’ve had to a potentially rabid animal,” says Dr. Mirava Yuson, an epidemiologist and postdoctoral researcher working at the UCLA TIDE (Translational Infectious Disease Eco-epidemiology) Lab. “You can expect, for example, that a bite wound induced by an animal that’s suspected to be rabid, versus a light scratch from an animal that is not suspected to have rabies, will merit different doses and numbers of recommended boosters that are needed to complete a vaccine series.” The rabies vaccine is typically administered after an exposure has occurred. Image: Whispyhistory / CC BY-SA 4.0 The rabies vaccine is very safe Both Yuson and Rensimer cannot overstate the safety and efficacy of the rabies vaccine and emphasize that side effects, should they occur, are minimal. “It is analogous to the flu vaccine,” Rensimer says, adding that in his more than 45 years of administering the vaccine he’s never seen a major adverse event. “A very small minority of people in the 24 hours after the first dose may have low-grade fever, body aches, and malaise.” Should you get the rabies vaccine to prevent getting the disease? So, the rabies vaccine is a totally safe, 100 percent effective, and generally gentle vaccine? Sign us up! In all seriousness, why wouldn’t we get this vaccine, regardless of exposure risk, especially now, when rabies outbreaks and mass rabies exposure events are on the rise across the U.S.? Turns out there are a couple reasons why getting the rabies vaccine without any known risk exposure doesn’t make sense. First, the “better safe than sorry” approach doesn’t work with rabies. Getting a rabies shot before a risk exposure event does not prevent you from becoming infected with rabies, nor does it minimize the effects of the fatal virus should you get it. You will still die if untreated by vaccinations post-exposure. “There is a pre-exposure rabies vaccine that people get before traveling to rabies-endemic areas; however, the problem is, even if you get it, the minute you are exposed to a potentially rabid animal, you need a second dose, the post-exposure vaccine,” Yuson says. “Veterinary professionals like me get them every year, but that does not preclude us from needing a post-exposure dose should we be potentially exposed. One vaccine is never enough and that is supremely important to know.” Related 'Ask Us Anything' Stories Second, getting a rabies vaccine regardless of risk exposure could confuse your case for clinicians if you do eventually face potential risk exposure. “Getting the vaccine without known risk exposure can unfortunately cause some issues with the next dose should you be exposed or possibly exposed to a rabid animal,” Yuson says. “It becomes a question [for doctors]: ‘Do we start the regimen all over?’” How to not get rabies The best way to stay safe is also a bit of a bummer: It’s to limit contact with wildlife. All mammals are capable of getting infected with and transmitting rabies. In the U.S., there are infected raccoons, foxes, skunks and, most of all, bats, which are responsible for 70 percent of rabies deaths in people. “The thing with bats, without getting too technical, is that they’re the only flying mammals,” Yuson says. “They can transmit diseases over great distances and can carry multiple diseases without themselves being sick, and they have very small fangs. You may not even feel the bite or often won’t see a bite wound.” Because you may not even know you were bitten, it’s imperative that, after any encounter with a bat or any other potentially rabid creature, you immediately go to the ER and get the first of what will likely be a few post-exposure vaccines. Bats are responsible for 70 percent of rabies deaths in people. Image: Getty Images / Bence / 500px The vaccine is literally the only way to survive if you’ve been infected. There is no “wait and see” window, either. “Once symptoms manifest, there is no cure for rabies; it has a 100 percent mortality rate and the only way to prevent infection after exposure is through vaccination,” Yuson says. It’s a scary time, and rabies is a very scary virus, but remember that even with the spike in reported cases of human exposures to rabid or possibly rabid animals, a human dying from rabies is, in the U.S. at least, an incredibly rare thing. “We average one to six cases of rabies a year in the U.S.,” Rensimer says. Unfortunately, because of rising temperatures (rabies loves warm weather) and continued encroachment on wildlife habitats by good old mankind (leads to increased exposure risk among humans and pets), rabies doesn’t look to be going anywhere anytime soon. But thanks to science, there’s no real reason to worry, because if for any reason we do come into contact with a possibly rabid animal, there’s a safe, accessible, and 100 percent effective vaccine available. In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us. 2026 Popular Science Home of the Future Awards 39 products that will improve your everyday life.