Say you wake up with a bat in your bedroom.
It’s not uncommon in Minnesota this time of year. There’s a lot of movement of bats in August as young bats are starting to leave their colonies in caves and crevices, and lots of bats are getting ready overwinter — often in attics or outbuildings.
So back to your night visitor: Do you grab a box and try to capture it? Hide under the covers and scream? Get a hotel?
Whatever your chosen course of action, health officials in Minnesota want to make sure you add another concern: that you might have been exposed to rabies.
Rabies looms large
Rabies is a disease caused by viruses in the Lyssavirus family. People have been aware of it for thousands of years: Discussions of the disease are found in ancient texts and it’s depicted in medieval paintings.
It’s generally transmitted by coming into contact with the saliva of an infected animal through a bite, and it works like this: The virus travels from the site of the bite up the nerves to the brain, where it causes swelling.
The virus then travels to the salivary glands, filling saliva with the virus, said Joni Scheftel, state public health veterinarian and supervisor of the Minnesota Department of Health’s Zoonotic Diseases unit.
While some animals with rabies may be lethargic and seem tame, other cases take on a more violent form. Symptoms of rabies may include excessive salivation, confusion, fear of water, hallucination and hyperactivity, among others.
Because of these highly visible symptoms — and the fact that rabies is almost always fatal by the time it actually develops — the disease looms large in people’s imagination.
Rabies may have inspired folklore about vampires, the bat-like mythical undead, according to researchers. Vampires’ purported dislike of light and garlic could have come from hypersensitivity associated with rabies. And of course, vampires bite to drink blood. In more recent years, the disease has been portrayed in film in movies like “Old Yeller” and “Cujo,” adapted from a Stephen King novel. Atticus Finch shoots a rabid dog in “To Kill a Mockingbird.”
But in spite of all the fear it inspires, rabies is not common in Minnesota.
Few cases in Minnesota
Last year, Minnesota had 32 confirmed positive cases of rabies, all in animals, according to MDH data — about 1.5 percent of the 2,145 animals tested. The positive cases included 27 bats, three skunks, one dog and one cat.
When an animal is captured and tested for rabies, its brain is cut in half and its stem is searched for fluorescent antibodies, which indicate rabies, said Jody Lulich, a professor in the University of Minnesota’s Department of Veterinary Clinical Sciences.
While bats make up a large percentage of the animals tested, just 3 percent to 4 percent of bats tested for rabies in Minnesota test positive, Scheftel said. Since those bats are ones that have come into contact with humans, it’s not a random sample. It’s thought that 1 percent of bats overall are rabid.
In Minnesota, skunks most commonly test positive: About 45 percent of these animals tested for rabies between 2003 and 2018 in Minnesota were rabid. About 6 percent of cattle that underwent testing were positive.
Rabies test results by animal type in Minnesota, 2003-2018
Source: Minnesota Department of Health
The number of rabies cases in cats and dogs has gone down since pet vaccinations became common.
Which animals are at most at-risk of rabies varies by region, Scheftel said. Raccoons aren’t susceptible to the variant of the virus that skunks carry in Minnesota. As a result, there are very few rabid raccoons in Minnesota: While the state tests about 75 per year, there have only been three positive cases in the last quarter-century.
“There is a variant that’s associated with raccoons that’s found on the East Coast, so the situation there is very different,” Scheftel said. Because rabies is so regional, it’s important to contact health officials near where you might have been exposed to the virus.
Globally, there are as many as 60,000 deaths per year resulting from rabies. But in the U.S., where there’s typically rapid response to potential rabies cases, there are only between 1 and 3 reported cases of rabies in humans per year. The last time a human died from rabies in Minnesota was in 2007, when a man at his cabin handled a bat with his bare hands and was unaware that it bit him and that he was at risk of rabies.
What to do
If Minnesotans suspect they’ve been exposed to rabies, they’re advised to call the state’s rabies hotline at 651-201-5414.
Staff are available to the public from 8 a.m. to 4:30 p.m., and callers can get help assessing whether anyone potentially exposed to rabies needs treatment, based on the situation. Doctors and vets can get information at that number from the Minnesota Department of Health 24/7.
If public health workers believe there’s a possibility an animal is rabid, they’re likely to ask that the animal be submitted for testing.
Results come back quickly. Most of the time, they’re negative, but when they’re not, the Minnesota Department of Health gets on the case quickly.
“Every single laboratory-confirmed positive case, we call immediately to make sure everyone exposed to that rabid animal seeks medical care and is prevented from coming down with rabies,” Scheftel said.
Treatment means getting a rabies vaccine. The vaccine was first developed in 1885. Today, it includes four shots in the arm within 14 days. That’s a big improvement over how anti-rabies vaccines were administered up until the ’80s — via 21 shots with a long needle in the stomach.
When it’s not possible to test an animal for rabies, a person who was potentially exposed to the disease may be given shots to prevent it.
Of concern in public health is how much the cost of the vaccine has been rising in recent years: Rabies shots costs significantly more in the U.S. than they do in other countries, and patients without medical insurance can be stuck with bills in the thousands of dollars.
Of course, people who are bitten by an animal that’s potentially infected with rabies don’t have much of a choice.
Because bats are the rabies carriers people most often come into contact with, the Minnesota Department of Health’s rabies page has a video on how to capture a bat and a flowchart on what to do if you come into contact with one.
As long as people take precautions in Minnesota, they shouldn’t be too worried. The disease is preventable in humans.
“There’s a very large public health infrastructure set up to keep people safe (to prevent) human rabies deaths here in Minnesota,” Scheftel said.