By Toni Perling
Something you might not know about bats: Bananas wouldn’t exist without them. Or avocados or mangoes, for that matter. But despite being key contributors to the ecosystem by pollinating fruit plants and feeding on crop-destroying insects, the species is probably most (in)famous for being one of the main carriers of the deadly disease known as rabies.
Passed to humans through contact with a bat or other infected animal, the virus attacks the central nervous system, potentially causing brain disease and death. According to the Centers for Disease Control and Prevention (CDC), an estimated 70 percent of cases in the United States, including five fatalities in 2021, were caused by exposure to rabid bats.
Thankfully, there are shots you can take after exposure to a bat that are highly effective at preventing the disease. These vaccines, known as post-exposure prophylaxis (PEP), are not nearly as taxing as they once were. Until the 1980s, people who were exposed to rabies had to receive a dozen or more injections delivered into the stomach with a long needle. Today’s treatment regimen is four standard-sized vaccinations administered in the arm, plus a shot of immunoglobulin, a medication which delivers antibodies to your immune system to specifically target and neutralize rabies virus.
At least two of our CDC Foundation colleagues have recently had occasion to take those shots. In January of this year, Foundation President and CEO Judy Monroe was surprised by a bat who visited her at home.
“While reading in my living room with a throw slung over my shoulders, I felt something on my right hand and flung the throw away,” said Monroe. “To my surprise, a bat was in the throw! I was not certain the bat had bitten me, but I took no chances and contacted authorities immediately and started PEP.”
Dusty Staake, a CDC Foundation laboratory scientist working with the Illinois Department of Public Health (IDPH) Division of Labs in Springfield, took a preventive series of pre-exposure vaccines when she was assigned to the rabies lab after the state saw a concerning rise in virus-carrying bats.
“Our busy months for bats are in the summer,” Staake explained. The flying mammals can enter a house through a chimney, attic or open window, looking for insects to dine on, as well as protection from predators. “You know they hide, and they migrate come wintertime,” she said.
Staake, who holds a microbiology and biochemistry master’s degree with a specialization in public health lab science, recently tested 28 bats from across the state that came up positive for rabies. To properly perform the necessary lab tests on a deceased animal suspected of having the disease, Staake must extract its brain tissue. That may not be easy—in the heat of the moment, homeowners sometimes kill the bat by crushing its skull. “Then there’s nothing we can do on our end,” she said.
“If you have a bat in your house, definitely reach out to both animal control and your local health department to find out the steps that you can take for proper collection techniques,” she advised. Testing is necessary to avoid what could be a costly vaccine regimen.
Once the tissue samples are collected, there’s no doubt about the result. Staake reads the slide under a fluorescent microscope in a dark lab. “When you’re looking at a positive, you’ll see what’s called a candy apple green fluorescence,” she said. “There is no question the virus is there.”
There are other CDC Foundation staff working on rabies at the department as well. Chanée Massiah, a senior epidemiologist, is assigned to the IDPH and leads a group that cross-references and inputs rabies vaccine data and reports from medical providers, so that the IDPH can make sure people who are potentially exposed to rabies are getting their shots at the right time and in the right order.
Massiah, whose team includes fellow CDC Foundation staff members Micah Barrel, Kalie Ganem and Malika Fontes, is rightly proud of the work they’re doing. “Not all providers are well versed with rabies vaccines. So we’re hoping to spread awareness about the proper sequence of the shots and valid exposures that require them.”
And it’s key to start the vaccine regimen before symptoms show up. Animals and humans infected with rabies really do foam at the mouth. That’s because the virus produces a lot of saliva, while at the same time causing the swallowing reflex to go haywire. These paralyzing and painful spasms in the mouth and throat also produce hydrophobia—fear of drinking water. Rabies patients can also suffer burning sensations at the wound site, sensitivity to light, hallucinations and aggression.
At the time of her encounter, Dr. Monroe wrote, “Human rabies is 99 percent fatal. However, it is 100 percent preventable through vaccinating pets against rabies, avoiding contact with wildlife and unknown animals and seeking medical care as soon as possible after being bitten or scratched by an animal. Rabies is a horrible disease and represents just one disease that can be prevented by a strong public health system, education, communication and vaccines.”
Toni Perling is a senior communications officer for the CDC Foundation.