Stringer/Getty Images
Stringer/Getty Images

15 Useful Facts About Lyme Disease

Stringer/Getty Images
Stringer/Getty Images

As summer nears and you spend more time outdoors in one of the many beautiful natural spots in the United States, be sure to dress for the season—tick season, that is. Some experts say 2017 may be an especially tick-infested year. Deer ticks (Ixodes scapularis) carry a bacteria that causes Lyme disease, an infection from a bacterium that coils waiting in their insect bodies. Lyme-carrying deer ticks are especially prevalent in the upper East Coast, the upper Midwest, northern California, and the Oregon coast. While not every tick carries the bacteria that lead to infection—and some carry other pathogens—it’s best to take precautions to prevent bites, and seek medical attention if you have been bitten. The infection can cause long-lasting damage if not treated early. Here are 15 facts you need to know about Lyme disease.

1. LYME DISEASE IS CAUSED BY COILED BACTERIA.

Lyme disease is caused by the bacterium Borrelia burgdorferi, a spirochete, or tightly coiled bacterium that looks like a tiny spring under a microscope. Spirochetes are very simple, slow-replicating bacteria that require a mammalian or avian host to survive. According to Timothy Sellati, chair of the infectious diseases department at Southern Research, a nonprofit research institution in Birmingham, Alabama, “It takes on the order of 18–20 hours for a single spirochete to divide into two.” That’s incredibly slow, compared to other bacteria like E. coli, which can replicate every 20 minutes. Because Borrelia replicates so slowly, and they don’t reach high numbers, “They do not show up easily in a blood test,” Sellati says.

2. TICKS PREFER A LONG MEAL.

Sellati explains that ticks are very different feeders from mosquitoes, which he calls “hit-and-run feeders.” Ticks will feed over a period of three to five days before they become fully engorged. Female ticks generally only take three “blood meals,” he says, in the duration of their lifespan. They take one blood meal after hatching from their egg into the larval stage, another after they molt into their nymphal stage—the stage where they are most likely to bite you—and a final “big meal” in preparation for laying thousands of eggs. Adult male ticks generally don’t feed, he says.

3. THEY ARE A VIRULENT DISEASE VECTOR …

When an infected tick bites a human, the waiting spirochetes—which live essentially dormant in the tick’s gut until environmental cues such as changes in temperature and oxygen availability awaken them—travel from the tick’s gut to its saliva glands. “From the saliva glands they can literally be spat into the bloodstream that the tick is feeding on,” Sellati says. Once they enter the bloodstream, spirochetes travel to various body tissues, because if they stay too long in the bloodstream, they’ll get killed by their host's immune system. “Once it gets away from site of inoculation, it shows a bias toward joints, heart, central nervous system,” Sellati says.

4. … WHICH LEADS TO INFLAMMATION.

“The bacteria has components that are very effective at eliciting an inflammatory response,” Sellati explains. While Borrelia don’t produce toxins like other bacteria, they do incite inflammation in sensitive parts of the body such as the joints, heart, and brain. “That inflammatory response is important to help kill and clear the spirochetes, but it causes collateral damage as well.”

5. INFECTIONS MAY BEGIN WITH A BULL'S-EYE.

The first symptom to look for in about 80 to 90 percent of Lyme cases is a telltale rash of an infected tick bite, called an erythema migrans (EM) rash, which looks a lot like a red bull's-eye, and usually appears at the site of a tick bite within seven to 14 days, according to the American Lyme Disease Foundation. However, the rash does not appear in every instance of Lyme disease, so if you’re bitten, you should visit a doctor immediately. You may also experience flu-like symptoms or joint pains in the first month after the bite.

6. DON'T WAIT TO GET TREATMENT.

If you don't see the tick bite, and don't treat early symptoms, the spirochetes continue to spread throughout your body and can cause more severe symptoms, including fatigue, stiff or aching neck, tingling or numbness in your extremities, and even paralysis of your face. Even more debilitating symptoms of later-stage Lyme disease can include severe headaches, painful arthritis and swelling of joints, cardiac abnormalities, and central nervous system debilitations leading to cognitive disorders.

7. IF CAUGHT EARLY, IT'S USUALLY HIGHLY TREATABLE …

When the disease is caught in its early stages, and treated with antibiotics, it’s curable, Sellati says. Even later stages of the disease can be treated, but the longer an infection goes untreated, the more severe the symptoms and damage can become.

8. … BUT SOME PATIENTS EXPERIENCE SYMPTOMS FOR MUCH LONGER.

Scientists are not entirely sure why a subset of patients have recurrent symptoms of the illness in the months and even years following treatment, known as post-treatment Lyme disease syndrome. “It’s not clear if there is a persistence of live replicating bacteria in some immune privileged niche where they’re protected from exposure to antibiotics,” Sellati says, or if it’s simply the subsequent inflammation stirred up in the body that refuses to go back to normal. “What drives that is not entirely clear.”

9. YOUR GENETICS MAY DICTATE YOUR TREATMENT.

Sellati’s lab has been exploring whether genetics plays a role in who recovers after treatment and who doesn’t. “We have some evidence that your genetic makeup can actually predispose you to developing post-treatment Lyme disease syndrome," Sellati says, and adds it will require more research. They believe they might be able to isolate genetic markers that will tell doctors if antibiotics alone will work, or if the patient might need additional treatment.

10. FEAR THE ENGORGED TICK (BUT DON'T PANIC).

The good news is, even if a tick bites you, if it isn’t yet fully engorged on your blood, chances are good it hasn’t been there long enough to transmit the spirochetes that lead to infection. However, it’s always better to be safe, and pay attention to any symptoms that occur thereafter. “The sooner you can remove a tick from your body, whether it’s feeding or not, the better. If the tick is feeding for less than 24 hours, the likelihood of being infected with Borellia is significantly reduced,” Sellati says.

11. AREAS WITH MICE HAVE MORE LYME DISEASE.

Wherever you find mice and deer you’re very likely to find ticks as well. In fact, Sellati says, mice in all forms—but especially the white-footed mouse—are what infectious researchers call a “maintenance reservoir.” Sellati says. “They maintain the bacteria in the wild so that new ticks can acquire it.” Since spirochetes tend to stay in the bloodstream of mice much longer than they do in humans, that’s how ticks have such an endless supply of the bacteria. “If you got rid of all the mice in the world, you would either come very close to or significantly reduce the population of Borellia in the environment. You’d have a significant decrease in Lyme,” he emphasizes.

12. YOU CAN TAKE SIMPLE STEPS TO PROTECT YOURSELF.

Wear clothes with the most coverage possible. Spray yourself with anti-tick sprays. But no matter what, always do a tick check after you return from the outdoors just to be safe. And if you start to feel any of the symptoms mentioned earlier within a month of a tick bite, don’t wait to visit your doctor.

13. CHECK YOUR CREVICES.

Ticks are not opposed to biting you wherever they can reach, but they have a preference for your warm, moist crevices, such as armpits, backs of the knee, groin, base of the head, and nape of your neck.

14. SKIP SOME OF THOSE "TIPS" FOR REMOVING TICKS THAT YOU'VE HEARD ABOUT.

No matter how many YouTube tutorials you’ve watched, Sellati recommends that you do not use heat, like a match or a lighter, to burn a tick off. The same goes for “goops” such as petroleum jelly, alcohol, or hand sanitizer. Since the spirochetes are transmitted through tick saliva, Sellati warns, “If you try to do those things, you’re only going to piss the tick off, and a pissed-off tick spits a lot, and you're more likely to get more bacteria into your bloodstream.”

15. INSTEAD, USE SLOW, STEADY PRESSURE—AND SOME TWEEZERS.

Take a small pair of forceps or tweezers, Sellati instructs, and gently grasp the tick as close to the skin’s surface as possible, “then pull the tick straight up slowly, which pulls the mouth part out of the skin, and then just dab the area with alcohol to disinfect.” A tick’s mouthparts are like tiny barbed hooks, designed to pierce the skin and stay there. “Then they have secretions that cement the mouthparts to the skin, because they have to feed over a long time and they don’t want to be knocked off while they sit and sip.”

nextArticle.image_alt|e
iStock
These Sparrows Have Been Singing the Same Songs for 1500 Years
iStock
iStock

Swamp sparrows are creatures of habit—so much so that they’ve been chirping out the same few tunes for more than 1500 years, Science magazine reports.

These findings, published in the journal Nature Communications, resulted from an analysis of the songs of 615 adult male swamp sparrows found in six different areas of the northeastern U.S. Researchers learned that young swamp sparrows pick up these songs from the adults around them and are able to mimic the notes with astounding accuracy.

Here’s what one of their songs sounds like:

“We were able to show that swamp sparrows very rarely make mistakes when they learn their songs, and they don't just learn songs at random; they pick up commoner songs rather than rarer songs,” Robert Lachlan, a biologist at London’s Queen Mary University and the study’s lead author, tells National Geographic.

Put differently, the birds don’t mimic every song their elders crank out. Instead, they memorize the ones they hear most often, and scientists say this form of “conformist bias” was previously thought to be a uniquely human behavior.

Using acoustic analysis software, researchers broke down each individual note of the sparrows’ songs—160 different syllables in total—and discovered that only 2 percent of sparrows deviated from the norm. They then used a statistical method to determine how the songs would have evolved over time. With recordings from 2009 and the 1970s, they were able to estimate that the oldest swamp sparrow songs date back 1537 years on average.

The swamp sparrow’s dedication to accuracy sets the species apart from other songbirds, according to researchers. “Among songbirds, it is clear that some species of birds learn precisely, such as swamp sparrows, while others rarely learn all parts of a demonstrator’s song precisely,” they write.

According to the Audubon Guide to North American Birds, swamp sparrows are similar to other sparrows, like the Lincoln’s sparrow, song sparrow, and chipping sparrow. They’re frequently found in marshes throughout the Northeast and Midwest, as well as much of Canada. They’re known for their piercing call notes and may respond to birders who make loud squeaking sounds in their habitat.

[h/t Science magazine]

nextArticle.image_alt|e
iStock
10 Scientific Benefits of Being a Dog Owner
iStock
iStock

The bickering between cat people and dog people is ongoing and vicious, but in the end, we're all better off for loving a pet. But if anyone tries to poo-poo your pooch, know that there are some scientific reasons that they're man's best friend.

1. YOU GET SICK LESS OFTEN.

Dog snuggling on a bed with its person.
iStock

If cleaning commercials are to be believed, humanity is in the midst of a war against germs—and we shouldn't stop until every single one is dead. In reality, the amount of disinfecting we do is making us sicker; since our bodies are exposed to a less diverse mix of germs, our entire microbiome is messed up. Fortunately, dogs are covered in germs! Having a dog in the house means more diverse bacteria enters the home and gets inside the occupants (one study found "dog-related biodiversity" is especially high on pillowcases). In turn, people with dogs seem to get ill less frequently and less severely than people—especially children—with cats or no pets.

2. YOU'RE MORE RESISTANT TO ALLERGIES.

Child and mother playing with a dog on a bed.
iStock

While dog dander can be a trigger for people with allergies, growing up in a house with a dog makes children less likely to develop allergies over the course of their lives. And the benefits can start during gestation; a 2017 study published in the journal Microbiome found that a bacterial exchange happened between women who lived with pets (largely dogs) during pregnancy and their children, regardless of type of birth or whether the child was breastfed, and even if the pet was not in the home after the birth of the child. Those children tested had two bacteria, Ruminococcus and Oscillospira, that reduce the risk of common allergies, asthma, and obesity, and they were less likely to develop eczema.

3. YOU'LL HAVE BETTER HEART HEALTH.

Woman doing yoga with her dog.
iStock

Everything about owning a dog seems to lend itself to better heart health. Just the act of petting a dog lowers heart rate and blood pressure. A 2017 Chinese study found a link between dog ownership and reduced risk of coronary artery disease, while other studies show pet owners have slightly lower cholesterol and are more likely to survive a heart attack.

4. YOU GET MORE EXERCISE.

Person running in field with a dog.
iStock

While other pets have positive effects on your health as well, dogs have the added benefit of needing to be walked and played with numerous times a day. This means that many dog owners are getting 30 minutes of exercise a day, lowering their risk of cardiovascular disease.

5. YOU'LL BE HAPPIER.

Woman cuddling her dog.
iStock

Dog owners are less likely to suffer from depression than non-pet owners. Even for those people who are clinically depressed, having a pet to take care of can help them out of a depressive episode. Since taking care of a dog requires a routine and forces you to stay at least a little active, dog owners are more likely to interact with others and have an increased sense of well-being while tending to their pet. The interaction with and love received from a dog can also help people stay positive. Even the mere act of looking at your pet increases the amount of oxytocin, the "feel good" chemical, in the brain.

6. YOU HAVE A MORE ACTIVE SOCIAL LIFE.

Large bulldog licking a laughing man.
iStock

Not only does dog ownership indirectly tell others that you're trustworthy, your trusty companion can help facilitate friendships and social networks. A 2015 study published in PLOS One found that dogs can be both the catalyst for sparking new relationships and also the means for keeping social networks thriving. One study even showed that those with dogs also had closer and more supportive relationships with the people in their lives.

7. YOUR DOG MIGHT BE A CANCER DETECTOR.

Man high-fiving his dog.
iStock

Your dog could save your life one day: It seems that our canine friends have the ability to smell cancer in the human body. Stories abound of owners whose dogs kept sniffing or licking a mole or lump on their body so they got it checked out, discovering it was cancerous. The anecdotal evidence has been backed up by scientific studies, and some dogs are now trained to detect cancer.

8. YOU'LL BE LESS STRESSED AT WORK.

Woman working on a computer while petting a dog.
iStock

The benefits of bringing a dog to work are so increasingly obvious that more companies are catching on. Studies show that people who interact with a pet while working have lower stress levels throughout the day, while people who do not bring a pet see their stress levels increase over time. Dogs in the office also lead to people taking more breaks, to play with or walk the dog, which makes them more energized when they return to work. This, in turn, has been shown to lead to much greater productivity and job satisfaction.

9. YOU CAN FIND OUT MORE ABOUT YOUR PERSONALITY.

Man running in surf with dog.
iStock

The kind of dog you have says a lot about your personality. A study in England found a very clear correlation between people's personalities and what type of dogs they owned; for example, people who owned toy dogs tended to be more intelligent, while owners of utility dogs like Dalmatians and bulldogs were the most conscientious. Other studies have found that dog owners in general are more outgoing and friendly than cat owners.

10. YOUR KIDS WILL BE MORE EMPATHETIC.

A young boy having fun with his dog.
iStock

Though one 2003 study found that there is no link between pet ownership and empathy in a group of children, a 2017 study of 1000 7-12 year olds found that pet attachment of any kind encouraged compassion and positive attitudes toward animals, which promoted better well-being for both the child and the pet. Children with dogs scored the highest for pet attachment, and the study notes that "dogs may help children to regulate their emotions because they can trigger and respond to a child's attachment related behavior." And, of course, only one pet will happily play fetch with a toddler.

A version of this story originally ran in 2015.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios