10 Secrets of Epidemiologists

Epidemiologists are fans of charts.
Epidemiologists are fans of charts.
metamorworks/iStock via Getty Images

Unless you know an epidemiologist or are one yourself, those “disease detectives” might not have occupied a very large portion of your brain. Last year, that is. Now, with the coronavirus pandemic at the top of mind—and at the top of so many headlines—there’s a good chance you’re at least aware that epidemiologists study diseases.

To be more specific, the Centers for Disease Control and Prevention (CDC) defines epidemiology as “the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems.” So what exactly does this mean? Mental Floss spoke with a few epidemiologists to shed light on what they do, how they do it, and which germ-friendly foods they avoid at the buffet.

1. People often mistake epidemiologists for skin doctors.

Since the word epidemiologist sounds like it might have something to do with epidermis (the outer layer of skin), people often think epidemiology is some offshoot of dermatology. At least, until the coronavirus pandemic.

“Prior to that, no one knew what I did. Everyone was like ‘Oh you’re an epidemiologist—do you work with skin?’” Sarah Perramant, an epidemiologist at the Passaic County Department of Health Services in New Jersey, tells Mental Floss. “I would be rich if I had a dollar for every time I got asked if I work with dermatologists.”

2. Epidemiologists don’t discover a new disease every day.

Though some epidemiologists do look for unknown diseases—certain zoonotic epidemiologists, for example, surveil wildlife for animal pathogens that might jump to humans—most are dealing with diseases that we’re already familiar with. So what do they do every day? It varies … a lot.

Epidemiologists who work at academic or research institutions undertake research projects that help determine how a disease spreads, which behaviors put you at risk for it, and other unknowns about anything from common colds to cancer. But it’s not just about devising experiments and studying patient data.

“I like to tell my friends and family that my job is about four different jobs in one,” Dr. Lauren McCullough, an assistant professor in the department of epidemiology at Emory University’s Rollins School of Public Health, tells Mental Floss.

Writing, she says, is “the most important part.” It includes requesting grants, devising lectures and assignments, grading her students’ work, writing about her research, and more. She also sits on admissions committees, reviews other epidemiologists’ studies, and oversees the many people—project managers, data analysts, technicians, trainees, etc.—working on her own research projects.

Those who work in the public health sphere are often monitoring local outbreaks of diseases like the flu, Lyme disease, salmonellosis, measles, and more. If you test positive for a nationally notifiable disease (any of about 120 diseases that could cause a public health issue), the CDC or your state health department sends your electronic lab report to the epidemiologist in your area, who’s responsible for contacting you, finding out how you got sick, and telling local officials what steps to take in order to prevent it from causing an outbreak.

3. Epidemiologists have to make some uncomfortable phone calls.

At least the person on the other end can't see your expression of consternation.Andrea Piacquadio, Pexels

Epidemiologists sometimes have to ask pretty personal questions about drug use and sexual activity when trying to figure out how someone got infected, and not everyone is happy to answer them. “I’ve gotten hung up on many a time,” Dr. Krys Johnson, an assistant professor in Temple University’s department of epidemiology and biostatistics, tells Mental Floss.

Some simply aren’t willing to accept that they might have been exposed to a disease without knowing it. After several employees at a certain company tested positive for COVID-19, for example, Perramant started calling the rest of the workers to tell them to go into quarantine; this way, she could prevent sick people who weren't yet showing symptoms from spreading the disease without knowing it. But not everybody was open to her advice. “They would just swear up and down, ‘I haven’t been in touch with anybody who’s positive, please don’t call me again,’” Perramant says.

But there are plenty of cooperative people, too, especially victims of foodborne or diarrheal illnesses. “They really want to know where they got sick because they’re so miserable that they never, ever want to deal with that again,” Johnson explains. Parents of sick kids are also generally forthcoming, since they want to keep their kids healthy in the future. And then there are those who don’t have any problem spilling their secrets to a stranger.

“There was one woman who was very memorable,” Johnson says. “I called her about her Hepatitis C, and she was like, ‘Oh, honey, I did drugs back in the ’80s. That’s where I got my Hepatitis C. I pop positive every time!’”

4. Epidemiologists deal with a lot of rejection.

Public health epidemiologists have to learn to just shrug off all the rude tones and dial tones, and epidemiologists in academic settings need thick skin for different reasons.

“There’s just a lot of rejection,” McCullough says. “‘That idea isn’t good enough; this paper isn’t good enough; you’re not good enough.’ That is just a resounding thing. There’s a high bar for science; there’s a high bar for federal funding; and it takes a lot to cross that bar. So in the academic setting at these top-tier institutions, you really just have to have a thick skin.”

5. Just because epidemiologists' guidelines change doesn't mean they're wrong.

Sometimes, McCullough explains, the story of a disease can change over the course of one study. When you look at the first 100 people in a 10,000-person study, you’ll see one story emerge. By the time you’ve seen 1000 people, that story looks different. And after you’ve seen the data from all 10,000 people, the original story might not be accurate at all.

Usually, epidemiologists can complete the whole study of a disease and draw conclusions without the world clamoring for half-baked answers. But with a brand-new, highly infectious disease like COVID-19, epidemiologists don’t have that luxury. As they’ve learned more about how the pathogens spread, how long they can survive on surfaces, and other factors, they’ve changed their recommendations for safety precautions. Everyone else in the world of epidemiology expected this to happen, but the general public did not.

“If we say something this week that contradicts what we said last week, it’s not that we were wrong,” Johnson says. “It’s that we learned something between those two time points.”

6. Being an epidemiologist would be easier if people kept better track of their behavior.

Often, people omit vital information about how they got exposed to an illness because they just don’t remember all the details. You could easily recall devouring a few slices of the decadent chocolate cake your mom baked for your birthday last Friday, but you might not be able to name every bite of food you ate on a random Thursday three weeks ago.

“People aren’t telling us the whole truth, but it’s not that they’re being intentionally obtuse,” Johnson explains. “With recall bias, unless there’s a reason for us to really remember, we’re not going to remember everything we actually ate.”

This has made it especially difficult to trace an aerosolized disease like COVID-19.

“All my friends going into the Fourth of July were like, ‘Should we have a get-together?’” Perramant says. “And I said, ‘You can have people over, but you better take an attendance list. You better have a little spreadsheet on Google Drive that has every person’s name and their phone number, so that when one person tests positive and gets sick this week, when I call you, you will be able to give me that information like that.’”

7. Epidemiologists have reason to be wary of buffets, cruise ships, mayonnaise, and cubed ham.

It's all fun and games until someone eats warm egg salad.Tim Meyer, Unsplash

Infectious disease epidemiologists may have accepted that germs are a part of life, but they also know where those germs like to congregate.

“I don’t go to buffets, I have never been on a cruise ship and I don’t intend to, I’m super conscientious when I fly,” Johnson says. “And I’m really aware of whenever mayonnaise-based things are put out at family functions. If you’re ever at a potluck and people come down sick, the first thing people say [they ate] is potato salad or egg salad, because mayonnaise can spoil so quickly.”

“[Cubed ham] is one particular microbe’s very favorite thing to multiply on, so if you’re gonna have ham, make it a whole ham,” she says.

8. Teaching people is a really rewarding part of being an epidemiologist.

In addition to actually leading lectures in the classroom, academic epidemiologists also work extremely closely with their students on research projects; McCullough estimates that she’s in contact with hers at least once a day when they’re collaborating on a study.

“To work with someone so closely, and to watch them progress as a scientist and as a person, and then to have to let them go and send them out into the world, I find that very rewarding,” McCullough says of her trainees. “As a scientist in an academic institution, there’s not a whole lot of immediate gratification. Our papers get rejected, our grants don’t get funded, but the trainees are always a source of immediate gratification for me, so I hold them close to my heart.”

Epidemiologists in other spheres have teaching opportunities, too. When a community experiences a disease outbreak, public health epidemiologists like Perramant are responsible for helping the general public understand what they can do to prevent the spread.

“I like to teach kids about infectious disease and infection prevention for what’s relevant to them. We’ve had a couple of large outbreaks at summer camps, and last summer I put together a training for camp counselors,” Perramant says. “That’s always a part of my job that I really love.”

9. Epidemiologists have a unique understanding of racial disparities.

At this point, it's exceptionally clear that COVID-19 is disproportionately affecting people of color in the U.S. They're more likely to be exposed to it, they have less access to testing, and the preexisting conditions that place them at a higher risk can be the result of systemic racism. When these trends started to become apparent, McCullough got flooded with phone calls asking why. Her answer? This isn’t new. As she’s seen in her work as a breast cancer researcher, Black women are more likely to die of that disease than their white counterparts, and similar health disparities exist across the board.

McCullough explains that the general public is finally realizing what epidemiologists already knew: That poor disease outcomes in minority, low-income, and rural populations aren’t because of anything those people are doing on an individual level. Instead, it’s a result of systemic issues that keep them from leading financially comfortable, healthy lifestyles with access to healthcare and other resources.

“It’s not just COVID—it’s almost every single chronic and infection ailment that’s out there,” McCullough explains. “So this is a real opportunity for people to step back and take an assessment of where we are in terms of our healthcare system, and what we’re doing so that everybody has equitable outcomes. Because people shouldn’t die just because they live in a rural area, or just because they’re poor, or just because they’re Black or Hispanic.”

10. They've had to deal with a lot of “armchair epidemiologists” lately.

Until this year, epidemiologists had to suffer through people mistaking them for dermatologists. Now, during the coronavirus pandemic, people finally know at least a little about their jobs. In fact, people are so confident in their newfound epidemiological knowledge that many are fancying themselves experts on the subject.

“At the beginning of 2020, there were like 500 epidemiologists, and now there are about 5 million. Everybody thinks they’re an epidemiologist,” McCullough says. “There’s a science to it, and it’s a science that requires training. We went to school for a really long time to be doctorally trained epidemiologists.”

It’s not just about advanced degrees, either. Beyond that, you need years of firsthand experience to grasp all the nuances of understanding methods, interpreting data, translating your findings into recommendations for the general public, and so much more. In short, you can’t just decide you’re an epidemiologist.

Perramant has her own analogy for the recent influx of self-proclaimed epidemiologists: “It’s like armchair psychology. Poolside epidemiology now is a thing.”

10 of the Best Indoor and Outdoor Heaters on Amazon

Mr. Heater/Amazon
Mr. Heater/Amazon

With the colder months just around the corner, you might want to start thinking about investing in an indoor or outdoor heater. Indoor heaters not only provide a boost of heat for drafty spaces, but they can also be a money-saver, allowing you to actively control the heat based on the rooms you’re using. Outdoor heaters, meanwhile, can help you take advantage of cold-weather activities like camping or tailgating without having to call it quits because your extremities have gone numb. Check out this list of some of Amazon’s highest-rated indoor and outdoor heaters so you can spend less time shivering this winter and more time enjoying what the season has to offer.

Indoor Heaters

1. Lasko Ceramic Portable Heater; $20

Lasko/Amazon

This 1500-watt heater from Lasko may only be nine inches tall, but it can heat up to 300 square feet of space. With 11 temperature settings and three quiet settings—for high heat, low heat, and fan only—it’s a dynamic powerhouse that’ll keep you toasty all season long.

Buy it: Amazon

2. Alrocket Oscillating Space Heater; $25

Alrocket/Amazon

Alrocket’s oscillating space heater is an excellent addition to any desk or nightstand. Using energy-saving ceramic technology, this heater is made of fire-resistant material, and its special “tip-over” safety feature forces it to turn off if it falls over (making it a reliable choice for homes with kids or pets). It’s extremely quiet, too—at only 45 dB, it’s just a touch louder than a whisper. According to one reviewer, this an ideal option for a “very quiet but powerful” heater.

Buy it: Amazon

3. De’Longhi Oil-Filled Radiator Space Heather; $79

De’Longhi/Amazon

If you prefer a space heater with a more old-fashioned vibe, this radiator heater from De’Longhi gives you 2020 technology with a vintage feel. De’Longhi’s heater automatically turns itself on when the temperatures drops below 44°F, and it will also automatically turn itself off if it starts to overheat. Another smart safety feature? The oil system is permanently sealed, so you won’t have to worry about accidental spills.

Buy it: Amazon

4. Aikoper Ceramic Tower Heater; $70

Aikoper/Amazon

Whether your room needs a little extra warmth or its own heat source, Aikoper’s incredibly precise space heater has got you covered. With a range of 40-95°F, it adjusts by one-degree intervals, giving you the specific level of heat you want. It also has an option for running on an eight-hour timer, ensuring that it will only run when you need it.

Buy it: Amazon

5. Isiler Space Heater; $37

Isiler/Amazon

For a space heater that adds a fun pop of color to any room, check out this yellow unit from Isiler. Made from fire-resistant ceramic, Isiler’s heater can start warming up a space within seconds. It’s positioned on a triangular stand that creates an optimal angle for hot air to start circulating, rendering it so effective that, as one reviewer put it, “This heater needs to say ‘mighty’ in its description.”

Buy it: Amazon

Outdoor Heaters

6. Mr. Heater Portable Buddy; $104

Mr. Heater/Amazon

Make outdoor activities like camping and grilling last longer with Mr. Heater’s indoor/outdoor portable heater. This heater can connect to a propane tank or to a disposable cylinder, allowing you to keep it in one place or take it on the go. With such a versatile range of uses, this heater will—true to its name—become your best buddy when the temperature starts to drop.

Buy it: Amazon

7. Hiland Pyramid Patio Propane Heater; Various

Hiland/Amazon

The cold’s got nothing on this powerful outdoor heater. Hiland’s patio heater has a whopping 40,000 BTU output, which runs for eight to 10 hours on high heat. Simply open the heater’s bottom door to insert a propane tank, power it on, and sit back to let it warm up your backyard. The bright, contained flame from the propane doubles as an outdoor light.

Buy it: Amazon

8. Solo Stove Bonfire Pit; $345

Solo Stove/Amazon

This one is a slight cheat since it’s a bonfire pit and not a traditional outdoor heater, but the Solo Stove has a 4.7-star rating on Amazon for a reason. Everything about this portable fire pit is meticulously crafted to maximize airflow while it's lit, from its double-wall construction to its bottom air vents. These features all work together to help the logs burn more completely while emitting far less smoke than other pits. It’s the best choice for anyone who wants both warmth and ambiance on their patio.

Buy it: Amazon

9. Dr. Infrared Garage Shop Heater; $119

Dr. Infrared/Amazon

You’ll be able to use your garage or basement workshop all season long with this durable heater from Dr. Infrared. It’s unique in that it includes a built-in fan to keep warm air flowing—something that’s especially handy if you need to work without wearing gloves. The fan is overlaid with heat and finger-protectant grills, keeping you safe while it’s powered on.

Buy it: Amazon

10. Mr. Heater 540 Degree Tank Top; $86

Mr. Heater/Amazon

Mr. Heater’s clever propane tank top automatically connects to its fuel source, saving you from having to bring any extra attachments with you on the road. With three heat settings that can get up to 45,000 BTU, the top can rotate 360 degrees to give you the perfect angle of heat you need to stay cozy. According to a reviewer, for a no-fuss outdoor heater, “This baby is super easy to light, comes fully assembled … and man, does it put out the heat.”

Buy it: Amazon

Sign Up Today: Get exclusive deals, product news, reviews, and more with the Mental Floss Smart Shopping newsletter!

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

11 Secrets of Astronauts

Wikimedia Commons, Public Domain
Wikimedia Commons, Public Domain

In the 60 or so years that the job has existed, astronauts have captured the public's imagination. And while many people might think they have some idea of what being an astronaut is like, thanks to the glut of portrayals in movies, real astronauts will tell you that working for NASA is much different from what you see on the screen. In between exciting tasks like spacewalks, they have to worry about less glamorous aspects of the job—like finding lost items that floated away and using the toilet in microgravity.

Mental Floss spoke with two former NASA astronauts about the realities of preparing for and experiencing life in space. Read on to learn about the most annoying parts of the job, the ways they have fun, and their honest opinions about astronaut food.

1. Astronauts come from a range of different fields.

There’s no one direct path to becoming an astronaut. If someone knows they want to be an astronaut from a young age, they need to build credentials in a specific field before they can get the attention of NASA. "They're looking for people who are qualified, meaning that they're high-achieving military people or people from civilian life, generally with an advanced degree," Mike Massimino, a former NASA astronaut and professor of mechanical engineering at Columbia University, tells Mental Floss.

To be considered for NASA’s astronaut program, candidates must have U.S. citizenship, hold a master's degree in a STEM field, and have at least two years of related post-grad professional experience or at least 1000 hours of pilot-in-command time on jet aircraft. Two years toward a doctoral program in STEM, a completed doctor of medicine or doctor of osteopathic medicine degree, or completion of a nationally recognized test pilot school program are also accepted in place of a master's degree. Because space flight crews require diverse skill sets, the criteria doesn’t get more specific than that.

"I was a Ph.D. research engineer professor when I was picked," Massimino says. "I've flown in space with engineers, with test pilots, helicopter pilots for the military. I've also flown in space with a geologist, I've flown in space with an oceanographer, and I've flown in space with a veterinarian. So it's really varied. There's not just one route."

2. Astronaut training involves everything from class work to military survival exercises.

NASA astronaut Garrett Reisman on a spacewalk in May 2010.NASA's Marshall Space Flight Center, Flickr // CC BY-NC 2.0

Candidates accepted into the astronaut program must complete years of training before they're ready for spaceflight. A lot of that training takes place in the classroom and involves learning about different space vehicles and systems. Astronauts also undergo physical training in the real world. According to Garrett Reisman, former NASA astronaut and the director of space operations at SpaceX's headquarters in Hawthorne, California, one of the most intense courses has nothing to do with preparing for life in space.

"We do the same SERE [survive, evade, resist, escape] training that military aviators go through," he tells Mental Floss. "The idea is that if you fell out of an aircraft over enemy terrain, you got to know how to survive without help. You have to learn to live off the land, what plants you can eat, how to make a shelter and all those things."

The T-38 jets astronauts fly as part of their training have ejectable seats, so landing somewhere unfamiliar is a possibility. But astronauts only fly over the continental U.S., so they likely won't ever need to use the full extent of their SERE training. "What are the odds that you parachute down and there’s not a Starbucks right there?" Reisman jokes. "All you need to do is give me a Starbucks gift card and I’ll be fine."

3. Exercise is a vital part of the job.

Exercising is more than a way to pass time in space: It’s essential to an astronaut’s health. The human body isn’t used to moving around without the force of gravity, and for this reason, all astronauts must make resistance exercises part of their daily routine.

"You do have to spend two hours every day exercising," Reisman says. "If you're up there for a long period of time, you can lose a lot of your bone and your muscle mass if you do nothing, so the way we get around that is by doing intense resistance exercise."

Astronauts can lose up to 20 percent of their muscle mass on an 11-day space flight due to the lack of gravity [PDF]. But zero gravity also makes free weights useless, so instead, astronauts maintain their strength by using a device outfitted with two small canisters that create a vacuum they can pull against with a long bar. A bike and treadmill (with a harness) are also available on the International Space Station. Strength is required to perform certain emergency procedures when the ship re-enters Earth's gravitational field, so staying fit in space is vital.

4. Astronauts do most of their work on Earth.

Astronaut Mike Massimino practices repairing a portion of the Hubble Space Telescope while training at NASA's Johnson Space Center in Houston, Texas.NASA Hubble Space Telescope, Flickr // CC BY 2.0

In order to become one of the few people to travel to space, astronauts must be willing to do a lot of work at home. "A NASA astronaut’s job is mainly spending your time on Earth," Massimino says. "You're going to spend the vast majority of your time on the ground, either training or working on technical issues or helping other people fly." Throughout his nearly two decades with NASA, Massimino spent less than a month total in space. Reisman was with NASA for 12 years and spent a cumulative 107 days of his career in space.

5. Astronauts don't make as much money as you think.

One of the biggest misconceptions astronauts hear about their work relates to their salary. While they are paid decently, astronauts don’t collect the massive paychecks some people might assume comes with such a high-profile job. "We don't make a heck of a lot of money," Massimino says. "We make a standard government salary."

Astronauts are paid according to the federal government's General Schedule pay scale. Most federal jobs are assigned a General Schedule (GS) grade that determines their starting salary, and the pay increases as they gain experience. Astronauts either qualify for grades GS 13 or 14 (the highest grade is GS 15) and make between $104,898 and $161,141 per year. For comparison, Fish and Wildlife administrators are paid similarly at the right experience level.

6. Astronauts lose things (but not for long).

Even in a place as tight as a space station, astronauts still manage to misplace their belongings. Thanks to the lack of gravity, anything they let go of immediately drifts away, which can cause problems when they’re not paying attention. Massimino recalls one incident that happened to his crewmate Mike Good: "He had his grandfather’s watch with him, and he comes up to me and goes, 'Mass, I can’t find the watch.' We’re looking all over the place and I stop after a minute and go, 'Mike, it’s inside here somewhere.'"

They eventually found it trapped inside the airlock. The air filter is another common place where lost items end up: Without gravity interfering, the air flow will carry any floating objects there. "One thing we would say is, 'If you can’t find something, just wait,'" Massimino says. "You'd wake up in the morning and look at the filter and see like aspirin and a piece of Velcro or something, because everything eventually would get there."

7. Astronaut opinions on the food in space are mixed.

Despite its reputation, space food has some fans in the astronaut community. "Astronaut food is great," Massimino says. "We had ravioli, lasagna, shrimp cocktail, fajitas. It was fantastic."

Reisman holds a much different opinion of the meals he ate in space. "It’s terrible. You don’t go to the space station for the food," he says. While he didn’t love the American and Russian provisions that made up most of his diet in space, he did have nice things to say about food from other agencies. "The Japanese and the Europeans, when their astronauts would fly, they had special food that was provided by their space agencies. The Japanese sent up yakitori and miso soup and that was delicious. And the Europeans had pâté. That was much better."

8. Astronauts find time to have fun.

NASA astronaut Mike Massimino smiles during some extravehicular activity (EVA).NASA Hubble Space Telescope, Flickr // CC BY 2.0

Between work, meals, and exercise, astronauts don’t have a ton of free time in space. Duties like maintenance, installing equipment, and conducting experiments take up the majority of their day. Sneaking in recreation usually means staying up past their scheduled bedtime, which Reisman confirms most astronauts do. One of his favorite activities to do aboard the International Space Station was taking pictures of Earth. "You could take photographs of places on Earth that are special to you. I got a picture of my hometown, which is pretty cool. As far as I know, no human ever photographed that particular town from space before."

9. Astronauts think movies set unrealistic standards.

The science isn’t the only thing that’s unrealistic about Hollywood’s portrayal of space travel. "I think the biggest misconception is that we're all tall and good-looking," Reisman says. When working as a technical advisor for 2019's Ad Astra, he jokingly brought up this gripe with the movie’s star Brad Pitt. "I said, 'I’m kind of pissed off at you. Think about who they cast to be astronauts in all these movies and TV shows. Matt Damon, Matthew McConaughey, George Clooney, Brad Pitt. People meet me and they’re disappointed.'"

Reisman doesn't hold this against the actors, however. Pitt reminded him that the stars portraying astronauts on screen have plenty to be envious of themselves. "Brad said: 'Well, Garrett, I can't actually fly a spaceship. The only talent I have is being able to stand in a certain spot and read something that someone else wrote. I got nothing else.'"

10. Going to the bathroom in space is an ordeal.

If you’ve ever wondered how astronauts poop in space, the answer is: with great difficulty. "Taking a dump was not easy," Reisman confirms. Without the help of gravity, using a toilet in space becomes a complicated operation. Astronauts must strap their feet down to keep from floating away and create a perfect seal between the toilet seat and their butt cheeks. The toilet itself uses a vacuum hose to suction up the waste. The process is so complex that using a space toilet is part of an astronaut’s training. It's not unusual for a bathroom break that normally takes a few minutes on Earth to last half an hour in space.

11. In such a competitive field, astronauts need to be persistent.

NASA's astronaut training program is extremely competitive. The agency selected just 12 people out of a pool of 18,353 candidates in 2017, which comes out to an acceptance rate of 0.065 percent. Massimino had to apply four times before he made it into the program.

"I was rejected outright twice while I was in grad school. The third time I got an interview and failed the eye exam, so was medically disqualified." NASA considers candidates with less than 20/20 vision today as long as it's correctable, but that wasn't the case when Massimino was applying. "I went through some vision training with an optometrist, and I was able to teach my eyes to see a little better. I was able to apply a fourth time, and I was picked on my fourth try."

According to Massimino, that level of commitment to his goal ended up being relevant to the job itself. "The job is a lot of late-night simulations, you have to pass exams, you have to work with your teammates. And unless you have a real interest in it, it's going to be tough."