Month: September 2023

The media uproar that swirled a few weeks ago around leprosy in the US drew attention away from ongoing heat and extreme weather that pose far more danger to most of us. But does a single case of a man diagnosed with leprosy in central Florida suggest that anyone anywhere in the US could get leprosy? Might this become the next pandemic? Just how worried should we be?

Read on to set the record straight about leprosy. (Spoiler alert: there will be mention of armadillos.)

Why did leprosy make the news?

In August, one case of leprosy in central Florida was described in the journal Emerging Infectious Diseases. This report was widely covered by the news media, with headlines like “CDC confirms leprosy outbreak in Florida: What to know if you’re traveling to the state” (WKYC) and “Central Florida is a hot spot for leprosy, report says” (CNN).

One reason for concern raised by experts was the fact that the man diagnosed had no identifiable risk factors for the disease. That is, he had not traveled to a place where leprosy is common and had no contact with anyone who had the disease. Past research has suggested the organism that causes leprosy can survive in soil. And that raised the possibility that this man’s work as a landscaper put him at risk for leprosy.

What is leprosy?

Leprosy, or Hansen’s disease, is a chronic infection caused by Mycobacterium leprae bacteria. (That’s a close relative of the organism that causes tuberculosis.) This ancient disease, which affects skin, nerves, and linings of the eyes and upper respiratory tract, is described in some of the earliest human writings (including the Old Testament), and genetically identified in archeological remains dating back to 2000 BC.

Common symptoms of leprosy include:

• red and/or thickened patches on the skin
• reduced sensation, numbness, or weakness in the hands or feet
• nonhealing wounds, blisters, and cracks in the skin of the hands or feet.

Left untreated, this may lead to skin deformities. Surgical amputations may be necessary to control skin ulcers that fail to heal or are chronically infected.

How does leprosy spread?

Usually, the infection spreads from person to person through respiratory droplets shared during prolonged, close contact. Coughing or sneezing, for example, can release respiratory droplets, which can be breathed in by people who are nearby.

Some cases of leprosy have been linked to animal contact, such as the nine-banded armadillo and Eurasian red squirrels.

However, in about a third of cases, no clear risk factor can be identified.

How common is leprosy?

For most people in the US, leprosy is not a major health concern. In recent years, about 180 cases of leprosy have been diagnosed annually. Though this represents an uptick from fewer than 100 cases in 1999 and 2000, the disease remains rare in the US.

Worldwide, it’s a different story: according to the World Health Organization, more than 200,000 cases in 120 countries are diagnosed each year. The highest numbers of cases are in Brazil, India, and Indonesia.

Has leprosy become common in Florida?

No. There have been about 20 cases per year in Florida since 2015. As is true nationally, this represents an increase from prior years.

But some experts speculate that leprosy may be endemic now in central Florida, where about 80% of the state’s cases are diagnosed. Endemic means there are enough sources of infection (such as infected people or animals) in a particular area to allow the disease to spread, even if no new cases are brought in from elsewhere.

Since some people with infection have no risk factors for the disease, it’s possible leprosy has become endemic there. But that remains unproven.

Myth versus truth: Common misconceptions about leprosy

Misunderstanding fuels stigma and discrimination against people who have leprosy. Maybe you’ve heard some of these falsehoods.

The myth: Leprosy is extremely easy to spread. In the past, this myth led to isolation of people with leprosy in “leper colonies” that quarantined entire communities of people with the infection.

The facts: About 95% of people are naturally immune to leprosy. And, because spread of infection between people requires close and prolonged contact, it’s not nearly as contagious as many other infections. So it’s not readily spread by being in a room with an infected person, or by touch. And, within one week of treatment (see below), a person with leprosy is no longer contagious. As a result, isolation from others is unnecessary.

The myth: Leprosy causes parts of the body, such as fingers or ears or the nose, to fall off.

The facts: Body parts do not fall off. Sometimes surgical amputations are needed to treat nonhealing wounds and infections, two complications of longstanding nerve damage related to leprosy.

The myth: There are no treatments for leprosy.

The facts: There are effective antibiotics for leprosy. To cure the infection, people may need to take a combination of different antibiotics for a year or more.

The bottom line

Some of the news coverage on the case of leprosy in Florida seems more dire than necessary. In fact, the risk of developing leprosy in central Florida, or elsewhere in the US, remains exceedingly low.

And it’s highly unlikely leprosy will become the next pandemic. However, some experts predict that vulnerable populations in the US, such as homeless people living in close contact with poor hygiene and inadequate medical care, could experience outbreaks of leprosy in the future.

While risk seems low now, it’s a good idea to keep leprosy in mind if you have unexplained rashes or nerve damage, especially if you live in a place where the disease is common or have had contact with an infected person. Otherwise, there’s little reason to have leprosy on your short list of health concerns.

Follow me on Twitter @RobShmerling

About the Author

Robert H. Shmerling, MD, Senior Faculty Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing

Dr. Robert H. Shmerling is the former clinical chief of the division of rheumatology at Beth Israel Deaconess Medical Center (BIDMC), and is a current member of the corresponding faculty in medicine at Harvard Medical School. … See Full Bio View all posts by Robert H. Shmerling, MD

The first two weeks of July were the Earth’s hottest on human record, and people across the country continue to suffer from lingering, suffocating heat waves. The US Centers for Disease Control and Prevention has issued repeated warnings and tips about recognizing and preventing heat-related illnesses, like heat stroke, heat exhaustion, and heat cramps.

But one heat-related illness that people do not always recognize is heat rash.

“Heat rash can indicate that your exposure to excessive heat could lead to other serious heat-related issues, if not addressed,” says Dr. Abigail Waldman, a dermatologist with Harvard-affiliated Brigham and Women’s Hospital. "While heat rash is not dangerous in itself, sustained exposure to high heat can lead to heat exhaustion and heat stroke, so it's important to note any early signs that your body is struggling with the heat.”

What are the signs of heat rash?

Heat rash is also known as miliaria or prickly heat. It is caused when ducts from eccrine sweat glands that lead to the skin's surface are blocked or inflamed.

Eccrine sweat glands help your body maintain a steady temperature. When your internal temperature rises, these glands release water that rises to the surface of your skin through tiny ducts. There, it quickly evaporates, cooling your skin and the blood beneath.

However, sweat ducts may get blocked when you sweat excessively in hot temperatures, particularly if skin folds or tight-fitting clothes hinder their function.

Sweat is then trapped beneath the skin. This triggers inflammation, which leads to the appearance of small, itchy red bumps, similar to tiny pimples or blisters. In people with darker skin tones, these small, itchy bumps may not appear red, but will look slightly darker than surrounding skin.

Where and when is heat rash likely to occur?

Heat rash can appear on the neck, scalp, chest, groin, or elbow creases.

“Heat rash can occur any time the body sweats, so it is common in hot, humid climates, during hospitalizations, from fever, and during exercise,” says Dr. Waldman.

Heat rash also can occur in newborns, as their eccrine sweat glands are not fully developed. In newborns, heat rash looks like very thin blisters or water drops widely distributed on the face, trunk, arms, and legs. Call your pediatrician for advice if you notice a rash like this.

How can you treat heat rash?

Heat rash in adults is easy to treat with home remedies. “The techniques to relieve symptoms also can help prevent heat rash for adults and babies,” says Dr. Waldman.

• Cool down. The first step is to get out of the heat and cool and dry your skin. Use a fan or air conditioner, take a cool shower, or apply cool compresses to the affected areas. It's important to know that some people are more vulnerable to heat, and to make plans to help stay safe when temperatures are dangerously high.
• Prevent irritation. To prevent skin irritation, avoid wearing clothes made from synthetic materials, which can trap heat. (While dry-fit clothing helps to wicks away moisture from the skin, it often can be too tight fitting.) Instead, wear light, loose-fitting cotton clothing that allows airflow over your skin. If a heat rash occurs around your groin area, avoid wearing undergarments until it clears up.
• Try anti-itch products. Use an over-the-counter topical corticosteroid cream or calamine lotion for itching. However, avoid baby powder, oily or greasy moisturizers, and sunscreen, as they can further block sweat ducts.

Heat rash typically goes away within one to two days once you cool down your body. More severe heat rashes can last a week or longer. See your doctor (or follow up with your pediatrician) if a heat rash has not cleared up after a week. Also seek immediate care if you experience pain, intense itching, or the rash appears infected.

About the Author

Matthew Solan, Executive Editor, Harvard Men's Health Watch

Matthew Solan is the executive editor of Harvard Men’s Health Watch. He previously served as executive editor for UCLA Health’s Healthy Years and as a contributor to Duke Medicine’s Health News and Weill Cornell Medical College’s … See Full Bio View all posts by Matthew Solan

About the Reviewer

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Dr. Howard LeWine is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio View all posts by Howard E. LeWine, MD

When you’re low on energy, is it worth trying yerba mate, yaupon tea, matcha, and other beverages invading the coffee and tea space that promise similar energy perks and health benefits? Often marketed as wellness drinks, coffee alternatives like these are trending, according to the International Food Information Council.

So, how do a few popular alternatives stack up nutritionally? Do they rely on caffeine for an energy boost? Do they contain potentially healthy (or unhealthy) plant compounds?

The basics on coffee and tea

According to a National Coffee Association survey, 70% of American adults drink coffee, and 62% of those do so daily. Observational studies have linked compounds in coffee beans called polyphenols and antioxidants with health benefits, including a lower risk of type 2 diabetes, heart disease, and neurodegenerative disorders such as Parkinson’s and Alzheimer’s disease. Yet most of us probably don’t drink it for those reasons.

Coffee aficionados enjoy a caffeine energy boost that improves clarity and focus, and savor its fragrance and rich, deep flavor. Still, not everyone is a fan: caffeine makes some people feel jittery, and the caffeine and acidity can irritate sensitive stomachs.

Coffee’s cousin, tea, is the second most popular beverage globally behind water, and is enjoyed by a third of Americans. Most types of tea contain about half the caffeine of coffee (herbal teas have little to none) with less acidity. Tea contains health-promoting antioxidant compounds, such as flavanols.

Caffeine comparison: 8 ounces of brewed coffee contains about 95 mg caffeine; instant coffee about 60 mg; black tea about 47 mg; and green tea about 28 mg.

What to know about yerba mate

Yerba mate (or mate) is an herbal tea from the Ilex paraguariensis tree in South America that has an earthy and more bitter flavor than other teas. It contains antioxidant polyphenols like chlorogenic acid, plus as much caffeine as coffee or more (80 to 175 mg per cup). Preliminary research suggests it might promote weight loss and lower blood cholesterol, but studies are inconclusive. Users report less fatigue and better focus — likely from its caffeine content — but without jitteriness.

Downside: Certain processing methods of mate, such as drying the leaves with smoke, may introduce polycyclic aromatic hydrocarbons — the same carcinogenic substances that are found in grilled meats. Some research links drinking large amounts of mate over time with increased risk of certain cancers, including head and neck, stomach, bladder, and lung. However, unsmoked mate (which is processed by air drying) may be safer.

What to know about yaupon tea

Like mate, yaupon is an herbal tea. Native to the US, it has a mellow grassy flavor similar to green tea. It contains chlorogenic acid and antioxidants that are purported to decrease inflammation and boost energy. This tea has 60 mg caffeine per cup and also provides theobromine, a compound structurally similar to caffeine found in cocoa beans and many teas. Theobromine increases blood flow and may increase energy and alertness, but this boost is slower to start and lasts longer than caffeine, which provides a quick but short-lived boost.

Downside: The combination of theobromine and caffeine may increase heart rate and interfere with sleep, especially if you drink a large amount of yaupon or sip it too close to bedtime.

What to know about matcha tea

Matcha comes from the same Camellia sinensis plant as green tea. However, unlike green tea, matcha is grown in the shade, which protects it from sunlight and oxidation and contributes to its bright green color and higher polyphenol content. Whole tea leaves and stems of matcha are ground into a fine powder, which is then whisked with hot water or milk. Matcha contains about 40 to 175 mg caffeine per cup and has the same antioxidant polyphenols as green tea, specifically theanine and catechins. However, because whole leaves are used to make matcha, it may contain higher concentrations than standard green tea.

Downside: While green tea has low to moderate amounts of caffeine, matcha can have very high amounts, even more than coffee.

What to know about chicory coffee

Chicory is the root of the Chicorium Intybus plant that is dried, roasted, and ground to produce a beverage. Chicory contains prebiotic fiber called inulin that caramelizes during roasting, giving the drink a dark brown color with a nutty, sweeter, and less bitter flavor than traditional coffee. It tastes similar to regular coffee but does not offer the same energy boost, as it is caffeine-free. (Some people mix chicory coffee with brewed coffee for a lower-caffeine drink.) Animal studies show that chicory root has anti-inflammatory properties. Inulin may benefit the gut microbiome and bowel health, but the small amounts found in chicory coffee are not likely to provide such a benefit.

Downside: The chicory plant comes from the same family as ragweed, so chicory coffee may cause allergic reactions in people sensitive to ragweed pollen.

The bottom line

Coffee-alternative wellness drinks may contain similar plant compounds to those found in regular coffee and green or black tea. It’s fine to choose them if you like the taste. Just don’t assume that they’re healthier, because no strong evidence supports claims of weight loss, heart health, or cancer prevention.

These beverages are best enjoyed plain or with only a touch of lemon, honey, unsweetened milk, or plant milk. Processing and added ingredients can negate any health-promoting effects from naturally-occurring plant compounds. For example, some research suggests that adding protein and fat to tea through milk or creamer can reduce antioxidant properties and might deactivate flavonoids. And even if natural compounds remain intact, saturating a beverage with sugar, half-and-half, syrups, or whipped cream transforms it into a dessert, neutralizing any potential health perks.

About the Author

Nancy Oliveira, MS, RD, LDN, CDCES, Contributor

Nancy Oliveira is manager of the nutrition and wellness service at Brigham and Women’s Hospital in Boston. In addition, she is the primary science writer at The Nutrition Source website from the Harvard T.H. Chan School … See Full Bio View all posts by Nancy Oliveira, MS, RD, LDN, CDCES

Your face plays an outsized role in your interactions with the world. It’s usually the first thing a person notices when they look at you. It’s home to the eyes, nose, and mouth, vital body parts that allow you to eat, drink, and communicate. But our facial features are also engineered for their own self-protection — and help protect our bodies in many surprising ways.

My brief career as a cowpoke

I learned how the human face is designed for self-protection while whipping around a lasso I’d been given as a birthday gift. At 8, I’d seen enough cowboy movies to think I knew how use it, at least until the rope struck me across my face. Within seconds a raised red streak ran across my forehead, eyebrow, and cheek. But it skipped my eye.

Once sure I was okay, my mom pointed out that being set back and surrounded by my eye socket bones had protected my eye from damage.

I learned two important lessons that day. First, facial anatomy is remarkably good at protecting itself. Second, using a lasso is harder than it looks.

How do your eyes help protect your body?

Our eyes help keep us safe by feeding detailed information about our surroundings to the brain. Having two eyes pointing ahead (rather than just one) allows for depth perception and a wider field of vision.

What’s more:

• Eyebrows help guide debris, sweat, rainwater, or other substances that find their way onto your forehead away from your eyes. They also communicate emotions, as is obvious if you compare the positions of a person’s eyebrows when they are angry, surprised, or fearful.
• Eyelashes act as guards at the front of the eyes, preventing dust, sweat, and other irritants from making it into the eye. And because lashes are sensitive to touch, they can also provide an alert when something is near the eye.
• The cornea protects your eyes from what may be harmful in the environment while allowing light to pass through to reach nerves at the back of the eye. The cornea is perfectly suited for these tasks: its tough outer coating shields the front of the eye, but is clear so that light can pass through it.

How does your nose help protect your body?

The nose that allows us to smell flowers, bread baking, and other pleasant scents also serves as an alarm system: if there’s a gas leak or if food has spoiled, a good sense of smell can be lifesaving. It also warms and humidifies air passing through. That’s important because cold, dry air can be irritating to the lungs.

Additionally:

• Nose hairs help filter larger particles, such as dust or soot, from the air.
• The nasal liningteams with immune cells ready to attack toxic particles from the air, viruses, or other intruders. It also produces protective mucus that can trap small particles and keep nasal passages from drying out.
• Sneezing expels small particles, such as microorganisms or chemical irritants, out through the nose.

How does your mouth help protect your body?

Eating, drinking, and speaking are among the most important functions of the mouth, but there are other ways it’s protective:

• A tight seal forms when you close your mouth. That’s helpful, because otherwise we’d have a hard time swimming — or even just walking around — and might be constantly swallowing bugs (among other challenges)
• Coughing allows you to expel unwanted particles or organisms through your mouth.
• Saliva contains antibodies to attack infectious organisms before these travel further into the body.
• The mucous membranes that line the inside of the mouth allow for the sensation of taste. That’s important for quality of life, and for avoiding eating something toxic. And the mucous membranes host key immune cells, serving as a first-line immune barrier against viruses and other infectious organisms.

The evolution of the human face

How is it that the human face developed to protect its host in so many ways?

As is so often the case with the human body, you can thank evolution. Over thousands of years, evolutionary pressure ensured that features favoring survival were preserved in our genetic makeup.

This includes facial anatomy: each element of your face is there for a reason, from its shape, form and function to its various attachments and orifices. Even features that humans consider attractive (such as symmetry, youthfulness, or familiarity) are partly due to evolutionary pressure: these features help attract mates, and therefore may increase the chances of passing on genes to offspring.

The bottom line

Remarkable features of the human face serve to protect itself and its host. Unlike communication and social interactivity, these features are less well known and probably underappreciated.

So, the next time you look at yourself in the mirror, go ahead: Check how good you look. Or for signs of aging. Or for lettuce in your teeth. But whatever you’re searching for, remember: there’s a lot more to the appearance of your face than how you look.

About the Author

Robert H. Shmerling, MD, Senior Faculty Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing

Dr. Robert H. Shmerling is the former clinical chief of the division of rheumatology at Beth Israel Deaconess Medical Center (BIDMC), and is a current member of the corresponding faculty in medicine at Harvard Medical School. … See Full Bio View all posts by Robert H. Shmerling, MD