A new report in the Centers for Disease Control and Prevention’s medical journal looked at an increase in leprosy cases in 2020 in states like Florida, and the increase in “locally acquired” infections has left researchers searching for answers regarding how the rare millennia-old disease is spreading.

Key Facts

The study looked at a leprosy case in a 54-year-old Florida man after researchers couldn’t pinpoint the source of his disease: He hadn’t traveled domestically or internationally, had any prolonged contact with immigrants from leprosy-endemic countries, known anyone with leprosy or had any exposure to armadillos, who carry the disease.

Leprosy is still rare in the U.S., but researchers say the presence of cases without clear causes may suggest the disease has become endemic—the constant presence of a somewhat controlled disease in a community that’s easily treatable and preventable—in the southeast.

According to the report, leprosy cases in the southeastern U.S. rose in 2020, with Florida accounting for the majority of cases, leading the researchers to recommend doctors test patients who’ve traveled from Florida for leprosy.

Though national cases dropped from 173 to 159 from 2011 to 2020, cases in the southeast “more than doubled” over the last decade, according to the study.

Central Florida saw the most uptick in cases, making up 81% of all cases in Florida and one-fifth of all cases across the country.Other states that account for a combined 69% of new leprosy cases are Texas, Hawaii, California, New York and Louisiana, according to U.S. Department of Health and Human Services data.

Though about 66% of cases are from people who immigrated from leprosy endemic countries, about 34% were locally acquired, a concerning number because the cause is unknown, the study said—there’s “no clear evidence” of animal transmission or other “traditionally known risk factors.”

Key Background

Leprosy, also known as Hansen’s disease or the “biblical disease,” is caused by a bacteria called Mycobacterium leprae, which can affect the skin, upper respiratory tract, eyes and mucosa, causing physical deformities. Leprosy is not an easy disease to catch, with scientists discovering that it takes months of close contact with a person with leprosy in order to get it. According to the American Academy of Dermatology, it’s typically spread via person-to-person contact, when droplets containing the bacteria are passed from coughs or sneezes. So, a handshake or a lengthy conversation with someone with the disease won’t cause transmission. Leprosy also has zoonotic transmission, with research from Colorado State University finding human contact with wild armadillos in Brazil has caused an increase in cases in the country. The team surveyed Brazilians with the disease and found that 65% had either some contact with armadillos, were involved with the preparation and cooking of armadillo meat or ate armadillo meat at least once a year. Skin symptoms of leprosy include painless ulcers on the feet, nodules on the skin, discolored, numb patches on the skin, stiff, thick or dry skin, loss of eyelashes or eyebrows and painless swelling on the face or earlobes. Mucous membrane symptoms include nosebleeds and stuffy nose and nerve damage symptoms are muscle weakness or paralysis (specifically in the hands or feet), eye problems that can lead to blindness, numbness around affected areas and enlarged nerves, mainly the sides of the neck, elbows and knees.

Surprising Fact

Contrary to popular belief, leprosy is a curable disease. It typically requires multi-drug therapy that includes antibiotics like rifampicin, dapsone and clofazimine, and usually lasts between one and two years. Because treatment lasts for so long, the use of multiple antibiotics is to prevent antibiotic resistance, so it’s especially important for patients to take all antibiotics until their doctor says the treatment is complete to prevent the bacteria from growing again. Early detection is important because if left untreated, leprosy can cause chronic non-healing ulcers on the soles of the feet, blindness, paralysis, nose disfigurement and the shortening of fingers and toes.


Leprosy is known as the “biblical disease” because early Israelites thought illness was a form of punishment, with leprosy being one of the illnesses researchers believe was included, according to a study published in the Journal of The American Academy of Dermatology. Leprosy was seen as both a punishment for sins and a divine curse because there was no cure and it was chronic before modern medicine. These punishment diseases were known as tzaraat, and though some researchers have interpreted this to include leprosy, others are doubtful. According to a study published in the Clinics of Dermatology, tzaraat has “no relation to leprosy” as it’s known in modern times or in the Middle Ages, though a few people may have had the disease. Throughout history, people with leprosy—called “lepers”—were forced to isolate themselves from the general population out of fear of spreading the disease, a study published in InfezMed reports. In Europe, hundreds of lepers had to live in buildings specifically made for leprosy called lazar houses, or they were forced to be homeless. During the Middle Ages, “Leper Masses” were held to celebrate the death of someone with leprosy as they were no longer a threat to society.

2023-07-31T20:01:43Z dg43tfdfdgfd