Leprosy in Florida – What We Know Now
Leprosy is often thought of as a medical ailment of the past and a disease that doesn’t affect the modern world. But, in the past several years, health care providers have seen an uptick in leprosy diagnoses across the U.S., with a concentration of newly-diagnosed patients in Central Florida.
While the source of these new cases is unknown, armadillos may be the culprit. Scientists are working to understand how this infectious disease continues to spread from person to person across the globe and why Central Florida has been greatly affected.
What is the risk of leprosy today?
According to the Centers for Disease Control and Prevention (CDC), the risk of adults getting leprosy (also known as Hansen disease) is low because more than 95% of all people have natural immunity.
The number of leprosy cases worldwide varies yearly, and it remains an uncommon disease. In the U.S., the count reached 216 in 2019, then dropped to 159 in 2020. The recent uptick in Florida is not a public health crisis; travel warnings have not been issued for the state, but the disease is considered endemic in Central Florida.
How does someone develop leprosy?
Scientists think that the bacteria that cause this infectious disease (mycobacterium leprae) are transmitted through droplets from the nose and mouth when someone with Hansen disease coughs or sneezes near a healthy person (similar to how COVID-19 spreads from person to person). According to the CDC, prolonged, close contact over many months with someone with untreated leprosy is needed to catch the disease.
You cannot get leprosy from sexual or casual contact, including hugging, shaking hands, sitting next to an infected person, or eating at the same table. Hansen disease does not pass from infected mothers to their babies during pregnancy.
What’s causing leprosy cases in Florida?
In the southern U.S., where most newly diagnosed cases occur, some armadillos carry the bacteria that cause Hansen disease. The CDC says the risk of transmission from armadillos to people is generally low. But, it’s possible that the recent increase in leprosy cases in Florida originated with human contact with these animals and then spread from infected people to others.
Since 2019, the World Health Organization (WHO) has reported cases of leprosy in other countries with tropical climates, with the highest numbers in Southeast Asia. Affected countries include the Democratic Republic of Congo, Ethiopia, Madagascar, Mozambique, Nigeria, the United Republic of Tanzania, Bangladesh, India, Indonesia, Myanmar, Nepal, Philippines, Sri Lanka and Brazil. Each of these countries has reported 1,000 to 10,000 new cases. Travel to these areas or prolonged contact with infected people from these regions may have contributed to the recent cases in the U.S.
What are the symptoms of leprosy?
After someone has come in contact with the bacteria that cause leprosy, it takes three to five years (up to 20 years) for symptoms of the disease to appear. This makes it difficult to determine when and how an infected person came in contact with the bacteria.
Hansen disease affects the skin, peripheral nerves, mucosa of the upper respiratory tract and the eye because mycobacterium leprae prefers cooler body parts. Over months or years, the infection can progress to permanent disabilities. The CDC says approximately two million people worldwide are permanently disabled as a result of Hansen disease.
Leprosy skin symptoms:
- Light-colored skin patches, usually flat, with or without numbness
- Skin growths called nodules
- Different textured skin (thick, stiff or dry)
- Painless ulcers on the soles of feet or on the fingers (attributed to nerve damage and loss of pain sensation)
- Painless swelling or lumps on the face or earlobes
- Hair loss on eyebrows and/or eyelashes
Signs of nerve damage caused by leprosy:
- Skin numbness
- Muscle weakness or paralysis (especially in the hands and feet)
- Enlarged nerves (especially those around the elbow, knee and the side of the neck)
- Eye problems (caused by damaged facial nerves)
When the disease affects the mucosal membranes, patients can experience stuffy noses and nosebleeds.
How is leprosy diagnosed?
Doctors can diagnose leprosy with a skin examination and a biopsy called a slit-skin smear, checking for the following signs of the disease:
- pale or reddish skin patches with loss of sensation
- loss of sensation and/or weakness of muscles that are connected to a thickened or enlarged peripheral nerve
- painless nodules on the face or earlobes
- rod-shaped bacteria (called bacilli) seen with a microscope in fluid from a cut in involved skin
Is there a cure for leprosy?
Yes, leprosy is curable with multidrug therapy.
People diagnosed with leprosy generally receive a combination of three drugs: dapsone, rifampicin and clofazimine. These drugs take 6 to 12 months, depending on the specific disease type, to kill the bacteria and cure the patient. Treatment in the early stages of infection can prevent disability.
The spread of mycobacterium leprae from one person to another happens infrequently, and the risk of transmission stops when the infected person begins treatment.
To help prevent the spread of leprosy to others, the WHO recommends that family and friends who cannot avoid prolonged close contact with someone diagnosed with leprosy receive a single dose of rifampicin as preventive chemotherapy.
With the Global Leprosy Strategy 2021–2030, the WHO is striving to eradicate leprosy worldwide.
Dana Kantrowitz is a contributing writer for UHealth’s news service.