Yes, leprosy is still very much around. In 2024, 188 countries reported a combined 172,717 new cases to the World Health Organization. While that number is a fraction of what it was decades ago, leprosy remains a significant public health challenge in parts of Asia, Africa, and South America. It even shows up in the United States, where roughly 200 new cases are diagnosed each year.
Where Leprosy Still Occurs
Leprosy is concentrated in tropical and subtropical regions. India, Brazil, and Indonesia consistently report the highest numbers of new cases. But the disease isn’t confined to those countries. Cases appear across Southeast Asia, sub-Saharan Africa, and parts of the Pacific Islands. Even in the U.S., about a third of patients have no history of foreign travel and no known contact with an infected person, which means they likely picked up the bacteria domestically.
In the southeastern United States, nine-banded armadillos are a known carrier. These animals are highly susceptible to the bacteria and can harbor enormous quantities of it in their tissues. Contact with armadillos, whether through hunting, handling, or simply living in areas where they’re common, is a documented route of infection. The geographic range of this animal-to-human transmission appears to be expanding.
How It Spreads
Leprosy spreads through respiratory droplets from the nose and mouth of someone with an untreated infection. The key word is “prolonged.” You cannot catch leprosy from shaking hands, hugging, sharing a meal, or sitting next to someone who has it. Transmission requires close, sustained contact over time, which is one reason the disease moves slowly through populations.
The bacteria behind leprosy reproduces extremely slowly compared to most infectious organisms. The incubation period averages about five years, but symptoms can take as long as 20 years to appear. That long delay makes it difficult to trace exactly when or where someone was infected.
What It Looks Like
The earliest signs are usually skin patches that look different from the surrounding skin. They may be lighter, reddish, or copper-colored, and they can be flat, raised, or nodular. A hallmark feature is that these patches often lose sensation. You might not feel a light touch, heat, or pain in the affected area. That numbness is the result of the bacteria targeting nerve cells.
The bacterium has an unusual preference for the protective cells that wrap around peripheral nerves. Once inside these cells, it triggers inflammation that strips away the insulating layer around nerve fibers. The nerves most commonly affected run through the arms, hands, legs, and feet. Over time, this damage causes muscle weakness, loss of fine motor control, and a dangerous inability to feel injuries. People with advanced, untreated leprosy can burn, cut, or otherwise injure themselves without realizing it, leading to secondary infections and, eventually, permanent disfigurement. That progression is what gave the disease its fearsome historical reputation.
Leprosy Is Curable
Leprosy has been fully curable since the 1980s with a combination of three antibiotics. Milder cases require six months of treatment. More severe cases take 12 months. Once treatment begins, a person quickly becomes non-infectious, and the bacteria are steadily eliminated from the body. The treatment is provided free of charge worldwide through a WHO-coordinated program.
The catch is timing. Antibiotics kill the bacteria, but they cannot reverse nerve damage that has already occurred. Early detection is the difference between a complete recovery and lasting disability. That’s why global health organizations focus heavily on finding cases before nerve involvement becomes severe.
Why It Hasn’t Been Eliminated
Given that a cure exists and has been widely available for decades, you might wonder why leprosy persists at all. Several factors keep it circulating. The extraordinarily long incubation period means people can carry and transmit the bacteria for years before anyone knows they’re infected. Poverty, limited healthcare access, and the stigma still attached to a leprosy diagnosis discourage people from seeking care early. And in some regions, the animal reservoir (armadillos in the Americas, possibly other species elsewhere) provides a source of infection that can’t be addressed through human treatment alone.
The WHO’s current global strategy aims for 120 countries to report zero locally acquired cases, a 70% reduction in new cases overall, and a 90% reduction in cases involving serious disability, all by 2030. Progress has been steady over the past few decades, but the pace has slowed. Annual case numbers have plateaued rather than continuing to decline, suggesting that the remaining burden is the hardest to reach.
The Stigma Problem
Leprosy carries a social burden that most other curable diseases do not. Centuries of fear and misunderstanding branded it as a punishment or a mark of uncleanliness, and that stigma persists in many communities today. People may hide symptoms, avoid clinics, or face discrimination in housing and employment even after being cured. In some countries, outdated laws still permit the forced isolation of people with leprosy or restrict their civil rights.
This stigma is medically unjustified. Leprosy is one of the least contagious infectious diseases. Roughly 95% of the human population has a natural immune resistance to the bacteria and will never develop the disease even if exposed. For those who are susceptible, early treatment eliminates the risk of disability and stops transmission. The gap between the science and the public perception remains one of the biggest obstacles to eliminating leprosy for good.