Don’t look now but leprosy is back.
This week in Manila, Philippines dozens of academics, health care professionals and leprosy stakeholders are gathering to discuss a phenomenon that’s leaving many medical observers spooked. Leprosy, one of the oldest of infectious human diseases, was supposed to have been vanquished by modern medicine.
But it never really went away – not completely.
And now cases are popping up everywhere, including in major metropolises like Los Angeles.
Some scientists are warning that leprosy could become America’s “next public health crisis.” It’s scary.
According to the Centers for Disease Control, there are more than 200,000 new cases of leprosy reported in the world annually. Nearly two-thirds of them are found in India, which is home to one-third of the world’s poor.
The poor are disproportionately affected by leprosy. Poor sanitation, overcrowded living conditions and a lack of prompt diagnosis and treatment can “easily convert a disease that should be rare into one that is more common,” the Hill newspaper reported last week.
In the United States, between 150 and 200 new cases of leprosy — also known as “Hansen’s Disease” — are being reported every year. Most occur in deep southern states like Louisiana, Alabama, Florida, and Texas.
But there is evidence that heavy concentrations of the poor, especially homeless populations in urban centers further north are becoming highly susceptible to spreading the disease.
One factor may be immigration. Mexico and Central America have a much higher number of leprosy cases – some 20,000 annually — and immigrants from those regions may be carrying the disease when they cross the border into the interior.
A recent study by the Keck Medical Center at the University of Southern California examined 187 leprosy patients treated at its clinic from 1973 to 2018. The Center found that most of their patients were poor Hispanics who had emigrated from Mexico.
A leprosy “scare” would seem overblown because the disease, once detected, is easily treated with antibiotics.
But public health officials warn that concentrations of poor minorities, especially difficult-to-reach homeless populations, may not get the treatment they need before the disease becomes more contagious — and dangerous.
Some doctors fear that a leprosy outbreak could spread rapidly among the estimated 60,000 homeless in Los Angeles County, and become a minor epidemic before health authorities could take remedial action.
Part of the problem with leprosy is that it can take 5 years or more (in some cases, 10) for the disease to become apparent, often through the spread of sores and a loss of sensation in the extremities, followed by more severe deformities and even blindness if left untreated.
In the Keck Center study, 26% of the patients had a “visible deformity,” a sign that their leprosy had progressed substantially.
Some observers think the leprosy “threat” is overblown. Given the relatively small number of annual cases, a public panic is unwarranted – and counter-productive. Fighting the “stigma” of leprosy is essential if at-risk populations are to be located and treated, they say.
But anecdotal evidence suggests that the number of cases is growing. There were nearly two dozen cases in Texas alone in 2017. Other states like Florida have reported a slight decline over the past three years. But leprosy infections that have yet to manifest could be spreading under the radar.
Despite dating back to the medieval era, surprisingly little is known about what actually causes leprosy. The disease is thought to be transmitted through nose droplets and saliva via coughing and sneezing but close sustained contact with a leprosy sufferer is required to become infected.
There is also evidence that animals like armadillos are a major source of leprosy contagion. Armadillos can store the disease in their fat and transmit it when humans come in close contact with them, which is common in Mexico and states like Texas.
Even spending prolonged time in an area inhabited by armadillos can increase your risk of the disease, experts say. In South Florida, a NASA scientist became infected in 2018 when he conducted fieldwork in an area with a heavy concentration of the animals.
Several other cases of leprosy in Florida have been blamed on contact with armadillos, which are known to spit at other animals (including humans) as a precautionary measure.
In Los Angeles and other metropolitan areas, federally supported “ambulatory clinics” are beginning to focus on leprosy, with special efforts made to reach the homeless where the risk is considered greatest.
There is also a major push to develop a leprosy-specific vaccine, thanks largely to advocacy efforts by the American Leprosy Missions. Work on the vaccine, which has reached clinical trials phase 1 stage, is being conducted at the Infectious Disease Research Institute, with support from the Novartis Foundation.
Experts say that leprosy is just one of a number of infectious diseases that are beginning to make a comeback. Another is typhus, which is carried by fleas that feed on rats that rummage through garbage and sewage.
In 2018 there were 20 cases of typhus in Pasadena, CA alone — four times the number that typically occurs there in a single year. Nine cases of typhus outbreak were also reported in Los Angeles last summer, leading to fears of a possible epidemic.