A communicable disease, chronic in nature, caused by Mycobacterium (M) leprae. It occurs at any age and in a variety of forms. The two major forms are lepromatous and tuberculoid. The usual incubation period is 3 to 5 years, but it can range from 1 to 30 years.

The lepromatous leprosy (LL) form manifests in skin lesions and involvement of peripheral nerves on each side of the body. Partial or complete loss of sensation, muscle weakness, and paralysis occurs. Lesions are limited to the skin, upper respiratory tract, and testes. In polar tuberculoid leprosy (TT), which is usually non-recurrent, the nerve lesions occur on one side of the body, and loss of sensation in the skin occurs early. Organ involvement is not seen.

Symptoms begin gradually. Skin changes are usually the first sign of infection. However, changes may be so vague and slow to develop they may not be recognized for years.

Suspected skin lesions are tested via biopsy to confirm the diagnosis. However, the organisms may not be present in tuberculoid lesions. Lymphocyte transformation test and the leukocyte migration inhibition test are also utilized.

Leprosy management may require consulting an expert. Different forms of sulfur oxidation products are used to treat leprosy, but resistance to these preparations has resulted in the use of the combined chemotherapy treatment of dapsone, rifampin, and clofazimine. After 3 months of dapsone or clofazimine therapy, patients are usually not infectious. With the use of rifampin, it takes 3 days for patients to become non-infectious. Treatment may be complicated by an acute reverse reaction in tuberculoid leprosy resulting in redness of the skin, swelling and possible progression to necrosis and ulceration which require additional medications.

Bacterial skin infections, ulcers, and traumatic amputation of fingers due to loss of sensation are possible. Tuberculosis may be a complication when lepromatous leprosy is untreated. It is not a common complication of the tuberculoid form. Amyloidosis may be the cause of death in advanced cases. However, with early treatment, the chances of recovery are encouraging.

1. Leprosy (Hansen's disease) has a three year presumptive period. This disease shall be granted service connection although not otherwise established as incurred in or aggravated by service if manifested to a compensable degree within the applicable time limit under §3.307 following service in a period of war or following peacetime service on or after January 1, 1947, provided the rebuttable presumption provisions of §3.307 are also satisfied [38 CFR 3.309 [Disease subject to presumptive service connection], §3.309(a) [chronic disease].

2. May be entitled to special monthly compensation where the veteran has a single service-connected disability rated as 100% and/or other requirements/qualifications under 38 CFR §3.350 [Special monthly compensation ratings]. Also reference M21-1MR, Part III, Subpart iv, Chapter 6, Section B, Topic 3 [Inferred Issues & Ancillary Benefits]. 

3. Consider service connection on a presumptive basis as a tropical disease (38 CFR §3.307 and §3.309 (b)).

Continue a 100 percent evaluation beyond the cessation of treatment for active disease. Six months after discontinuance of such treatment, determine the appropriate disability rating by mandatory VA examination. Any change in evaluation based upon that or any subsequent examination shall be subject to the provisions of § 3.105(e) of this chapter. Thereafter, rate under the appropriate body system any residual disability of infection, which includes, but is not limited to, skin lesions, peripheral neuropathy, or amputations. (38 CFR §4.88b [Schedule of ratings-infectious diseases, immune disorders and nutritional deficiencies]).