How much non-infectious are the "non-infectious" lepromatous leprosy patients?

Nose forms an important site at which the M. leprae in lepromatous leprosy (LL) patients lodge and multiply. Nose forms an important reservoir for M. leprae, from where they may be transmitted to healthy contacts. Inspite of realizing the above fact, nose does not normally receive due importance during the chemotherapy of leprosy. LL patients, after regular treatment with dapsone or rifampin for about 20 wks and 3 wks respectively are normally considered non-infectious. From the present investigation it is clear that local treatment of the ones with a bactericidal agent should perhaps be necessary during chemotherapy of LL patients to make them non-infectious and to control the transmission of the disease.