ハンセン病の予防投薬についての最近の話題

抄録

  As the number of new leprosy patients per year has been stagnant for the past half decade, multi-drug therapy (MDT) alone is now regarded to be insufficient to stop the transmission of Mycobacterium leprae and to eradicate/eliminate leprosy from the world. New strategies are now being searched. Chemoprophylaxis was one promising strategy used during the 1960s and 1970s as a part of leprosy control. However, due to the introduction and successful outcome of MDT since 1981, it was once forgotten. In addition, the drug of choice for the initial chemoprophylaxis, either dapsone or acedaposone, added to its discontinuation as it required long dosing period of two to three years. It was not only impractical for chemoprophylaxis, but also was associated with risk of resistance development.
  Recently, chemoprophylaxis is again drawing attention; this time with rifampicin. Results from one randomized control trial conducted in Bangladesh prompted this reintroduction of chemoprophylaxis into leprosy control, along with a few other studies. On the other hand, concerns remain for wide implementation of chemoprophylaxis. Could we base our scientific background of the intervention solely to these studies with limited follow-up period, while the incubation period of Mycobacterium leprae is said to be as long as several decades? Furthermore, chemoprophylaxis was less effective in close contacts in these studies. What does this result indicate? How about the risk of resistance development? More importantly, how could rights of the patients be protected if they are asked to disclose their disease? This review summarizes the past and present situation of leprosy chemoprophylaxis along with some discussion.