Treatment The first effective treatment (promin) became available in the 1940s.[116] In the 1950s, dapsone was introduced. The search for further effective antileprosy drugs led to the use of clofazimine and rifampicin in the 1960s and 1970s.[117] Later, Indian scientist Shantaram Yawalkar and his colleagues formulated a combined therapy using rifampicin and dapsone, intended to mitigate bacterial resistance.[118] Multi-drug therapy (MDT) combining all three drugs was first recommended by the WHO in 1981. These three antileprosy drugs are still used in the standard MDT regimens.[119] Leprosy was once believed to be highly contagious and was treated with mercury, as was syphilis, which was first described in 1530. Many early cases thought to be leprosy could actually have been syphilis.[120] Resistance has developed to initial treatment. Until the introduction of MDT in the early 1980s, leprosy could not be diagnosed and treated successfully within the community.[121] Japan still has sanatoriums (although Japan's sanatoriums no longer have active leprosy cases, nor are survivors held in them by law).[122] The importance of the nasal mucosa in the transmission of M leprae was recognized as early as 1898 by Schäffer, in particular, that of the ulcerated mucosa.[123] The mechanism of plantar ulceration in leprosy and its treatment was first described by Dr Ernest W Price.[124]