Situation and trends
Progress has been made in mapping the distribution of lymphatic filariasis during the past decade. Altogether 72/73 endemic countries have initiated mapping the distribution of the disease. Globally, 1 403 million people live in the countries where preventive treatment for lymphatic filariasis is required. WHO's African and South-East Asia regions harbour 95% of the population living in endemic areas, and 98% of the infected population. Of the total population requiring preventive chemotherapy for lymphatic filariasis, 866 million (62%) live in the South-East Asia Region (9 endemic countries) and 464 million (33%) live in the African Region (34 countries). The Region of the Americas, Eastern Mediterranean Region and Western Pacific Region (with 4, 4 and 22 endemic countries, respectively) together account for 5% of global distribution. Due to the tremendous efforts of national programmes, more than 4.4 billion treatments have been delivered worldwide since the Global Programme to Eliminate Lymphatic Filariasis (GPELF) was launched in 2000. By the end of 2012, 56 of 73 endemic countries had implemented Mass Drug Administration (MDA). Thirteen of those countries have achieved the targets for interrupting transmission and have stopped MDA.