Neglected tropical diseases

Lymphatic filariasis: 538 million people treated in 2011 alone

17 September 2012 | Geneva

World Health Organization (WHO) data show that 538 million people received treatment to prevent transmission of lymphatic filariasis (LF) around the world in 2011 alone.

Mass drug administration (MDA) aimed at eliminating LF, spearheaded by WHO’s Global Programme to Eliminate Lymphatic Filariasis continues to achieve unparalleled success since its official inauguration in 2000.

The highest increase in the number of people treated was in the South-East Asia Region, where slightly more than 414 million were treated, compared with just over 380 million in 2010.

Almost 4 billion doses of medicines for the treatment of LF have been delivered for the period 2000 – 2011 to a cumulative targeted population of 952 million people.

A total of 73 countries are endemic for LF.

Figures published in the latest edition of the Weekly Epidemiological Report show that 53 countries are currently implementing mass drug administration, including 12 which have moved to a post-MDA surveillance phase.

At the end of 2011, 59 countries completed mapping of endemic foci. Mapping is continuing in 13 countries, with only one country yet to start.

Snapshot of LF situation in WHO regions

African Region

LF is endemic in 34 of the 47 countries of the region. Out of these, 11 are in the process of mapping endemic foci (Eritrea yet to start).
MDA is being implemented in 19 countries.
Out of a targeted population of 124.9 million in 2011, 94.2 million were treated, representing 11.7 million more than in 2010 (Madagascar, Nigeria and Senegal have yet to report).

Region of the Americas

10.2 million people were targeted for treatment in 2011.
9 million were treated.
There are active foci in Brazil, Guyana, Haiti and the Dominican Republic with 12.4 million people requiring MDA. Haiti accounts for the highest proportion.

Eastern Mediterranean Region

LF is endemic in Egypt, Sudan, South Sudan and Yemen.
Egypt and Yemen provided MDA to 500 000 people, with both countries having implemented 8 rounds, reaching 65% coverage and 1% microfilaraemia prevalence, which now requires a Transmission Assessment Survey.

South-East Asia Region

9 countries are endemic and about 63% of the global population requiring MDA for LF lives in this region.
In 2011, just over 570 million people were targeted. Slightly over 414 million were treated, which represented an increase of 33.7 million between 2010 and 2011.
Western Pacific region (Mekong-Plus)
Of the 33 million people targeted for MDA in this sub-region, 20 million were treated in 2011.