Mapping and modelling the impact of mass drug adminstration on filariasis prevalence in Myanmar

• Main Authors: Ni Ni Aye, Zaw Lin, Khin Nan Lon, Nay Yi Yi Linn, Thet Wai Nwe, Khin Mon Mon, Kapa Ramaiah, Hannah Betts, Louise A. Kelly-Hope
• Format: Article
• Language: English
• Published: BMC 2018-05-01
• Series: Infectious Diseases of Poverty
• Subjects: Lymphatic filariasis; Elephantiasis; Wuchereria bancrofti; Neglected tropical diseases; Mass drug administration; Transmission assessment surveys
• Online Access: http://link.springer.com/article/10.1186/s40249-018-0420-9

Abstract Background Lymphatic filariasis (LF) is endemic in Myanmar and targeted for elimination. To highlight the National Programme to Eliminate Lymphatic Filariasis (NPELF) progress between 2000 and 2014, this paper describes the geographical distribution of LF, the scale-up and impact of mass drug administration (MDA) implementation, and the first evidence of the decline in transmission in five districts. Methods The LF distribution was determined by mapping historical and baseline prevalence data collected by NPELF. Data on the MDA implementation, reported coverage rates and sentinel site surveillance were summarized. A statistical model was developed from the available prevalence data to predict prevalence at township level by year of measurement. Transmission assessment survey (TAS) methods, measuring antigenemia (Ag) prevalence in children, were used to determine whether prevalence was below a level where recrudescence is unlikely to occur. Results The highest baseline LF prevalence was found in the Central Valley region. The MDA implementation activities scaled up to cover 45 districts, representing the majority of the endemic population, with drug coverage rates ranging from 60.0% to 98.5%. Challenges related to drug supply and local conflict were reported, and interrupted MDA in some districts. Overall, significant reductions in LF prevalence were found, especially after the first 2 to 3 rounds of MDA, which was supported by the corresponding model. The TAS activities in five districts found only two Ag positive children, resulting in all districts passing the critical threshold. Conclusion Overall, the Myanmar NPELF has made positive steps forward in the elimination of LF despite several challenges, however, it needs to maintain momentum, drawing on international stakeholder support, to aim towards the national and global goals of elimination.