Partnering for impact: Integrated transmission assessment surveys for lymphatic filariasis, soil transmitted helminths and malaria in Haiti

Abstract

BackgroundSince 2001, Haiti’s National Program for the Elimination of Lymphatic Filariasis (NPELF) has worked to reduce the transmission of lymphatic filariasis (LF) through annual mass drug administration (MDA) with diethylcarbamazine and albendazole. The NPELF reached full national coverage with MDA for LF in 2012, and by 2014, a total of 14 evaluation units (48 communes) had met WHO eligibility criteria to conduct LF transmission assessment surveys (TAS) to determine whether prevalence had been reduced to below a threshold, such that transmission is assumed to be no longer sustainable. Haiti is also endemic for malaria and many communities suffer a high burden of soil transmitted helminths (STH). Heeding the call from WHO for integration of neglected tropical diseases (NTD) activities, Haiti’s NPELF worked with the national malaria control program (NMCP) and with partners to develop an integrated TAS (LF-STH-malaria) to include assessments for malaria and STH.Methodology/Principle findingsThe aim of this study was to evaluate the feasibility of using TAS surveys for LF as a platform to collect information about STH and malaria. Between November 2014 and June 2015, TAS were conducted in 14 evaluation units (EUs) including 1 TAS (LF-only), 1 TAS-STH-malaria, and 12 TAS-malaria, with a total of 16,655 children tested for LF, 14,795 tested for malaria, and 298 tested for STH. In all, 12 of the 14 EUs passed the LF TAS, allowing the program to stop MDA for LF in 44 communes. The EU where children were also tested for STH will require annual school-based treatment with albendazole to maintain reduced STH levels. Finally, only 12 of 14,795 children tested positive for malaria by RDT in 38 communes.Conclusions/SignificanceHaiti’s 2014–2015 Integrated TAS surveys provide evidence of the feasibility of using the LF TAS as a platform for integration of assessments for STH and or malaria.

Haiti’s Commitment to Malaria Elimination: Progress in the Face of Challenges, 2010–2016

“…Since 2014, the PNCM has been able to take advantage of the ongoing LF TAS in 21 of 23 total evaluation areas in the country to obtain information on malaria transmission by conducting an integrated TAS. 41 Preliminary results from one evaluation area, the Department of Nippes, that incorporated malaria testing into the LF TAS, found zero children who were positive by RDT. However, serology results from the same children showed that those in 34 of the 43 schools had evidence for previous exposure to malaria by the presence of antibodies against P. falciparum (PNCM data/Rogier E, personal communication).…”

Combination of Serological, Antigen Detection, and DNA Data for Plasmodium falciparum Provides Robust Geospatial Estimates for Malaria Transmission in Haiti

“…Human subjects. Samples were collected in Haiti in May 2015 from the Saut d'Eau commune and in April 2016 from the Grand Anse department as part of a lymphatic filariasis (LF) transmission assessment survey 27 , with integration of malaria RDTs and soil-transmitted helminth microscopy of stool specimens 43 . Before enrollment, informed consent forms were sent home with each of the students so parent or legal guardian could read and sign for return to the study teams.…”

“…Using the tables provided by WHO 44 , the target sample size and the critical cut-off threshold was determined and if the number of positive children identified fell below the critical cut-off threshold, the recommendation was made to stop mass-drug administration (MDA) for LF. Upon completion of MDA, TAS surveys were conducted to determine whether populations have reached the critical threshold of infection prevalence (<2% antigenemia), below which LF transmission is likely no longer sustainable 43 .…”

A first nation-wide assessment of soil-transmitted helminthiasis in Fijian primary schools, and factors associated with the infection, using a lymphatic filariasis transmission assessment survey as surveillance platform

“…countries [24][25][26]. This experience led to the recommendation in the WHO guidelines to assess the epidemiology of STH during LF-TAS [2]: the target population for the STH survey in conjunction with LF-TAS is designated as 8-10-year-olds for school-based surveys and 6-7-year-olds for household surveys.…”