Mini-TAS as a confirmatory mapping tool for remapping areas with uncertain filarial endemicity to exclude/ include for mass drug administration: A report from field validation in India

Barsa Baisalini Panda; Kaliannagounder Krishnamoorthy; Arundhuti Das; Hitesh Kumar Jain; Sujata Dixit; Manju Rahi; Nilam Somalkar; Shubhashisha Mohanty; Sanghamitra Pati; Manoranjan Ranjit; Madhusmita Bal

doi:10.1371/journal.pone.0293641

Mini-TAS as a confirmatory mapping tool for remapping areas with uncertain filarial endemicity to exclude/ include for mass drug administration: A report from field validation in India

PLoS One. 2023 Nov 3;18(11):e0293641. doi: 10.1371/journal.pone.0293641. eCollection 2023.

Affiliations

¹ Regional Medical Research Centre, Bhubaneswar, Odisha, India.
² ICMR-Vector Control Research Centre, Puducherry, India.
³ Indian Council of Medical Research, New Delhi, India.
⁴ Regional Office for Health & Family Welfare, Bhubaneswar, Odisha, India.
⁵ National Centre for Vector Borne Diseases Control, Bhubaneswar, Odisha, India.

Abstract

India has targeted elimination of lymphatic filariasis (LF) through mass drug administration (MDA) by 2027. Mapping of LF endemic areas is a priority for implementation of MDA. Current national LF remapping tool for unsurveyed/uncertain districts, have many limitations. The WHO has recommended a sensitive and rapid remapping protocol (Mini-TAS), that needs validation in Indian setting. Hence, in the present study a comparative assessment of these two protocols (national protocol vs Mini-TAS) was undertaken in two non-MDA districts of Odisha, with unknown filarial endemicity but reporting chronic cases. Purposive sampling was done in five top sites based on filarial case count as per the national protocol. Random 30 cluster survey was done by conducting school based Mini-TAS, Microfilariae (Mf) survey among adults (>10 years) in villages/wards with schools and Molecular Xenomonitoring (MX) of infection in vectors. Costing by activity and items of the surveys was acomplished using itemized cost menu. In Kalahandi, one of the five purposive sampling sites showed Mf prevalence above threshold (> 1%). But except Mini-TAS neither MX nor house-hold Mf survey among adults could detect the infection above the threshold. While in Balangir, Mf prevalence in all purposive sampling sites,Mini-TAS, Mf prevalence among adult and MX were above the respective thresholds confirming endemicity of LF in the district. The per sample cost of purposive sampling for Mf was the lowest INR 41, followed by adult Mf sampling INR 93. Mini-TAS and MX were expensive with INR 659 and 812 respectively. The study demonstrates that though all the sampling methods could detect filarial infection above the threshold in high-risk areas, Mini-TAS could only detect infection in low-risk areas. Therefore, in the national programme Mini-TAS can be used as a decision-making tool to determine whether to exclude/ include a district having uncertain endemicity for MDA.

Copyright: © 2023 Panda et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Animals
Elephantiasis, Filarial* / drug therapy
Elephantiasis, Filarial* / epidemiology
Humans
India / epidemiology
Mass Drug Administration* / methods
Microfilariae
Prevalence
Surveys and Questionnaires
Wuchereria bancrofti

Grants and funding

1.Grant Received By: MB, MRR, SP 2. Grant Number: No. 6/9-7(248)/2020-ECD-II 3. Indian Council of Medical Research 4.https://main.icmr.nic.in/ 5.The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.