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Review
. 2023 Oct 9;378(1887):20220280.
doi: 10.1098/rstb.2022.0280. Epub 2023 Aug 21.

Lymphatic filariases and soil-transmitted helminthiases in Sri Lanka: the challenge of eliminating residual pockets of transmission

Nilmini T G A Chandrasena  1 , I E Gunaratna  2 , Dileepa Ediriweera  3 , N R de Silva  4
Affiliations
Review

Lymphatic filariases and soil-transmitted helminthiases in Sri Lanka: the challenge of eliminating residual pockets of transmission

Nilmini T G A Chandrasena et al. Philos Trans R Soc Lond B Biol Sci. .

Abstract

Sri Lanka has successfully met the challenge of controlling both lymphatic filariasis (LF) and soil-transmitted helminthiases (STH) as public health problems. The primary public health strategy for combatting both conditions has been preventive chemotherapy. The national programme for the elimination of LF implemented five annual rounds of mass chemotherapy in the endemic districts from 2002 to 2006 using a combination of diethylcarbamazine and albendazole. The overall microfilaria rate declined from 0.21% in 2001 before the mass chemotherapy, to 0.06% in 2016, at declaration of elimination of LF as a public health problem by the World Health Organization. Currently Sri Lanka is in the phase of post-validation surveillance. Achieving control of STH has been more difficult. Mass deworming programmes have been implemented for nearly a century, and national-level surveys reported prevalence rates declining from 6.9% in 2003 to 1% in 2017. However, neither of these infections has been completely eliminated. A situation analysis indicates continued transmission of both among high-risk communities. This paper explores the reasons for persistence of transmission of both LF and STH in residual pockets and the measures that are required to achieve long-term control, or perhaps even interrupt transmission in Sri Lanka. This article is part of the theme issue 'Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs'.

Keywords: control strategies; elimination as a public health problem; interruption of transmission; lymphatic filariasis; soil-transmitted helminthiasis.

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Conflict of interest statement

We declare that we have no competing interests.

Figures

Figure 1.
Figure 1.
(a) Infected rate of Culex mosquitoes in the eight endemic districts, 2016–2021. Source: AFC Health Bulletin 2016–2021. (b) Infective rate of Culex mosquitoes in the eight endemic districts, 2016–2021. Source: AFC Health Bulletin 2016–2021.
Figure 2.
Figure 2.
Estimated soil-transmitted helminthiasis (STH) prevalence in Sri Lanka (adapted from [30]). Grey lines indicate district boundaries.
Figure 3.
Figure 3.
Occurrence probability of W. bancrofti infections in Sri Lanka (MaxEnt ecological niche modelling). Grey lines indicate district boundaries.
See this image and copyright information in PMC

References

    1. Abdulcader MH, Sasa M. 1966. Epidemiology and control of bancroftian filariasis in Ceylon. Jpn J. Exp. Med. 36, 609-646. - PubMed
    1. Uragoda CG. 1987. A history of medicine in Sri Lanka: from the earliest times to 1948. Colombo, Sri Lanka: Sri Lanka Medical Association.
    1. Lambrecht FL. 1974. Entomological aspects of filariasis control in Sri Lanka. Bull. Wld Health Org. 51, 133-143. - PMC - PubMed
    1. Dissanaike AS. 1961. Filariasis in Ceylon then (1961) and in Sri Lanka now (1990–30 years on). Ann. Trop. Med. Parasitol. 85, 123-129. (10.1080/00034983.1991.11812538) - DOI - PubMed
    1. World Health Organization. 2000. Preparing and implementing a national plan to eliminate lymphatic filariasis (in countries where onchocerciasis is not co-endemic), WHO/CDS/CPP/CEE 200016. Geneva, Switzerland: World Health Organization.

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