Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jun 26;19(6):e0013165.
doi: 10.1371/journal.pntd.0013165. eCollection 2025 Jun.

Examining the overlap in lymphatic filariasis prevalence and malaria insecticide-treated net access-use in endemic Africa

Joanna L Whisnant  1 , Mustafa Kamal Sikder  2 , Gizachew Taddesse Akalu  3   4 , Tsegaye Alemu  5   6 , Mubarek Yesse Ashemo  7   8 , Amelia Bertozzi-Villa  9 , Annie J Browne  10 , Ewerton Cousin  1   11 , Paulina Agnieszka Dzianach  12 , Yalemzewod Assefa Gelaw  13   14 , Peter W Gething  15   12 , Taren M Gorman  1 , Simon I Hay  1   11 , Olayinka Stephen Ilesanmi  16   17 , Cathleen Keller  1 , Juniper Boroka Kiss  18 , Jailos Lubinda  19 , Michael A McPhail  18 , Olivia D Nesbit  1 , Gideon Olamilekan Oluwatunase  20   21 , Verner N Orish  22   23 , Amel Ouyahia  24   25 , Susan Fred Rumisha  18   26 , Adam Saddler  19 , Afeez Abolarinwa Salami  27   28 , Francesca Sanna  12 , Desalegn Shiferaw  29   30 , Jacques Lukenze Tamuzi  31   32 , Daniel J Weiss  33   12 , Naod Gebrekrstos Zeru  34   35 , Francis Zeukeng  36   37 , Stephanie R M Zimsen  1 , Jonathan F Mosser  1   11
Affiliations

Examining the overlap in lymphatic filariasis prevalence and malaria insecticide-treated net access-use in endemic Africa

Joanna L Whisnant et al. PLoS Negl Trop Dis. .

Abstract

Eradication and elimination strategies for lymphatic filariasis (LF) primarily rely on multiple rounds of annual mass drug administration (MDA), but also may benefit from vector control interventions conducted by malaria vector control programs. We aim to examine the overlap in LF prevalence and malaria vector control to identify potential gaps in program coverage. We used previously published geospatial estimates of LF prevalence from the Institute for Health Metrics and Evaluation, as well as publicly available insecticide-treated net (ITN) access (proportion of the total population with access to ITNs) and use (proportion of the total population that slept under an ITN) estimates among the total population and malaria Plasmodium falciparum parasite rates (PfPR) from the Malaria Atlas Project (MAP). We aggregated the 5x5 km2 estimates of LF prevalence estimates and ITN estimates to the implementation unit (IU) level using fractional aggregation, for 33 LF and malaria-endemic locations in Africa, and then overlaid the IU-level aggregates. In this analysis, ITN coverage was low in areas where LF is common, with 51.7% (90/174) of high-LF-prevalence-IUs having both access and use estimates under 40%. Most (67.8%; 61/90) of these low-ITN-coverage, high-LF-prevalence locations were also categorized as high- or highest-prevalence for malaria by PfPR, suggesting suboptimal ITN coverage even in some malaria-co-endemic locations. Even in IUs with high LF prevalence but low malaria prevalence, almost half (48.2%; 39/81) had high levels of access to ITNs. When accounting for population, however, gaps in ITN access in such areas were evident: more individuals lived in high-LF, low-malaria IUs with low ITN access (8.68 million) than lived in high-LF, low-malaria IUs with high ITN access (6.76 million). These results suggest that relying on current malaria vector control programs alone may not provide sufficient ITN coverage for high LF prevalence areas. Opportunities for coordinated vector control programs in places where LF and malaria prevalence are high but ITN coverage is low - or additional ITN distribution in high-LF, low-malaria locations - should be explored to help achieve elimination goals.

PubMed Disclaimer

Conflict of interest statement

I have read the journal's policy and the authors of this manuscript have the following competing interests: EC reports payment or honoraria for lectures, presentations, speakers, bureaus, manuscript writing or educational events from the Royal Holloway University of London, and support for attending meetings and/or travel from the Bill and Melinda Gates Foundation; outside the submitted work. JFM reports grant funding from Gavi and support for attending meetings and/or travel from Bill and Melinda Gates Foundation; outside the submitted work.

Figures

Fig 1
Fig 1. Overlay map of LF prevalence (counts; 2018) and ITN access among the total population (%; 2020).
The bivariate choropleth map and scatter plot color key in the center show the degree to which LF prevalence (vertical axis, white to red) and ITN access (horizontal axis, white to blue) overlap. Grey indicates areas considered to be non-endemic. LF: lymphatic filariasis; ITN: insecticide-treated net. Map base layer shapefile is from ESPEN, available from: https://espen.afro.who.int/tools-resources/data-query-tools/cartography-database [18].
Fig 2
Fig 2. Overlay map of LF prevalence (counts; 2018) and ITN use among the total population (%; 2020).
The bivariate choropleth map and scatter plot color key indicate the degree to which LF prevalence (vertical axis, white to red) and ITN use (horizontal axis, white to blue) overlap. Grey indicates areas considered to be non-endemic. LF: lymphatic filariasis; ITN: insecticide-treated net. Map base layer shapefile is from ESPEN, available from: https://espen.afro.who.int/tools-resources/data-query-tools/cartography-database [18].
Fig 3
Fig 3. Overlay map and scatter plot of LF prevalence by (%; 2018) and ITN access among the total population (%; 2020).
The bivariate choropleth map and scatter plot color key in the center indicate the degree to which LF prevalence (vertical axis, white to red) and ITN access (horizontal axis, white to blue) overlap. Grey indicates areas considered to be non-endemic. LF: lymphatic filariasis; ITN: insecticide-treated net. Map base layer shapefile is from ESPEN, available from: https://espen.afro.who.int/tools-resources/data-query-tools/cartography-database [18].
Fig 4
Fig 4. Overlay map of LF prevalence (%; 2018) and ITN use among the total population (%; 2020).
The bivariate choropleth map and scatter plot color key in the center indicate the degree to which LF prevalence (vertical axis, white to red) and ITN use (horizontal axis, white to blue) overlap. Grey indicates areas considered to be non-endemic. LF: lymphatic filariasis; ITN: insecticide-treated net. Map base layer shapefile is from ESPEN, available from: https://espen.afro.who.int/tools-resources/data-query-tools/cartography-database [18].
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. World Health Organization. Global programme to eliminate lymphatic filariasis: progress report, 2021 [Internet]. WHO; 2022. [cited 2023 Sep 14]. Available from: https://www.who.int/publications/i/item/who-wer9741-513-524
    1. World Health Organization. Ending the neglect to attain the Sustainable Development Goals: A road map for neglected tropical diseases 2021–2030 [Internet]. WHO; 2021. [cited 2023 Sep 14]. Available from: https://www.who.int/publications/i/item/9789240010352
    1. United Nations Department of Economic and Social Affairs. The Sustainable Development Goals Report 2023: Special Edition [Internet]. United Nations; 2023. Jul [cited 2023 Sep 18]. Available from: https://www.un-ilibrary.org/content/books/9789210024914
    1. World Health Organization. Lymphatic filariasis. [cited 2023 September 18]. Available from: https://www.who.int/news-room/fact-sheets/detail/lymphatic-filariasis
    1. Vos T, Lim SS, Abbafati C, Abbas KM, Abbasi M, Abbasifard M, et al. Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019. The Lancet. 2020;396(10258):1204–22. - PMC - PubMed

MeSH terms