Evidence map›Paper›PMID 40087683›Full record

ArticleMalaria journal2025

Estimating the hole surface area of insecticide-treated nets using image analysis, manual hole counting and exact hole measurements.

Emmanuel Mbuba, Natalia Mañas-Chavernas, Sarah J Moore, Philipo David Ruzige, Dickson Kobe, Jason Moore, Rose Philipo, Noela Kisoka, Gianpaolo Pontiggia, Frank Chacky and 5 more

Abstract read
In one paragraph

Article in Malaria journal, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0cells of the map it votes in
0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

15 authors.

Emmanuel MbubaVector Control Product Testing Unit, Environmental Health and Ecological Science, Ifakara Health Institute, P.O. Box 74, Bagamoyo, United Republic of Tanzania. embuba@ihi.or.tz.
Natalia Mañas-ChavernasCenter for Medical Image Analysis & Navigation (CIAN), Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167A, Allschwil, Switzerland.
Sarah J MooreVector Control Product Testing Unit, Environmental Health and Ecological Science, Ifakara Health Institute, P.O. Box 74, Bagamoyo, United Republic of Tanzania.
Philipo David RuzigeVector Control Product Testing Unit, Environmental Health and Ecological Science, Ifakara Health Institute, P.O. Box 74, Bagamoyo, United Republic of Tanzania.
Dickson KobeVector Control Product Testing Unit, Environmental Health and Ecological Science, Ifakara Health Institute, P.O. Box 74, Bagamoyo, United Republic of Tanzania.
Jason MooreVector Control Product Testing Unit, Environmental Health and Ecological Science, Ifakara Health Institute, P.O. Box 74, Bagamoyo, United Republic of Tanzania.
Rose PhilipoVector Control Product Testing Unit, Environmental Health and Ecological Science, Ifakara Health Institute, P.O. Box 74, Bagamoyo, United Republic of Tanzania.
Noela KisokaSwiss Tropical and Public Health Institute, Dar es Salaam, Tanzania.
Gianpaolo PontiggiaSwiss Tropical and Public Health Institute, Kreuzstrasse 2, CH-4123, Allschwil, Switzerland.
Frank ChackyMinistry of Health, National Malaria Control Programme, Dodoma, United Republic of Tanzania.
Charles Dismasi MwalimuMinistry of Health, National Malaria Control Programme, Dodoma, United Republic of Tanzania.
Philippe Claude CattinCenter for Medical Image Analysis & Navigation (CIAN), Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167A, Allschwil, Switzerland.
Julia WollebCenter for Medical Image Analysis & Navigation (CIAN), Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167A, Allschwil, Switzerland.
Robin SandkuehlerCenter for Medical Image Analysis & Navigation (CIAN), Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167A, Allschwil, Switzerland.
Amanda RossSwiss Tropical and Public Health Institute, Kreuzstrasse 2, CH-4123, Allschwil, Switzerland.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThe physical integrity of insecticidal-treated nets (ITNs) is important for creating a barrier against host-seeking mosquitoes and, therefore, influences people's perception of the net's effectiveness and their willingness to use it. Monitoring the physical integrity of ITNs over time provides information for replenishment schedules and purchasing decisions. Currently, the assessment of physical integrity of ITNs is conducted by manually counting holes and estimating their size to class the net as functional or not. This approach is laborious to routinely conduct during field surveys of ITNs. Automated image analysis may provide a rapid assessment of the physical integrity of ITNs but it is not known if the images can capture sufficient information. As a first step, this study aimed to assess the agreement between estimated hole surface areas derived from (1) manually segmented images, (2) manual hole counting compared to (3) ground truth obtained by calibrated close-up shots of individual holes.

methodsThe physical integrity of 75 ITNs purposely selected from an ongoing study was assessed by manual hole counting, image analysis and ground truth. For the image analysis, a graphical user interface was developed and used for the segmentation of holes visible in photographs taken from each side of the net. The hole surface area was then computed from this data. The agreement between the estimates from image analysis and manual hole counting was compared to the ground truth using the Bland-Altman method.

resultsThere was substantial agreement between the manually segmented image analysis estimates and the ground truth hole surface areas. The overall bias was small, with a mean ratio of the hole surface area from image analysis to the ground truth of 0.70, and the 95% limits of agreement ranging from 0.35 to 1.38. Manual hole counting underestimated the hole surface area compared to the ground truth, particularly among nets with holes above 10 cm in diameter.

conclusionImages coupled with manual segmentation contain sufficient information to calculate hole surface area. This lays the groundwork for incorporating automatic hole detection, and then assessing whether this method will offer a fast and objective method for routine assessment of physical integrity of ITNs. While the WHO method underestimated the hole surface area, it remains useful in classifying nets as either serviceable or too torn because the cut-off is specific to this method.

Indexed as

Image Processing, Computer-AssistedInsecticide-Treated BednetsMosquito ControlAnimalsHumansDurabilityFunctional survivalHole countingImage analysisInsecticide-treated netsITNPhysical conditionPhysical integrity

Identifiers

PMID40087683
PMCPMC11909875

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.