Strain Characterisation for Measuring Bioefficacy of ITNs Treated with Two Active Ingredients (Dual-AI ITNs): Developing a Robust Protocol by Building Consensus

Rosemary S Lees^{1

2}, Jennifer S Armistead³, Salum Azizi⁴, Edi Constant⁵, Christen Fornadel⁶, John E Gimnig⁷, Janet Hemingway¹, Daniel Impoinvil^{7

8}, Seth R Irish⁸, William Kisinza⁹, Natalie Lissenden^{1

2}, Henry D Mawejje¹⁰, Louisa A Messenger¹¹, Sarah Moore^{12

13

14

15}, Corine Ngufor^{11

16}, Richard Oxborough¹⁷, Natacha Protopopoff¹¹, Hilary Ranson¹, Graham Small⁶, Joseph Wagman¹⁸, David Weetman¹, Sarah Zohdy^{7

8}, Angus Spiers²

Affiliations

¹ Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
² Innovation to Impact, Pembroke Place, Liverpool L3 5QA, UK.
³ U.S. President's Malaria Initiative (PMI), U.S. Agency for International Development (USAID), Washington, DC 20547, USA.
⁴ KCMUCo-PAMVERC Test Facility, Department of Medical Parasitology and Entomology, Kilimanjaro Christian Medical University College, Moshi P.O. Box 2240, Tanzania.
⁵ Centre Suisse de Recherches Scientifiques (CSRS), Abidjan 1303, Côte d'Ivoire.
⁶ Innovative Vector Control Consortium (IVCC), Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK.
⁷ Division of Parasitic Diseases and Malaria, Centers for Disease Control (CDC) and Prevention, Atlanta, GA 30329, USA.
⁸ U.S. President's Malaria Initiative (PMI), Centers for Disease Control (CDC) and Prevention, Atlanta, GA 30329, USA.
⁹ Amani Research Centre, National Institute for Medical Research, Muheza P.O. Box 81, Tanzania.
¹⁰ Infectious Diseases Research Collaboration (IDRC), Plot 2C Nakasero Hill Road, Kampala P.O. Box 7475, Uganda.
¹¹ Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
¹² Vector Control Product Testing Unit (VCPTU), Environmental Health and Ecological Science Department, Ifakara Health Institute, Bagamoyo P.O. Box 74, Tanzania.
¹³ Vector Biology Unit, Department of Epidemiology and Public Health, Swiss Tropical & Public Health Institute, Kreuzstrasse 2, Allschwil, 4123 Basel, Switzerland.
¹⁴ Faculty of Science, University of Basel, Petersplatz 1, 4001 Basel, Switzerland.
¹⁵ Nelson Mandela African Institute of Science and Technology (NM-AIST), Tengeru P.O. Box 447, Tanzania.
¹⁶ Centre de Recherche Entomologique de Cotonou, Cotonou BP 2604, Benin.
¹⁷ PMI VectorLink Project, Abt Associates, 6130 Executive Blvd., Rockville, MD 20852, USA.
¹⁸ Malaria and Neglected Tropical Diseases Program, PATH, Washington, DC 20001, USA.

PMID: 35621770
PMCID: PMC9144861
DOI: 10.3390/insects13050434

Guideline

Strain Characterisation for Measuring Bioefficacy of ITNs Treated with Two Active Ingredients (Dual-AI ITNs): Developing a Robust Protocol by Building Consensus

Rosemary S Lees et al. Insects. 2022.

. 2022 May 6;13(5):434.

doi: 10.3390/insects13050434.

Authors

Affiliations

¹ Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
² Innovation to Impact, Pembroke Place, Liverpool L3 5QA, UK.
³ U.S. President's Malaria Initiative (PMI), U.S. Agency for International Development (USAID), Washington, DC 20547, USA.
⁴ KCMUCo-PAMVERC Test Facility, Department of Medical Parasitology and Entomology, Kilimanjaro Christian Medical University College, Moshi P.O. Box 2240, Tanzania.
⁵ Centre Suisse de Recherches Scientifiques (CSRS), Abidjan 1303, Côte d'Ivoire.
⁶ Innovative Vector Control Consortium (IVCC), Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK.
⁷ Division of Parasitic Diseases and Malaria, Centers for Disease Control (CDC) and Prevention, Atlanta, GA 30329, USA.
⁸ U.S. President's Malaria Initiative (PMI), Centers for Disease Control (CDC) and Prevention, Atlanta, GA 30329, USA.
⁹ Amani Research Centre, National Institute for Medical Research, Muheza P.O. Box 81, Tanzania.
¹⁰ Infectious Diseases Research Collaboration (IDRC), Plot 2C Nakasero Hill Road, Kampala P.O. Box 7475, Uganda.
¹¹ Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
¹² Vector Control Product Testing Unit (VCPTU), Environmental Health and Ecological Science Department, Ifakara Health Institute, Bagamoyo P.O. Box 74, Tanzania.
¹³ Vector Biology Unit, Department of Epidemiology and Public Health, Swiss Tropical & Public Health Institute, Kreuzstrasse 2, Allschwil, 4123 Basel, Switzerland.
¹⁴ Faculty of Science, University of Basel, Petersplatz 1, 4001 Basel, Switzerland.
¹⁵ Nelson Mandela African Institute of Science and Technology (NM-AIST), Tengeru P.O. Box 447, Tanzania.
¹⁶ Centre de Recherche Entomologique de Cotonou, Cotonou BP 2604, Benin.
¹⁷ PMI VectorLink Project, Abt Associates, 6130 Executive Blvd., Rockville, MD 20852, USA.
¹⁸ Malaria and Neglected Tropical Diseases Program, PATH, Washington, DC 20001, USA.

PMID: 35621770
PMCID: PMC9144861
DOI: 10.3390/insects13050434

Abstract

Durability monitoring of insecticide-treated nets (ITNs) containing a pyrethroid in combination with a second active ingredient (AI) must be adapted so that the insecticidal bioefficacy of each AI can be monitored independently. An effective way to do this is to measure rapid knock down of a pyrethroid-susceptible strain of mosquitoes to assess the bioefficacy of the pyrethroid component and to use a pyrethroid-resistant strain to measure the bioefficacy of the second ingredient. To allow robust comparison of results across tests within and between test facilities, and over time, protocols for bioefficacy testing must include either characterisation of the resistant strain, standardisation of the mosquitoes used for bioassays, or a combination of the two. Through a series of virtual meetings, key stakeholders and practitioners explored different approaches to achieving these goals. Via an iterative process we decided on the preferred approach and produced a protocol consisting of characterising mosquitoes used for bioefficacy testing before and after a round of bioassays, for example at each time point in a durability monitoring study. We present the final protocol and justify our approach to establishing a standard methodology for durability monitoring of ITNs containing pyrethroid and a second AI.

Keywords: bioefficacy; dual active ingredients (dual-AI); durability monitoring; insecticide resistance; insecticide-treated nets (ITN); method development; mosquito; product evaluation; pyrethroid; quality control (QC); strain characterisation.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

**Figure 1**
Overview of protocol for characterisation of a pyrethroid resistant strain for use in testing the bioefficacy of a dual-AI ITN, developed by consensus of a group of key stakeholders. Where delayed mortality (scored after more than 24 h) is the endpoint of interest for the second AI, mortality should be scored at this later time point for all elements of the characterisation; mortality may also be scored at 24 h.

See this image and copyright information in PMC

References

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Strain Characterisation for Measuring Bioefficacy of ITNs Treated with Two Active Ingredients (Dual-AI ITNs): Developing a Robust Protocol by Building Consensus

Affiliations

Strain Characterisation for Measuring Bioefficacy of ITNs Treated with Two Active Ingredients (Dual-AI ITNs): Developing a Robust Protocol by Building Consensus

Authors

Affiliations

Abstract

Conflict of interest statement

Figures

References

Publication types

Grants and funding

LinkOut - more resources

Full Text Sources