{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T06:31:43Z","timestamp":1792477903365,"version":"4.5.0"},"reference-count":44,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2021,1,28]],"date-time":"2021-01-28T00:00:00Z","timestamp":1611792000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"LSHTM Athena SWAN Career Restart Fellowship"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>Where resources are available, non-pyrethroid IRS can be deployed to complement standard pyrethroid LLINs with the aim of achieving improved vector control and managing insecticide resistance. The impact of the combination may however depend on the type of IRS insecticide deployed. Studies comparing combinations of pyrethroid LLINs with different types of non-pyrethroid IRS products will be necessary for decision making.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>The efficacy of combining a standard pyrethroid LLIN (DuraNet\u00ae) with IRS insecticides from three chemical classes (bendiocarb, chlorfenapyr and pirimiphos-methyl CS) was evaluated in an experimental hut trial against wild pyrethroid-resistant <jats:italic>Anopheles gambiae<\/jats:italic> s.l. in Cov\u00e9, Benin. The combinations were also compared to each intervention alone. WHO cylinder and CDC bottle bioassays were performed to assess susceptibility of the local <jats:italic>An<\/jats:italic>. <jats:italic>gambiae<\/jats:italic> s.l. vector population at the Cov\u00e9 hut site to insecticides used in the combinations.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>Susceptibility bioassays revealed that the vector population at Cov\u00e9, was resistant to pyrethroids (&lt;20% mortality) but susceptible to carbamates, chlorfenapyr and organophosphates (\u226598% mortality). Mortality of wild free-flying pyrethroid resistant <jats:italic>An<\/jats:italic>. <jats:italic>gambiae<\/jats:italic> s.l. entering the hut with the untreated net control (4%) did not differ significantly from DuraNet\u00ae alone (8%, p = 0.169). Pirimiphos-methyl CS IRS induced the highest mortality both on its own (85%) and in combination with DuraNet\u00ae (81%). Mortality with the DuraNet\u00ae + chlorfenapyr IRS combination was significantly higher than each intervention alone (46% vs. 33% and 8%, p&lt;0.05) demonstrating an additive effect. The DuraNet\u00ae + bendiocarb IRS combination induced significantly lower mortality compared to the other combinations (32%, p&lt;0.05). Blood-feeding inhibition was very low with the IRS treatments alone (3\u20135%) but increased significantly when they were combined with DuraNet\u00ae (61% - 71%, p&lt;0.05). Blood-feeding rates in the combinations were similar to the net alone. Adding bendiocarb IRS to DuraNet\u00ae induced significantly lower levels of mosquito feeding compared to adding chlorfenapyr IRS (28% vs. 37%, p = 0.015).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Adding non-pyrethroid IRS to standard pyrethroid-only LLINs against a pyrethroid-resistant vector population which is susceptible to the IRS insecticide, can provide higher levels of vector mosquito control compared to the pyrethroid net alone or IRS alone. Adding pirimiphos-methyl CS IRS may provide substantial improvements in vector control while adding chlorfenapyr IRS can demonstrate an additive effect relative to both interventions alone. Adding bendiocarb IRS may show limited enhancements in vector control owing to its short residual effect.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0245804","type":"journal-article","created":{"date-parts":[[2021,1,28]],"date-time":"2021-01-28T19:17:24Z","timestamp":1611861444000},"page":"e0245804","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":20,"title":["Which indoor residual spraying insecticide best complements standard pyrethroid long-lasting insecticidal nets for improved control of pyrethroid resistant malaria 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