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Table 2 Mortality and knockdown time of An. funestus and An. gambiae from Obout (Cameroon) after 1 h exposure to pyrethroids

From: Elevated Plasmodium infection rates and high pyrethroid resistance in major malaria vectors in a forested area of Cameroon highlight challenges of malaria control

Year Species/strain Insecticide n kdt50 (min) (IC95) kdt95 (min) (IC95) Mortality (%) Status
2015 Kisumu Perm. 0.75% 120 21.2 (16.1–25) 40 (33.88–55.5) 100 S
   Delta. 0.05% 100 18.1 (17.6–18.9) 24.9 (23.4–27.4) 100 S
  An. funestus Perm. 0.75% 152 17.2 (16.8–17.7) 22.4 (21.4–23.8) 94.74a PR
   Delta. 0.05% 101 26.6 (18.2–39.9) 55.2 (37.7–214.7) 76.24b R
  An. gambiae Perm. 0.75% 153 > 60 >> 60 36.6c R
   Delta. 0.05% 124 38.3 (35–41) >> 60 56.45e R
2016 Kisumu Perm. 0.75% 167 21.12 (16.1–24.6) 40.3 (33.88–55.5) 100 S
   Delta. 0.05% 159 18 (17.6–18.9) 24.9 (23.4–27.4) 100 S
  An. funestus Perm. 0.75% 510 29.41 (22.52–38.4) 41.61 (32.15–52.86) 94.12a PR
   Delta. 0.05% 573 39.62 (20.6–54.19) 55.19 (44.89–90.19) 70.54b R
  An. gambiae Perm. 0.75% 202 > 60 >> 60 6.00d R
   Delta. 0.05% 343 > 60 >> 60 18.65f R
  1. a-f For An. funestus and An. gambiae mortality rates for the same insecticide followed by different letters were significantly different between the two years (Fisher's exact test). All significant differences were at P < 0.0001.
  2. Abbreviations: kdt, Knockdown time; R, resistant; S, susceptible; PR, probably resistant; Perm., permethrin; Delta., deltamethrin.