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Table 4 Summary results of the bioassays with DDT 4%

From: Insecticide resistance in malaria vectors along the Thailand-Myanmar border

Taxa N a % Mortalityb % KDc KDT50d Statuse
An. scanloni (laboratory strain) 50 84 (74–94) 42 (28–56) 63.2 (59.8–69.7) S
An. minimus (s.s.) (laboratory strain) 50 100 (na) 98 (94–100) 38.3 (36.9–39.7) R
An. annularis (s.l.) 0 na na na na
An. barbirostris (s.l.) 435 74 (70–78) 49 (45–54) 61 (59.1–63.2) R
An. hyrcanus (s.l.) 91 57 (47–67) 30 (20–39) 84.2 (70.9–112.1) R
An. jamesii (s.l.) 59 98 (95–100) 88 (80–96) 33.3 (31.3–35.2) S
An. kochi 0 na na na na
An. maculatus (s.l.) 239 99 (97–100) 9 (94–99) 25.5 (23.4–27.4) S
An. minimus (s.l.) 245 100 (na) 100 (na) 23.4 (21.8–24.9) S
An. tessellatus 0 na na na na
An. vagus 133 97 (94–100) 91 (86–96) 35.3 (34–36.6) SR
  1. a N: number of mosquito phenotyped
  2. b % Mortality: mortality rate (expressed in %) after 1 h of exposure to insecticide, recorded following a 24 h observation period; the values between parentheses indicate the 95% confidence interval of the mean mortality rate
  3. c % KD: rate of mosquitoes “knocked down” (KD, expressed in %) recorded after 1 h of exposure to insecticide; the values between parentheses indicate the 95% confidence interval of the mean KD rate
  4. d TKD50: time (expressed in minutes) necessary to “knock down” 50% of the mosquitoes; the values between parentheses indicate the 95% confidence interval of the TDKD50
  5. e Status: resistance status as defined by WHO [37]. Briefly, a mortality in the range 98–100% indicates susceptibility; a mortality between 90 and 97% indicates suspected resistance; a mortality < 90% indicates confirmed resistance as long as 100 specimens have been phenotyped
  6. Abbreviations: na, not applicable; R, resistant; S, suceptible; SR, suspected resistance