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Table 2 Transmission by Pulex irritans infected using human blood and subsequently fed sterile human blood every 2 days (group II)

From: Poor vector competence of the human flea, Pulex irritans, to transmit Yersinia pestis

Day post-infection Total fleas Fed flea number Infection rate (%) Mean CFU/flea Blocked (B) fleas Partially blocked (PB) fleas B + PB fleas (%) Total CFU transmitted CFU transmitted per fed flea
Exp#1 (fox; Fig. 2A)
 0 292 119 85 1.8 × 105
 2 126 105 90 7.6 × 105 0 0 0 0 0
 4 108 80 ND ND 0 0 0 0 0
 6 94 71 ND ND 0 0 0 0 0
 8 84 66 80 9.5 × 105 0 0 0 0 0
 10 57 41 ND ND 0 0 0 0 0
 12 62 40 ND ND 0 0 0 0 0
 14 47 46 ND ND 0 0 0 0 0
 16 44 43 ND ND 0 0 0 0 0
 18 39 36 ND ND 0 0 0 0 0
 20 37 22 ND ND 0 0 0 0 0
 22 31 25 ND ND 0 0 0 0 0
 24 27 25 ND ND 0 0 0 8 0.3
 26 20 16 50 2.0 × 106 0 0 0 0 0
Exp #2 (owl; Fig. 2B)
 0 21 12 100 1.4 × 106
 2 12 7 ND ND 0 0 0 0 0
 4 12 11 50 1.7 × 106 0 0 0 0 0
 6 6 4 0 0 0 0 0 0 0
  1. ND not determined. The source of the fleas used for the experiments (owl or fox) is indicated