Frequent Umbilical Cord—Blood and Maternal-Blood Infections with Plasmodium falciparum, P. malariae, and P. ovale in Kenya

Summary of all single-, double-, and triple-species infections detected bypolymerase chain reaction. Parasite combinationNo. of mothers infected ( n p102)No. of newborns (cord blood)infected ( n p 102)Observed Expected x 2 (1 df ) Observed Expected x 2 (1 df )Pf 26 28 0.1 17 20 0.5Pm 3 10 5.2 a 2 12 8.7 a Po 6 9 1.2 4 11 4.5 a Pf 1 Pm 7 10 0.7 5 6 0.1Pf 1 Po 2 9 5.1 a 1 5 3.5Pm 1 Po 4 3 0.2 5 3 1.0Pf 1 Pm 1 Po 11 3 22.1 b 11 2 58.5 b Uninfected 47 30 9.4 a 56 42 4.3 a NOTE. Pf, Plasmodium falciparum; Pm, P. malariae; Po, P. ovale. a P ! .05. b P ! .001. Observed and expected PCR-based numbers of single andmixed species infections in maternal- and cord-blood samplesare compared in table 2. Overall, observed frequency of mixed Plasmodium species infections was significantly differentinbothmaternal-blood (x 2 , , ) and cord-blood (7df p43.9 P ! .0001 x 2 ,7df p76.2, ) samples, compared with the expected P ! .0001frequencies on the basis of their prevalence in the study pop-ulation. As shown in table 2, these results arise from lower-than-expected numbers of