Effects of Drug Policy Changes on Evolution of Molecular Markers of Plasmodium falciparum Resistance to Chloroquine, Amodiaquine, and Sulphadoxine-Pyrimethamine in the South West Region of Cameroon
Table 1
Changes in the frequency of Pfcrt, Pfmdr1, Pfdhfr, and Pfdhps genotypes between the study periods.
Gene
Mutation
Notation
2003–2005
2009–2013
95% CI
value
Pfcrt
K76T
T
96.1 (223/230)
66.9 (174/260)
22.96–35.44
P < 0.0001
K
3.9 (7/230)
33.1 (84/260)
Pfmdr1
N86Y
Y
83.6 (189/226)
45.2 (94/208)
30.09–46.71
P < 0.0001
N
16.4 (37/226)
54.8 (116/208)
Y184F
F
97.3 (217/223)
56 (131/234)
30.09–46.71
P < 0.0001
Y
2.7 (6/233)
44 (103/234)
D1246Y
Y
3.1 (7/226)
0 (0/250)
0.84–5.36
0.02
D
96.9 (219/226)
100 (250/250)
Pfdhfr
N51I
N
3.6 (08/222)
1.2 (3/243)
−0.41–5.21
0.16
I
96.4 (214/222)
98.8 (240/243)
C59R
C
2.3 (05/222)
0 (0/243)
0.33–4.27
0.05
R
97.7 (217/222)
100 (243/243)
S108N
S
0.9 (2/222)
0 (0/243)
−0.34–2.14
0.44
N
99.1 (220/222)
100 (243/243)
Pfdhps
A437G
A
13.3 (30/225)
10 (24/240)
−2.54–9.14
0.33
G
86.7 (195/225)
90 (216/240)
K540E
K
97.8 (220/225)
100 (240/240)
0.28–4.12
P = 0.06
E
2.2 (5/225)
0 (0/240)
Letters represent single letter representation of amino acids in the codons of the drug resistance genes. CI = confidence interval. In the above table, mixed infections are considered to have the mutant genotype.