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Table 2 Prevalence of P. falciparum in blood donors by diagnostic technique

From: Evaluating 18s-rRNA LAMP and selective whole genome amplification (sWGA) assay in detecting asymptomatic Plasmodium falciparum infections in blood donors

Technique Overall (n = 771) Ada East (n = 149) Ashaiman (n = 164) Ayawaso (n = 155) Ga South (n = 140) Ga West (n = 163) x2 (p value)
Microscopy 59.0 (< 0.01)
 Positive 57 (7.4%) 16 (10.7%) 10 (6.1%) 6 (3.9%) 13 (9.3%) 12 (7.4%)  
 Negative 714 (92.6%) 133 (89.3%) 154 (93.9%) 149 (96.1%) 127 (90.7%) 151 (92.6%)  
Rapid diagnostic test
 Total RDT+ 91 (11.8%) 24 (16.1%) 14 (8.5%) 6 (3.9%) 27 (19.3%) 20 (12.3%) 20.0 (< 0.01)
 PfHRP2+/pLDH+ 36 (39.6%)a 9 (37.5%)a 7 (50.0%)a 2 (33.3%)a 10 (37.0%)a 8 (40.0%)a  
 PfHRP2+/pLDH 52 (57.1%)a 13 (51.2%)a 7 (50.0%)a 4 (66.7%)a 17 (63.0%)a 11 (55.0%)a  
 PfHRP2/pLDH+ 3 (3.3%)a 2 (8.3%)a 0 (0.0%)a 0 (0.0%)a 0 (0.0%)a 1 (5.0%)a  
Molecular assays
 crDNA-LAMP 0.71 (0.399)
  Positive 130 (16.9%) 36 (24.2%) 23 (14.0%) 16 (10.3%) 28 (20.0%) 27 (16.6%)  
  Negative 641 (84.1%) 113 (78.5%) 141 (86.0%) 139 (89.7%) 112 (80.0%) 136 (83.4%)  
 pDNA-LAMP 0.14 (0.707)
  Positive 135 (17.5%) 38 (25.5%) 23 (14.0%) 16 (10.3%) 30 (21.4%) 28 (17.2%)  
  Negative 636 (82.5%) 111 (74.5%) 141 (86.0%) 139 (89.7%) 110 (78.6%) 135 (82.8%)  
 sWGA
  Positive 139 (18.0%) 37 (24.8%) 23 (14.0%) 17 (11.0%) 31 (22.1%) 31 (19.0%)  
  Negative 632 (82.0%) 112 (75.2%) 141 (86.0%) 138 (89.0%) 109 (77.9%) 132 (81.0%)  
Sub-microscopic donor parasitaemia
 Rapid diagnostic test 34 (4.4%) 8 (5.4%) 4 (2.4%) 0 (0.0%) 14 (10.0%) 8 (4.9%) 31.70 (< 0.01)
 crDNA-LAMP 73 (9.5%) 20 (13.4%) 13 (7.9%) 10 (6.4%) 15 (10.7%) 15 (9.2%) 1.12 (0.290)
 pDNA-LAMP 78 (10.1%) 22 (14.7%) 13 (7.9%) 10 (6.4%) 17 (12.1%) 16 (9.8%) 0.22 (0.638)
 sWGA 82 (10.6%) 21 (14.1%) 13 (7.9%) 11 (7.0%) 18 (12.8%) 19 (11.6%)  
  1. RDT rapid diagnostic test, PfHRP2 Plasmodium falciparum specific histidine rich protein 2, pLDH Plasmodium specific lactate dehydrogenase, PfHRP2+/pLDH+ both HRP2 and pLDH detected in donor blood, PfHRP2+/pLDH HRP2 but not pLDH detected in donor blood, PfHRP2/pLDH+ LDH but not HRP2 detected in donor blood (HRP2 gene deletion), crDNA crude DNA extract, pDNA purified DNA extract, sWGA selective whole genome amplification
  2. aPercentages calculated from the total number of donors tested positive by the RDT
  3. x2 is Chi square goodness of fit test statistic. Significance level was determined at p < 0.05