Table 2. Prevalence and intensity of soil-transmitted helminth infections at baseline and in 2015.
2009a | 2015 | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Hookwormb,h | Ascarisb | Trichurisb | Any STHb,i | Hookwormc,g | Ascarisd | Trichurisd | Any STHe,g | ||||||||||
N = 17097 | N = 17097 | N = 17097 | N = 17097 | N = 16887 | N = 16888 | N = 16888 | N = 16886 | ||||||||||
Prevalence of infection | |||||||||||||||||
n | (%) | N | (%) | n | (%) | n | (%) | N | (%) | n | (%) | n | (%) | n | (%) | ||
5270 | (31.0) | 63 | (0.4) | 41 | (0.2) | 5342 | (31.5) | 1868 | (11.1) | 52 | (0.3) | 62 | (0.4) | 1953 | (11.6) | ||
Intensity of infection | |||||||||||||||||
— among all childrenf | N = 16440 | N = 16640 | N = 16440 | N = 16890 | N = 16890 | N = 16890 | |||||||||||
n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | ||||||||||||
Heavy | 133 | (0.8) | 0 | (0.0) | 2 | (0.0) | — | 14 | (0.1) | 0 | (0.0) | 6 | (0.0) | — | |||
Moderate | 164 | (1.0) | 10 | (0.1) | 7 | (0.0) | — | 38 | (0.2) | 9 | (0.1) | 14 | (0.1) | — | |||
Light | 4915 | (29.9) | 53 | (0.3) | 31 | (0.2) | — | 1816 | (10.8) | 43 | (0.3) | 42 | (0.3) | — | |||
Negative | 10878 | (68.3) | 16374 | (99.6) | 16397 | (99.7) | — | 15019 | (88.9) | 16836 | (99.7) | 16826 | (99.6) | — | |||
Missing | 3 | (0.0) | 3 | (0.0) | 3 | (0.0) | — | 3 | (0.0) | 2 | (0.0) | 2 | (0.0) | — | |||
— among infected children with egg count data | N = 5212 | N = 63 | N = 40 | N = 1868 | N = 52 | N = 62 | |||||||||||
n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | ||||||||||||
Heavy | 133 | (2.6) | 0 | (0.0) | 2 | (5.0) | — | 14 | (0.8) | 0 | (0.0) | 6 | (9.7) | — | |||
Moderate | 164 | (3.2) | 10 | (15.9) | 7 | (17.5) | — | 38 | (2.0) | 9 | (17.3) | 14 | (22.6) | — | |||
Light | 4915 | (94.3) | 53 | (84.1) | 31 | (77.5) | — | 1816 | (97.2) | 43 | (82.7) | 42 | (67.7) | — | |||
Mean EPGg | 570 | 2358 | 1682 | — | 289 | 2027 | 3220 | — | |||||||||
Median EPG | 168 | 120 | 72 | 96 | 144 | 168 | |||||||||||
[range] | [24–36864] | [24–26976] | [24–19896] | [24–9672] | [24–16512] | [24–66432] |
aThe total number of children surveyed in 2009 is 16440, plus an additional 660 children were surveyed in 33 schools in Binah in 2007, for a total of 17100 children at baseline (“2009”). The 2007 survey in Binah evaluated 20 children per school. The 2009 baseline and 2015 follow-up surveys evaluated 15 children per school. In order to allow a direct comparison of the baseline and follow-up surveys, the data from Binah in 2007 were weighted to represent 15 children per school. Therefore, the prevalence estimates at baseline are not exactly equal to the number of children testing positive divided by the number of children surveyed.
bData on all three species of infection are missing for three children in 2009.
cData on hookworm are missing for three children in 2015.
dData on Ascaris and Trichuris are missing for two children in 2015.
eSTH infection status is missing for four children in 2015.
fData on intensity of infection are not available for the 660 children from Binah district in 2007 (baseline). For hookworm: 1–1,999 eggs per gram of stool (epg) = light infection; 2,000–3,999 epg = moderate infection; ≥4,000 epg = heavy infection. For Ascaris: 1–4,999 epg = light infection, 5,000–49,999 epg = moderate infection; ≥50,000 epg = heavy infection. For Trichuris: 1–999 epg = light infection; 1,000–9,999epg = moderate infection; ≥10,000 epg = heavy infection.
gEPG = Eggs per gram of stool. Mean = arithmetic mean.
hHookworm prevalence and intensity of infection decreased significantly from baseline to 2015, p<0.001 in both instances.
iPrevalence of any STH infection decreased significantly from baseline to 2015, p<0.001.