Table 2. Factors associated with children being ‘more susceptible’ than others.
| Factor | Normal | ‘More Susceptible’ | Crude Odds ratio | ||
| N = 295 (79.1%) | N = 78 (20.9%) | (95% confidence intervals) | |||
| Female | 143 (48.5%) | 31 (40%) | 1.42 (0.86–2.37), p = 0.2 | ||
| Bednets (N = 342)Ω | 140 (52.6%) | 40 (52.6%) | 1.0 (0.6–1.7), p = 1.0 | ||
| Transmission* | 105 (35.6%) | 38 (48.7%) | 1.71 (1.03–2.85), p = 0.03 | ||
| Parasitological cross-sectional survey (n = 238). | |||||
| >5,000 par/µl of blood§ | 13 (7.3%) | 13 (22%) | 3.6 (1.5–8.48), p = 0.002 | ||
| Always –veβ | 70 (39.1%) | 7 (11.9%) | 0.21 (0.08–0.5), p<0.001 | ||
| Genetic markers | |||||
| Sickle trait (N = 352) | 36 (13%) | 4 (5.4%) | 0.38 (0.13–1.12), p = 0.07 | ||
| Thalassaemia (N = 284)φ | 148 (67.9%) | 47 (71.2%) | 1.17 (0.6–2.14), p = 0.6 | ||
| Incidence of clinical disease [Episodes/child/year and 95% confidence intervals] | |||||
| Normal | ‘More Susceptible’ | ||||
| Malaria fevers | 0.56 (0.51–0.61) | 2.35 (2.17–2.53) | |||
| Non-malarial fevers | 0.91 (0.85–0.97) | 0.93 (0.81–1.04) | |||
Note:
Bednets either untreated or treated that were in good condition.
*Transmission: This reflects the household level of transmission and shows the proportion of children in the two groups that came from homes with above average parasite rate (≥50%) compared to those below average (<50%).
These are geometric mean parasite densities in those cross-sectional surveys were the slide was positive. The cut-off for high geometric mean parasite density was set arbitrarily at >5,000 parasites/µl of blood compared to those with less
Compares those who were always negative at all six cross-sectional surveys with those who were positive at least once.
α Thalassaemia genotype: Homozygous (-α/-α) and heterozygous (αα/-α) compared to normal (αα/αα). Comparing homozygous and heterozygous alone did not make a difference to these associations.