The age pattern of asexual <i>P. falciparum</i> malaria parasitaemia in febrile and nonfebrile participants.

<p>The horizontal axis shows the age groups and the vertical axis shows prevalence of parasitaemia in each age group. Percentage and 95% confidence intervals of parasite prevalence are shown by the bars.</p

Age specific seroprevalence in participants with and without patent parasitemia seen during the health centre or community surveys.

<p>The horizontal axis shows the age groups and the vertical axis shows seropositive individuals (%) in each age group. Percentage and 95% confidence intervals of seroprevalence are shown by the bars.</p

Background characteristics of the study participants by season and survey.

<p>Background characteristics of the study participants by season and survey.</p

Locations of the catchment villages within the six study areas in The Gambia.

<p>Names of health centres and study areas are shown in red and the dots represent the villages in each study area.</p

Prevalence of malaria parasitaemia in The Gambia by age, season and survey.

<p>Prevalence of malaria parasitaemia in The Gambia by age, season and survey.</p

Correlation between age specific parasite prevalence in the community and health centre surveys.

<p>This was in the six study areas during the wet malaria transmission season in The Gambia (agegroups: <12, 12-, 36-, 72-,132-,192-, 312-, 552- months).</p

Relationship between village specifc parasite prevalence in the community and health centre surveys durng the wet malaria transmission season.

<p>Data points are parasite prevalence in each of the twenty villages used in the study. Some of the ‘village’ data that have been obtained from the heatlth facilities were quite small so that the correlation here has more scatter than it would do if the health-centre sampling had got optimal number per village.</p

Seroprevalence by season in subjects seen during the health centre or community surveys.

<p>The horizontal axis shows the study areas and the vertical axis show the proportion of sero-positive individuals (%) in each study area. Percentage and 95% confidence intervals of seroprevalence are shown by the bars.</p

Characteristics of studies included in the analysis.

<p>Note: * authors' unpublished data. URR, Upper River Region. CRR, Central River Region.</p

Data derived from Basse, Upper River Region studies.

<p>Note: * Incidence per 100000 person-years. UUR, Upper River Region. CRR, Central River Region.</p><p>†Person-years at risk in the placebo group is calculated from Enwere et al. (2006) in which there were 330 episodes of invasive bacterial infection in vaccine and placebo groups with overall incidence of 1009 per 100000 person-years <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010568#pone.0010568-Enwere1" target="_blank">[14]</a>; 0.5× (330/1009×10⁻⁵) = 16501 person-years.</p><p>‡The number of NTS isolates in the placebo group is calculated using the ratio of NTS incidence in placebo (300×10⁻⁵) versus vaccine (262×10⁻⁵) groups = 1.14 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010568#pone.0010568-Enwere1" target="_blank">[14]</a>, and given 92 NTS isolates were detected in both groups. Thus, there were 49 NTS isolates in the placebo group (49/43 = 1.14 and 49+43 = 92).</p><p>§The number of pneumococcal isolates in the placebo group is calculated using the incidence of IPD in placebo (453×10⁻⁵) versus vaccine (256×10⁻⁵) groups = 1.77 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010568#pone.0010568-Enwere1" target="_blank">[14]</a>, and given 94 pneumococcal bloodstream isolates were detected in both groups. Thus, there were 60 pneumococcal isolates in the placebo group (60/34 = 1.77 and 60+34 = 94).</p><p>∥NTS incidence calculated using age-specific incidence from Enwere et al., i.e. 2–5 mo: 408, 6–11 mo: 360, 12–17 mo: 334, 18–23 mo: 293, 24–29 mo: 42, 3–4 years: extrapolated as half the incidence among those 2 years of age, 42/2 = 21, <5 years: [(408/2)+(360/2)+(334/2)+(293/2)+42+21+21]/5 = 156.</p><p>**IPD incidence calculated from age-specific values <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010568#pone.0010568-Enwere1" target="_blank">[14]</a>, 2–5 mo: 363, 6–11 mo: 576, 12–17 mo: 526, 18–23 mo: 351, 24–29 mo: 339, 3–4 yrs: extrapolated as 339/2 = 170. Calculation of <5 years incidence of IPD takes into account that 71% of pneumococcal isolates were derived from blood <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010568#pone.0010568-Enwere1" target="_blank">[14]</a>: 0.71[(363/2)+(576/2)+(526/2)+(351/2)+339+170+170]/5 = 225.</p><p>††authors' unpublished data.</p