Results of the change point analysis with a change point at 30 years old.

<p>The vertical dotted/lined line represents the change point at 30 years old; white bars represent proportions of Ab seroconversion whereas grey bars represent proportions of Ab seroreversion; vertical error bars represent the upper and lower limits for the 95% binomial exact confidence interval.</p

Antigen and antibody seroprevalence figures (as based on the results of the Ag-ELISA and the EITB, respectively) by sex and by sampling round.

a<p>CI = Binomial exact 95% Confidence Intervals; SR = sampling round;</p>b<p>SR 1 = June 2009 sampling,</p>c<p>SR 2 = November 2009 Sampling;</p>d<p>SR 3 = July 2010 Sampling.</p

Yearly incidence rates for infection and exposure (as based on the results of Ag-ELISA and EITB, respectively) of individuals who participated in two sampling rounds by period.

a<p>CI = Poisson exact 95% Confidence Intervals;</p>b<p>P1 = June–November period;</p>c<p>P2 = November–July period;</p>d<p>P3 = June–July period.</p

Proportions of Ab seroconversion and seroreversion by time period.

<p>White bars represent proportions of Ab seroconversion whereas grey bars represent proportions of Ab seroreversion; vertical error bars represent the upper and lower limits for the 95% binomial exact confidence interval; Period 1 stands for the period between Sampling round 1 and sampling round 2 (June–November 2009); Period 2 stands for the period between sampling round 2 and sampling round 3 (November 2009–July 2010) and Period 3 stands for the period between sampling round 1 and sampling round 3 (June 2009–July 2010).</p

Proportions of antigen and antibody positive and/or negative individuals who participated in the 3 sampling rounds.

a<p>CI = Binomial exact 95% Confidence Intervals; SR = sampling round;</p>b<p>SR 1 = June 2009 sampling,</p>c<p>SR 2 = November 2009 Sampling;</p>d<p>SR 3 = July 2010 Sampling.</p

Antigen change to seropositivity/seronegativity test result, antibody seroconversions/seroreversion figures (as based on the results of Ag-ELISA and EITB respectively) by period.

a<p>CI = Binomial exact 95% Confidence Intervals;</p>b<p>CI = one-sided, 97.5% confidence interval;</p>c<p>P1 = June–November period;</p>d<p>P2 = November–July period;</p>e<p>P3 = June–July period.</p