Final sample classification, HIV prevalence, and estimated annual HIV incidence.

<p>Abbreviations: MAA: multi-assay algorithm; ARV: antiretroviral drug.</p>a<p>The HIV status of study participants was initially characterized based on the results of the two HIV rapid tests performed in-country (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068349#s2" target="_blank">Methods</a>). The testing algorithms used to classify samples according to HIV infection status are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068349#pone-0068349-g001" target="_blank">Figures 1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068349#pone-0068349-g002" target="_blank">2</a>.</p>b<p>Samples classified as MAA positive (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068349#pone-0068349-g001" target="_blank">Figure 1</a>) were tested for the presence of ARV drugs (see text).</p>c<p>Two samples did not have sufficient volume remaining for testing and four samples failed testing; these were included in the analysis as incident infections.</p>d<p>Incident infections include acute infections, early infections (confirmed infections with indeterminate Western blots), and established infections classified MAA positive (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068349#pone-0068349-g002" target="_blank">Figure 2</a>) that either had no ARV drugs detected or no ARV test result (shown in bold).