Mean (± Standard Error) of the number of flies caught by the five individual traps in coffee plantation (bars in white) and village (bars in grey).

<p>Collections among the traps at each site were compared in a pairwise fashion and the statistical significance of differences between the paired trap collections assessed using a t-test. Means with the same letter were not significantly different (p>0.05).</p

Performance of the original and tarpaulin based trap designs.

<p>Symbols present the mean and error bars of the standard error of collections taken over a three-day period. Open circles = collections by the original acrylic sandwich design. Solid circles = collections by the modified tarpaulin based design. Open triangles = human landing collections.</p

Mean ± standard error (SE) of the daily number of <i>Simulium ochraceum s.l.</i> captured over 60 days.

1<p>Flies/trap/day.</p>2<p>Flies/team/day.</p><p>Mean ± standard error (SE) of the daily number of <i>Simulium ochraceum s.l.</i> captured over 60 days.</p

Original and modified Esperanza trap designs.

<p>Panel A: Original acrylic sandwich design. Panel B: Modified tarpaulin design.</p

Interruption of Transmission of <i>Onchocerca volvulus</i> in the Southern Chiapas Focus, México

<div><p>Background</p><p>The Southern Chiapas focus of onchocerciasis in Southern Mexico represents one of the major onchocerciasis foci in Latin America. All 559 endemic communities of this focus have undergone semi-annual mass treatment with ivermectin since 1998. In 50 communities of this focus, ivermectin frequency shifted from twice to four times a year in 2003; an additional 113 communities were added to the quarterly treatment regimen in 2009 to achieve a rapid suppression of transmission.</p> <p>Methodology/Principal findings</p><p>In-depth epidemiologic and entomologic assessments were performed in six sentinel communities (which had undergone 2 rounds of ivermectin treatment per year) and three extra-sentinel communities (which had undergone 4 rounds of ivermectin treatment per year). None of the 67,924 <i>Simulium ochraceum</i> s.l. collected from this focus during the dry season of 2011 were found to contain parasite DNA when tested by polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA), resulting in an upper bound of the 95% confidence interval (95%-ULCI) of the infective rate in the vectors of 0.06/2,000 flies examined. Serological assays testing for <i>Onchocerca volvulus</i> exposure conducted on 4,230 children 5 years of age and under (of a total population of 10,280 in this age group) revealed that 2/4,230 individuals were exposed to <i>O. volvulus</i> (0.05%; one sided 95% confidence interval = 0.08%).</p> <p>Conclusions/Significance</p><p>The in-depth epidemiological and entomological findings from the Southern Chiapas focus meet the criteria for interruption of transmission developed by the international community.</p> </div

Number of individuals with nodules in the Southern Chiapas focus, Mexico, 1995–2010.

<p>Number of individuals with nodules in the Southern Chiapas focus, Mexico, 1995–2010.</p

In-depth epidemiologic assessments in sentinel and extra-sentinel communities of the Southern Chiapas focus.

<p>In-depth epidemiologic assessments in sentinel and extra-sentinel communities of the Southern Chiapas focus.</p

Prevalence of IgG4 antibodies to Ov16 in the focus of Southern Chiapas, México.

<p>Prevalence of IgG4 antibodies to Ov16 in children 10 years of age and under from sentinel, extra-sentinel, and eight other communities, in migrant workers >15 years of age from three coffee fincas and in children 5 years of age and under from 4 districts in the focus of Southern Chiapas, México.</p>*<p>Skin biopsies were taken and tested by PCR; they contained no parasite DNA (unpublished data).</p

Coverage rate with ivermectin of the eligible population of the Southern Chiapas focus.

<p>The coverage rate, expressed in percent and the 95%-confidence intervals, CIs, surrounding point estimate, with ivermectin of the eligible population of the Southern Chiapas focus, 1995–2011. The line at 85% indicates the coverage needed in a sustained fashion to interrupt transmission.</p

Map of the Southern Chiapas focus, México.

<p>The map of the Southern Chiapas focus shows the six sentinel (marked in yellow) and three extra-sentinel communities (marked in red) and the main rivers and tributaries that might serve as a source of black fly breeding. Map (right) of the Southern Mexico states showing the three onchocerciasis endemic foci.</p