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Table 1 Seasonal biting density (SBD), prevalence of infective flies, and seasonal transmission potential (STP) of S. metallicum (2007–2009) in the sentinel and extra-sentinels communities of the North-central onchocerciasis focus, Venezuela

From: Interruption of Onchocerca volvulus transmission in Northern Venezuela

Community No. of flies collected* Seasonal biting densityγ(CI)ψ Prevalence of infective fliesδ(CI)ψ Seasonal transmission potentialθ(CI)ψ
Santa Rosa del Sur (Sentinel) 11,370 99,278 0 (0–0.4) 0 (0–19.9)
(87,847 – 112,167)
Extra-sentinel Communitiesσ 12,668 19,554 0 (0–0.3) 0 (0–2.9)
(15,771 – 24,184)
  1. *Collection period (season): Sentinel (September 2007-March 2008) and other (November to December 2009) communities.
  2. ψThe associated 95% Confidence Intervals (CIs) surrounding the point estimate.
  3. γSBD: Mean number (geometric mean) of S. metallicum bites per person per season.
  4. δNumber of positive (heads) for O. volvulus L3 per 2,000 flies examined.
  5. θSTP: SBD x prevalence of infective flies x mean number of L3 per infective fly.
  6. σLa llanada, El Chino and Buena Vista.