"We tested the efficacy of those mosquito traps in areas with the highest reported incidence of dengue. In 2011, traps were distributed in Bukidnon—which had recorded 1,216 cases of dengue in 2010. After distribution, the number of cases decreased to 37—that is a 97 percent reduction rate. In the towns of Ballesteros and Claveria in Cagayan, there were 228 cases of dengue in 2010; in 2011, a mere eight cases were recorded. In Catarman, Northern Samar: 434 cases of dengue were reported in 2010. There were a mere four cases in 2011."

Right... The figures seem to good to be true and I remain skeptical. I have failed to find papers evaluating the effect of lethal ovitrap on dengue incidence. The ones I found are on mosquito populations which showed no effect or reduction to around 50% of mosquito populations.

I also have a problem with their indicator. Using DOH reports of dengue cases is not the best way to measure efficacy of this intervention. Dengue fever is probably defined differently from one doctor to another and may change every year. I think the WHO case definition (using the algorithm) is too sensitive and not very specific that it should not be used for research purposes. Seroconversion among a cohort should have been done as this is the best way to determine incidence.

At the very least, I hoped they used a valid control community where they implemented the same dengue program except that  the traps do not contain larvicide.