الفهرس 
lymphatic filariasisOnly 14 pages are availabe for public view
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Abstract
The distribution of filariasis in the Nile Delta is described as prominently focal with spatial clusters of high endemicity villages.
Differences in prevalence between contiguous apparently similar villages where the vector mosquito, Culex pipiens, is extremely common remains unexplained. The use of vector-based strategies for defining focal areas and evaluating levels of endemicity is an urgent demand, prior to detailed epidemiological surveys.
Mosquito infection with Wuchereria bancrofti is assessed either by microscopic examination of filaria or by peR. In the present study, a DNA-based assay was used to test whether it detects circulating W bancrofti DNA fragments within Culex pipiens that have ingested a filaria infected blood meal, but are free of worms upon dissection, at various intervals post-feeding, and microscopic examination. The W bancrofti specific Ssp 1- peR-based assay proved positive only when dissected individual mosquitoes contained at least one living intact filarial worm, indicating that no circulating W bancrofti DNA fragments within filaria free mosquitoes is detected by this particular assay.
The assay also was used to evaluate relative infection levels between villages by processing wild-caught mosquitoes from two villages in Qaliubiya Governorate with high (El-Qolzom, 10.8 %) and low (Kafr Shorafa, 2.1 %) prevalence of human filariasis. Dry ice-baited CDC light traps and oviposition traps were used to collect outdoor host¬seeking and ovipositing Cx. pipiens, respectively.
Mosquitoes resting within houses were collected by aspiration. Outdoor host-seeking and ovipositing Cx. pipiens were equally abundant in Qol and KSH over a 3¬month period. Density of indoor-resting Cx. pipiens in KSH exceeded by 1.4 fold that in Qol. Overall mosquito abundance did not appear to contribute to the observed difference in filaria prevalence between Qol and KSH. None of the outdoor host-seeking, or ovipositing ex. pipiens, in both Qol and KSH was infected with W bancrofti, as assessed by both dissection and peR. Indoor-resting mosquitoes collected from houses with unknown status of human filariasis (44 in Qol and 37 in KSH) and branded positive by dissection were far behind (2.3 % and 0.0 %,