Present situation of house dust mites in Dakahlia governorate, Egypt

House dust mites are common inhalant allergens, which can precipitate atopic disease episodes. The present study revealed presence of four mites. These are Dermatophagoides farinae, D. pteronyssinus, Acheles gracilis and Ornithonyssus bacoti. Population densities of different live adult mites were investigated in different house habitats. In urban houses, pyroglyphid mites were the predominant in bedrooms and D. farinae was the most abundant. A. gracilis was more abundant in living rooms followed by D. farinae then D. pteronyssinus. A. gracilis was the most prevalent in kitchens. While in rural houses, O. bacoti was the most abundant species followed by pyroglyphid mites. Since Dermatophagoides species and A. gracilis were present in numbers high enough to allow their ecological consideration, their seasonal abundance in urban bed-rooms was investigated and revealed that both D. farinae and D. pteronyssinus have two peaks of abundance, one slightly higher in spring and the second in autumn. A. gracilis has two peaks but the higher occurred in autumn and the second in spring

Effect of commiphora molmol on adults, egg masses and egg-deposition of biomphalaria arabica under laboratory conditions

Commiphora molmol [Myrrh] has molluscicidal effect on Biomphalaria arabica snails at low concentration [40 ppm] after 48 hours exposure. The number of dead-snails increased with increasing the time of exposure. One day-old egg masses were more susceptible [death 100% with 80 ppm] to the ovicidal effect of C. molmol than the five-day old ones [Death 95% with 80 ppm]. However, the eggs were more resistant to the C. molmol effect than the adult snails, embryogenesis began to stop at 20 ppm and eggs were all killed at 60 and 80 ppm. B. arabica fecundity decreased at 1 ppm. Based on safety to man and animals, C. molmol is recommended as a safe molluscidide