OBJECTIVETo investigate the prevalence of container breeding mosquitoes with emphasis on the seasonality and larval habitats of Aedes aegypti (Ae. aegypti) in Makkah City, adjoining an environmental monitoring and dengue incidence.

METHODSMonthly visits were performed between April 2008 and March 2009 to randomly selected houses. During each visit, mosquito larvae were collected from indoors and outdoors containers by either dipping or pipetting. Mosquitoes were morphologically identified. Data on temperature, relative humidity, rain/precipitations during the survey period was retrieved from governmental sources and analyzed.

RESULTSThe city was warmer in dry season (DS) than wet season (WS). No rain occurred at all during DS and even precipitations did fall, wetting events were much greater during WS. Larval survey revealed the co-breeding of Aedes, Culex and Anopheles in a variety of artificial containers in and around homes. 32 109 larvae representing 1st , 2nd, 3rd, and 4th stages were collected from 22 618 container habitats. Culicines was far the commonest and Aedes genus was as numerous as the Culex population. Ae. aegypti larval abundance exhibited marked temporal variations, overall, being usually more abundant during WS. Ten types of artificial containers were found with developing larvae. 70% of these habitats were located indoors. 71.42% of indoor containers were permanent and 28.58% was semi-permanent during WS. Cement tanks was the only container type permanent during DS. Ae. aegypti larval indices (CI, HI, BI) recorded were greater during WS.

CONCLUSIONSTaken together, these results indicate a high risk of dengue transmission in the holy city.

Aedes ; Animals ; Culicidae ; Dengue ; transmission ; Ecosystem ; Environmental Monitoring ; Larva ; Prevalence ; Saudi Arabia ; epidemiology ; Seasons ; Weather

Introduction: As the high incidence of breast cancer has a profound impact on a global scale, there is a critical need to improve the clinical outcome of the patients, including efforts to utilize bioactive natural products as treatment or preventive measures. Citral, the essential oil of lemongrass has been reported to possess cytotoxicity in breast cancer cell line . The aim of present study was to determine the capability of citral in targeting aldehyde dehydrogenase-positive (ALDH+) cells in breast cancer cells. Methods: Both MCF-7 and MDA-MB-231 cells were cultured in serum-free media to generate multicellular tumour spheroids for the evaluation of citral as an antiproliferative agent. The cells were treated with identified IC50 (50±4.30 µM and 56±3.17 µM of citral, respectively) to investigate the cytotoxicity of citral. Staining using Propidium Iodide (PI) and Hoechst 33342 was carried out to determine cell proliferation and viability. Finally, ALDH+ cells were quantified via ALDEFLUOR assay. Analysis of differences was carried out by analysis of variance (ANOVA) and independent t-test with p<0.05 considered statistically significant. Results: The size of spheroids in both cancer cell lines were reduced after treatment with the citral. PI and Hoechst 33342 staining also revealed that citral gave rise to a mixture of cells that are normal and undergoing apoptosis and necrosis. ALDEFLUOR assay analysis revealed citral significantly (p <0.05 ) inhibited the population of ALDH+ cells in MCF7 cells. Conclusion: It was demonstrated that citral reduced the ALDH+ cell population in MCF7 breast cancer spheroids by inhibiting the ALDH activity.