National Vector Borne Diseases Control Programme (Directorate of Health Services), Panaji, Goa, India.
Indian J Med Res. 2010 May;131:711-9.
BACKGROUND & OBJECTIVES: Goa is one of the filariasis endemic states of India. However, information on density pattern and resting behavior of Culex quinquefasciatus Say, the principal vector of filariasis in Goa is lacking. Therefore, current longitudinal study was undertaken to investigate these aspects.
Panaji was divided into six zones and a total of 240 man hours were spent in 60 fixed catching sites to collect the adult Cx. quinquefasciatus mosquitoes on fortnightly basis from indoor resting sites during 2005-06. The female mosquitoes were classified as unfed, fed, semi-gravid and gravid to ascertain the resting behavior of Cx. quinquefasciatus adults. The data were analysed to evaluate the spatio-temporal variations in adult density, abdominal status and indoor resting sites and linked to meteorological variables like temperature, relative humidity, rainfall and number of rainy days.
Cx. quinquefasciatus adults were prevalent perennially in Panaji with highest per man hour density of females (48.6) in February and the lowest density (6.6) in September. Monthly variations in the densities between different months was significant (F=15.3; P<0.05). Rainfall significantly influenced the population of Cx. quinquefasciatus (t=2.63; P<0.05). Fed group and semi-gravid group showed a strong correlation with the relative humidity (P<0.05), rain fall (P<0.05) and number of rainy days (P<0.05). 62.4 per cent of females and 65.1 per cent of males preferred to rest on hanging objects. Spatio-temporal variations in the number of Cx. quinquefasciatus females and males resting on different sites and also the variations in different sites (P<0.05) were significant.
INTERPRETATION & CONCLUSION: The density of female Cx. quinquefasciatus encountered in all the months was higher than the estimated tolerated level of density of 34 per ten man hours up to which there is no risk of filariasis transmission. The strong correlation between the abdominal conditions and relative humidity, rainfall and number of rainy days imply that these meteorological variables significantly influenced the feeding and fecundity of the species. 85.3 per cent of the indoor resting population comprising of fed, semi-gravid and gravid females confirmed the endophilic nature of the species. The preferential resting behavior of both females and males on hanging objects suggest that use of insecticide treated long-lasting bed nets as personal protective measure can be exploited to reduce the density of the vector species.
果阿是印度的一个丝虫病流行州。然而，有关库蚊在果阿的密度模式和休息行为的信息却很缺乏，库蚊是该地区丝虫病的主要传播媒介。因此，本纵向研究旨在调查这些方面。
将帕纳吉分为六个区，在 2005-06 年期间，每个区的 60 个固定捕捉点总共花费 240 人小时，从室内休息场所每隔两周收集一次成蚊。将雌性蚊子分为未进食、进食、半饱血和饱血状态，以确定库蚊成虫的休息行为。分析数据以评估成年密度、腹部状况和室内休息地点的时空变化，并将其与气象变量（如温度、相对湿度、降雨量和雨天数量）相关联。
库蚊成虫在帕纳吉常年存在，女性每小时的最高密度为 48.6（2 月），最低密度为 6.6（9 月）。不同月份的密度逐月变化差异有统计学意义（F=15.3；P<0.05）。降雨对库蚊种群有显著影响（t=2.63；P<0.05）。饱血组和半饱血组与相对湿度（P<0.05）、降雨量（P<0.05）和雨天数量（P<0.05）呈强相关。62.4%的雌性和 65.1%的雄性更喜欢悬挂物上休息。库蚊雌蚊和雄蚊在不同地点休息的数量的时空变化以及不同地点的变化（P<0.05）均有统计学意义。
所有月份女性库蚊的密度都高于估计的 34 只/10 人小时的可容忍密度，在该密度以下不会有传播丝虫病的风险。腹部状况与相对湿度、降雨量和雨天数量之间的强相关性表明，这些气象变量显著影响了该物种的取食和繁殖能力。85.3%的室内休息种群包括饱血、半饱血和饱血的雌性，证实了该物种的内栖性。雌性和雄性都喜欢悬挂物上休息的偏好行为表明，可以利用经杀虫剂处理的长效蚊帐作为个人保护措施来降低媒介物种的密度。
