ABSTRACT
To analyze the vector surveillance results during the stage of malaria elimination, so as to provide the evidence for assessing the local transmission risk of imported malaria and carrying out the surveillance work after malaria elimination in Jiangsu Province.From 2011 to 2017, the mosquito population was monitored and human biting rates were calculated by the half overnight human baiting trapping method and overnight lamp trapping method in 7 surveillance sites from June to October. The insecticide resistance level was tested by the force contact method recommended by WHO.A total of 5 106 Anopheles mosquitoes were captured by the half over-night human baiting trapping method in the 7 sites from 2011 to 2017, and all the mosquitoes were identified as Anopheles sinensis. The annual human biting rates were 1.075, 0.786, 1.057, 0.787, 0.790, 1.797 and 1.185 mosquitoes/ (human·hour), respectively. Totally 28 186 Anopheles mosquitoes were caught by the overnight lamp trapping method, and all the mosquitoes were An. sinensis. The densities of Anopheles mosquitoes were 57.950, 50.932, 14.800, 4.405, 58.070, 72.406, and 17.145 mosquitoes/ (night·lamp), respectively. In 2012, the resistance indexes of An. sinensis to deltamethrin, DDT and malathion were at R level in Jiangsu Province.The major vector is An. sinensis and no An. anthropophagus is found in Jiangsu Province. An. sinensis has a high level of resistance to deltamethrin, DDT and malathion.
ABSTRACT
Objective To investigate the species,density and distribution of the overwintering adult mosquitoes in Taibaihu District,Jining City. Methods The overwintering adult mosquitoes were monitored by visual observation in Taibaihu District, Jining City from December 2015 to March 2016. The mosquitoes were collected and dissected to observe the body fat accumula?tion and ovarian development situation. Results Totally 1 677 mosquitoes were captured and all of them were Culex pipiens pal?lens. The highest positive rate of overwintering mosquitoes was in sweet potato cellars and greenhouses,with the positive rates of mosquitoes of 98.25%(56/57)and 81.36%(48/59)respectively. The accumulation of the fat body in the female mosquitoes plummeted from late February,and disappeared in middle March. Conclusions The adults of Culex pipiens pallens can over?winter in Taibaihu District,Jining City,and locate in sweet potato cellars and greenhouses mainly. The control work of adult mosquitoes should be strengthened in the overwintering period.
ABSTRACT
Background & objectives: In the present study, Icon®Life net, a long-lasting polyethylene net, 100 denier and bursting strength of minimum 280 kpa incorporated with deltamethrin @ 65 mg/m2 was evaluated for its efficacy in reducing the density of malaria vector Anopheles culicifacies and impact on malaria prevalence in a malaria endemic area of District Gautam Budh Nagar, India. Methods: Wash resistance of Icon® Life LLIN was determined up to 20 serial washings using An. culicifacies in cone bioassays under field conditions. Efficacy of Icon®Life LLIN was determined in the field in three sets of villages in District Gautam Budh Nagar (Uttar Pradesh), India, selected randomly for the intervention with Icon®Life LLIN, untreated nets and a control without any intervention for the period of August 2008–July 2009. Entomological and malariometric indices in all the three villages were compared during pre- and post-intervention periods for one year against An. culicifacies. A survey was also conducted in the village provided with Icon® Life LLIN to assessing the perception of community regarding acceptance of these nets by the community. Results: In cone bioassays on Icon®Life LLIN with An. culicifacies, >95% knockdown within 1 h and 100% mortality after 24 h exposure were reported even after 20× serial washings under field conditions. Results of the field study revealed reduced entry rate, resting density and parity rate of An. culicifacies in the village with Icon®Life LLIN when compared to no net and untreated net villages. Number of malaria cases reported were less in the Icon®Life LLIN used villages when compared to other two villages. The community compliance and acceptance was high and no adverse health events were reported by the households using these nets. Conclusions: Icon® Life LLIN is an effective intervention for the control of An. culicifacies transmitted malaria in India. Long-term studies are indicated for the duration of effectiveness and to ascertain the epidemiological impact of the use of Icon® Life nets.