Effectiveness and durability of Interceptor® long-lasting insecticidal nets in a malaria endemic area of central India
Effectiveness and durability of Interceptor® long-lasting insecticidal nets in a malaria endemic area of central India
复制标题
DOI：
10.1186/1475-2875-11-189
复制
发表时间：
2012-06-10
期刊：
影响因子：
3
通讯作者：
Kamaraju, Raghavendra
中科院分区：
文献类型：
--
作者：
Bhatt, Rajendra M.;Sharma, Shri N.;Kamaraju, Raghavendra
背景：在本研究中，评估了 Interceptor (R)、长效聚酯网、75 旦尼尔和至少 250 kPa 的破裂强度，涂有 200 mg/m(2) 高效氯氰菊酯，以评估其在印度中部恰蒂斯加尔邦疟疾流行区部落主导的疟疾流行区降低蚊子密度、抑制吸血和疟疾发病率方面的功效。其耐用性、洗涤实践和社区的使用模式也进行了为期三年的评估。 方法：该研究分两个阶段进行。第一阶段（2006年9月至2007年8月），Kanker地区16个疟疾流行村被随机分为三组，即：拦截网 (LN)、未经处理的聚酯网（100 旦尼尔）和无网。通过每两周进行一次家访监测发现疟疾病例，并按照国家禁毒政策进行治疗。每月一次在人类住所通过手工捕捉和除虫菊空间喷雾方法收集蚊子。对三个研究组之间的玻片阳性率 (SPR) 和每 1000 人的疟疾发病率 (PI) 进行比较，以评估使用拦截网的影响。同时，在实验室中通过对洗涤次数高达 20 次的 Interceptor LN 进行锥形生物测定来进行耐洗涤性研究。第二阶段（2008 年 4 月至 2009 年 10 月）在网分发后间隔约 18 个月后开展的活动包括每六个月（即 18、24、30 和 36 个月）进行一次问卷调查，以观察液氮的耐用性、使用模式和社区的洗涤做法。经过36个月的现场使用，回收30张蚊帐并进行破坏性取样进行化学分析。结果：与未处理蚊帐和无蚊帐的村庄相比，拦截蚊帐可有效降低主要疟疾病媒库氏按蚊的密度、胎次率和吸血成功率。 LN 村庄的 SPR 为 3.7%，而未处理的村庄为 6.5%，无网村庄为 11%。 LN 村庄的 PI 为 16.4，而未处理聚酯网和无网村庄的 PI 分别为 24.8 和 44.2。在初次分发三年后进行的调查中，78.7%（737/936）的家庭仍然拥有蚊帐，其中 68% 每晚都使用。一个。在实验室中对洗涤最多 20 次的 LN 进行的锥形生物测定中，库利西病死亡率>80%。家庭使用三年后取出的拦截器 LN 的平均α-氯氰菊酯含量为 43.5 +/- 31.7 mg/m(2)，而基线规格为 200 mg/m(2)。随着使用时间的增加，有孔蚊帐的比例逐渐增加。结论：拦截网对于降低研究村庄的病媒密度和疟疾发病率非常有效。 78% 的蚊帐可用性以及处于可用状态的家庭清楚地表明 Interceptor LN 在印度农村环境中的耐用性可达三年。家庭使用三年后，发现这些蚊帐含有有效浓度的高效氯氰菊酯，可对抗疟疾媒介。
Background: In the present study, Interceptor (R), long-lasting polyester net, 75 denier and bursting strength of minimum 250 kPa coated with alpha-cypermethrin @ 200 mg/m(2) was evaluated for its efficacy in reducing the mosquito density, blood feeding inhibition and malaria incidence in a tribal dominated malaria endemic area in Chhattisgarh state, central India. Its durability, washing practices and usage pattern by the community was also assessed up to a period of three years.Methods: The study was carried out in two phases. In the first phase (September 2006 to August 2007), 16 malaria endemic villages in district Kanker were randomized into three groups, viz. Interceptor net (LN), untreated polyester net (100 denier) and without net. Malaria cases were detected by undertaking fortnightly surveillance by home visits and treated as per the national drug policy. Mosquito collections were made by hand catch and pyrethrum space spray methods from human dwellings once every month. Slide positivity rate (SPR) and malaria incidence per 1000 population (PI) were compared between the three study arms to assess the impact of use of Interceptor nets. Simultaneously, wash resistance studies were carried out in the laboratory by doing cone bioassays on Interceptor LNs washed up to 20 times. Activities undertaken in second Phase (April 2008 to October 2009) after an interval of about 18 months post-net distribution included questionnaire based surveys at every six months, i.e. 18, 24, 30 and 36 months to observe durability, usage pattern of LNs and washing practices by the community. After 36 months of field use, 30 nets were retrieved and sampled destructively for chemical analysis.Results: Interceptor nets were found effective in reducing the density, parity rate and blood feeding success rate of main malaria vector Anopheles culicifacies as compared to that in untreated net and no net villages. SPR in LN villages was 3.7% as compared to 6.5% in untreated and 11% in no net villages. PI in LN villages was 16.4 in comparison to 24.8 and 44.2 in untreated polyester net and no net villages respectively. In surveys carried out after three years of initial distribution, 78.7% (737/936) nets were still in possession with the households, of which 68% were used every night. An. culicifacies mortality was >80% in cone bioassays done on LNs washed up to 20 times in laboratory. Mean alpha-cypermethrin content was 43.5 +/- 31.7 mg/m(2) on Interceptor LNs withdrawn after three years of household use against the baseline specification of 200 mg/m(2). A gradual increase in the proportion of holed nets was observed with the increased period of usage.Conclusion: Interceptor nets were highly effective in reducing vector densities as well as malaria incidence in the study villages. Availability of 78% nets with the households in usable condition clearly indicated durability of Interceptor LNs up to three years in the rural setting of India. The nets were found to contain an effective concentration of alpha-cypermethrin against malaria vector after three years of household use.