Chowdhury R, Huda M M, Kumar V, Das P, Joshi A B, Banjara M R, Akhter S, Kroeger A, Krishnakumari B, Petzold M, Mondal D, Das M L
National Institute of Preventive and Social Medicine, Mohakhali, Dhaka, Bangladesh.
Ann Trop Med Parasitol. 2011 Jan;105(1):31-5. doi: 10.1179/136485911X12899838683124.
Although, when applied under controlled conditions in India and Nepal, indoor residual spraying (IRS) has been found to reduce sandfly densities significantly, it is not known if IRS will be as effective when applied generally in these countries, via the national programmes for the elimination of visceral leishmaniasis. The potential benefits and limitations of national IRS programmes for the control of sandflies were therefore evaluated in the districts of Vaishali (in the Indian state of Bihar), Sarlahi (in Nepal) and Sunsari (also in Nepal). The use of technical guidelines, levels of knowledge and skills related to spraying operations, insecticide bio-availability on the sprayed surfaces, concentrations of the insecticide on the walls of sprayed houses, insecticide resistance, and the effectiveness of spraying, in terms of reducing sandfly densities within sprayed houses (compared with those found in unsprayed sentinel houses or control villages) were all explored. It was observed that IRS programme managers, at district and subdistrict levels in India and Nepal, used the relevant technical guidelines and were familiar with the procedures for IRS operation. The performance of the spraying activities, however, showed important deficiencies. The results of bio-assays and the chemical analysis of samples from sprayed walls indicated substandard spraying and suboptimal concentrations of insecticide on sprayed surfaces. This was particularly obvious at one of the Nepali study sites (Sunsari district), where no significant vector reduction was achieved. Sandfly resistance to the insecticide used in India (DDT) was widespread but the potential vectors in Nepal remained very susceptible towards a pyrethroid similar to the one used there. The overall short-term effectiveness of IRS was found to be satisfactory in two of the three study sites (in terms of reduction in the densities of the sandfly vectors). Unfortunately, the medium-term evaluation, conducted 5 months after spraying, was probably made invalid by flooding or lime plastering in the study areas. Preparation for, and the monitoring of, the IRS operations against sandfly populations in India and Nepal need to be improved.
虽然在印度和尼泊尔的可控条件下进行室内滞留喷洒（IRS）时，已发现其能显著降低白蛉密度，但通过消除内脏利什曼病的国家计划在这些国家普遍应用时，IRS是否同样有效尚不清楚。因此，在印度比哈尔邦的瓦伊沙利区、尼泊尔的萨拉希区和孙萨里区（也在尼泊尔）评估了国家IRS计划控制白蛉的潜在益处和局限性。研究探讨了技术指南的使用、与喷洒操作相关的知识和技能水平、喷洒表面的杀虫剂生物有效性、喷洒房屋墙壁上的杀虫剂浓度、杀虫剂抗性以及喷洒在降低喷洒房屋内白蛉密度方面的有效性（与未喷洒的哨兵房屋或对照村庄中的白蛉密度相比）。据观察，印度和尼泊尔的地区及分区层面的IRS计划管理人员使用了相关技术指南，并熟悉IRS操作程序。然而，喷洒活动的执行存在重大缺陷。对喷洒墙壁样本的生物测定和化学分析结果表明，喷洒不达标且喷洒表面的杀虫剂浓度未达最佳。这在尼泊尔的一个研究地点（孙萨里区）尤为明显，在那里未实现对白蛉媒介的显著减少。印度使用的杀虫剂（滴滴涕）对白蛉的抗性普遍存在，但尼泊尔的潜在病媒对一种与当地使用的拟除虫菊酯类似的药剂仍非常敏感。在三个研究地点中的两个，IRS的总体短期有效性（就白蛉媒介密度的降低而言）令人满意。不幸的是，喷洒后5个月进行的中期评估可能因研究区域的洪水或石灰粉刷而无效。印度和尼泊尔针对白蛉种群的IRS操作的准备和监测工作需要改进。
