Geissbühler Yvonne, Chaki Prosper, Emidi Basiliana, Govella Nicodemus J, Shirima Rudolf, Mayagaya Valeliana, Mtasiwa Deo, Mshinda Hassan, Fillinger Ulrike, Lindsay Steven W, Kannady Khadija, de Castro Marcia Caldas, Tanner Marcel, Killeen Gerry F
Swiss Tropical Institute, Department of Public Health and Epidemiology, Socinstrasse 57, PO Box, 4002 Basel, Switzerland.
Malar J. 2007 Sep 19;6:126. doi: 10.1186/1475-2875-6-126.
Successful malaria vector control depends on understanding behavioural interactions between mosquitoes and humans, which are highly setting-specific and may have characteristic features in urban environments. Here mosquito biting patterns in Dar es Salaam, Tanzania are examined and the protection against exposure to malaria transmission that is afforded to residents by using an insecticide-treated net (ITN) is estimated.
Mosquito biting activity over the course of the night was estimated by human landing catch in 216 houses and 1,064 residents were interviewed to determine usage of protection measures and the proportion of each hour of the night spent sleeping indoors, awake indoors, and outdoors.
Hourly variations in biting activity by members of the Anopheles gambiae complex were consistent with classical reports but the proportion of these vectors caught outdoors in Dar es Salaam was almost double that of rural Tanzania. Overall, ITNs confer less protection against exophagic vectors in Dar es Salaam than in rural southern Tanzania (59% versus 70%). More alarmingly, a biting activity maximum that precedes 10 pm and much lower levels of ITN protection against exposure (38%) were observed for Anopheles arabiensis, a vector of modest importance locally, but which predominates transmission in large parts of Africa.
In a situation of changing mosquito and human behaviour, ITNs may confer lower, but still useful, levels of personal protection which can be complemented by communal transmission suppression at high coverage. Mosquito-proofing houses appeared to be the intervention of choice amongst residents and further options for preventing outdoor transmission include larviciding and environmental management.
成功的疟疾媒介控制取决于对蚊子与人类之间行为相互作用的理解，这种相互作用具有高度的环境特异性，在城市环境中可能具有特征性。本文研究了坦桑尼亚达累斯萨拉姆的蚊子叮咬模式，并估计了使用经杀虫剂处理的蚊帐（ITN）为居民提供的防止疟疾传播暴露的保护效果。
通过在216所房屋中进行人饵诱捕来估计夜间蚊子的叮咬活动，并对1064名居民进行访谈，以确定保护措施的使用情况以及夜间各小时在室内睡觉、室内清醒和室外度过的时间比例。
冈比亚按蚊复合体成员的叮咬活动的每小时变化与经典报告一致，但在达累斯萨拉姆户外捕获的这些媒介的比例几乎是坦桑尼亚农村地区的两倍。总体而言，在达累斯萨拉姆，ITN对嗜外性媒介提供的保护比坦桑尼亚南部农村地区少（59%对70%）。更令人担忧的是，对于当地重要性一般但在非洲大部分地区疟疾传播中占主导地位的阿拉伯按蚊，观察到其叮咬活动高峰出现在晚上10点之前，且ITN对暴露的保护水平低得多（38%）。
在蚊子和人类行为不断变化的情况下，ITN可能提供较低但仍然有用的个人保护水平，高覆盖率的社区传播抑制可以对其进行补充。防蚊房屋似乎是居民首选的干预措施，预防户外传播的其他选择包括杀幼虫和环境管理。
