Department of Geography, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Biology, University of Ottawa, Ottawa, Ontario, Canada.
PLoS One. 2018 Oct 24;13(10):e0205270. doi: 10.1371/journal.pone.0205270. eCollection 2018.
The global implementation of malaria interventions has averted hundreds of millions of clinical malaria cases in the last decade. This study assesses predicted Anopheles mosquito distributions across the United Republic of Tanzania before large-scale insecticide-treated net (ITN) rollouts and indoor residual spraying (IRS) initiatives to determine whether mosquito net usage by children under the age of five and IRS are targeted to areas where historical evidence indicates mosquitoes thrive. Demographic and Health Surveys data from 2011-2012 and 2015-2016 include detailed measurements of mosquito net and IRS use across Tanzania. Anopheline data are far less intensively collected, but we constructed a Maxent-built baseline mosquito habitat suitability (MHS) map (AUC = 0.872) with Tanzanian Anopheles occurrence records from 1999-2003. This MHS model was tested against independently-observed georeferenced Plasmodium falciparum cases from the Malaria Atlas Project, with ~87% of cases from 1999-2003 (n = 107) and ~84% of cases from 1985-2012 (n = 919) occurring in areas of high predicted suitability for mosquitoes. We compared the validated MHS with subsequent malaria interventions using mixed effects logistic regression. Specifically, we assessed whether Anopheles habitat suitability related to the frequency that ≥1 child in a household reportedly slept under a mosquito net when that intervention later became widely available, and whether IRS was reportedly applied to dwellings over a one-year period. There was no evidence that mosquito net use the night before the survey related to MHS from 2011-2012 and marginally significant evidence (p<0.05) from 2015-2016 (β = 1.466, 95% C.I. = 0.848-2.103, marginal R2 = 0.020, respectively). However, the likelihood of IRS treatments rose relatively strongly in the 12 months prior to both surveys (β = 13.466, 95% C.I. = 10.488-16.456, marginal R2 = 0.144, and β = 6.817, 95% C.I. = 5.439-8.303, marginal R2 = 0.136, respectively). IRS treatments have therefore been targeted more effectively than mosquito nets toward areas where anopheline habitat suitability was previously found to be high.
在过去十年中，全球实施的疟疾干预措施避免了数以亿计的临床疟疾病例。本研究评估了坦桑尼亚联合共和国大规模推广杀虫剂处理过的蚊帐（ITN）和室内残留喷洒（IRS）倡议之前预测的按蚊分布情况，以确定五岁以下儿童使用蚊帐和 IRS 是否针对历史证据表明蚊子繁盛的地区。2011-2012 年和 2015-2016 年的人口与健康调查数据包括坦桑尼亚各地使用蚊帐和 IRS 的详细测量。按蚊数据的采集要少得多，但我们使用 1999-2003 年坦桑尼亚按蚊发生记录构建了一个基于最大熵的基线蚊子栖息地适宜性（MHS）地图（AUC=0.872）。该 MHS 模型经过测试与疟疾地图集项目中独立观察到的地理参考间日疟原虫病例进行比较，1999-2003 年约 87%的病例（n=107）和约 84%的病例（n=919）发生在蚊子高度适宜的地区。我们将经过验证的 MHS 与随后的疟疾干预措施进行了比较，使用混合效应逻辑回归。具体来说，我们评估了当该干预措施后来广泛可用时，家庭中报告有≥1 名儿童夜间使用蚊帐的频率与按蚊栖息地适宜性之间是否存在关联，以及在一年期间是否报告对住宅进行 IRS。没有证据表明，在调查前一天晚上使用蚊帐与 2011-2012 年的 MHS 有关，而 2015-2016 年的证据则略有意义（β=1.466，95%CI=0.848-2.103，边际 R2=0.020）。然而，在两次调查之前的 12 个月中，IRS 治疗的可能性相对较强（β=13.466，95%CI=10.488-16.456，边际 R2=0.144，β=6.817，95%CI=5.439-8.303，边际 R2=0.136）。因此，IRS 治疗比蚊帐更有效地针对以前发现按蚊栖息地适宜性较高的地区。
