Child Health and Development Centre, Makerere University, College of Health Sciences, Kampala, Uganda.
Infectious Diseases Research Collaboration, Kampala, Uganda.
Malar J. 2020 Nov 19;19(1):416. doi: 10.1186/s12936-020-03490-4.
The World Health Organization (WHO) promotes long-lasting insecticidal nets (LLIN) and indoor residual house-spraying (IRS) for malaria control in endemic countries. However, long-term impact data of vector control interventions is rarely measured empirically.
Surveillance data was collected from paediatric admissions at Tororo district hospital for the period January 2012 to December 2019, during which LLIN and IRS campaigns were implemented in the district. Malaria test positivity rate (TPR) among febrile admissions aged 1 month to 14 years was aggregated at baseline and three intervention periods (first LLIN campaign; Bendiocarb IRS; and Actellic IRS + second LLIN campaign) and compared using before-and-after analysis. Interrupted time-series analysis (ITSA) was used to determine the effect of IRS (Bendiocarb + Actellic) with the second LLIN campaign on monthly TPR compared to the combined baseline and first LLIN campaign periods controlling for age, rainfall, type of malaria test performed. The mean and median ages were examined between intervention intervals and as trend since January 2012.
Among 28,049 febrile admissions between January 2012 and December 2019, TPR decreased from 60% at baseline (January 2012-October 2013) to 31% during the final period of Actellic IRS and LLIN (June 2016-December 2019). Comparing intervention intervals to the baseline TPR (60.3%), TPR was higher during the first LLIN period (67.3%, difference 7.0%; 95% CI 5.2%, 8.8%, p < 0.001), and lower during the Bendiocarb IRS (43.5%, difference - 16.8%; 95% CI - 18.7%, - 14.9%) and Actellic IRS (31.3%, difference - 29.0%; 95% CI - 30.3%, - 27.6%, p < 0.001) periods. ITSA confirmed a significant decrease in the level and trend of TPR during the IRS (Bendicarb + Actellic) with the second LLIN period compared to the pre-IRS (baseline + first LLIN) period. The age of children with positive test results significantly increased with time from a mean of 24 months at baseline to 39 months during the final IRS and LLIN period.
IRS can have a dramatic impact on hospital paediatric admissions harbouring malaria infection. The sustained expansion of effective vector control leads to an increase in the age of malaria positive febrile paediatric admissions. However, despite large reductions, malaria test-positive admissions continued to be concentrated in children aged under five years. Despite high coverage of IRS and LLIN, these vector control measures failed to interrupt transmission in Tororo district. Using simple, cost-effective hospital surveillance, it is possible to monitor the public health impacts of IRS in combination with LLIN.
世界卫生组织（WHO）提倡在疟疾流行国家使用长效杀虫蚊帐（LLIN）和室内滞留喷洒（IRS）来控制疟疾。然而，很少有实证数据来衡量长期的病媒控制干预措施的影响。
收集了 2012 年 1 月至 2019 年 12 月期间托罗罗区医院儿科住院患者的监测数据，在此期间，该地区实施了 LLIN 和 IRS 运动。将 1 个月至 14 岁发热患者的疟疾检测阳性率（TPR）在基线和三个干预期（第一次 LLIN 运动；Bendiocarb IRS；以及 Actellic IRS+第二次 LLIN 运动）进行汇总，并使用前后对照分析进行比较。使用中断时间序列分析（ITSA）来确定与 IRS（Bendiocarb+Actellic）联合第二次 LLIN 运动对每月 TPR 的影响，与基线和第一次 LLIN 运动期相比，控制年龄、降雨量、进行的疟疾检测类型。比较了干预间隔与基线 TPR（60.3%）之间的平均和中位数年龄，并自 2012 年 1 月以来观察了年龄趋势。
在 2012 年 1 月至 2019 年 12 月期间 28049 例发热住院患者中，TPR 从基线时的 60%（2012 年 1 月至 2013 年 10 月）下降到最后一个 Actellic IRS 和 LLIN 期（2016 年 6 月至 2019 年 12 月）的 31%。与基线 TPR（60.3%）相比，TPR 在第一次 LLIN 期间（67.3%，差异为 7.0%；95%CI 5.2%，8.8%，p<0.001）更高，在 Bendiocarb IRS 期间（43.5%，差异-16.8%；95%CI-18.7%，-14.9%）和 Actellic IRS 期间（31.3%，差异-29.0%；95%CI-30.3%，-27.6%，p<0.001）更低。ITSA 证实，与 IRS（Bendicarb+Actellic）前（基线+第一次 LLIN）相比，在第二次 LLIN 期间，TPR 的水平和趋势显著下降。阳性检测结果儿童的年龄随时间显著增加，从基线时的平均 24 个月增加到最后一次 IRS 和 LLIN 期间的 39 个月。
IRS 可以对疟疾感染的医院儿科住院患者产生显著影响。有效病媒控制的持续扩大导致疟疾阳性发热儿科住院患者的年龄增加。然而，尽管疟疾检测阳性的住院人数大幅减少，但仍集中在五岁以下儿童。尽管 IRS 和 LLIN 的覆盖率很高，但这些病媒控制措施未能中断托罗罗区的传播。使用简单、具有成本效益的医院监测，可以监测 IRS 与 LLIN 联合使用对公共卫生的影响。
