Werneck Guilherme Loureiro, Figueiredo Fabiano Borges, Cruz Maria do Socorro Pires E
Departament of Epidemiology, State University of Rio de Janeiro, Rio de Janeiro 20950-000, RJ, Brazil.
Instituto for Public Health Studies, Federal University of Rio de Janeiro, Rio de Janeiro 21941-630, RJ, Brazil.
Pathogens. 2024 Feb 1;13(2):135. doi: 10.3390/pathogens13020135.
In Brazil, human visceral leishmaniasis (HVL) is caused by the protozoan parasite , primarily transmitted by the sand fly , with dogs acting as the main urban reservoir. This study aims to evaluate the effectiveness of 4% deltamethrin-impregnated dog collars (DMC) on HVL incidence.
This is a community intervention study carried out from 2012 to 2015 in the municipalities of Araguaína, State of Tocantins, and Montes Claros, State of Minas Gerais, Brazil. Two areas in each were randomly allocated to either (1) culling seropositive dogs + residual insecticide spraying (control area-CA) or (2) culling seropositive dogs + residual insecticide spraying + DMC fitted to dogs every six months for two years (intervention area-IA). Cases of HVL (n = 1202) occurring from 2008 to 2020 were identified from the Brazilian Reportable Diseases Information System and georeferenced to the control and intervention areas. The HVL cases from 2008 to 2012 were considered as occurring in the "pre-intervention" period. Those cases from 2013 to 2016 and from 2017 to 2020 were regarded as occurring in the "intervention" and "post-intervention" periods, respectively. We used a mixed-effects Poisson regression model to estimate the effectiveness of the intervention, comparing the changes from the pre-intervention period to the intervention and post-intervention periods in the control and intervention areas.
In Araguaína, there was a statistically significant reduction in the incidence of HVL in both the control and intervention areas, comparing both the intervention and post-intervention periods with the pre-intervention period. The intervention with DMC was significantly associated with a reduction in HVL when comparing the intervention and pre-intervention periods, yielding an effectiveness estimate of the DMC of 27% (IC95% 1-46%, = 0.045). No differences were observed when comparing the pre- and post-intervention periods ( = 0.827). In Montes Claros, cases reduced in both the control and intervention areas from the pre-intervention period to the intervention period ( = 0.913). In the post-intervention period, the incidence increased in the control area, while cases continued to decrease in the DMC area ( = 0.188).
The use of DMC was associated with a reduction of 27% in the incidence of HVL during the period of DMC delivery, indicating that DMC is effective as an additional strategy for controlling visceral leishmaniasis in Brazil. However, no significant reduction associated with DMC was detected after the intervention period, suggesting that a control program based on the large-scale deployment of DMC might have to be maintained for more extended periods without interruption.
在巴西，人体内脏利什曼病（HVL）由原生动物寄生虫引起，主要通过白蛉传播，犬类是主要的城市宿主。本研究旨在评估4%溴氰菊酯浸渍犬项圈（DMC）对HVL发病率的有效性。
这是一项于2012年至2015年在巴西托坎廷斯州阿拉瓜伊纳市和米纳斯吉拉斯州蒙特斯克拉罗斯市开展的社区干预研究。每个地区的两个区域被随机分配为：（1）扑杀血清阳性犬+残留杀虫剂喷洒（对照区-CA）或（2）扑杀血清阳性犬+残留杀虫剂喷洒+每六个月为犬只佩戴DMC，持续两年（干预区-IA）。从巴西法定传染病信息系统中识别出2008年至2020年发生的HVL病例（n = 1202），并将其地理定位到对照区和干预区。2008年至2012年的HVL病例被视为发生在“干预前”时期。2013年至2016年以及2017年至2020年的病例分别被视为发生在“干预”和“干预后”时期。我们使用混合效应泊松回归模型来估计干预的有效性，比较对照区和干预区从干预前时期到干预期和干预后期的变化。
在阿拉瓜伊纳市，对照区和干预区的HVL发病率在干预期和干预后期与干预前时期相比均有统计学显著下降。将干预期与干预前时期进行比较时，使用DMC的干预措施与HVL发病率降低显著相关，DMC的有效性估计为27%（IC95% 1 - 46%，P = 0.045）。比较干预前和干预后期时未观察到差异（P = 0.827）。在蒙特斯克拉罗斯市，从干预前时期到干预期，对照区和干预区的病例数均减少（P = 0.913）。在干预后期，对照区发病率上升，而DMC区的病例数继续减少（P = 0.188）。
在佩戴DMC期间，使用DMC与HVL发病率降低27%相关，表明DMC作为巴西控制内脏利什曼病的额外策略是有效的。然而，在干预期后未检测到与DMC相关的显著降低，这表明基于大规模部署DMC的控制计划可能需要在更长时间内不间断地维持。
