Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh; The Kirby Institute, University of New South Wales, Sydney, Australia.
Mathematical Modeling of Infectious Diseases Unit, Institut Pasteur, Paris, France.
Int J Infect Dis. 2020 Aug;97:306-312. doi: 10.1016/j.ijid.2020.05.111. Epub 2020 Jun 2.
Outbreak investigations typically focus their efforts on identifying cases that present at healthcare facilities. However, these cases rarely represent all cases in the wider community. In this context, community-based investigations may provide additional insight into key risk factors for infection, however, the benefits of these more laborious data collection strategies remains unclear.
We used different subsets of the data from a comprehensive outbreak investigation to compare the inferences we make in alternative investigation strategies.
The outbreak investigation team interviewed 1,933 individuals from 460 homes. 364 (18%) of individuals had symptoms consistent with chikungunya. A theoretical clinic-based study would have identified 26% of the cases. Adding in community-based cases provided an overall estimate of the attack rate in the community. Comparison with controls from the same household revealed that those with at least secondary education had a reduced risk. Finally, enrolling residents from households across the community allowed us to characterize spatial heterogeneity of risk and identify the type of clothing usually worn and travel history as risk factors. This also revealed that household-level use of mosquito control was not associated with infection.
These findings highlight that while clinic-based studies may be easier to conduct, they only provide limited insight into the burden and risk factors for disease. Enrolling people who escaped from infection, both in the household and in the community allows a step change in our understanding of the spread of a pathogen and maximizes opportunities for control.
暴发调查通常集中精力识别在医疗机构就诊的病例。然而，这些病例很少代表社区中所有的病例。在这种情况下，基于社区的调查可能会提供有关感染关键风险因素的更多见解，然而，这些更费力的数据收集策略的好处尚不清楚。
我们使用全面暴发调查的不同数据子集来比较替代调查策略中的推断。
暴发调查小组对来自 460 户家庭的 1933 人进行了访谈。460 户家庭中有 364 人（18%）出现符合基孔肯雅热症状。理论上的以诊所为基础的研究将确定 26%的病例。加入基于社区的病例提供了社区中总体发病率的估计。与同一家庭的对照进行比较表明，至少受过中等教育的人患病风险降低。最后，招募来自整个社区家庭的居民使我们能够描述风险的空间异质性，并确定通常穿着的衣服类型和旅行史作为风险因素。这也表明家庭层面使用蚊虫控制与感染无关。
这些发现强调，虽然以诊所为基础的研究可能更容易进行，但它们仅提供了对疾病负担和风险因素的有限了解。招募那些从家庭和社区中逃脱感染的人，可以让我们对病原体的传播有一个更深入的理解，并最大限度地提高控制的机会。
