Institute for Public Health of the Federation of Bosnia and Herzegovina, Sarajevo, Bosnia and Herzegovina; Sarajevo School of Science and Technology, Hrasnička cesta 3a, Sarajevo, Bosnia and Herzegovina.
Epiconcept, Paris, France.
Int J Infect Dis. 2021 Nov;112:352-361. doi: 10.1016/j.ijid.2021.09.063. Epub 2021 Sep 29.
The secondary attack rate (SAR) of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was estimated, and the risk factors for infection among members of households with a coronavirus disease 2019 (COVID-19) index case were identified to inform preventive measures.
Between 3 August and 19 December 2020, a household transmission study was implemented based on a standardized World Health Organization protocol. Laboratory-confirmed cases of SARS-CoV-2 infection were recruited through the federal COVID-19 database. Trained contact tracers interviewed index cases and household members to collect information on demographic, clinical and behavioural factors. Contacts were followed up for 28 days to identify secondary infections. SAR was estimated and odds ratios (OR) were calculated for risk factors for transmission.
In total, 383 households and 793 contacts were included in this study. The overall SAR was 17% [95% confidence interval (CI) 14-21]. Contacts had higher risk for infection if the primary case had both cough and runny nose (OR 4.31, 95% CI 1.60-11.63), if the contact was aged 18-49 years (OR 4.67, 95% CI 1.83-11.93), if the contact kissed the primary case (OR 3.16, 95% CI 1.19-8.43), or if the contact shared a meal with the primary case (OR 3.10, 95% CI 1.17-8.27).
These results add to the global literature by providing evidence from a middle-income setting. Standard preventive measures in households with positive cases remain critical to reduce transmission.
估计了严重急性呼吸综合征冠状病毒 2 型（SARS-CoV-2）的二次攻击率（SAR），并确定了 2019 年冠状病毒病（COVID-19）索引病例的家庭成员中感染的危险因素，以提供预防措施。
2020 年 8 月 3 日至 12 月 19 日，根据世界卫生组织的标准化方案实施了家庭传播研究。通过联邦 COVID-19 数据库招募了实验室确诊的 SARS-CoV-2 感染病例。经过培训的接触者对索引病例和家庭成员进行了访谈，以收集人口统计学、临床和行为因素信息。对接触者进行了 28 天的随访，以确定二次感染。估计 SAR 并计算了传播危险因素的比值比（OR）。
本研究共纳入 383 户家庭和 793 名接触者。总体 SAR 为 17%[95%置信区间（CI）14-21]。如果主要病例既有咳嗽又有流鼻涕（OR 4.31，95%CI 1.60-11.63），如果接触者年龄在 18-49 岁（OR 4.67，95%CI 1.83-11.93），如果接触者亲吻了主要病例（OR 3.16，95%CI 1.19-8.43），或者如果接触者与主要病例一起用餐（OR 3.10，95%CI 1.17-8.27），则接触者感染的风险更高。
这些结果通过提供从中等收入国家获得的证据，为全球文献增添了新的内容。在有阳性病例的家庭中采取标准的预防措施仍然是减少传播的关键。
