Department of Internal Medicine, Walter Sisulu University Faculty of Health Sciences, Mthatha, Eastern Cape, South Africa
Internal Medicine, Frere Hospital, East London, Eastern Cape, South Africa.
BMJ Open. 2022 Mar 18;12(3):e058761. doi: 10.1136/bmjopen-2021-058761.
This study assesses the cumulative incidence of SARS-CoV-2 infection among healthcare workers (HCWs) during South Africa's first wave and examines the associated demographic, health-related and occupational risk factors for infection.
Multistage cluster sampling was used in a cross-sectional study to recruit 1309 HCWs from two academic hospitals in the Eastern Cape, South Africa over 6 weeks in November and December 2020. Prior test results for SARS-CoV-2 PCR and participants' characteristics were recorded while a blood sample was drawn for detection of IgG antibodies against SARS-CoV-2 nucleocapsid protein. The primary outcome measure was the SARS-CoV-2 cumulative incidence rate, defined as the combined total of positive results for either PCR or IgG antibodies, divided by the total sample. The secondary outcome was significant risk factors associated with infection.
Of the total participants included in the analysis (n=1295), the majority were women (81.5%), of black race (78.7%) and nurses (44.8%). A total of 390 (30.1%) HCWs had a positive SARS-CoV-2 PCR result and SARS-CoV-2 antibodies were detected in 488 (37.7%), yielding a cumulative incidence of 47.2% (n=611). In the adjusted logistic regression model, being overweight (adjusted OR (aOR)=2.15, 95% CI 1.44 to 3.20), obese (aOR=1.37, 95% CI 1.02 to 1.85) and living with HIV (aOR=1.78, 95% CI 1.38 to 2.08) were independently associated with SARS-CoV-2 infection. There was no significant difference in infection rates between high, medium and low COVID-19 exposure working environments.
The high SARS-CoV-2 cumulative incidence in the cohort was surprising this early in the epidemic and probably related to exposure both in and outside the hospitals. To mitigate the impact of SARS-CoV-2 among HCWs, infection prevention and control strategies should target community transmission in addition to screening for HIV and metabolic conditions.
本研究评估了南非第一波疫情期间医护人员（HCWs）中 SARS-CoV-2 感染的累积发生率，并探讨了感染的相关人口统计学、健康相关和职业危险因素。
采用多阶段聚类抽样，于 2020 年 11 月至 12 月在南非东开普省的两家学术医院招募了 1309 名 HCWs 进行横断面研究。记录了 SARS-CoV-2 PCR 检测的既往检测结果和参与者特征，同时抽取血样检测针对 SARS-CoV-2 核衣壳蛋白的 IgG 抗体。主要结局指标是 SARS-CoV-2 的累积发生率，定义为 SARS-CoV-2 PCR 或 IgG 抗体阳性结果的总和除以总样本。次要结局是与感染相关的显著危险因素。
在纳入分析的总参与者（n=1295）中，大多数为女性（81.5%），黑人（78.7%），护士（44.8%）。共有 390 名（30.1%）HCWs 的 SARS-CoV-2 PCR 结果呈阳性，488 名（37.7%）检测到 SARS-CoV-2 抗体，累积发病率为 47.2%（n=611）。在调整后的逻辑回归模型中，超重（调整后的 OR（aOR）=2.15，95%CI 1.44 至 3.20）、肥胖（aOR=1.37，95%CI 1.02 至 1.85）和 HIV 感染者（aOR=1.78，95%CI 1.38 至 2.08）与 SARS-CoV-2 感染独立相关。在高、中、低 COVID-19 暴露工作环境之间，感染率无显著差异。
在疫情早期，队列中 SARS-CoV-2 的高累积发病率令人惊讶，这可能与医院内外的暴露有关。为了减轻 SARS-CoV-2 对 HCWs 的影响，感染预防和控制策略除了筛查 HIV 和代谢状况外，还应针对社区传播。
