Institute for Medical Research, Ministry of Health, Shah Alam 40170, Malaysia.
Ministry of Health, Putrajaya 62590, Malaysia.
Int J Environ Res Public Health. 2022 Mar 23;19(7):3828. doi: 10.3390/ijerph19073828.
This study aimed to describe the characteristics of COVID-19 cases and close contacts during the first wave of COVID-19 in Malaysia (23 January 2020 to 26 February 2020), and to analyse the reasons why the outbreak did not continue to spread and lessons that can be learnt from this experience. Characteristics of the cases and close contacts, spatial spread, epidemiological link, and timeline of the cases were examined. An extended SEIR model was developed using several parameters such as the average number of contacts per day per case, the proportion of close contact traced per day and the mean daily rate at which infectious cases are isolated to determine the basic reproduction number (R) and trajectory of cases. During the first wave, a total of 22 cases with 368 close contacts were traced, identified, tested, quarantine and isolated. Due to the effective and robust outbreak control measures put in place such as early case detection, active screening, extensive contact tracing, testing and prompt isolation/quarantine, the outbreak was successfully contained and controlled. The SEIR model estimated the R at 0.9 which further supports the decreasing disease dynamics and early termination of the outbreak. As a result, there was a 11-day gap (free of cases) between the first and second wave which indicates that the first wave was not linked to the second wave.
这项研究旨在描述 2020 年 1 月 23 日至 2 月 26 日期间马来西亚（马来西亚）第一波 COVID-19 病例和密切接触者的特征，并分析疫情为何没有继续蔓延以及可以从这次经历中吸取的教训。研究人员检查了病例和密切接触者的特征、空间传播、流行病学联系以及病例的时间线。使用平均每天每个病例的接触人数、每天追踪密切接触者的比例以及每天感染病例隔离的平均速度等几个参数，开发了一个扩展的 SEIR 模型，以确定基本繁殖数（R）和病例轨迹。在第一波疫情中，共追踪到 22 例病例，有 368 名密切接触者。由于采取了早期病例检测、主动筛查、广泛接触者追踪、检测和及时隔离/检疫等有效和强大的疫情控制措施，疫情得到了成功控制。SEIR 模型估计的 R 值为 0.9，这进一步支持了疾病动态的下降和疫情的早期结束。因此，第一波和第二波之间有 11 天的间隔（无病例），这表明第一波与第二波没有关联。
