Nagoya City University Graduate School of Medicine, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
Nagoya City University West Medical Center, Aichi, Japan.
BMC Infect Dis. 2021 Oct 30;21(1):1124. doi: 10.1186/s12879-021-06822-0.
Understanding the spatiotemporal distribution of emerging infectious diseases is crucial for implementation of control measures. In the first 7 months from the occurrence of COVID-19 pandemic, Vietnam has documented comparatively few cases of COVID-19. Understanding the spatiotemporal distribution of these cases may contribute to development of global countermeasures.
We assessed the spatiotemporal distribution of COVID-19 from 23 January to 31 July 2020 in Vietnam. Data were collected from reports of the World Health Organization, the Vietnam Ministry of Health, and related websites. Temporal distribution was assessed via the transmission classification (local or quarantined cases). Geographical distribution was assessed via the number of cases in each province along with their timelines. The most likely disease clusters with elevated incidence were assessed via calculation of the relative risk (RR).
Among 544 observed cases of COVID-19, the median age was 35 years, 54.8% were men, and 50.9% were diagnosed during quarantine. During the observation period, there were four phases: Phase 1, COVID-19 cases occurred sporadically in January and February 2020; Phase 2, an epidemic wave occurred from the 1st week of March to the middle of April (Wave 1); Phase 3, only quarantining cases were involved; and Phase 4, a second epidemic wave began on July 25th, 2020 (Wave 2). A spatial cluster in Phase 1 was detected in Vinh Phuc Province (RR, 38.052). In Phase 2, primary spatial clusters were identified in the areas of Hanoi and Ha Nam Province (RR, 6.357). In Phase 4, a spatial cluster was detected in Da Nang, a popular coastal tourist destination (RR, 70.401).
Spatial disease clustering of COVID-19 in Vietnam was associated with large cities, tourist destinations, people's mobility, and the occurrence of nosocomial infections. Past experiences with outbreaks of emerging infectious diseases led to quick implementation of governmental countermeasures against COVID-19 and a general acceptance of these measures by the population. The behaviors of the population and the government, as well as the country's age distribution, may have contributed to the low incidence and small number of severe COVID-19 cases.
了解新发传染病的时空分布对于实施控制措施至关重要。自 COVID-19 大流行发生的头 7 个月以来，越南记录的 COVID-19 病例相对较少。了解这些病例的时空分布情况可能有助于制定全球对策。
我们评估了 2020 年 1 月 23 日至 7 月 31 日期间越南 COVID-19 的时空分布。数据来自世界卫生组织、越南卫生部和相关网站的报告。通过传播分类（本地或隔离病例）评估时间分布。通过每个省的病例数及其时间线评估地理分布。通过计算相对风险 (RR) 评估发病率升高的最可能疾病集群。
在观察到的 544 例 COVID-19 病例中，中位年龄为 35 岁，54.8%为男性，50.9%在隔离期间诊断。在观察期间，有四个阶段：第 1 阶段，2020 年 1 月和 2 月 COVID-19 病例零星发生；第 2 阶段，从 3 月第 1 周到 4 月中旬发生了一次疫情（第 1 波）；第 3 阶段，仅涉及隔离病例；第 4 阶段，2020 年 7 月 25 日开始第二次疫情（第 2 波）。第 1 阶段检测到空间聚集，在平福省（RR，38.052）。第 2 阶段，在河内和河静省地区发现了主要的空间聚集（RR，6.357）。第 4 阶段，在热门海滨旅游目的地岘港检测到空间聚集（RR，70.401）。
越南 COVID-19 的空间疾病聚集与大城市、旅游目的地、人员流动和医院感染有关。过去新发传染病爆发的经验导致越南政府迅速实施针对 COVID-19 的对策，民众普遍接受这些对策。民众和政府的行为以及该国的年龄分布可能导致 COVID-19 发病率低且重症病例少。
