Buehler Center for Health Policy and Economics, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States.
Feinberg School of Medicine, Northwestern University, Chicago, IL, United States.
JMIR Public Health Surveill. 2021 Apr 27;7(4):e25728. doi: 10.2196/25728.
The COVID-19 pandemic has placed unprecedented stress on economies, food systems, and health care resources in Latin America and the Caribbean (LAC). Existing surveillance provides a proxy of the COVID-19 caseload and mortalities; however, these measures make it difficult to identify the dynamics of the pandemic and places where outbreaks are likely to occur. Moreover, existing surveillance techniques have failed to measure the dynamics of the pandemic.
This study aimed to provide additional surveillance metrics for COVID-19 transmission to track changes in the speed, acceleration, jerk, and persistence in the transmission of the pandemic more accurately than existing metrics.
Through a longitudinal trend analysis, we extracted COVID-19 data over 45 days from public health registries. We used an empirical difference equation to monitor the daily number of cases in the LAC as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano-Bond estimator in R. COVID-19 transmission rates were tracked for the LAC between September 30 and October 6, 2020, and between October 7 and 13, 2020.
The LAC saw a reduction in the speed, acceleration, and jerk for the week of October 13, 2020, compared to the week of October 6, 2020, accompanied by reductions in new cases and the 7-day moving average. For the week of October 6, 2020, Belize reported the highest acceleration and jerk, at 1.7 and 1.8, respectively, which is particularly concerning, given its high mortality rate. The Bahamas also had a high acceleration at 1.5. In total, 11 countries had a positive acceleration during the week of October 6, 2020, whereas only 6 countries had a positive acceleration for the week of October 13, 2020. The TAC displayed an overall positive trend, with a speed of 10.40, acceleration of 0.27, and jerk of -0.31, all of which decreased in the subsequent week to 9.04, -0.81, and -0.03, respectively.
Metrics such as new cases, cumulative cases, deaths, and 7-day moving averages provide a static view of the pandemic but fail to identify where and the speed at which SARS-CoV-2 infects new individuals, the rate of acceleration or deceleration of the pandemic, and weekly comparison of the rate of acceleration of the pandemic indicate impending explosive growth or control of the pandemic. Enhanced surveillance will inform policymakers and leaders in the LAC about COVID-19 outbreaks.
COVID-19 大流行给拉丁美洲和加勒比地区（LAC）的经济、食品系统和医疗保健资源带来了前所未有的压力。现有的监测提供了 COVID-19 病例和死亡人数的代理指标；然而，这些措施使得难以确定大流行的动态以及可能发生疫情爆发的地方。此外，现有的监测技术未能衡量大流行的动态。
本研究旨在提供 COVID-19 传播的额外监测指标，以比现有指标更准确地跟踪大流行传播的速度、加速度、急动度和持久性的变化。
通过纵向趋势分析，我们从公共卫生登记处提取了 45 天的 COVID-19 数据。我们使用经验差分方程来监测 LAC 中每日病例数作为先前病例数、检测水平和每周变化变量的函数，这是基于动态面板模型估计的，该模型通过在 R 中实现 Arellano-Bond 估计器来使用广义矩方法 (GMM) 方法来实施。对 2020 年 9 月 30 日至 10 月 6 日和 2020 年 10 月 7 日至 13 日期间 LAC 的 COVID-19 传播率进行了跟踪。
与 2020 年 10 月 6 日相比，2020 年 10 月 13 日那一周 LAC 的速度、加速度和急动度均有所降低，同时新病例和 7 天移动平均值也有所减少。在 2020 年 10 月 6 日那一周，伯利兹的加速度和急动度最高，分别为 1.7 和 1.8，这尤其令人担忧，因为其死亡率很高。巴哈马的加速度也很高，为 1.5。共有 11 个国家在 2020 年 10 月 6 日那一周的加速为正，而在 2020 年 10 月 13 日那一周只有 6 个国家的加速为正。TAC 总体呈正趋势，速度为 10.40，加速度为 0.27，急动度为-0.31，这些在随后一周分别降至 9.04、-0.81 和-0.03。
新病例、累计病例、死亡和 7 天移动平均值等指标提供了大流行的静态视图，但未能确定 SARS-CoV-2 感染新个体的地点和速度、大流行的加速或减速率，以及每周比较大流行的加速率，这些都表明即将出现爆炸性增长或控制大流行。增强监测将为 LAC 的政策制定者和领导人提供有关 COVID-19 疫情的信息。
