论文标题
有效的遏制解释了在中国大陆近期证实的Covid-19
Effective containment explains sub-exponential growth in confirmed cases of recent COVID-19 outbreak in Mainland China
论文作者
论文摘要
最近，中国大陆的Covid-19的爆发的特征是，在流行病的早期阶段，确认病例的独特代数，次指数增加，与预期的最初指数增长与足够大的繁殖率相比。尽管中国大陆受影响的省份之间的案例计数差异很大，但规模法律$ t^μ$令人惊讶地通用，其中一系列指数$μ= 2.1 \ pm0.3 $。这种行为的普遍性表明，尽管有社会，地区，人口统计学，地理和社会经济异质性的中国省，但这次爆发仍由标准流行病学模型未捕获的基本机制主导。我们表明，观察到的缩放定律是有效耗尽易感人群的遏制政策的直接结果。为此，我们引入了一个简约的模型，该模型捕获了有症状感染的个体的隔离，以及响应缓解政策或行为变化的人口隔离。对于广泛的参数，该模型在确认的情况下重现了观察到的缩放定律，并解释了观察到的指数。与经验数据的定量拟合允许鉴定无症状或低症状的，未识别的感染个体的峰值时间，以及基本繁殖数量中局部变化的估计。该模型暗示，在确认的情况下观察到的缩放定律是有效的有效策略和/或系统的行为变化的直接签名，影响了易感人群的很大一部分。这些见解可能有助于实施潜在出口引起的COVID-19中次要爆发或其他新兴传染病的未来爆发中的遏制策略。
The recent outbreak of COVID-19 in Mainland China is characterized by a distinctive algebraic, sub-exponential increase of confirmed cases during the early phase of the epidemic, contrasting an initial exponential growth expected for an unconstrained outbreak with sufficiently large reproduction rate. Although case counts vary significantly between affected provinces in Mainland China, the scaling law $t^μ$ is surprisingly universal, with a range of exponents $μ=2.1\pm0.3$. The universality of this behavior indicates that despite social, regional, demographical, geographical, and socio-economical heterogeneities of affected Chinese provinces, this outbreak is dominated by fundamental mechanisms that are not captured by standard epidemiological models. We show that the observed scaling law is a direct consequence of containment policies that effectively deplete the susceptible population. To this end we introduce a parsimonious model that captures both, quarantine of symptomatic infected individuals as well as population wide isolation in response to mitigation policies or behavioral changes. For a wide range of parameters, the model reproduces the observed scaling law in confirmed cases and explains the observed exponents. Quantitative fits to empirical data permit the identification of peak times in the number of asymptomatic or oligo-symptomatic, unidentified infected individuals, as well as estimates of local variations in the basic reproduction number. The model implies that the observed scaling law in confirmed cases is a direct signature of effective contaiment strategies and/or systematic behavioral changes that affect a substantial fraction of the susceptible population. These insights may aid the implementation of containment strategies in potential export induced COVID-19 secondary outbreaks elsewhere or similar future outbreaks of other emergent infectious diseases.
