Spatial pattern of severe acute respiratory syndrome in-out flow in 2003 in Mainland China

Abstract

BackgroundSevere acute respiratory syndrome (SARS) spread to 32 countries and regions within a few months in 2003. There were 5327 SARS cases from November 2002 to May 2003 in Mainland China, which involved 29 provinces, resulted in 349 deaths, and directly caused economic losses of $18.3 billion.MethodsThis study used an in-out flow model and flow mapping to visualize and explore the spatial pattern of SARS transmission in different regions. In-out flow is measured by the in-out degree and clustering coefficient of SARS. Flow mapping is an exploratory method of spatial visualization for interaction data.ResultsThe findings were as follows. (1) SARS in-out flow had a clear hierarchy. It formed two main centers, Guangdong in South China and Beijing in North China, and two secondary centers, Shanxi and Inner Mongolia, both connected to Beijing. (2) “Spring Festival travel” strengthened external flow, but “SARS panic effect” played a more significant role and pushed the external flow to the peak. (3) External flow and its three typical kinds showed obvious spatial heterogeneity, such as self-spreading flow (spatial displacement of SARS cases only within the province or municipality of onset and medical locations); hospitalized flow (spatial displacement of SARS cases that had been seen by a hospital doctor); and migrant flow (spatial displacement of SARS cases among migrant workers). (4) Internal and external flow tended to occur in younger groups, and occupational differentiation was particularly evident. Low-income groups of male migrants aged 19–35 years were the main routes of external flow.ConclusionsDuring 2002–2003, SARS in-out flow played an important role in countrywide transmission of the disease in Mainland China. The flow had obvious spatial heterogeneity, which was influenced by migrants’ behavior characteristics. In addition, the Chinese holiday effect led to irregular spread of SARS, but the panic effect was more apparent in the middle and late stages of the epidemic. These findings constitute valuable input to prevent and control future serious infectious diseases like SARS.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-014-0721-y) contains supplementary material, which is available to authorized users.

Effects of school breaks on influenza-like illness incidence in a temperate Chinese region: an ecological study from 2008 to 2015

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Modelling input-output flows of severe acute respiratory syndrome in mainland China

“…The global spread of SARS passed its 10th anniversary in 2013; however, this outbreak left an indelible mark. The deadly coronavirus erupted in Guangdong in November 2002, and it spread to 26 provinces of mainland China and to 32 countries across five continents in a matter of months and this outbreak resulted in 774 deaths [7]. The short-term economic loss in Singapore, Vietnam, Taiwan, China, and elsewhere in Asia was estimated at $30 billion [8].…”

“…Human migration is responsible for the transmission of infectious diseases between humans, and long-range human mobility is a key factor in spatial disease transmission [9][10][11][12]. The input and output of SARS cases primarily caused the SARS transmission across the country [7]. SARS was spread across distant locations in China because infected individuals carried the virus when they changed locations, thereby infecting other people in other areas.…”

“…The present study modelled SARS transmission with an ASIM using input-output flow data to determine its spatial characteristics and potential determinants. We produced input-output flows for SARS based on the spatial location changes of infected individuals in interregional transmission, which reflects the ability of the virus to spread to neighbouring regions [7]. We constructed SARS input-output flows primarily from migrant and hospitalisation flows.…”

Impact of international travel and border control measures on the global spread of the novel 2019 coronavirus outbreak

“…The current COVID-19 outbreak marks the third novel coronavirus emergence in the 21st century, after the 2003 SARS and the 2013 Middle East respiratory syndrome (MERS). The 2003 SARS epidemic originated in China's Guangdong province, resulting in 5,327 cases within the country and 8,096 infections globally (4). In response to its global spread, many countries implemented airport screening, which was later found to be ineffective in slowing the spread of disease (5)(6)(7).…”