Updated:03/26/2020 18: 00h
An analysis of mobility and epidemiological data carried out by a worldwide consortium of researchers, led by the Oxford University and Northeastern University (UK), has concluded that travel restrictions from the Chinese city of Wuhan, epicenter of the coronary pandemicavirus, they came too late.
According to their findings, the provinces outside Hubei that acted swiftly to test, trace and contain imported Covid-19 cases were best placed to prevent or contain local outbreaks.
Baidu’s mobile geolocation data, combined with an epidemiological dataset, showed that local person-to-person transmission occurred extensively early in the outbreak and was mitigated by drastic control measures. However, with an average incubation period of 5 days, and up to 14 days in some cases, these mobility restrictions did not start to positively impact the data on new cases for more than a week, and things seemed to be getting worse in the 5-7 days immediately after closing, as local transmission was well advanced.
Among the cases reported outside Hubei, 515 cases had a known history of travel to Wuhan and a symptom onset date prior to January 31, compared to only 39 after January 31, illustrating the effect of the travel restrictions in decreasing spread to other Chinese provinces.
“Our findings show that early in the coronavirus outbreak, travel restrictions were effective in preventing the importation of infections from a known source. Nevertheless, once Covid-19 cases began to spread locally, the contribution of new imports was much less“Explains Moritz Kraemer, one of the authors of the work, which has been published in the journal” Science ».
In this context, the researchers are betting on a comprehensive package of measures that is not limited to travel restriction, including restrictions on local mobility, testing, tracing and isolation. «Chinese provinces and other countries that have successfully halted internal transmission of Covid-19 must carefully consider how they will manage to restore travel and mobility to prevent the reintroduction and spread of the disease in their populations.», He warns, in any case.
In this sense, another of the authors, Samuel V. Scarpino, adds that “travel and mobility restrictions are the most useful at first, when local transmission has not yet become a factor”, but that “after transmission is established, the physical distancing and quarantine of the sick will work, but it takes time ».