Coronavirus outbreak: Over 75,800 people may be infected with the deadly virus in Wuhan alone, claims study
The discrepancy between these estimates of coronavirus infections and reported cases by Chinese authorities could be due to a time lag between infection and appearance of symptoms, delays in infected persons getting medical attention and time taken to confirm cases
The mysterious coronavirus could have already infected over 75,800 people in Wuhan, claim scientists who have studied the spread of the coronavirus infection in Wuhan and beyond.
These findings, published in Lancet, suggest that Chinese authorities may have a lower tally. Official estimates put the total number of cases in Hubei province alone, where Wuhan is located, at 11,177.
Overall, according to figures released by China's National Health Commission, the virus has infected over 17,205 people and killed 361 others in China.
"The apparent discrepancy between our estimates of coronavirus infections and the actual number of confirmed cases in Wuhan could also be due to several other factors," says senior author Professor Gabriel Leung from the University of Hong Kong in a statement.
He adds that factors that are contributing to the differences in the reported case tally include: a time lag between when people get infected and the appearance of symptoms, delays in infected persons getting medical attention and the time taken to confirm cases by laboratory testing.
Estimated spread and future predictions
The team of scientists from Hong Kong calculated the spread of the virus using officially reported coronavirus data and data on domestic and international travel via train, air or road.
"We estimate that 75,815 individuals have been infected in Wuhan as of January 25, 2020," they say. They add that each infected person could be spreading the virus to two to three other people. What is more, the number of people with the infection could double every 6.4 days.
In the study, the team predicted the number of cases that have been exported from Wuhan to other Chinese cities — both within and outside of mainland China.
Their data also factored in the potential effects of various public health measures: the use of face masks, increased personal hygiene and the quarantine measures introduced in Wuhan on January 23.
The scientists found that sealing off Wuhan may have had little impact on preventing the infection from spreading as "multiple major Chinese cities had already been seeded with more than dozens of infections each." This spread could, in turn, trigger local epidemics in those cities.
These cities include Chongqing, Beijing, Shanghai, and Shenzhen, which may have imported 461, 113, 98, 111, and 80 infections from Wuhan, respectively. All of these cities account for over half of all outbound international air travel from China, says the study.
"If the transmissibility of 2019-nCoV is similar nationally and over time, it is possible that epidemics could be already growing in multiple major Chinese cities, with a time lag of one to two weeks behind the Wuhan outbreak," says lead author Professor Joseph Wu from the University of Hong Kong.
They speculate that large cities that share borders or have close transport links to China could also become outbreak epicenters. This, however, could be contained when public health interventions at both the population and personal levels are implemented, explains Wu.