The Extent of Transmission of Novel Coronavirus in Wuhan, China, 2020

A cluster of pneumonia cases linked to a novel coronavirus (2019-nCoV) was reported by China in late December 2019. Reported case incidence has now reached the hundreds, but this is likely an underestimate. As of 24 January 2020, with reports of thirteen exportation events, we estimate the cumulative incidence in China at 5502 cases (95% confidence interval: 3027, 9057). The most plausible number of infections is in the order of thousands, rather than hundreds, and there is a strong indication that untraced exposures other than the one in the epidemiologically linked seafood market in Wuhan have occurred.

• JA
  Japan Agency for Medical Research and Development

  Awards: JPMJCR1413, 18H04895, CREST, 17H04701, JP18fk0108050, 17H05808
• MO
  Ministry of Education, Culture, Sports, Science and Technology

  Awards: JPMJCR1413, 17H04701, 19H01074, CREST
• IF
  Inamori Foundation

  Awards: 17H04701, JPMJCR1413
• JS
  Japan Society for the Promotion of Science

  Awards: 18H04895, H.N.: 17H04701, 17H05808, 18H04895 and 19H01074; R.K.: 18J21587, 17H05808, 19H01074, 17H04701, 17H05808, 18H04895 and 19H01074; R.K.: 18J21587, CREST, 18J21587, 17H04701, 17H05808, 18H04895 and 19H01074, 17H04701, JPMJCR1413
• JS
  Japan Science and Technology Agency

  Awards: CREST, JPMJCR1413, 17H04701
• CR
  Core Research for Evolutional Science and Technology

  Award: JPMJCR1413