RationaleSeveral studies have estimated basic production number of novel coronavirus pneumonia MESHD pneumonia HP
(NCP). However, the time-varying transmission TRANS
dynamics of NCP during the outbreak remain unclear.
ObjectivesWe aimed to estimate the basic and time-varying transmission TRANS
dynamics of NCP across China, and compared them with SARS.
MethodsData on NCP cases by February 7, 2020 were collected from epidemiological investigations or official websites. Data on severe acute respiratory syndrome (SARS) cases in Guangdong Province, Beijing and Hong Kong during 2002-2003 were also obtained. We estimated the doubling time, basic reproduction number TRANS
( R0 TRANS
) and time-varying reproduction number TRANS
(Rt) of NCP and SARS.
Measurements and main resultsAs of February 7, 2020, 34,598 NCP cases were identified in China, and daily confirmed cases TRANS
decreased after February 4. The doubling time of NCP nationwide was 2.4 days which was shorter than that of SARS in Guangdong (14.3 days), Hong Kong (5.7 days) and Beijing (12.4 days). The R0 TRANS
of NCP cases nationwide and in Wuhan were 4.5 and 4.4 respectively, which were higher than R0 TRANS
of SARS in Guangdong (R0=2.3), Hongkong (R0=2.3), and Beijing (R0=2.6). The Rt for NCP continuously decreased especially after January 16 nationwide and in Wuhan. The R0 TRANS
for secondary NCP cases in Guangdong was 0.6, and the Rt values were less than 1 during the epidemic.
ConclusionsNCP may have a higher transmissibility TRANS
than SARS, and the efforts of containing the outbreak are effective. However, the efforts are needed to persist in for reducing time-varying reproduction number TRANS
At a Glance CommentaryO_ST_ABSScientific Knowledge on the SubjectC_ST_ABSSince December 29, 2019, pneumonia HP
infection with 2019-nCoV, now named as Novel Coronavirus Pneumonia HP
(NCP), occurred in Wuhan, Hubei Province, China. The disease has rapidly spread from Wuhan to other areas. As a novel virus, the time-varying transmission TRANS
dynamics of NCP remain unclear, and it is also important to compare it with SARS.
What This Study Adds to the FieldWe compared the transmission TRANS
dynamics of NCP with SARS, and found that NCP has a higher transmissibility TRANS
than SARS. Time-varying production number indicates that rigorous control measures taken by governments are effective across China, and persistent efforts are needed to be taken for reducing instantaneous reproduction number TRANS