Timeline of the COVID-19 pandemic in 2019
This article documents the chronology and epidemiology of SARS-CoV-2 in 2019, the virus that causes coronavirus disease 2019 (COVID-19) and is responsible for the COVID-19 pandemic. The first human cases of COVID-19 known to have been identified were in Wuhan, Hubei, China, in December 2019. It marked the beginning of the 2019–2020 COVID-19 outbreak in mainland China.
Unconfirmed reports of early cases[edit]
A September 2020 review noted the hypothetical possibility that the COVID-19 infection had already spread to Europe in 2019 by presumptive evidences including pneumonia case numbers and radiology in France and Italy in November and December.[1] However, a subsequent retrospective surveillance report determined there was no evidence of SARS-CoV-2 circulation in Rome (Italy) during this period.[2]
Some medical and environmental analyses in Italy, France, and the US found results which suggested the virus was circulating prior to December 2019 by several weeks. A WHO report states: "the study findings were not confirmed, methods used were not standardized, and serological assays may suffer from non-specific signals". It urges further investigation of these potential early events.[3]
1 December[edit]
Symptoms of the index case, or patient zero, began on 1 December.[9] The man had not been to the Huanan Seafood Wholesale Market. His family was unaffected, and no epidemiological link was found between him and the other laboratory-confirmed cases as of 2 January.[9]
10 December[edit]
Symptoms of three more cases began on 10 December, which were later confirmed by laboratories. These patients are known because they became hospitalized on 16 December and thus sampled. Their results were confirmed two of these three had no direct exposure to the Huanan Seafood Wholesale Market, while the other did.[9]
24 December[edit]
An unresolved clinical case sparks off the first scientific involvement: a bronchoalveolar lavage fluid (BAL) sample was sent from Wuhan Central Hospital to Vision Medicals (广州微远基因科技) in Guangzhou, a private company specializing in metagenomic massive parallel sequencing analysis.[11] According to the GenBank record, the sample was obtained 23 December, whereas Ren et al.,Chin Med J, 2020 sets the date to 24 December 2019.[12][13]
27 December[edit]
First novel disease report[edit]
According to news reports in February 2020—Workers Daily, Global Times—at the Hubei Provincial Hospital of Integrated Chinese and Western Medicine and following the report from Doctor Zhang Jixian, the hospital immediately alerted the local CDC, Wuhan Jianghan Disease Prevention and Control Center,[14] however, the report of 22 January 2020 from the Chinese CDC seems to claim this contact falling on 29 December.[15]
28 December[edit]
First sequencing of genome[edit]
On 28 December 2019, Dr. Lili Ren, a virologist at the Peking Union Medical College in Beijing submitted a complete sequence of SARS-CoV-2 structure to GenBank. The sequence was never made public as it failed to include the annotations required for publication, and attempts by the NIH to contact Dr. Ren went unanswered.[16]
29 December[edit]
On this day and the previous, three similar cases arrived at Hubei Provincial Hospital of Integrated Chinese and Western Medicine, all associated with the seafood market. The health authorities had been informed, and medical experts from Wuhan Jinyintan Hospital, "a hospital designated to treat infectious diseases"[17] came to transfer six of the seven patients. Zhang Jixian took the further initiative to let doctors and nurses in the respiratory department wear face masks, and put out an order for 30 hospital coats of fine canvas.[18] The administration at Hubei Provincial Hospital of Integrated Chinese and Western Medicine convened an interdepartmental panel of doctors, whose conclusions were the cases were unusual and required special attention, and also having learned of two similar cases in the city, decided to report their findings to the municipal and provincial health authorities, Wuhan Municipal Health Commission and Hubei Province Health Committee.[14]
The Wuhan CDC staff found also additional patients with similar symptoms who were linked to the market.[15] The Wuhan 'Center for Disease Control and Prevention' (CDC) is part of Chinese Center for Disease Control and Prevention.
31 December[edit]
First public message[edit]
The Wuhan Municipal Health Commission released a briefing on its website about early signs of a pneumonia outbreak in the city.[29] The message conveys the impression of alertness, by summarizing 30 December's orders to the city hospitals; emphasizing ongoing scientific and clinical investigations and to seek hospital care when having persistent fever while showing symptoms of pneumonia; as well advising the public to wear face masks and to avoid enclosed public places and crowded areas.