When did the new crown first appear

With the deepening of novel coronavirus pneumonia research in the world, the time line of the epidemic development in many countries has been rewritten, and the time points for the diagnosis or the local spread of the disease have been rewritten. When can the new coronavirus first appear?
Japan: antibody positive in blood donation samples in early 2019
Two out of 500 blood samples collected from January to March 2019 in shinyue, Kanto, Japan, were determined to be positive for antibodies against new coronavirus.
As the blood preserved before the outbreak of the new coronavirus, there was also a positive phenomenon of antibody against the new coronavirus. Therefore, houlao province believed that it was difficult to determine the performance of the kit and the proportion of antibody existed only from this result. It was planned to carry out a large-scale antibody test for 10000 people starting from next month. In addition to Tokyo and Osaka, where the number of infected people was relatively small, it was also listed Enter the candidate.
Novel coronavirus infection was first identified in Japan, China’s more than 30 year old Chinese man who had traveled to Wuhan and is currently living in Kanagawa, Japan, in January 16, 2020.
Spain: detection of new coronavirus in wastewater in March 2019
On June 26, a team from the University of Barcelona in Spain announced that there were traces of the new coronavirus in the wastewater collected on March 12, 2019, while Spain did not report the first confirmed case until February 25 this year.
Alvette bosh, a biology professor at the University of Barcelona, who led the study, said in an exclusive interview with Xinhua News Agency on the 29th that the results of the study showed that the new coronavirus may “have started to spread without people’s awareness”, but because its infection symptoms are similar to those of respiratory diseases such as influenza, people did not realize its existence at that time.
The results of the study have been submitted for peer review, but at the same time, many scientists have questioned the use of a single sample, which weakens the reliability of the results and makes it impossible to conduct repeated tests to confirm the results.
Brazil: a new coronavirus was detected in November last year, three months earlier than the first confirmed case
In July 2nd, the novel coronavirus pneumonia was detected in the sewage samples of the water samples of the sewage water in October last year in March, which was found in the state of Brazil, Santa Catarina, Brazil. The expert group of the Federal University of Santa Catarina announced that it had found a new crown pneumonia virus in the sewage samples of November last year. The results of this study have now been submitted for peer review.
On February 26, Sao Paulo, Brazil’s largest city, confirmed the first new crown case in the country and the first case in Latin America.
Dr. giselene fongaro of the applied Virology Laboratory of the Federal University of Santa Catarina, who was involved in the study, explained that the sample was collected on November 27 last year, and it took weeks for the virus to infect humans, which means that people were already infected 15 to 20 days before the samples were collected.
Gislenni said that the virus detected in the wastewater samples was compared with the genome of four new coronavirus groups, and each sample was tested at least eight times before the virus was confirmed as a new coronavirus. The team came to the conclusion from the applied virology laboratory, and then went to the molecular, microbiological and serological Laboratory of the Federal University Hospital of Santa Catarina, and came to the same conclusion.
France: suspected cases hospitalized in November 2019
Novel coronavirus pneumonia was reproduced in the Albert Schweitzer hospital in early May this year. The total of 2456 chest radiographs taken from November 1st last year to April 30th this year showed that the earliest cases of pneumonia with typical new crown symptoms can be traced back to November 16, 2019.
Novel coronavirus pneumonia is the first case in France to be found in the eastern part of the great eastern region. The first confirmed case was previously reported in February 27th.
UK: the virus may have begun to spread by the end of 2019, the team said
Research teams from University College London and other institutions have analyzed genome data of more than 7500 viruses from people infected with new coronavirus worldwide, and believe that the same ancestor of these new coronaviruses came from the end of 2019. This may be the time when the new coronavirus jumps from nature to human hosts, i.e., the new coronavirus has been widely spread around the world by the end of 2019.