On May 4 local time, Guan Yulian, academician of the Royal College of internal medicine of Canada and the UK and director of the Coordination Committee of Canadian medical experts in fighting against the new coronavirus, said in an interview with the media that the earliest time of infection in the United States was in October last year. On May 3rd, novel coronavirus pneumonia was confirmed in France at least in late December last year, Yves Cohen, head of critical care unit of two hospitals in Senna, St. Denis, Paris, northern France, on May 3rd.
The first case refers to the first case that meets the definition of a case in an outbreak. It is the starting point for the whole outbreak to be traced, but not necessarily the earliest source of infection in the previous outbreak. Because the outbreak investigation is affected and controlled by factors such as environment, personnel and society, the source of infection is often difficult to find. Even the first case, in some cases, is difficult to finally find determine.
In the global outbreak of the new crown epidemic, where are the first cases of infection? This is a question that countries have been exploring. However, it is difficult to find and verify the earliest cases. A few days ago, experts from the United States, France, Italy and other countries pointed out that the detection time of new coronavirus infection cases was earlier.
United States: the earliest time of infection or last October
On May 4 local time, Guan Yulian, academician of the Royal College of internal medicine of Canada and the UK and director of the Coordination Committee of Canadian medical experts in fighting against the new coronavirus, said in an interview with the media that the earliest time of infection in the United States was in October last year.
According to an official in Santa Clara County, Northern California, US, on April 21, local time, the three bodies dissected by the coroner recently all had flu like symptoms before they died at home on February 6, February 17 and March 6, respectively. The autopsy found that the three dead were all infected with the new coronavirus. Sara Cody, a public health official in the area, said the autopsy of the three bodies showed that at the time of their death, there was believed to have been widespread community transmission.
“None of the three people in California who died of the new coronavirus have been to China,” the Washington Post quoted local health officials as saying The survey found that the outbreak of the new crown in the United States occurred far earlier than the official time. If the incubation period of the new coronavirus is three to four weeks, the West Coast transmission chain of the United States starts in early or mid January, rather than February 29, the first official death, the head of the local health department said.
France: cases may have occurred at the end of December last year
On May 3rd, novel coronavirus pneumonia was confirmed in France at least in late December last year, Yves Cohen, head of critical care unit of two hospitals in Senna, St. Denis, Paris, northern France, on May 3rd. His team found a positive covid-19 in a PCR serologic retest of DNA samples from pneumonia patients collected between December and January last year.
The patient, who was hospitalized at Jean vidier hospital on December 27 last year, has no travel history, does not know how he was infected, and has not been exposed to other suspected cases other than her wife. The patient was infected with two of his children, but his wife was not. It is not clear whether it is asymptomatic or not. At present, the patient and his family have all recovered.
“There is no direct link between the source of the virus and where the outbreak was first detected.” Zhang Yafei, a second-class investigator of Shenzhen Municipal Health Commission, explained that although Wuhan, China is the first region to report and dispose of the epidemic, that is, the first region to detect and dispose of the epidemic, it does not mean that it is the first region to have the epidemic. If there is no report or disposal after the outbreak, it does not mean there is no outbreak.
The Pasteur Institute sequenced and compared the genes of 97 French new coronavirus samples collected from January 24 to March 24, and compared them with 338 virus gene sequences released by the global initiative for sharing influenza data to establish a virus evolution tree map. Through comparative study, it is found that the new coronavirus in France comes from the evolutionary branch of a virus that has been circulating in China.
Italy: doctors saw the virus last October
In Italy, where the number of confirmed cases is the third in the world, doctors say that “the virus was seen in October, November and December.” Giuseppe remuzzi, a well-known Italian medical expert, said that the first family doctors carefully found that the severe pneumonia they were exposed to was different from the common flu. They saw the virus in October, November and December, so it’s been around for a long time. “This means that the virus has spread at least in northern Lombardy, Italy, before we know about the outbreak in China.”
The novel coronavirus began to spread in Italy in January 1, 2020 as early as January 1, 2020, according to a report published by the 14 Lombardia research centers on the platform of ArXiv, according to the report of the Lombardia Health Bureau in March 25th. The novel coronavirus pneumonia has been in Italy for several weeks before it was discovered, the British journal Nature commented on its website. In other words, the new coronavirus has been “active” in Italy since December 2019.
On March 17, natural medicine, a scientific journal, published a paper on the origin of sars-cov-2. Robert Garry, one of the authors, Professor, School of medicine, Tulane University