The earliest time of infection or months ahead of the multi-country new coronavirus, the source is still difficult to determine

On May 4, local time, Guan Yulian, a member of the Canadian and Royal Academy of Internal Sciences and director of the Canadian Medical Experts Coordination Committee to Combat the New Coronavirus, said in an interview with the media that the earliest infection in the United States may have occurred in October last year. Yves Cohen, head of the critical care department at two hospitals in the province of Seine-Saint-Denis, north of Paris, said on May 3rd that there had been confirmed cases of new coronary pneumonia in France at least by the end of December.

New corona outbreak global outbreak, where is the earliest case of infection? This is a problem that countries have been looking for. However, it is difficult to find and verify the earliest cases. Recently, the United States, France, Italy and other countries have experts pointed out that the new coronavirus infection cases found in advance.

The first case refers to an outbreak in line with the definition of cases, the earliest case, it is the entire outbreak can be traced to the starting point, but not necessarily the earliest source of infection before the outbreak, because the outbreak investigation by the environment, personnel and social factors and constraints, the source of infection is often difficult to find, even the first case, in some cases is difficult to determine.

United States: Earliest infection may be in October last year

On May 4, local time, Guan Yulian, a member of the Canadian and Royal Academy of Internal Sciences and director of the Canadian Medical Experts Coordination Committee to Combat the New Coronavirus, said in an interview with the media that the earliest infection in the United States may have occurred in October last year.

Officials in Santa Clara County, Northern California, u.S. officials revealed on April 21, local time, the coroner’s autopsy of the three bodies, all of which had flu-like symptoms, died at home on February 6, February 17 and March 6, respectively, an autopsy found that all three victims were infected with the new coronavirus. Sara Cody, a public health official at the site, said the autopsy results indicated that the bodies of the three victims were believed to have spread widely in the area at the time of their deaths.

“None of the three patients in California who died from the new coronavirus have been to China, ” the Washington Post reported, citing local health officials. The investigation found that the new corona rye outbreak in the United States occurred much earlier than officially announced. If the incubation period for the new coronavirus is three to four weeks, the chain of infection on the West Coast of the United States will begin in early January or mid-January, rather than the first official death of a patient, local health officials said.

France: Cases have occurred by the end of December

Yves Cohen, head of the critical care department at two hospitals in the province of Seine-Saint-Denis, north of Paris, said on May 3rd that there had been confirmed cases of new coronary pneumonia in France at least by the end of December. His team retested PCR serologically samples of nucleic acid tests taken between December and January last year, and found that one of the cases showed positive retests of COVID-19.

The patient was admitted to the Jean Vidier Hospital on 27 December last year with no travel history, no known information about how he was infected and no suspected cases other than his wife. The patient infected his two children, but his wife was not ill. It is also not clear whether it is asymptomatic or not at all. At present, the patient and his family have recovered to health.

“The earliest detection of the outbreak is not directly related to the source of the virus. Zhang Yafei, a second-level researcher at the Shenzhen Health and Health Commission, explained that although Wuhan, China, was the first region to report and dispose of the outbreak, that is, the first to detect and dispose of the outbreak, it does not represent the earliest outbreak. If the outbreak is not reported, not disposed of, does not mean that no outbreak occurred.

The Pasteur Institute genetically sequenced and compared 97 samples of the new French coronavirus collected between 24 January and 24 March, and compared 338 viral genetic sequences published by the Global Shared Influenza Data Initiative to create a map of the virus’s evolutionary tree. A comparative study has found that the new coronavirus circulating in France comes from the evolutionary branch of a virus that has been circulating on the mainland.

Italy: Doctors saw the virus last October

In Italy, which currently has the third highest number of diagnoses in the world, doctors say they have seen the virus in October, November and December. Giuseppe Remuzzi, a leading Italian medical expert, said that some family doctors had first been careful to find that they were exposed to severe pneumonia, unlike 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 was at least spreading in northern Lombardy, Italy, before we knew about the outbreak in China. “

According to Italy’s Ansa news agency reported on March 25, under the coordination of the Lombardy Regional Health Bureau, 14 research centers in the academic paper platform ArXiv jointly published papers show that the new coronavirus as early as January 1, 2020 in Lombardy began to spread. The British journal Nature commented on its website that the outbreak of new coronary pneumonia had been developing in Italy for several weeks before it was discovered. In other words, the new corona virus has become “active” in Italy in December 2019.

On March 17th the scientific journal Nature Medicine published a paper on the origin of the new coronavirus, The Proximity origin of SARS-CoV-2. Robert Garry, a professor at Tulane University School of Medicine and one of the authors, said many thought the virus originated at a seafood market in Wuhan, China, which may be a misunderstanding. “Our analysis and others point to the origins earlier than that. “There must be some cases in that market in Wuhan, but not the source of the virus. “