At the beginning of the epidemic, the South China seafood market in Wuhan was once considered as the birthplace of the virus, but this view has been denied. With the deepening of virus research in various countries, there is evidence that the United States is the birthplace of COVID-19. As early as the beginning of last year (1 1), COVID-19 may have spread in the United States.
Take Xinjiang as an example:
The epidemic situation in Xinjiang is caused by the exposure of the same source of infection and aggregation activities. These cases are concentrated in Tianshan District, Urumqi, Xinjiang.
The epidemic is characterized by "urgency" The epidemic developed rapidly in the early stage, and the number of cases increased rapidly. After reaching the peak on July 26th to 28th, it began to decline.
The investigation in Wuhan has been successfully concluded, but for COVID-19's tracing work, the trip to Wuhan is not the end, but the starting point.
In June 2020, the University of Barcelona announced that a research team of the university had detected COVID-19 in the wastewater samples collected in Barcelona from 2065438 to March 2009.
In June, 2020, 165438+ 10, Italian researchers published a paper saying that COVID-19 may have spread in the country as early as April, 1965, nearly five months before the first confirmed case of COVID-19 was reported in Italy.
In February, 2020, 65438, the US Centers for Disease Control and Prevention released a government study that COVID-19 was infected in the United States in mid-February, 20 19. In addition, before the first confirmed case was officially reported in Wuhan, early cases were also found in France, Brazil and other countries.
International multi-point tracking is very important for finding and controlling the spread of the epidemic as soon as possible. Before the first confirmed case of COVID-19 was reported in Wuhan, the virus had appeared in many places around the world, which means that WHO experts still need to go to these countries to carry out traceability research and find the real source of the virus.