Many of the recent outbreaks are “person-to-person transmission”, and experts suggest that there are at least three conditions for clinical symptoms

2022-05-04 0 By

On February 3, a press conference on COVID-19 prevention and control in Hangzhou, Zhejiang province, announced that the epidemic has finally reached a turning point. Based on comprehensive analysis, the epidemic has been eradicated in communities, and the next step is to shift from community eradication to quarantine point eradication.On January 28, Lou Xiaoming, deputy director of Zhejiang Center for Disease Control and Prevention, introduced at the provincial epidemic press conference that from the current epidemiological investigation and analysis, the transmission chain of the epidemic is relatively clear.Preliminary judgement spreads by content person, spread by the person’s specific activity again.According to a press conference on COVID-19 prevention and control in Zhejiang province held on the afternoon of January 27, a number of omicron nucleic acid positive samples were found in unused imported materials from Huite (China) Catering Equipment Co., LTD.In addition, a review by Health Times found that there have been a number of recent outbreaks of “human-to-animal transmission”.On January 17, 2022, Beijing announced the tracing of the confirmed cases in Beijing on January 15: None of the cases had any travel history in other provinces or cities within 14 days before onset of illness, and they occasionally sent and received international emails during work.The case reported that she only touched the outer surface of mail package and the first page of document paper, but did not touch the inner surface of package or other paper during this period.Up to now, 22 international mail environmental samples have been collected, including 2 on the outer surface of packaging, 2 on the inner surface and 8 on the paper inside the document. All of them were positive by nucleic acid test, and the specific mutation sites of omicron mutant were detected.Shenzhen, Guangdong: The possibility of infection from foreign goods is high. The press conference on January 10, 2022 in Shenzhen, Guangdong province reported that all the 4 cases were infected with Delta mutant virus and were 100% homologous.Case 1 in this outbreak works in the international supply chain of goods and has a recent history of contact with foreign goods.Based on comprehensive analysis, this outbreak is a domestic one caused by imported coronavirus, and there is a high possibility of infection caused by exposure to novel coronavirus contamination abroad.On January 17, the epidemic prevention and control of shenzhen press conference bulletin, 17 cases of work in the overseas frozen reagents or consignor, January 12, contact and split the Courier from North America, not doing personal protection, 14 sore throat symptoms, 15, nucleic acid early screening positive, do not rule out the outbreaks by exposure to foreign input will be coronavirus pollution items cause the possibility of infection.Ningbo, Zhejiang province: The possibility of human-to-animal transmission is not ruled out, according to a press conference on COVID-19 prevention and control in Ningbo, Zhejiang Province, on January 3, 2022. The genetic sequencing results of the samples of the first case were the Delta variant of COVID-19 virus (AY.57 evolutionary branch), which had a high homology with the genome sequences of the main epidemic strains in Vietnam.The source of the virus is unknown.According to expert analysis and judgment, do not rule out the possibility of “material transmission”.Manzhouli, Inner Mongolia:Preliminary analysis for the foreign goods on November 30, 2021, manzhouli town COVID – 19 epidemic news conference, through a large number of visits, investigation and research, considering the national CDC virus detection and gene sequencing, a preliminary analysis of the outbreak of the manchurian virus for foreign entry goods by descendants “human-to-human transmission,” spread way leading to the outbreak.Novel Coronavirus transmission is really human-to-human?Articles carrying the virus must infect people?Zhao Wei, a professor at the School of Public Health of Southern Medical University, said in an interview with CCTV news 1+1 on January 19, 2022 that as early as October 17, 2020 in the outbreak of COVID-19 in Qingdao, the Chinese Center for Disease Control and Prevention had clearly isolated and cultured novel coronavirus from the outer package of cod transported in the cold chain.There is also relatively clear evidence of novel coronavirus infection in humans.This is the first time in the world to confirm the transmission of goods through the cold chain, there is clear evidence.This evidence was also published in the Journal Proceedings of the Chinese Academy of Sciences, and has been reviewed by scientists. Therefore, the evidence of “physical transmission from person to person” in this case should be relatively precise and sufficient.Zhao Wei explained that all the reports we have seen are nucleic acid positive. This “nucleic acid positive” does not mean that there must be live virus on the surface of the article.Because when a virus is on a surface, if it stays there for a long time, it loses its vitality.But the nucleic acid of the virus is still present, so there are positive nucleic acid tests on the surface of the object.And if the virus of positive article wants to infect a person, cause a person to appear clinical symptom, want to satisfy at least three conditions: want to have infecting source, that is to say the virus of object surface must be live virus, not the corpse of virus.You have to have the right means of transmission.The virus should enter the body through the correct route of transmission, in the case of the Novel Coronavirus, through the respiratory tract.3. There must be a susceptible population, that is, the person in contact must not be immune. Therefore, only when these three conditions are met at the same time can the contact lead to human infection.Lu Yang) Source: Health Times