Reuters reported in reference news on the 11th that "large scale research has found that the toxicity of Omicron mutant is as strong as that of the previous novel coronavirus mutant". The summary of the report is as follows: A large study in the United States found that the toxicity of the Omicron variant of novel coronavirus is essentially as strong as that of previous variants. Previous studies have hypothesized that the Omicron variant is more infectious but less toxic. Four scientists conducted the study based on the medical records of 130000 patients with new crowns. "We found that the risk of hospitalization and death was almost the same in different periods," they said They refer to the various periods in the past two years when different novel coronavirus variants have successively become the world's mainstream strains. The research report is being peer-reviewed on the website of nature journals and services collection in the UK and was published on the website of research square in the United States on May 2. The study included a number of confounding factors, including population structure, vaccination status and the "Charlson comorbidity index". The "Charlson comorbidity index" can be used to predict the risk of death within one year of hospitalization for patients with specific comorbidities. These scientists from Massachusetts General Hospital, minawa University and Harvard University School of Medicine said that previous studies that assumed that the Omicron variant was less toxic were carried out in South Africa, Scotland and England in the UK, as well as Canada. These scientists also said that their research may have some limitations, including that they may underestimate the number of vaccinated infected people and the total number of infected people in recent waves of COVID-19, because it does not include those patients who receive rapid testing at home. (Xinhua News Agency)