ABSTRACT
The COVID-19 pandemic continues to rage worldwide and the SARS-CoV-2 Omicron variant has now replaced the Delta variant as the leading epidemic strain.Omicron, as one of the SARS-COV-2 variants, incorporates the most critical mutations of the Alpha and Delta variants, and is characterized by having multiple mutation sites, high viral load, stronger infectivity and immune escape, which significantly reduced the protective effect of the vaccine.However, compared with the previous SARS-CoV-2 strains, the Omicron variant is less likely to infect lung tissue, it usually causes mild clinical symptom with reduced hospitalization rate, severe disease rate and fatality rate.Three doses of allogeneic vaccine can offer better tolerance and immunogenicity, and improve the protective effect of the vaccines.The application of small-molecule antiviral drugs and neutralizing antibodies can significantly reduce the hospitalization rate and mortality rate.In this paper, the epidemiological and characteristics of the Omicron variant were reviewed in order to provide reference for clinical diagnosis and treatment of the disease.
ABSTRACT
OBJECTIVE: Currently, coronavirus disease 2019 (COVID-19) has spread worldwide and become a global health concern. Here, we report a familial cluster of six patients infected with severe acute respiratory coronavirus 2 (SARS-CoV-2) in a northern Chinese region and share our local experience with regard the control of COVID-19. METHODS: The demographic data, clinical features, laboratory examinations, and epidemiological characteristics of enrolled cases were collected and analyzed. Two family members (Cases 1 and 2) had Hubei exposure history and were admitted to the hospital with a confirmed diagnosis of COVID-19; eight familial members who had contact with them during the incubation period underwent quarantine in a hospital. We closely followed up all the family members and analyzed their clinical outcome. RESULTS: Case 3 had negative SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR) results but was suspected to have COVID-19 because of radiographic abnormalities. Cases 4 and 5 developed symptomatic COVID-19. Case 6 was considered an asymptomatic carrier as his SARS-CoV-2 RT-PCR result was positive. The other four family members with close contacts to COVID-19 patients had no evidence of SARS-CoV-2 infection. CONCLUSIONS: Our findings suggest that COVID-19 has infectivity during the incubation period and preventive quarantine is effective for controlling an outbreak of COVID-19 infection.