ABSTRACT
Aim: To analyze the level of knowledge, attitudes, practices, and risk perception regarding COVID-19 among Chinese residents 1.5 years after the pandemic. Subject and methods: A cross-sectional study was carried out with both online and paper questionnaires. We included a variety of covariates that were characteristic-related factors such as age, gender, education level, and retirement status, as well as those closely associated with risk perception regarding COVID-19. Results: Participants (n = 3588), 53.49 ± 18.88 years old, from two provinces of China, of which 44.7% were male and 52.03% had a high school or greater level of education, answered the questions. More than 90% of participants had adequate background knowledge about COVID-19 and agreed or even strongly agreed with many attitude items related to the government's role in diagnosis, treatment, and dealing with COVID-19 infections. About three fifths of the participants reported fear of contracting COVID-19, but only a minority (18.63%) felt they were more susceptible than others. Respondents aged 45 years or younger were more likely to fear contracting the virus than those older than 45 years (adjusted OR = 1.464, 95% CI 1.196 to 1.794, P = 0.0002). High education level (adjusted OR = 1.503, 95% CI 1.187 to 1.904, P = 0.0007) and non-retired status (adjusted OR = 1.679, 95% CI 1.354 to 2.083, P < 0.0001) were associated with a higher perception of susceptibility to infection than others. Moreover, respondents who were not retired had a significantly reduced practice score (adjusted OR = 1.554, 95% CI 1.261 to 1.916, P < 0.0001). Age, retirement status, and education level were also associated with knowledge, attitude, and practice level. Conclusion: Our findings suggest that the public generally has trust in the COVID-19 vaccine and the government with regard to COVID-19 in China. We recommend that high-risk groups of communities, such as elders and patients with chronic diseases, be given greater consideration in the outbreaks. Health education campaigns combined with workplace preventive intervention should be aimed at improving COVID-19 knowledge and beliefs in order to encourage more optimistic attitudes and to maintain safe practices.
ABSTRACT
Limited data are available on the effectiveness of COVID-19 vaccines used in China in real-world outbreaks - especially against Omicron variants in vaccinated individuals. Two outbreaks of SARS-CoV-2 Omicron variants - the first involving the sub-lineage BA.2 and the second the BA.1 variant - occurred in Quzhou. Infected people and their close contacts were divided according to vaccination status: unvaccinated, partially vaccinated, fully vaccinated, and boosted. The Cox proportional-hazard regression model was used to estimate the evolving hazard for vaccinated individuals after their first immunization. 138 people had been infected with the SARS-CoV-2 Omicron BA.2 variant and 13 with the BA.1 variant. Of the 151 infections, 99.34% (150/151) were mild or asymptomatic and 90.07% (136/151) were vaccine breakthrough cases. The total vaccine effectiveness (VE) of partial, full, and booster vaccinations during the two outbreaks was 47.4% (95%CI: 0-93.1%), 28.9% (95%CI: 0-60.2%), and 27.5% (95%CI: 0-58.3%). The VE of booster vaccination against the Omicron BA.1 variant was higher than that for the BA.2 variant. The cumulative hazard began to increase 220 days after the first immunization. The transmissibility of the Omicron BA.2 variant as for BA.1 did not increase in vaccinated individuals; booster vaccination after a primary course substantially increased protection. Our study found that the SARS-CoV-2 Omicron variant caused less severe illness and that the VE of boosters against the Omicron variant was less than 30%. Timely administration of the booster dose was important, especially for individuals aged over 80 years old.