Covid-19 vaccine effectiveness during Omicron BA.2 pandemic in Shanghai: A cross-sectional study based on EMR.

Large-scale vaccination against the spread and mutation of COVID-19 is being implemented in many countries. We aimed to assess the effectiveness of certain vaccines (87.35% inactivated), mainly Sinovac - CoronaVac and Sinopharm (Beijing) - BBIBP-CorV, during the Omicron BA.2 pandemic by cross-sectional study. The study was conducted in a cabin hospital of Shanghai, China. A total of 1194 Covid-19 patients infected with Omicron BA.2 were enrolled and epidemiological survey information was collected from the subjects through electronic medical records and questionnaires, from March 23th to April 1st in 2022. Vaccine effectiveness was reflected by the occurrence of multi-dimensional symptoms while adjusting for confounding variables. In the unstandardized vaccinated group, the Covid-19 vaccine effectiveness of Omicron BA.2 in the male group was higher than in the female group (P = .0171). In the standardized vaccinated group, vaccine effectiveness in [20, 40) age group was higher than in other age groups (P = .0002). Adjusting for gender and age, Covid-19 vaccine effectiveness of Omicron BA.2 at the specific level was 87.42% (95% confidence interval [CI], 72.35-94.28, P < .0001), and 62.65% (95% CI, 1.47-85.84, P = .047) in the unstandardized vaccinated and the standardized vaccinated group, respectively. Covid-19 vaccine effectiveness of Omicron BA.2 was not apparent at the general level but remained effective for the specific symptom. Further development for the Covid-19 vaccine is necessary.

Achieving Universal Wearing of Face Masks During the COVID-19 Pandemic: A Practical Solution from Shanghai, China.

BACKGROUND: Face masks are basic protective equipment for preventing respiratory infectious diseases. The measures to properly dispose of and allocate face masks during the early stage of an epidemic caused by respiratory infectious diseases deserve worldwide attention. METHODS: A qualitative research approach was used to document the practice of a citywide face mask-wearing strategy of the Shanghai Municipal Government (called the "Shanghai solution" in this article). Based on data from government work documents, an online face mask-allocation and sales system was built to offer real-time updates of face-mask appointments and sales information in all designated pharmacies and neighborhood committees in Shanghai. RESULTS: In the Shanghai solution, a total of 24.8 million residents in 6,031 committees were covered, in order to achieve universal wearing of face masks during the COVID-19 crisis. Up to 110 million face masks were dispensed to residents in six rounds of face-mask allocation during February to April. This practical experience in Shanghai solved two key problems (insufficient face-mask capacity, protection of vulnerable population) with the supply of face masks by addressing four essential characteristics: overall coordination, on-demand distribution, efficient distribution, and technical support. CONCLUSION: The practice of the citywide face mask-supply strategy of Shanghai could provide several pointers for management of a shortage of emergency materials, dispatch, and transport to other countries during the pandemic.