Epidemic of the SARS-CoV-2 Omicron variant in Shanghai, China in 2022: Transient and persistent effects on Out-of-hospital cardiac arrests.

OBJECTIVE: To investigate transient and persistent effects of the Shanghai Omicron epidemic in 2022 on the incidence, characteristics, and outcomes of out-of-hospital cardiac arrest (OHCA). METHODS: This retrospective study examined electronic records of patients admitted to the Shanghai Emergency Medical Center during five periods: pre-epidemic, 1 January 2018 to 31 December 2019; low COVID-19 incidence, 1 January 2020 to 27 March 2022; Omicron epidemic, 28 March to 31 May 2022; early post-epidemic, 1 June to 31 July 2022; and late post-epidemic, 1 August to 30 September 2022. Clinicodemographic characteristics and outcomes of OHCA cases were compared between the pre-epidemic and other periods. RESULTS: A total of 55,104 OHCAs were included. The monthly number of OHCAs in the Omicron epidemic was 2.1 times the number in the pre-epidemic (1702 vs 793), while the number in the early post-epidemic was 1.9 times the number in the pre-epidemic (1515 vs 793). Compared to the pre-epidemic, OHCA during or after the epidemic was more likely to involve individuals with hypertension, coronary artery disease, heart failure or stroke. The probability that circulation would spontaneously resume after OHCA was significantly lower during the epidemic than before it (aOR 0.61, 95% CI 0.41-0.90; P = 0.012). However, this difference disappeared by the early post-epidemic. CONCLUSION: The monthly number of OHCAs doubled during the Omicron epidemic in Shanghai, and it remained elevated for another two months. OHCA affected individuals with cardiovascular and cerebrovascular diseases more during and after the epidemic than before it.

A Multicentre Study on the Prevalence of Respiratory Viruses in Children with Community Acquired Pneumonia Requiring Hospitalization in the Setting of the Zero-COVID Policy in China (preprint)

Stringent nonpharmaceutical interventions (NPIs) have been implemented worldwide to combat the COVID-19 pandemic, and the circulation and seasonality of common respiratory viruses have subsequently changed. Multicentre studies and comparisons of the prevalence of respiratory viruses accounting for community-acquired pneumonia (CAP) in hospitalized children between the pre-COVID period and the period after community and school reopening in the setting of the zero-COVID policy are rare. In this study, we included 1543 children with CAP who required hospitalization from November 1st, 2020 to April 30th, 2021 (Period 1) and 629 children with the same conditions from November 1st, 2018 to April 30th, 2019 (Period 2) in our study. All respiratory samples from the included patients were screened for six respiratory viruses (respiratory syncytial virus [RSV], adenovirus [ADV], influenza A virus [Flu A], influenza B virus [Flu B], parainfluenza virus type 1 [PIV1], and parainfluenza virus type 3 [PIV3]) using a multiplex real-time PCR assay. The median ages of enrolled patients at the time of diagnosis were 1.5 years and 1.0 years for period 1 and period 2, respectively. In period 1, viral pathogens were detected in 50.3% (776/1543) of enrolled patients. The most frequently identified viral pathogen was RSV (35.9%, 554/1543), followed by PIV3 (9.6%, 148/1543), PIV1 (3.6%, 56/1543), ADV (3.4%, 52/1543), Flu A (1.0%, 16/1543) and Flu B (0.8%, 13/1543). The total detection rates of these six viruses in the peak season of CAP were at the pre-COVID level. The prevalence of Flu A decreased dramatically and circulation activity was low compared to pre-COVID levels, while the incidence of PIV3 increased significantly. There were no significant differences in the detection rates of RSV, ADV, Flu B and PIV1 between the two periods. Our results showed that respiratory viruses accounted for CAP in hospitalized children at pre-COVID levels as communities and schools reopened within the zero-COVID policy, although the prevalence aetiology spectrum varied.