What is required to prevent a second major outbreak of the novel coronavirus SARS-CoV-2 upon lifting the metropolitan-wide quarantine of Wuhan city, China

BackgroundThe Chinese government implemented a metropolitan-wide quarantine of Wuhan city on 23rd January 2020 to curb the epidemic of the coronavirus COVID-19. Lifting of this quarantine is imminent. We modelled the effects of two key health interventions on the epidemic when the quarantine is lifted. MethodWe constructed a compartmental dynamic model to forecast the trend of the COVID-19 epidemic at different quarantine lifting dates and investigated the impact of different rates of public contact and facial mask usage on the epidemic. ResultsWe estimated that at the end of the epidemic, a total of 65,572 (46,156-95,264) individuals would be infected by the virus, among which 16,144 (14,422-23,447, 24.6%) would be infected through public contacts, 45,795 (32,390-66,395, 69.7%) through household contact, 3,633 (2,344-5,865, 5.5%) through hospital contacts (including 783 (553-1,134) non-COVID-19 patients and 2,850 (1,801-4,981) medical staff members). A total of 3,262 (1,592-6,470) would die of COVID-19 related pneumonia in Wuhan. For an early lifting date (21st March), facial mask needed to be sustained at a relatively high rate ([≥]85%) if public contacts were to recover to 100% of the pre-quarantine level. In contrast, lifting the quarantine on 18th April allowed public person-to-person contact adjusted back to the pre-quarantine level with a substantially lower level of facial mask usage (75%). However, a low facial mask usage (<50%) combined with an increased public contact (>100%) would always lead a significant second outbreak in most quarantine lifting scenarios. Lifting the quarantine on 25th April would ensure a smooth decline of the epidemics regardless of the combinations of public contact rates and facial mask usage. ConclusionThe prevention of a second epidemic is viable after the metropolitan-wide quarantine is lifted but requires a sustaining high facial mask usage and a low public contact rate.

Study of the association between interleukin-1 polymorphisms and genetic susceptibility of coal workers’ pneumoconiosis and silicosis / 中华劳动卫生职业病杂志

Objective@#To evaluate the relationship between IL-1 gene polymorphisms and coal workers’ pneumoconiosis and silicosis susceptibility.@*Methods@#We searched published full-text from PubMed, Web of Science, CNKI, VIP and Wanfang to collect case-control study on IL-1 gene polymorphisms with coal workers’ pneumoconiosis and silicosis susceptibility. Eight articles, including 10 case-control studies were included in our study. All analyses were performed using the Stata version 12.0 software.@*Results@#The IL-1RA (+2018) TC or CC variant genotypes were associated with coal workers’ pneumoconiosis and silicosis risk (OR=1.65, 95%CI: 1.11-2.46) . In further stratified analyses, the IL-1RA (+2018) TC or CC variant genotypes were associated with an increased silicosis risk (OR=2.07, 95%CI: 1.45-2.95) , which were also associated with increased coal workers’ pneumoconiosis and silicosis risk in Caucasians (OR=1.74, 95%CI: 1.22-2.47) . No significant association between IL-1β (+3953) , IL-1β (-511) , IL-1α (+4845) and coal workers' pneumoconiosis and silicosis risk was found either in the overall study or in the stratified analysis.@*Conclusion@#These findings suggested that IL-1RA (+2018) may modify coal workers’ pneumoconiosis and silicosis susceptibility. Further replication studies with large sample sizes are warranted to re-evaluate the relationship between IL-1RA (+2018) and coal workers’ pneumoconiosis and silicosis risk.