Epidemic Risk Assessment by a Novel Communication Station Based Method.

The COVID-19 pandemic has caused serious consequences in the last few months and trying to control it has been the most important objective. With effective prevention and control methods, the epidemic has been gradually under control in some countries and it is essential to ensure safe work resumption in the future. Although some approaches are proposed to measure people's healthy conditions, such as filling health information forms or evaluating people's travel records, they cannot provide a fine-grained assessment of the epidemic risk. In this paper, we propose a novel epidemic risk assessment method based on the granular data collected by the communication stations. We first compute the epidemic risk of these stations in different intervals by combining the number of infected persons and the way they pass through the station. Then, we calculate the personnel risk in different intervals according to the station trajectory of the queried person. This method could assess people's epidemic risk accurately and efficiently. We also conduct extensive simulations and the results verify the effectiveness of the proposed method.

Differences and similarities of occupational risk factors for COVID-19 across waves of the pandemic;extended follow-up of the COVICAT cohort

IntroductionDuring the first pandemic lockdown in Spain certain workers have been at increased risk of COVID-19. Results from published studies are heterogeneous, possibly due to differences in public health interventions, availability of personal protective equipment (PPE), virulence of variants of concern, population-wide immunity or methodological issues.MethodsThe COVICAT study (IEC approved) pooled ongoing population-based cohort studies from Catalonia. Occupational analyses of COVICAT were restricted to working age and included 8,422 participants, of which 3,563 were tested for SARS-CoV-2 antibodies during the first wave;study participants were re-contacted in mid-2021. Participants responded to a web-based or telephone survey including questions on socio-demographics, pre-pandemic health, behavioural and environmental risk factors. Occupational questions covered mode of work, job title, PPE, and mode of commuting. COVID-19 cases were defined by self-reported symptoms or hospitalisation and SARS CoV-2 seropositivity. Association of type of work, job titles and job-exposure matrix (JEM) with COVID-19 was assed using log-binomial models adjusted for potential confounders, such as age, sex, education, deprivation index, population density and survey type. Analyses for the extended follow-up were stratified by pandemic waves.ResultsThe relative risk (RR) for COVID-19 for working at the usual workplace compared to telework was 1.83 (95% CI: 1.41, 2.38), and 1.63 (95% CI: 1.05, 2.52) among the serology study participants. The RR by job title was increased for all health care workers and highest for personal health care workers in health services (6.19;3.71, 10.33);PPE was associated with a stronger protective effect by increasing protection level. Using public transport for commuting was associated with a 50% increase in COVID risk. Results for the extended follow-up will be presented.ConclusionsThe extended follow-up of the COVICAT cohort provides data to illuminate occupational risk factors for COVID-19 infection over time, which may contribute to explain heterogeneities across countries.