Factors associated with COVID-19 vaccine uptake among French population aged 65 years and older: results from a national online survey.

BACKGROUND: In France, the increase in COVID-19 vaccine uptake among older adults slowed down between May and June 2021. Using the data from a national survey, we aimed to assess COVID-19 vaccine uptake among French residents aged 65 years and older, particularly at risk of severe form of the infection, and identify factors associated with non-vaccination. METHODS: A cross-sectional online survey collected the immunization status/intention to get the COVID-19 vaccine, reasons for vaccination/non-vaccination and factors potentially associated with vaccine uptake between May 10 and 23, 2021 among a large sample of French residents. Characteristics of participants were compared according to immunization status. Factors potentially associated with non-vaccination were computed into a multivariate logistic regression. RESULTS: Among the 1941 survey participants, 1612 (83%) reported having received at least one dose of COVID-19 vaccine. Among the 329 unvaccinated, 197 (60%) declared having the intention to get vaccinated. Younger age (adjusted odds ratio (aOR) = 1.50; 95% confidence interval (CI), 1.05-2.14), thinking previously having COVID-19 (aOR = 4.01; 95% CI, 2.17-7.40), having suffered economic impact due to the pandemic (aOR = 2.63; 95% CI, 1.71-4.04), reporting an "unsafe" opinion about COVID-19 vaccine safety (aOR = 6.79; 95% CI, 4.50-10.26), reporting an "unsupportive" opinion about vaccination in general (aOR = 4.24; 95% CI, 2.77-6.49) were independent risk factors for non-vaccination. On the other hand, trust in COVID-19 vaccine information delivered by the doctor (aOR = 0.28; 95% CI, 0.16-0.48) and trust in the government's actions (aOR = 0.50; 95% CI, 0.34-0.74) were independent protective factors for non-vaccination. Political affiliation also remained significantly associated with vaccine uptake. CONCLUSIONS: Despite high overall COVID-19 vaccine uptake among the study participants, differences in vaccine uptake according to the level of concerns regarding COVID-19 vaccine safety, socioeconomic profile and trust in the government were observed. Our results reinforce the importance of "reaching out" vaccination strategy that specifically targets the most vulnerable fringe of older adult population.

Study of the Pathogen Inactivation Mechanism in Salt-Coated Filters.

As COVID-19 exemplifies, respiratory diseases transmitted through aerosols or droplets are global threats to public health, and respiratory protection measures are essential first lines of infection prevention and control. However, common face masks are single use and can cause cross-infection due to the accumulated infectious pathogens. We developed salt-based formulations to coat membrane fibers to fabricate antimicrobial filters. Here, we report a mechanistic study on salt-induced pathogen inactivation. The salt recrystallization following aerosol exposure was characterized over time on sodium chloride (NaCl), potassium sulfate (K2SO4), and potassium chloride (KCl) powders and coatings, which revealed that NaCl and KCl start to recrystallize within 5 min and K2SO4 within 15 min. The inactivation kinetics observed for the H1N1 influenza virus and Klebsiella pneumoniae matched the salt recrystallization well, which was identified as the main destabilizing mechanism. Additionally, the salt-coated filters were prepared with different methods (with and without a vacuum process), which led to salt coatings with different morphologies for diverse applications. Finally, the salt-coated filters caused a loss of pathogen viability independent of transmission mode (aerosols or droplets), against both DI water and artificial saliva suspensions. Overall, these findings increase our understanding of the salt-recrystallization-based technology to develop highly versatile antimicrobial filters.