Guidance for the Prevention of the COVID-19 Epidemic in Long-Term Care Facilities: A Short-Term Prospective Study.

BACKGROUND: Guidance aiming at limiting the entry and spread of the COVID-19 have been widely communicated to Long-term Care Facilities (LTCFs). However, no clinical research has investigated their relevance. OBJECTIVE: Our objective was to compare the guidance applied for the prevention of the COVID-19 epidemic between the LTCFs having been contaminated by COVID-19 and LTCFs having not been contaminated. METHODS: A questionnaire was sent and systematically accompanied by phone call to the 132 LTCFs of Haute-Garonne (Occitania region, South-West of France). The questionnaire focused on the preventive measures implemented before March 23, 2020 (first LTCFs contaminated in this area). The questionnaire focused on physician support, implementation of usual guidance (eg, masks, hydro-alcoholic solute used), training on hygiene, containment in residents' rooms and other distancing measures, use of temporary workers, compartmentalization within zones of residents and staff and a self-assessment analogic scale on the quality of the application of the preventive measures. We compared implementation of the guidance between the LTCFs with at least one case of COVID-19 among residents and/or health care professionals and LTCFs without COVID-19 case (between March 23rd and May 6th). RESULTS: 124 LTCFs participated (93.9%). 30 LTCFs (24.19%) were contaminated with COVID-19. Large heterogeneity of the application of the guidance was observed. Public LTCFs (OR= 0.39 (0.20-0.73), LTCFs which organized staff compartmentalization within zones (OR= 0.19 (0.07-0.48)), and LTCF with a staff who self-assessed a higher quality implementation of the preventive measures (OR= 0.65 (0.43-0.98)) were significantly more likely to avoid contamination by the COVID-19 outbreak. CONCLUSION: Our study supports the relevance of guidance to prevent the entry of COVID-19, in particular the staff compartmentalization within zones, as well as the perception of the staff regarding the quality of implementation of those measures in LTCFs.

Dynamic mechanical properties of a biomimetic hydroxyapatite/polyamide 6,9 nanocomposite.

A biomimetic composite of nanohydroxyapatite (nHap) and semicrystalline polyamide 6,9 (PA 6,9) was synthesized by thermally induced phase separation. The nHap powder was dispersed in a polymer matrix with a low ratio ranging 1-10 wt %. The mean size of the nHap, determined by scanning electron microscopy (SEM) was approximately 100-200 nm (length), 40-60 nm (width). Physicochemical analyses were performed in order to characterize the PA 6,9 and nHap separately on the one hand, and the PA 6,9/nHap composites on the other hand. Differential scanning calorimetry (DSC) and dynamic mechanical analyses (DMA) have pointed out an optimization of the composite physical properties as a function of nHap content till a limit value of 5 wt %. Above this value, the mechanical properties decreased. Four main parameters have been found to influence the composite physical properties improvement: the fillers content, the physical structure of the polymeric matrix, the particles dispersion and the physical interaction strength between organic and inorganic phases. The dynamic mechanical properties of this biomimetic nanocomposite were compared with human cortical bone.