Surfaces and Air Contamination by Severe Acute Respiratory Syndrome Coronavirus 2 Using High-Flow Nasal Oxygenation or Assisted Mechanical Ventilation in Intensive Care Unit Rooms of Patients With Coronavirus Disease 2019.

BACKGROUND: Understanding patterns of environmental contamination by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for infection prevention policies. METHODS: We screened surfaces and air samples from single-bed intensive-care unit rooms of adult patients with coronavirus disease 2019 (COVID-19) for SARS-CoV-2 RNA and viable viruses. RESULTS: We evidenced viral RNA environmental contamination in 76% of 100 surfaces samples and in 30% of 40 air samples without any viable virus detection by cell culture assays. No significant differences of viral RNA levels on surfaces and in ambient air were observed between rooms of patients with assisted mechanical ventilation and those of patients with a high-flow nasal cannula system. Using an original experimental SARS-CoV-2 infection model of surfaces, we determined that infectious viruses may have been present on benches within 15 hours before the time of sampling in patient rooms. CONCLUSIONS: We observed that SARS-CoV-2 environmental contamination around patients with COVID-19 hospitalized in single-bed ICU rooms was extensive and that a high-flow nasal cannula system did not generate more viral aerosolization than a mechanical ventilation system in patients with COVID-19. Despite an absence of SARS-CoV-2 viable particles in study samples, our experimental model confirmed the need to apply strict environmental disinfection procedures and classic standard and droplet precautions in ICU wards.

A model for indoor motion dynamics of SARS-CoV-2 as a function of respiratory droplet size and evaporation.

A simplified model has been devised to estimate the falling dynamics of severe acute respiratory syndrome corona-virus 2 (SARS-CoV-2)-laden droplets in an indoor environment. Our estimations were compared to existing literature data. The spread of SARS-CoV-2 is closely coupled to its falling dynamics as a function of respiratory droplet diameter (1 to 2000 µm) of an infected person and droplet evaporation. The falling time of SARS-CoV-2 with a respiratory droplet diameter of about 300 µm from a height of 1.7 m remained almost the same among the Newtonian lift equation, Stokes's law, and our simplified model derived from them so as to account for its evaporation. The evaporative demand peaked at midday which was ten times that at midnight. The evaporating droplets [Formula: see text] 6 µm lost their water content rapidly, making their lifetimes in the air shorter than their falling times. The droplets [Formula: see text] 6 µm were able to evaporate completely and remained in the air for about 5 min as droplet nuclei with SARS-CoV-2.

The Impact of SARS-CoV-2 on Sperm Cryostorage, Theoretical or Real Risk?

Cryopreservation of human gametes and embryos as well as human reproductive tissues has been characterized as an essential process and aspect of assisted reproductive technology (ART). Notably, sperm cryopreservation is a fundamental aspect of cryopreservation in oncological patients or patients undergoing gonadotoxic treatment. Given that there is a risk of contamination or cross-contamination, either theoretical or real, during the procedures of cryopreservation and cryostorage, both the European Society for Human Reproduction and Embryology (ESHRE) and the American Society for Reproductive Medicine (ASRM) have provided updated guidelines for preventing or reducing the contamination risk of sexually transmitted viruses. Given the ongoing and worldwide COVID-19 pandemic, there is considerable interest in what measures should be taken to mitigate SARS-CoV-2 contamination during cryopreservation and cryostorage of semen samples. The SARS-CoV-2 virus is the virus that causes COVID-19, and whose transmission and infection is mainly aerosol-mediated. Several ART professional societies, including ESHRE and ASRM have proposed measures to mitigate the spread of the SARS-CoV-2 virus. Whether the proposed safety directives are enough to mitigate the possible SARS-CoV-2-contamination of sperm samples during cryopreservation or whether the policies should be re-evaluated will be discussed in this review. Additionally, insights regarding the possible impact of COVID-19 vaccination on the safety of sperm cryopreservation will be discussed.