Скачать или смотреть Part 2: Coping with COVID-19 for running IVF Lab: Air Quality - PPE - D. Niveen Shaker MSC

It is mandatory that IVF laboratory staff follow a rigorous protocol for the maintenance of hand hygiene by regular washing with soap and water before entering the laboratory, after encountering patients, and after removal of gloves. All staff members including the laboratory team and health care-workers must use a proper set of personal protective equipment (PPE) including disposable laboratory coats, gloves, cap, eye protectors, shoe covers, and face mask, during working hours, and wear a face mask everywhere outside the facility as SARS-CoV-2 is airborne (De Santis et al., 2020; Leung et al., 2020; Xiao and Torok, 2020). Members using contact lenses must replace them with prescription glasses to reduce the risk of touching their eyes. All used PPE must be properly discarded in biosafety containers.

IVF laboratories are equipped with high-efficiency particulate air (HEPA) filtration, and filters to remove volatile organic compounds (VOCs) under positive pressure, providing healthier conditions for embryo development (Mortimer et al., 2018). This system is fitted and harmonized with heating, ventilation, and air conditioning (HVAC) system (Mortimer et al., 2018). However, the airborne transmission of COVID-19 can be prompted by HVAC (Lu et al., 2020), which if combined with the aerosolization pattern of SARS-CoV-2 could suggest HVAC systems as a potential source for COVID-19 transmission (DUAN Wei, 2012; Lu et al., 2020). Thus, although strange, it is plausible that switching off HVAC systems along with all other direct or indirect airflow including the workstations during the working hours to minimize the risk of susceptible infection with COVID-19 appears safer.
HEPA filters can only be 99.97% efficient at capturing particles larger than approx. 0.3µm in diameter, suggesting that HEPA filters cannot provide adequate protection against SARS-CoV-2 which is 70–90 nm in size (Kim et al., 2020). However, photocatalytic purification systems could theoretically disrupt the integrity of the virus, although no evidence exists. Thus, despite being critical for the maintenance of laboratory air quality, using more HEPA filters or air purifiers has no role in protection against SARS-CoV-2. The opposite can theoretically be true as they could push a high viral load into certain areas of the laboratory depending upon their airflow direction.
A standard recommendation for an IVF laboratory is to maintain positive pressure (Mortimer et al., 2018). However, the COVID-19 pandemic appears to challenge most of these dogmas to reduce the risk of transmitting this deadly virus and the positive pressure in the IVF laboratory is no exception. Operating theatres, intensive care units, and hospitals for COVID-19 patients in isolation use negative pressure as standard to reduce the viral load (Chow et al., 2006). Although positive pressure with adequate air changes per hour carries a low risk for cross-contamination for adequately protected staff with PPE (Seto et al., 2003), whether the negative pressure can be applied safely in the IVF setting for higher protection to personnel remains an open question.