Rational use of face masks in the COVID-19 pandemic
It is time for governments and public health agencies to make rational recommendations on appropriate face mask use to complement their recommendations on other preventive measures, such as hand hygiene. WHO currently recommends that people should wear face masks if they have respiratory symptoms or if they are caring for somebody with symptoms? Perhaps it would also be rational to recommend that people in quarantine wear face masks if they need to leave home for any reason, to prevent potential asymptomatic or presymptomatic transmission. In addition, vulnerable populations, such as older adults and those with underlying medical conditions, should wear face masks if available. Universal use of face masks could be considered if supplies permit. In parallel, urgent research on the duration of protection of face masks, the measures to prolong life of disposable masks, and the invention on reusable masks should be encouraged. Taiwan had the foresight to create a large stockpile of face masks; other countries or regions might now consider this as part of future pandemic plans.
Recommendations on face masks vary across countries and we have seen that the use of masks increases substantially once local epidemics begin, including the use of N95 respirators (without any other protective equipment) in community settings. This increase in use of face masks by the general public exacerbates the global supply shortage of face masks, with prices soaring,9 and risks supply constraints to front line health-care professionals. As a response, a few countries (e.g., Germany and South Korea) banned exportation of face masks to priorities local demand.10 WHO called for a 40% increase in the production of protective equipment, including face masks.9 Meanwhile, health authorities should optimist face mask distribution to priorities the needs of front line health-care workers and the most vulnerable populations in communities who are more susceptible to infection and mortality if infected, including older adults (particularly those older than 65 years) and people with underlying health conditions.
Vacuum cleaner bags seem to be particularly good
Vacuum cleaner bags seem to be particularly good at this, according to a 2013 study that compared various household materials based on their ability to filter bacterial and viral aerosols. Tea towels were reasonably effective, but linen and silk performed poorly.
If you do wear a mask, it is important to use it properly. It is easy to contaminate your own mask by touching or reusing it, for example. And don’t let wearing a face mask give you a false sense of security: you can still become infected while wearing one, and washing your hands frequently is vital whether you wear a mask or not.
Even if everyone followed this advice, it isn’t clear whether widespread use of face masks would have a significant impact on the spread of the virus. The WHO says it is collaborating with research and development partners to better understand the effectiveness and efficiency of non-medical masks. There’s just not a lot of evidence for cloth masks in the community, a says McIntyre.