#15,598
Yesterday, in Taiwan Doubles Down On Facemask Wearing Against COVID-19, we looked at the remarkable success in limiting cases and deaths in countries that consistently promoted face covers and/or masks since the start of the pandemic.
Taiwan, with a population of 23 million, has recorded fewer than 700 domestic cases, and only 7 deaths. A rate (per capita) more than 1000 times less than the United States. Hong Kong (6500 cases, 110 deaths), Japan (148K cases, 2139 deaths), and Vietnam (1358 cases, 35 deaths) all have enviable records as well.
Western nations - citing what they felt was a lack of clear evidence of their value, and worried about a meager supply of masks for healthcare workers - were painfully slow to embrace masks for the general public (see HHS's Surgeon General Feb 29th tweet & the World Health Organization's January Guidelines).
But by early April, the CDC had reversed their policy (see The CDC's Cloth Face Cover Recommendations), and soon many other Western nations followed suit. The World Health Organization finally changed their stance in early June (see COVID-19: WHO Changes Face Mask Policy For General Public) with the release of updated guidance.
Since then we've seen a number of studies confirming the value of face covers and public universal masking, including:
CDC Scientific Brief: Community Use of Cloth Masks to Control the Spread of SARS-CoV-2
Two Studies (The Lancet & EID Journal) On The Impact Of NPIs On COVID-19 Spread
The Case For Universal Masking : CDC, MMWR & JAMA
All of which brings us to the first update of the WHO's mask/face cover guidance since June 5th, which further strengthens some of their earlier recommendations. Follow the link to download the full 22-page PDF.
Mask use in the context of COVID-19
Interim guidance
1 December 2020 | COVID-19: Infection prevention and control / WASH
Overview
This document provides updated guidance on mask use in health care and community settings, and during home care for COVID-19 cases. It is intended for policy makers, public health and infection prevention and control professionals, health care managers and health workers.
The Annex provides advice on how to manufacture non-medical masks. It is intended for those making non-medical masks at home and for mask manufacturers.
(EXCERPT)
Mask use in the context of COVID-19
Interim guidance
1 December 2020
This document, which is an update of the guidance published on 5 June 2020, includes new scientific evidence relevant to the use of masks for reducing the spread of SARS-CoV-2, the virus that causes COVID-19, and practical considerations. It contains updated evidence and guidance on the following:
• mask management;
• SARS-CoV-2 transmission;
• masking in health facilities in areas with community, cluster and sporadic transmission;
• mask use by the public in areas with community and cluster transmission;
• alternatives to non-medical masks for the public;
• exhalation valves on respirators and non-medical masks;
• mask use during vigorous intensity physical activity;
• essential parameters to be considered when manufacturing non-medical masks (Annex).
Key points
The World Health Organization (WHO) advises the use of masks as part of a comprehensive package of prevention and control measures to limit the spread of SARS-CoV-2, the virus that causes COVID-19. A mask alone, even when it is used correctly, is insufficient to provide adequate protection or source control.
Other infection prevention and control (IPC) measures include hand hygiene, physical distancing of at least 1 metre, avoidance of touching one’s face, respiratory etiquette, adequate ventilation in indoor settings, testing, contact tracing, quarantine and isolation. Together these measures are critical to prevent human-to-human transmission of SARS-CoV-2.
Depending on the type, masks can be used either for protection of healthy persons or to prevent onward transmission (source control).
WHO continues to advise that anyone suspected or confirmed of having COVID-19 or awaiting viral laboratory test results should wear a medical mask when in the presence of others (this does not apply to those awaiting a test prior to travel).
For any mask type, appropriate use, storage and cleaning or disposal are essential to ensure that they are as effective as possible and to avoid an increased transmission risk.
Mask use in health care settings
• WHO continues to recommend that health workers (1) providing care to suspected or confirmed COVID-19 patients wear the following types of mask/respirator in addition to other personal protective equipment that are part of standard, droplet and contact precautions:
medical mask in the absence of aerosol generating procedures (AGPs)
respirator, N95 or FFP2 or FFP3 standards, or equivalent in care settings for COVID-19 patients where AGPs are performed; these may be used by health workers when providing care to COVID-19 patients in other settings if they are widely available and if costs is not an issue.
In areas of known or suspected community or cluster SARS-CoV-2 transmission WHO advises the following:
- universal masking for all persons (staff, patients, visitors, service providers and others) within the health facility (including primary, secondary and tertiary care levels; outpatient care; and long-term care facilities) wearing of masks by inpatients when physical distancing of at least 1 metre cannot be maintained or when patients are outside of their care areas.
- In areas of known or suspected sporadic SARS-CoV-2 transmission, health workers working in clinical areas where patients are present should continuously wear a medical mask. This is known as targeted continuous medical masking for health workers in clinical areas;
Exhalation valves on respirators are discouraged as they bypass the filtration function for exhaled air by the wearer.
Mask use in community settings
• Decision makers should apply a risk-based approach when considering the use of masks for the general public.
• In areas of known or suspected community or cluster SARS-CoV-2 transmission:
WHO advises that the general public should wear a non-medical mask in indoor (e.g. shops, shared workplaces, schools - see Table 2 for details) or outdoor settings where physical distancing of at least 1 metre cannot be maintained.
If indoors, unless ventilation has been be assessed to be adequate 1 , WHO advises that the general public should wear a non-medical mask, regardless of whether physical distancing of at least 1 metre can be maintained.
Individuals/people with higher risk of severe complications from COVID-19 (individuals > 60 years old and those with underlying conditions such as cardiovascular disease or diabetes mellitus, chronic lung disease, cancer, cerebrovascular disease or immunosuppression) should wear medical masks when physical distancing of at least 1 metre cannot be maintained.
In any transmission scenarios:
Caregivers or those sharing living space with people with suspected or confirmed COVID-19, regardless of symptoms, should wear a medical mask when in the same room.
Mask use in children (2)
Children aged up to five years should not wear masks for source control.
•For children between six and 11 years of age, a risk-based approach should be applied to the decision to use a mask; factors to be considered in the risk-based approach include intensity of SARS-CoV-2 transmission, child’s capacity to comply with the appropriate use of masks and availability of appropriate adult supervision, local social and cultural environment, and specific settings such as households with elderly relatives, or schools.
• Mask use in children and adolescents 12 years or older should follow the same principles as for adults.
• Special considerations are required for immunocompromised children or for paediatric patients with cystic fibrosis or certain other diseases (e.g., cancer), as well as for children of any age with developmental disorders, disabilities or other specific health conditions that might interfere with mask wearing
But when properly worn, and when used as part of a `layered' approach to personal protection (avoiding indoor crowds, good hand hygiene, social distancing, etc.), even cloth masks can help reduce your risk of infection.
Why all of this wasn't obvious to western public health officials years ago remains a mystery to me.
