Research Studies

A cluster randomised trial of cloth masks compared with medical masks in healthcare workers

https://www.researchgate.net/publication/275360639_A_cluster_randomised_trial_of_cloth_masks_compared_with_medical_masks_in_healthcare_workers

The results caution against the use of cloth masks. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection. As a precautionary measure, cloth masks should not be recommended for HCWs, particularly in high-risk situations, and guidelines need to be updated.

Corona children studies “Co-Ki”: First results of a Germany-wide registry on mouth and nose covering (mask) in children

https://assets.researchsquare.com/files/rs-124394/v1/50eb83f9-5a10-44ee-80c4-4de6dd61c6f1.pdf

German registry of parent-reported complaints in children and adolescents caused by wearing a mask, data on over 25k individuals. Average wearing time was 270mins. Impairments caused by mask-wearing were reported by 68% of the parents, including irritability (60%), headache (53%), difficulty concentrating (50%), less happiness (49%), reluctance to go to school/kindergarten (44%), malaise (42%) impaired learning (38%) and drowsiness or fatigue (37%). This suggests that the wearing of face masks does not allow children to be at their best to learn.

Impacts of face coverings on communication: an indirect impact of COVID-19

https://www.tandfonline.com/doi/full/10.1080/14992027.2020.1851401

Face coverings negatively impacted hearing, understanding, engagement, and feelings of connection with the speaker. Impacts were greatest when communicating in medical situations. People with hearing loss were significantly more impacted than those without hearing loss. Face coverings impacted communication content, interpersonal connectedness, and willingness to engage in conversation; they increased anxiety and stress, and made communication fatiguing, frustrating and embarrassing – both as a speaker wearing a face covering, and when listening to someone else who is wearing one.

https://pdmj.org/papers/masks_false_safety_and_real_dangers_part1/

If widespread masking continues, then the potential for inhaling mask fibers and environmental and biological debris continues on a daily basis for hundreds of millions of people. This should be alarming for physicians and epidemiologists knowledgeable in occupational hazards.

Facial protection for healthcare workers during pandemics: a scoping review

https://pubmed.ncbi.nlm.nih.gov/32371574/

The COVID-19 pandemic has led to critical shortages of medical-grade PPE. Alternative forms of facial protection offer inferior protection. More robust evidence is required on different types of medical-grade facial protection. As research on COVID-19 advances, investigators should continue to examine the impact on alternatives of medical-grade facial protection.

Effect of facemasks on empathy and relational continuity: a randomised controlled trial in primary care

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3879648/

Facemasks offer limited protection in preventing infection and aerosol transmission through mucous membranes (i.e. conjunctiva). Meanwhile, a negative impact on the patient’s perceived empathy and relational continuity can reduce potential therapeutic effects such as decreased depression, improved immune response, improved quality of life and improved health outcomes.

Preliminary report on surgical mask induced deoxygenation during major surgery

https://pubmed.ncbi.nlm.nih.gov/18500410/

Considering our findings, pulse rates of the surgeon’s increase and SpO2 decrease after the first hour. This early change in SpO2 may be either due to the facial mask or the operational stress. Since a very small decrease in saturation at this level, reflects a large decrease in PaO2, our findings may have a clinical value for the health workers and the surgeons.

Universal Masking in Hospitals in the Covid-19 Era

https://www.nejm.org/doi/full/10.1056/NEJMp2006372

We know that wearing a mask outside healthcare facilities offers little, if any, protection from infection. Public health authorities define a significant exposure to CoVID-19 as face-to-face contact within 6 feet with a patient with symptomatic CoVID-19 that is sustained for at least a few minutes. The chance of catching CoVID-19 from a passing interaction in a public space is therefore minimal. In many cases, the desire for widespread masking is a reflexive reaction to anxiety over the pandemic.

Effects of wearing N95 and surgical facemasks on heart rate, thermal stress and subjective sensations

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7087880/

It can be concluded that N95 and surgical facemasks can induce significantly different temperatures and humidity in the microclimates of facemasks, which have profound influences on heart rate and thermal stress and subjective perception of discomfort.

Is a Mask That Covers the Mouth and Nose Free from Undesirable Side Effects in Everyday Use and Free of Potential Hazards?

https://www.mdpi.com/1660-4601/18/8/4344/htm

A comprehensive study analysing scientifically proven side effects of wearing masks, spanning psychological and physical deterioration as well as multiple symptoms described because of their consistent, recurrent and uniform presentation from different disciplines as a Mask-Induced Exhaustion Syndrome (MIES).

The authors conclude that “further research is particularly desirable in the gynecological (fetal and embryonic) and pediatric fields, as children are a vulnerable group that would face the longest and, thus, most profound consequences of a potentially risky mask use.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7362770/

This study is an analysis of what has become known as ‘Mask Eye’. Air blowing upward from the mask into eyes likely accelerates the evaporation of the tear film which, with prolonged mask use, may result in ocular surface irritation or inflammation. This together with increasing eye rubbing and face touching due to discomfort from dry eyes create an increased concern for ocular infections secondary to prolonged mask wear. This risk is particularly worrisome during the current pandemic due to a well-documented probability of the novel coronavirus spreading through contact with the eye.

The authors conclude that “further research is particularly desirable in the gynecological (fetal and embryonic) and pediatric fields, as children are a vulnerable group that would face the longest and, thus, most profound consequences of a potentially risky mask use.”

Surgical masks as source of bacterial contamination during operative procedures

https://pubmed.ncbi.nlm.nih.gov/30035033/

The contamination problems of wearing masks for extended periods of time have been known for some time. They were so well known that Chinese doctors in 2018 conducted a study of masks in hospital surgeries to try to come up with guidelines on how to minimize the problem.

Face masks in the general healthy population. Scientific and ethical issues

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7518226/

At present, there is no evidence on the effectiveness of universal masking of healthy people in the community to prevent infection with respiratory viruses, including SARS-CoV-2. Mandatory use of masks in public open spaces, regardless of the risk of transmission or of whether or not the interpersonal safety distance can be kept, is an intrusive measure that restricts individual freedoms, and would not appear to be justified on the basis of available scientific evidence.

Assessment of Proficiency of N95 Mask Donning Among the General Public in Singapore

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2766070

These findings support ongoing recommendations against the use of N95 masks by the general public during the COVID-19 pandemic. N95 mask use by the general public may not translate into effective protection but instead provide false reassurance. Beyond N95 masks, proficiency among the general public in donning surgical masks needs to be assessed.

Use of surgical face masks to reduce the incidence of the common cold among health care workers in Japan: a randomized controlled trial

https://pubmed.ncbi.nlm.nih.gov/19216002/

Face mask use in health care workers has not been demonstrated to provide benefit in terms of cold symptoms or getting colds.

https://onlinelibrary.wiley.com/doi/full/10.1111/dth.13567

Out of 876 participants, only 27 people (3.1%) did not complain of any problems related to face mask-wearing. Out of all reported inconveniences, difficulty in breathing appeared to be the most common one (35.9%), followed by warming/sweating (21.3%), misting up of the glasses (21.3%), and slurred speech (12.3%). Interestingly, other skin bothersome reactions related to wearing of face masks were reported less often (itch–7.7%, skin irritation–0.9%).

Physical interventions to interrupt or reduce the spread of respiratory viruses

https://pubmed.ncbi.nlm.nih.gov/33215698/

There is moderate certainty evidence that wearing a mask probably makes little or no difference to the outcome of laboratory-confirmed influenza compared to not wearing a mask.

https://bmjopen.bmj.com/content/bmjopen/11/2/e044364.full.pdf

A systematic review and meta-analysis of randomised controlled trials and observational studies comparing face mask use to any active intervention or to control.

They concluded that “currently, existing research does not allow firm conclusions as there are insufficient data to quantify all of the adverse effects that might reduce the acceptability, adherence and effectiveness of face masks.” They recommended that “any new research on face masks should assess and report the harms and downsides, including behavioural issues (ie, risk compensation behaviour) and the psychological impact of mandated face mask wear.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7302120/

The use of surgical masks with ear loops in growing children for many hours a day not only leads to intolerance and decubitus of the retroauricular skin (as for adults), but can also influence the correct growth and angulation of the outer ear with the consequent increase in the incidence of protrusion of the outer auricle.

Disposable surgical face masks for preventing surgical wound infection in clean surgery

https://pubmed.ncbi.nlm.nih.gov/27115326/

We included three trials, involving a total of 2106 participants. There was no statistically significant difference in infection rates between the masked and unmasked group in any of the trials.

Aerosol penetration through surgical masks

https://pubmed.ncbi.nlm.nih.gov/1524265/

Although surgical mask media may be adequate to remove bacteria exhaled or expelled by health care workers, they may not be sufficient to remove the submicrometer-size aerosols containing pathogens to which these health care workers are potentially exposed.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7280724/pdf/DTH-9999-na.pdf

Face coverings may also be associated with an increased risk of bacterial skin infections, including impetigo, around the mouth. This may be particularly distressing for children and teenagers, affecting their confidence and self-image.

Use of surgical face masks to reduce the incidence of the common cold among health care workers in Japan: a randomized controlled trial

https://pubmed.ncbi.nlm.nih.gov/19216002/

Face mask use in health care workers has not been demonstrated to provide benefit in terms of cold symptoms or getting colds. A larger study is needed to definitively establish noninferiority of no mask use.

Face masks to prevent transmission of influenza virus: a systematic review

https://www.cambridge.org/core/journals/epidemiology-and-infection/article/facemasks-to-prevent-transmission-of-influenza-virus-a%20systematicreview/64D368496EBDE0AFCC6639CCC9D8BC05

There remains a substantial gap in the scientific literature on the effectiveness of face masks to reduce transmission of influenza virus infection. While there is some experimental evidence that masks should be able to reduce infectiousness under controlled conditions, there is less evidence on whether this translates to effectiveness in natural settings. There is little evidence to support the effectiveness of face masks to reduce the risk of infection.

WHO: Mask use in the context of COVID-19

https://apps.who.int/iris/bitstream/handle/10665/337199/WHO-2019-nCov-IPC_Masks-2020.5-eng.pdf

The potential disadvantages of mask use by healthy people in the general public include:

• headache and/or breathing difficulties, depending on type of mask used;
• development of facial skin lesions, irritant dermatitis or worsening acne, when used frequently for long hours;
• difficulty with communicating clearly, especially for persons who are deaf or have poor hearing or use lip reading;
• discomfort;
• a false sense of security leading to potentially lower adherence to other critical preventive measures such as physical distancing and hand hygiene;
• poor compliance with mask wearing, in particular by young children;
• waste management issues; improper mask disposal leading to increased litter in public places and environmental hazards;
• disadvantages for or difficulty wearing masks, especially for children, developmentally challenged persons, those with mental illness, persons with cognitive impairment, those with asthma or chronic respiratory or breathing problems, those who have had facial trauma or recent oral maxillofacial surgery and those living in hot and humid environments.

The use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence

https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1750-2659.2011.00307.x

There were 17 eligible studies. … None of the studies established a conclusive relationship between mask ⁄ respirator use and protection against influenza infection.

Effectiveness of N95 respirators versus surgical masks in protecting health care workers from acute respiratory infection: a systematic review and meta-analysis

https://www.cmaj.ca/content/188/8/567

We identified 6 clinical studies … In the meta-analysis of the clinical studies, we found no significant difference between N95 respirators and surgical masks in associated risk of a laboratory-confirmed respiratory infection or influenza-like illness.

Effectiveness of Masks and Respirators Against Respiratory Infections in Healthcare Workers: A Systematic Review and Meta-Analysis

https://academic.oup.com/cid/article/65/11/1934/4068747

The confirmed effectiveness of medical masks is crucially important for lower-resource and emergency settings lacking access to N95 respirators. In such cases, single-use medical masks are preferable to cloth masks, for which there is no evidence of protection and which might facilitate transmission of pathogens when used repeatedly without adequate sterilization.

Exercise with facemask; Are we handling a devil’s sword? – A physiological hypothesis

https://pubmed.ncbi.nlm.nih.gov/32590322/

Exercising with facemasks may reduce available Oxygen and increase air trapping preventing substantial carbon dioxide exchange. The hypercapnic hypoxia may potentially increase acidic environment, cardiac overload, anaerobic metabolism and renal overload, which may substantially aggravate the underlying pathology of established chronic diseases.

Adolescents’ face mask usage and contact transmission in novel Coronavirus

https://pubmed.ncbi.nlm.nih.gov/32582579/

Face masks surfaces can become contamination sources. People are storing them in their pockets, bags, putting them on tables, people are reusing them etc.

Do N95 respirators provide 95% protection level against airborne viruses, and how adequate are surgical masks?

https://pubmed.ncbi.nlm.nih.gov/16490606/

The N95 filtering face piece respirators may not provide the expected protection level against small virions. Some surgical masks may let a significant fraction of airborne viruses penetrate through their filters, providing very low protection against aerosolized infectious agents in the size range of 10 to 80 nm. It should be noted that the surgical masks are primarily designed to protect the environment from the wearer, whereas the respirators are supposed to protect the wearer from the environment.

Adolescents’ face mask usage and contact transmission in novel Coronavirus

https://pubmed.ncbi.nlm.nih.gov/32582579/

This study used dye to show if masks were contaminated. “As a result, masks surface become a contamination source. In the contact experiment, ten adults were requested to don and doff a surgical mask while doing a word processing task. The extended contamination areas were recorded and identified by image analysis.”

Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers : A Randomized Controlled Trial

https://pubmed.ncbi.nlm.nih.gov/33205991/

The recommendation to wear surgical masks to supplement other public health measures did not reduce the SARS-CoV-2 infection rate among wearers by more than 50% in a community with modest infection rates, some degree of social distancing, and uncommon general mask use.

Respiratory consequences of N95-type Mask usage in pregnant healthcare workers-a controlled clinical study

https://pubmed.ncbi.nlm.nih.gov/26579222/

Breathing through N95 mask materials have been shown to impede gaseous exchange and impose an additional workload on the metabolic system of pregnant healthcare workers, and this needs to be taken into consideration in guidelines for respirator use. The benefits of using N95 mask to prevent serious emerging infectious diseases should be weighed against potential respiratory consequences associated with extended N95 respirator usage.

Headaches and the N95 face-mask amongst healthcare providers

https://pubmed.ncbi.nlm.nih.gov/16441251/

Of 212 healthcare workers required to wear the medical-grade N95 face mask found that 37% said the mask gave them headaches, and 32% of those people had headaches more than six times a month.

This study looked at health care workers using PPE and their experience of headaches. Whilst wearing PPE “most healthcare workers develop de novo PPE-associated headaches or exacerbation of their pre-existing headache disorders.”

There was a correlation between length of time in PPE and number of headaches and it was recommended to look at “reducing the exposure time by healthcare workers.“

Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings—Personal Protective and Environmental Measures

https://wwwnc.cdc.gov/eid/article/26/5/19-0994_article

There is limited evidence for their effectiveness in preventing influenza virus transmission either when worn by the infected person for source control or when worn by uninfected persons to reduce exposure. Our systematic review found no significant effect of face masks on transmission of laboratory-confirmed influenza.

Respiratory consequences of N95-type Mask usage in pregnant healthcare workers—a controlled clinical study

https://aricjournal.biomedcentral.com/articles/10.1186/s13756-015-0086-z

Breathing through N95 mask materials have been shown to impede gaseous exchange and impose an additional workload on the metabolic system of pregnant healthcare workers, and this needs to be taken into consideration in guidelines for respirator use.

Experimental Assessment of Carbon Dioxide Content in Inhaled Air With or Without Face Masks in Healthy Children

https://jamanetwork.com/journals/jamapediatrics/fullarticle/2781743

This leads in turn to impairments attributable to hypercapnia. A recent review concluded that there was ample evidence for adverse effects of wearing such masks. We suggest that decision-makers weigh the hard evidence produced by these experimental measurements accordingly, which suggest that children should not be forced to wear face masks.