What is the Best Face Mask for Coronavirus?
As the novel coronavirus (COVID-19) has spread, demand for protective gear has skyrocketed. News of the pandemic continues to dominate the media’s top headlines and occupy the world’s attention.
Here we’ll break down the best face masks to keep on hand during the coronavirus and attempt to demystify the contradictory advice out there.
- Current Understanding of COVID-19
- Recommended Guidelines for Faces Masks During Coronavirus
- Common Types of Face Masks
- Mask Effectiveness Against COVID-19 Infection: The Scientific Research
- Why We Should All Wear Masks
- The Takeaways on Face Mask Usage
- Bottom Line: Do Face Masks Help Protect Against Coronavirus?
Face masks have become one of the more controversial topics related to Coronavirus. Some are claiming that masks are useless in preventing COVID-19, while others are even putting pet masks on their cats and dogs!
So, what does science say about wearing masks for the coronavirus? Are they protective, and if so, which type?
Current Understanding of COVID-19
COVID-19 belongs to a family of airborne respiratory viruses that are transmitted among people in a similar fashion to flu.
When an infected person coughs, sneezes, laughs or talks, people nearby can inhale the virus particles.
While seasonal flu can be prevented using vaccine-based interventions, COVID-19 is a completely new challenge to humanity.
“In an emerging outbreak of infectious disease, non-pharmaceutical measures including facemasks and respirators may be the only available protection.”¹Raina MacIntyre, Infectious Diseases Epidemiology Professor & Scientist
Recommended Guidelines for Faces Masks During Coronavirus
Country leaders and government officials now advocate the use of face masks for the general population when out in public.
Previously, both the WHO and CDC did not recommend community members who are well to wear masks. They warned the public that wearing masks may subconsciously make you touch you faces more often, increasing risk of infection. But this issue wasn’t without controversy online.
If you are without a mask, consider making your own. Any form of protection is better than none. But which is the best face mask for coronavirus?
Let’s first explore the different types of masks.
Common Types of Face Masks
1. Cloth Face Masks
Cloth masks are common in Asian countries, which can be washed and reused.
A randomised control trial compared the efficacy of cloth masks to medical masks in 1607 hospital workers.²
The results suggest that the risk of infection is significantly higher in the cloth masks group, with a shocking particle penetration rate of 97%. In contrast, the penetration rate for surgical masks is 44%.
The researchers warned that cloth masks may even be harmful as they retain moisture and act as a breeding ground for pathogens.
2. Surgical Face Mask
Surgical masks are loose-fitting rectangles that cover the mouth and nose.
They were initially meant to protect patients during sterile procedures from cough and secretions by their healthcare practitioners, including doctors and nurses.
3. N95 Respirator Mask
N95 respirators are specialized masks that can filter out more than 95% of very small (0.3 micron) airborne particles, including viruses. They are thicker and have a tighter fit than surgical masks.
However, breathing is more difficult in N95 respirators and not everyone is able to wear them. Fit-testing and training are required to ensure safety.
Mask Effectiveness Against COVID-19 Infection: The Scientific Research
A number of studies have examined the efficacy of face mask use in preventing respiratory infections. These studies have shown vastly mixed results.
A randomized trial conducted in 68 Chinese emergency departments and respiratory wards compared the effects of wearing a surgical mask at all times, an N95 respirator at all times and an N95 respirator only during high-risk procedures.³
The results? Those who wore N95 respirators at all times had the lowest rates of respiratory infections compared to those who wore them part time or wore surgical masks. Nevertheless, the infection rates of all groups were lower when compared to no-mask group, indicating wearing either surgical masks or N95 respirators is more effective than wearing no mask at all.
The same leading researcher conducted another randomized trial in households, comparing parents who wore no masks, surgical masks or N95 respirators when taking care of children with respiratory illnesses.⁴
It turns out that the adherence to using face masks resulted in lower infection rates compared to not wearing a mask at all. However, surgical masks and N95 respirators were similarly effective.
Another study of 617 households in America randomized participants into three groups:
- Education only
- Hand sanitizer
- Hand sanitizer + Medical masks.⁵
The result? The rates of respiratory infections were lower in the hand sanitizers and hand sanitizer plus medical masks groups.
Although these differences were not statistically significant, the hand sanitizer + medical masks group had significantly reduced rate of later secondary influenza attack. Therefore, it appears that wearing masks could be effective for preventing influenza-like infections like COVID-19, and government bodies are now suggesting their usage.
Some Conflicting Results?
It’s important to note that there are also several studies that showed no significant difference between surgical masks, N95 respirators or wearing no mask at all. These results are seemingly contradictory to the above studies that showed effective outcomes of wearing face masks.⁵⁻¹⁰
Why We Should All Wear Masks
- Preventive surgical masks in the community may slow down a pandemic when implemented early and worn appropriately with good compliance.
- Having infected patients wear masks (source control) is more effective than preventative mask wearing. N95 respirators are likely the most protective for trained healthcare workers, but not community members.
- Cloth masks are not recommended and may even be harmful.
- Wearing masks alone is unlikely to be sufficient and should be coupled with other hand washing and social distancing measures.
The Takeaways on Face Mask Usage
1. Compliance to Mask Wearing is Poor
In one study, people who practiced good adherence experienced significantly reduced risk for influenza-like infection. However, less than 50% of the participants wore masks most of the time.⁴
Similarly, in a study that reported no significant effect of using face masks to prevent influenza, only around 50% of participants wore masks “mostly” or “always”.⁸ Therefore, non-significant results must be interpreted knowing that subject compliance is low.
Masks work, the problem is that getting the public to adhere to adhere to their usage is the more difficult challenge.
2. Mask Usage Must Be Done Early and Often
Wearing a mask early on in an influenza season showed significant reduction in the infection rate, although the results did not reach statistical significance over the whole length of study.⁷
Similarly, two studies showed that household transmission of influence could be reduced by using face masks, but only when the intervention was implemented within 36 hours after the onset of an infected case in the family.⁶⁸ Therefore, the timing of face mask use is also a determinant of preventative outcome.
For effective prevention of the spread of a virus like the coronavirus, masks must be worn by the population early and always.
3. Face Masks are More Effective When Used on Infected People
One study in 2016 tested the ability to control airborne infection by using various types of face masks on either the infectious source or a receiver.¹¹
In other words, the researchers wanted to know: is it better to control the already infected, or to protect someone potentially receiving the infection?
The results indicated that putting a face mask on the infectious source could control outward leakage of infectious particles. Fewer infections resulted when either surgical masks or N95 respirators were were worn compared to not.
4. N95 Respirators May be Better at Protecting High-Risk Healthcare Workers
A review of 67 studies published in 2011 concluded that N95 respirators are as effective as surgical masks, only more expensive, uncomfortable and irritating.¹²
However, a more recent review in 2015 concluded that healthcare workers are more protected by respirators compared to surgical masks, especially when the disease is severe, lethal and no treatment or vaccine is available.¹ The COVID-19 pandemic fulfils these criteria.
But, officials warn that protection is only provided with compliance and appropriate mask use. This can most likely be ensured in a healthcare setting.
For community residents who are in a low-risk household setting and have no access to appropriate training, the protectional capabilities of N95 masks are likely diminished.
Bottom Line: Do Face Masks Help Protect Against Coronavirus?
Yes. Face masks can be protective during pandemics such as the coronavirus, but this is subject to diligent early use.
The best face mask for coronavirus is really any mask that you have access to. Any mask provides more protection than none, though do keep in mind that some studies have shown cotton mask usage may be counterproductive.
However, wearing masks alone is unlikely to be sufficient and should be coupled with other hand washing and social distancing measures.
For detailed information, see these websites:
- Occupational Safety and Health Administration: COVID-19
- Centers for Disease Control and Prevention – Coronavirus
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