Covid Shorts: Why wearing masks properly can save your life

 

We are constantly being told to wear a mask when we go out or are among a crowd. We are issued a fine if caught without a mask in public places.

But wearing a mask is not enough. It must fit properly on the face or we risk infection, says a new study by the University of Cincinnati (UC).

Poorly fitted face masks can even double the infection risk to the wearers and people around them, researchers in UC’s College of Engineering and Applied Science say in the study published in the Nature journal Scientific Reports.

The researchers used computerised tomography or CT scans of three different-sized face masks attached to three different-sized dummy heads to measure the gaps between the face and the fabric. Then they calculated the leaks from these gaps to determine the infection risk.

They found that while N95 masks were effective barriers against Covid-19 and other airborne diseases, poorly fitting masks could have substantial leaks around the face that reduced their effectiveness and increased the risk of infection.

“Many people do not realise that the fit of face masks can vary. There are different face shapes and different sizes of masks,” says Rupak Banerjee, a professor in UC’s Department of Mechanical and Materials Engineering. “If you do not match them well, it can lead to greater leaks and higher risks of infection,” he adds.

The researchers, led by Prasanna Hariharan of the US Food and Drug Administration’s Division of Applied Mechanics, found that aerosol transport attributed to leaking out the sides of the masks varied from as little as 30% to as much as 95% for the worst-fitting masks.

The leaks were most often around the nose.

What is the takeaway for us? Masks are effective in helping keep us safe but their effectiveness depends on the fit of the mask and how properly we wear them. It is no use just going out with any mask, we must check to see that it is worn in such a manner that it fits as well as possible on our face.

I suppose that is why health director-general Dr Noor Hisham Abdullah recently advised Malaysians to wear two masks. He said wearing a cloth mask on top of a medical-grade mask would help filter more particles than wearing a cloth mask alone. But if you are wearing the N95 mask, you don’t have to worry about double-masking. The problem, however, is getting a N95 mask at our pharmacies, so most of us will have to do with lesser quality masks.

With daily infections still high, hovering around 5,000 cases or more, it is important that all of us take this seriously. Remember, the vaccines reduce the severity of infection but it is the mask, physical distancing and hand hygiene which help prevent us from getting infected.

Beware of speech droplets

The importance of masks has been hammered home again by a another new study published in the Journal of Internal Medicine which shows that unmasked speech in confined spaces poses the greatest risk of spreading SARS-CoV-2 to others.

When we speak, thousands of droplets are emitted which can’t be seen by the naked eye. “When the water evaporates from such speech-generated, potentially virus-rich droplets, they float in the air for minutes, like smoke, thus putting others at risk,” says senior author of the study Adriaan Bax of the US National Institute of Diabetes and Digestive and Kidney Diseases.

According to the study, respiratory droplets emitted while speaking come in a variety of sizes and can carry different amounts of the virus. Of most concern are intermediate-sized droplets that remain suspended in the air for minutes and can be transported over considerable distances by convective air currents.

This study is supported by another done by researchers from Stony Brook University, Harvard, ETH Zurich, and Hanyang University.

They show that normal breathing indoors without a mask can transport saliva droplets capable of carrying virus particles to a distance of 2.2 metres in a matter of 90 seconds.

The use of a face mask, they say, significantly reduces the distance these droplets travel. After almost two minutes, the saliva droplets restricted by a mask had travelled only 0.72 metres.

Common cold can stop Covid-19 virus?

Don’t fret if you catch the common cold. It might just be what the doctor ordered in this time of the Covid-19 pandemic.

Researchers at Yale University have found that exposure to the rhinovirus, the most frequent cause of the common cold, can protect against infection by the SARS-CoV-2 virus which causes Covid-19.

The common respiratory virus, they report in the June 15 Journal of Experimental Medicine, jump-starts the activity of interferon-stimulated genes – early-response molecules in the immune system – which can halt replication of the SARS-CoV-2 virus within airway tissues infected with the cold.

According to Ellen Foxman, assistant professor of laboratory medicine and immunobiology at the Yale School of Medicine and senior author of the study, triggering these defenses early in the course of Covid-19 infection could prevent or treat the infection.

One way to do this is by treating patients with interferons, an immune system protein which is also available as a drug. “But it all depends upon the timing,” Foxman says.

However, we have to wait and see how this develops. So, please don’t get wet in the rain hoping to catch a cold just yet.

Covid-19 reinfection rate

Research by the University of Missouri School of Medicine and MU Health Care shows less than 1% of 9,119 patients in the US with severe Covid-19 contracted the disease again.

Researchers found 63 of the 9,119 patients (0.7%) with severe Covid-19 infection contracted the virus a second time. The mean reinfection period was 116 days. Of the 63 who were reinfected, two (3.2%) died.

Lead researcher Adnan I Qureshi, a professor of clinical neurology at the MU School of Medicine says: “Our analysis also found asthma and nicotine dependence were associated with reinfection. However, there was a significantly lower rate of pneumonia, heart failure and acute kidney injury observed with reinfection compared with primary infection.”

The duration of immunity that an initial infection provides is not completely clear, says Qureshi.

The lesson for us: Reinfection of Covid-19 is possible, even though only a small number may contract the disease a second time. Those who have asthma have to take extra precautions and those who smoke -already in danger of getting all manner of diseases – should throw the habit into the drain.

Heart health and Covid-19

Heart disease, diabetes, high blood pressure and obesity may double the odds of dying from Covid-19, according to a study published in the European Heart Journal-Quality of Care and Clinical Outcomes.

Researchers found that factors associated with a higher likelihood of worse outcomes from Covid-19 were high blood pressure, current or past smoking, obesity, diabetes, previous stroke or pre-existing cardiovascular disease, liver disease, and kidney disease.

The study, commissioned by Public Health England, found heart disease was linked to a nearly four-fold odds of severe Covid-19, while the odds were more than double for hypertension and diabetes, and 80% higher in smokers compared with non-smokers.

The researchers note that as the research was based on observational studies, it suggests relationships but cannot confirm causality.

What is clear from this study is that heart health is important. How do we keep the heart healthy? Here are some tips from the Mayo Clinic:

• Get moving: Aim for at least 30 to 60 minutes of activity daily;
• Don’t smoke or use tobacco;
• Eat healthy: more vegetables, fruits, legumes, and healthy fats but less salt, sugar, processed carbohydrates, alcohol, and saturated and trans fats;
• Get good quality sleep;
• Maintain a healthy weight;
• Manage stress; and
• Get regular health screenings

- FMT

The views expressed are those of the writer and do not necessarily reflect those of MMKtT,