Coronavirus Technology Solutions
November 12, 2020

Efforts Needed to Reduce Risk of COVID Evolving  to Resist Vaccines

UK Mask Production Cleanroom Built on Accelerated Schedule

Comfort and Appearance Important for Child Masks

Mask Cleaning and Disposal should be as Frequent as Stepping on a Foot Sanitizer

Mask Choices for the Pandemic

Media Starting to Analyze Mask Fit and Its Importance

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Efforts Needed to Reduce Risk of COVID Evolving  to Resist Vaccines 

Similar to bacteria evolving resistance to antibiotics, viruses can evolve resistance to vaccines, and the evolution of SARS-CoV-2 could undermine the effectiveness of vaccines that are currently under development, according to a paper published in the open-access journal PLOS Biology by David Kennedy and Andrew Read from Penn State University. The authors also offer recommendations to vaccine developers for minimizing the likelihood of this outcome.

"A COVID-19 vaccine is urgently needed to save lives and help society return to its pre-pandemic normal," said Kennedy, assistant professor of biology. "As we have seen with other diseases, such as pneumonia, the evolution of resistance can quickly render vaccines ineffective. By learning from these previous challenges and by implementing this knowledge during vaccine design, we may be able to maximize the long-term impact of COVID-19 vaccines."

The researchers specifically suggest that the standard blood and nasal-swab samples taken during clinical trials to quantify individuals' responses to vaccination may also be used to assess the likelihood that the vaccines being tested will drive resistance evolution. For example, the team proposes that blood samples can be used to assess the redundancy of immune protection generated by candidate vaccines by measuring the types and amounts of antibodies and T-cells that are present.

"Much like how combination antibiotic therapy delays the evolution of antibiotic resistance, vaccines that are designed to induce a redundant immune response—or one in which the immune system is encouraged to target multiple sites, called epitopes—on the virus's surface, can delay the evolution of vaccine resistance," said Andrew Read, Evan Pugh Professor of Biology and Entomology and director of the Huck Institutes of the Life Sciences. "That's because the virus would have to acquire several mutations, as opposed to just one, in order to survive the host immune system's attack."

The researchers also recommend that nasal swabs typically collected during clinical trials may be used to determine the viral titer, or amount of virus present, which can be considered a proxy for transmission potential. They noted that strongly suppressing virus transmission through vaccinated hosts is key to slowing the evolution of resistance, since it minimizes opportunities for mutations to arise and reduces opportunities for natural selection to act on those mutations that do arise.

In addition, the team suggests that the genetic data acquired through nasal swabs can be used to examine whether vaccine-driven selection has occurred. For example, differences in alleles, or forms of genes that arise from mutations, between the viral genomes collected from vaccinated versus unvaccinated individuals would indicate that selection has taken place.

"According to the World Health Organization, at least 198 COVID-19 vaccines are in the development pipeline, with 44 currently undergoing clinical evaluation," said Kennedy. "We suggest that the risk of resistance be used to prioritize investment among otherwise similarly promising vaccine candidates."

UK Mask Production Cleanroom Built on Accelerated Schedule

The COVID-19 pandemic and the new government advice/rules on mandatory face coverings has seen a huge rise in demand for face masks. But how can the UK government satisfy such a large and sustained increase in demand without impacting on the supply of face masks for the countries front-line National Health Service (NHS) staff? The answer: build new state of the art facilities in accelerated time frames.

One such facility is located at British Rototherm, in Port Talbot, Wales. Cleanroom Solutions was tasked with the design and build of the brand new, 425 sqm cleanroom.

The facility was designed in a matter of days, built in four weeks, with production equipment installed at the end of week four. This proved to be an immense challenge and an even greater achievement, testament to the national effort we have seen throughout this pandemic.

The facility is an ISO Class 8 cleanroom to ISO 14644-1, which is required for production of high grade face coverings and masks for front line NHS workers. The cleanroom included changing room and goods in/out airlock for production materials. The facility was fully air-conditioned for comfort conditions.

Due to the extreme urgency of the build and difficulties getting construction materials at short notice the build programme had to be modified. The walls were erected before the steelwork and temporally supported until the steelwork was delivered and constructed.

The walls were then connected to the steelwork, and this was followed by the suspended ceiling. As soon as a section of ceiling was in place, a second team began working on fitting the fan filter units (FFUs) and lights. Finally, the vinyl floor was laid, enabling the client to start to move their production equipment in. Whilst the equipment was being installed the ceilings were sealed and the room tested and validated.

From planning to completion, the project was closely followed by national UK news outlets, such as The BBC and ITV news. Labour MP Stephen Kinnock visited the site as the project was nearing its end and was immensely impressed by the effort and workmanship involved with the facility, especially in keeping within such challenging time frames.

Upon completion, the Secretary of state for Wales The Rt Hon. Simon Hart visited the site to meet the team and highlighted how great it was to see British companies successfully working under extreme time pressures to manufacture high-quality PPE to protect our front line workers and the wider community against COVID-19.

Cleanroom Solutions Site Director, Sean Gaylard, said: "This has to be one of the most challenging cleanroom installations that I can recall us taking on and completing. In light of the current world pandemic with many manufacturers and suppliers still on furlough, we managed to have the cleanroom ready for the production equipment within four weeks. A great team effort."

British Rototherm Managing Director, Oliver Conger, added: "The commitment to meeting and achieving a very tight project schedule was tremendous and the quality of the build was first class. The team worked very well with our own operations team and this made it a real pleasure and we built up a very good working relationship with them and a high level of trust. We would highly recommend Cleanroom Solutions to anyone looking to build a cleanroom, particularly if you are under any time pressures such as ourselves."

Comfort and Appearance Important for Child Masks

In this pilot study, British researchers assessed the perceived wear ability of three facemasks (Vogmask, TuHao and ReSpimask) marketed in the UK as being designed to protect children against exposure to air pollution. Twenty-four primary school children wore each facemask during a standardized walking and running activity. After each activity, the children were asked to rate facemask wear ability in terms of parameters, such as perceived comfort, hotness, breathability and fit. At the end of the trial, the children compared and identified their preferred facemask. The main complaint about the facemasks was the children’s faces being too hot. The ReSpimask was most frequently reported as being perceived to be the hardest to breathe through. The TuHao facemask was the only adjustable strap mask assessed but was reported to be difficult to adjust. Facemasks with a nose clip were frequently rated highest for fit (TuHao and Vogmask). The patterned, cloth fabric Vogmask had significantly higher ratings for appearance and perceived fit. The results show children’s perceptions of facemasks are highly affected by the facemask’s design, hotness and perceived breathability. By making children’s facemasks more appealing, breathable, cooler and improving their fit, wear ability may be improved.

If masks are uncomfortable, annoying or embarrassing to wear, the motivation to wear them, or to keep them on, may be limited and they will provide inadequate protection. There is currently limited non-occupational research into the wear ability of facemasks, irrespective of whether they are certified (passing laboratory testing as being capable of filtering particulate matter, for example, capable of filtering 95% of small (0.3 µm) particles (i.e., the US N95 standard, equivalent to Filtering Face Piece 2 (FFP2) in Europe)) or not.

There was a significant difference in the level of comfort of the masks whilst walking (p = 0.013) and running (p = 0.003), with the children finding it more comfortable when walking. The Vogmask was given the highest mean score for comfort whilst walking (1.3) and running (0.8), and was ranked most comfortable of the three masks tested, by 67% of the children (χ² = 18.9, p < 0.001), ReSpimask was consistently the lowest rated and was ranked the least comfortable by 67% (χ² = 19.5, p < 0.001) of the children.

There was a highly significant difference between perceptions of the different facemasks’ appearance (p < 0.001). Vogmask had the highest facemask appearance mean rating (1.6) and ReSpimask had the lowest (−0.4). Vogmask had a higher rating than TuHao and ReSpimask (difference = 0.83, p = 0.005 and difference = 2.00, p < 0.001, respectively); TuHao had a higher rating than ReSpimask (difference = 1.17, p < 0.001).

After being asked to rate the facemasks’ appearance, the children were invited to explain their answer. Vogmask had the highest proportion of positive comments (85%), and the lowest proportion of negative comments about its appearance (11%). Fifteen children (63%), said they liked the design of Vogmask. ReSpimask had the lowest proportion of positive comments (15%), and the highest proportion of negative comments (77%) about its appearance; for example, many children said the ReSpimask looked like a nappy/diaper.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7312046/

Mask Cleaning and Disposal should be as Frequent as Stepping on a Foot Sanitizer

A nurse attending to an influenza patient one minute and entering the isolation room with a COVID patient the next should change not only her mask but all outer clothing exposed to the air.  She should also step on a foot sanitizer as discussed in our interviews with PathO3Gen

In actual practice people are changing masks frequently but not other garments.  There is a mask shortage and concern that there will not be enough CATE masks to meet demand.  So we need to take a fresh look at mask cleaning and disposal. Here is a comment from a South East Asia mask supply website.

To put things into perspective, a mask is not a special "germ magnet". It is not the only part that gets exposed to viral particles and germs - your hands, bags, shoes, outerwear, metro/mrt cards and mobile phone are probably more biologically contaminated. These are constantly in contact with foreign objects or your hands, whereas no one consciously brushing his masked faced against any foreign objects.

It is true that the mask is filtering the incoming air. Since most of the transmission is airborne, it stands to reason that the mask exterior will have more virus retention than other clothing.   However an alcohol wipe can be applied to the mask surface at any time. But in the low virus load environment which is typically where the non-isolation ward personnel are found the likelihood of virus accumulation and transmission from the mask outer surface is very low.

Mask rejection due to appearance is legitimate. Using our foot sanitizer analogy properly shined shoes are also important to many. But people below the poverty line welcome  shoes which are functional despite appearance. Used garments account for over 50% of the clothing sector by volume in many sub-Saharan African countries.

The conclusion is that mask appearance and surface contamination if properly prioritized are no longer dominant determinators of mask life..

Mask Choices for the Pandemic

The pandemic is spinning out of control. Everyone agrees that masks are the most effective weapon. But as shown in the last few Alerts CATE masks are seven times more effective than alternatives. The $64,000 question or maybe $64 billion question is how do we supply masks for at least half of the 8 billion people on earth.

Most CATE Masks are reusable. They can be worn many times. The captured particulate builds up in the filter media and over time will make the mask more uncomfortable. With many uses it will look less attractive. But as one of the British children participating in research comparing a CATE mask to a white disposable mask said, “ It doesn’t look like a nappy”.

If CATE masks are used many times and the supply is quickly expanded it should be possible within a matter of months to supply the world with sufficient masks. So the  overall value of old CATE masks needs to be compared to alternatives.

An earlier chart prepared by McIlvaine shows the perceived value of masks at various viral loads. For the next year we can assume that there will be high viral load.

At this high viral load here is a comparison of old CATE masks versus alternatives.

The perfect score would be 180. The old CATE mask is slightly less valuable than the new CATE mask but considerably more valuable than the alternatives.

The conclusion is that CATE masks are more valuable even at greatly extend use. Since sufficient quantities can be produced and worn, it is time to create a crash program to manufacture CATE masks.

Media Starting to Analyze Mask Fit and Its Importance

Here is a recent news article with coverage of recent studies comparing masks. It is heartening that the differences between masks are now being analyzed.

Cleveland.com reviewed 12 studies on the efficacy of masks, based on published research in recognized scientific journals. When choosing to buy or make a mask, recent research cites three factors as key: fabric, fit and ties.

The gold standard for medical professionals is still a properly-fitted N95. Experts told cleveland.com, however, that N95s are impractical for the entire population to wear. There are many consumer choices that can improve how well masks work. N95s are commonly used in hospitals, and need to be properly fitted, which is why the general public normally uses surgical or fabric masks.

Keep in mind that wearing even a simple mask can help stem the spread of disease, though a mask does not substitute for appropriate social distancing and hygiene measures.

Fit

Fit is a theme throughout the literature published on the efficacy of masks, though research experiments with fabric more than fit.

One study published in Nature on the efficacy of masks and face coverings notes the potential importance of fit in the context of the study’s results. Both surgical masks and unvented N95s reduced emission rates by 90% and 74%, respectively, without taking fit into account. Researchers noted that N95s, in this study, didn’t perform as well as a surgical mask.

“It may be that imperfect fitting of KN95 respirators allows for greater escape of particles from the mask-covered environment compared to the more flexible surgical masks,” the authors wrote. “Regardless, all surgical masks, KN95 and N95 respirators tested here provided substantial reduction of particle emission compared to no mask.”

So simply wearing the mask is helpful, though there are enough ways that people are wearing them incorrectly that there are internet memes poking fun at them. Covering the nose with a mask is crucial, so leaving it hanging on the chin or bunched up under the nose won’t work.

The way a normal cloth mask is structured can leave gaps between the cheek and the mask, which could allow for some issues with leaking virus. Essentially, the jet of air that comes out of the mouth when breathing or talking is going to look for a path where it isn’t blocked. If there’s a gap where material does not cover it, the air will redirect through those holes instead of being filtered through the mask.

A study published in “Physics of Fluids" tested how effective cloth and off-the-shelf masks are in obstructing air flow that contains respiratory droplets, which researchers recognize is a main transmission method of the coronavirus. In a demonstration for “Good Morning America," researchers showed the difference in their modeling in a common, blue, surgical mask. When the researchers did not press down on the wire nose clip for the mask, there was more leakage out of the top of the mask.

"The main thing to keep in mind is make sure it fits snugly on the face and any metallic wires or strips that are present, you should always try to press it down so it contours well to your face,” Dr. Sid Verma told GMA.

A study published in Extreme Mechanics Letters showed that surgical masks or cloth masks that aren’t fitted could allow for significant leaks. Trying to find a cloth mask with a wire that form fits it to your nose and face can help reduce any gaps. Researchers at the University of Illinois also suggested in the Extreme Mechanics Letters study that a more breathable fabric can help spread out airflow, reducing leaks through un-filtered areas. Adding another layer of fabric over the mask is also showing promise, though published research on that is limited.

Ties

The most common type of mask hinges on ear loops, rather than ties. Aside from some users complaining of discomfort around the ears, some studies show that ties that go behind the head can be more secure and work better for fit.

Researchers reviewed 29 types of respirators and face masks, and found that in all of the tests, the masks with ties outperformed the ones with ear loops. For example, in the tests for surgical masks, the filtration efficiency -- how well the mask blocks -- proved almost double that in the masks with ties as it did with the ones with ear loops.

Because the researchers tested effectiveness while subjects were moving around, they concluded that the ear loops might not provide enough tension to keep the mask snugly fitted.

Ear loops that are adjustable could help with fit. A review on best practices for cloth masks found that users should hold their mask to their nose and mouth while tying ties or ear loops. When tying a mask with behind-the-head ties, tie the top tie around the back of the head, and then at the base of the neck.

Fabric

There are many considerations when picking a fabric for a mask. Take a look at a regular, surgical mask. Behind the pleated front, the layers of fabric can pull apart. Multiple layers play different roles in stopping the coronavirus from spreading. One layer could absorb large droplets, stopping them from carrying out the coronavirus (but prompting you to need to dispose of or wash a mask). Then another would filter out smaller, aerosolized particles.

Having multiple layers made of different fabrics can also be helpful with moisture. Fabrics are grouped into hydrophilic and hydrophobic, meaning the fabric retains moisture or repels moisture. Having both of those types of fabrics in a mask design can be helpful in blocking droplets.

The number of layers is important in selecting a mask. Researchers from the University of Cambridge and Northwestern University tested a wide range of fabrics that could be used in homemade masks. The multiple-layer fabrics performed better than the single-layer fabrics across the board. Cotton and thick cotton performed well in filtering out fine particles. Other fabrics, like windbreaker material and denim showed a higher rate of filtration but aren’t as breathable.

"A mask which blocks particles really well but restricts your breathing isn’t an effective mask,” author Eugenia O’Kelly from Cambridge’s Department of Engineering said in an article on the university’s website.

“Denim, for example, was quite effective at blocking particles, but it’s difficult to breathe through, so it’s probably not a good idea to make a mask out of an old pair of jeans. N95 masks are much easier to breathe through than any fabric combinations with similar levels of filtration.”

A review of 25 articles referencing cloth masks, published by the Mayo Clinic, found fabrics with higher thread counts performed better than those with lower ones, and better still when layered. Researchers recommend a cotton with thread count of at least 100 threads-per-inch. Pleated masks are also recommended, which allow the user to pull the mask to the chin easily.

The “Physics of Fluids” study showed that wearing a bandana-style mask is significantly less effective than other masking methods. If you choose to wear a gaiter, make sure there are multiple layers to the gaiter, the Centers for Disease Control and Prevention recommends.

Silk also could be a promising fabric for masks, according to a study published in Plos One. One of the authors, a University of Cincinnati professor, studied the effectiveness of silk after thinking about water-resistance in silk caterpillar cocoons, he told Discover Magazine. Silk outperformed polypropylene, used in disposable surgical masks, and cotton, in repelling water. Silk is also breathable.

The most important aspect of masking is to wear one, and to wear it correctly, as well as following social distancing guidelines and avoiding crowds.

When picking a mask or making your own, consider first whether there are at least two layers. Then, assess the fit on your face and whether there are gaps that could be corrected with a nose wire along the top of the mask, or pleating. Those basics can help pick the right mask for you. When in doubt, a surgical mask with a wire to help fit fulfills many of these considerations, though the price could stack up and experts worry about the impact on the environment.

Also, be sure to wash reusable masks frequently, especially after being in areas with higher coronavirus risk.