Wishes For Another Happy, Healthy Thanksgiving

My how the years roll on — the fifth Thanksgiving with the possibility of covid-19 showing up as an unwelcome guest. This year should be fairly mild for covid, since we have just come down from the unusual August-September covid surge. (See the right-most low point on the curve below from J.P. Weiland.)

But the normal winter episodes of colds and flu will be gaining steam. Remember, all “these viruses travel through the air, so when people who are infected exhale, talk, or sing, then they expel the particles on which the virus is attached, and that goes out into the air.”  (Note 1.) 

Luckily, Thanksgiving-spread illness can be reduced or completely avoided with these three simple measures, as have been advocated for years.

- Stay home if you’re sick. “We know it's hard to miss those family functions, but if you're sick with the flu, fever, or a cough that won't go away, stay home. … Someone can bring you a plate of leftovers rather than spreading those germs.” (Note 2.)

- Have plenty of fresh air — every reader of this blog will know all about this by now! Real fresh air per your heating system, or partially opened windows, and also clean air from portable air purifiers. As we said in 2022, “good fresh air ventilation is always a good thing — with a house full of more people than usual, having a few windows cracked open provides fresh air and prevents overheating if you’re in a cool climate.”

- And, for complete safety, everyone can do an in-home covid-19 antigen test before traveling to the family gathering. As we said in 2022, “For the antigen testing, all that is needed is for all participants (including children age 2 and older) to do the testing on the same day, prior to gathering together.”

Wishing you all a healthy and happy Thanksgiving!

Note 1 - Per Susan Arnold, PhD, associate professor of environmental health sciences at the University of Minnesota School of Public Health, as quoted in:

https://www.jacksonville.com/story/news/2024/11/21/thanksgiving-staying-healthy-cold-covid-19-flu-holiday/76477174007/

Note 2 - Per Kevin Hall, communication chief for the Lexington-Fayette County Health Department, as quoted in:

https://www.lex18.com/news/covering-kentucky/spread-cheer-not-germs-a-holiday-recipe-for-illness

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How to Buy an Air Quality Meter (Hint - It's Tricky)

We recently got this question from “Jack”. Here is our reply.

Jack, you’re wise to ask this question. It’s surprisingly tricky. There are three main components in air affecting “air quality”: carbon dioxide (CO2), other gaseous air pollution including organic chemicals and ozone, and small particle air pollution as from wild fires.

Carbon dioxide (CO2) is the most important factor for covid-19 and other airborne contagious diseases. (We will report on other types of meters in the future.) The CO2 impact is two-fold: CO2 itself begins to be deleterious to humans at only double its concentration in fresh air. At the levels that have been the norm for well-designed and operated buildings (900-1000 ppm), recent studies have shown a small but measurable amount of reduced cognitive performance compared to that with 100% fresh air (now around 425 ppm minimum).

The more important factor with covid-19 and other airborne viruses is that CO2 levels provide a means of measuring the amount of fresh air PER PERSON in the room. This ability is because people are continuously breathing out high levels of CO2 (around 40,000 ppm!). These high levels mix in with the room air and the incoming fresh air and come into equilibrium. There is a mathematical formula for translating the resulting CO2 level into fresh air cfm (cubic feet per minute) per person. And since air into the room or building must equal air out, the more air coming in leads to more airborne virus being flushed out.

As the covid-19 pandemic developed, we in the ventilation industry generally doubled the amount of fresh air/exhaust air in buildings, from 15 to 30 cfm per person. (We thus returned to the healthy fresh air levels being provided in the U.S. just after Spanish Flu pandemic in 1918!) Allowing for some variation in meter accuracy, this ventilation level corresponds to a CO2 reading of 800 ppm.

The technical problem is that 99% of the meters sold today are worthless. (See above picture for examples that failed our tests.) Either they start out wildly inaccurate, or they become miscalibrated within a few weeks. Decades ago, when the natural CO2 level was around 400 ppm, and buildings let a lot of air leak in and out, the industry started “automatic” CO2 meter calibration by assuming that buildings would regularly be exposed to indoor CO2 levels approaching the level of outside air, or 400 ppm. They devised meters that would keep track of the lowest CO2 reading over the course of a few weeks, and then readjust the calibration assuming that this lowest reading was 400 ppm! This is an obviously very wrong thing to do these days, with outdoor air CO2 at 425 ppm and rising, and more importantly, with better-built buildings that NEVER have the indoor air CO2 get anywhere close to such a low reading. (I know, I have measured this in multiple instances.)

Nevertheless, most meters sold today still do the auto-calibration, often cleverly called Automatic Background Calibration (ABC). Some meters allow you to turn off the ABC, but, amazingly to me, many meters do not allow you to turn it off.

Therefore, to get a functional CO2 meter, you need one that is accurate to start with, and does NOT have ABC. And to get a user-friendly meter, you need one that gives you a convenient color-coded GREEN signal when the measured ppm is less than 800. I have tested dozens of meters since 2020, and we now have only two that we recommend. We sell verified and upgraded versions of these meters, or you can buy them directly and take responsibility for proper set-up and labeling.

The Big Meter. This is a meter, typically for wall-mounting, that gives your customers, visitors, and building occupants a clear signal that you have healthy fresh air. Here is a meter at the entrance to a high school.

See the Apr. 29th, 2022 blog post for more details and how to order. Both meters can be ordered by emailing safetulator@kohlerandlewis.com or call Suzanne at 603-352-4828.

The Small Meter with a Graphic History: This is a small desktop meter, explained in full detail in this blog post of Dec. 15th, 2023. In addition to the current ppm reading and color code, it shows a colored bar graph with 24 hours of history. Both meters can be ordered by emailing safetulator@kohlerandlewis.com or call Suzanne at 603-352-4828.

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Isolation Without Infection

The State of the Virus

The summer/fall covid-19 surge is finally receding — while it raged, the amount of virus circulating rivaled the typical winter peaks except for the deadly Omicron wave of the winter of 2021-2022. See the graph below from J.P. Weiland.

A Personal Case Study

The disease entered my own family recently, starting with one of the granddaughters, and showed up positive on an antigen test the morning that some of us were literally on the way to the airport for a trip. (It’s always good to test before an airplane trip — much better to find out while you are still at home instead of at a far-away or foreign location!) Although my wife tested negative that morning, the trip was canceled, and we started isolation measures at home — both of us masking and with windows open, with the weather being mild.

She was starting to feel some scratchiness in her throat, and in the evening, she tested positive with a faint red line on the test.

Our blog post of Feb. 9, 2023 gave detailed instructions for the best method —setting up the sick person in a single bedroom, or a single bedroom and bathroom. We did this for the acute phase of the infection, where my wife was in bed most of the time, and with a fever. This lasted about 36 hours.

As she started to gradually recover, we wanted to have her be able to spend time in other rooms of the house — her home office, and shared time in the kitchen. To accomplish this, we switched directions on our large amount of fresh air ventilation. We set up two dual window fans in a seldom-used room of the house to draw in fresh air 24/7, and then cracked open the windows a few inches in the other rooms of the house, effectively giving every room an exhaust fan, removing virus-laden air from the house right away in every room.

I monitored the effectiveness of this scheme with CO2 meters, which typically kept the CO2 less than 500 ppm — achieving a very high level of airflow.

We knew her contagious stage (positive antigen test) was going to last a week or more, and it did — the first negative test eventually came on Day 11.

In the meantime, she had her bedroom, bathroom and office, where she didn’t need to wear a mask. When we were both in the same room, we both were masked. We had our meals “together” in separate rooms, and connected via computer or phone. As she continued to recover, we even did the dishes together, both in our excellent masks.

A Note on Masks

I mostly wore the BROAD Airflow mask that we have discussed many times — see the blog post of Sept. 12, 2024 for example. This is such an excellent mask for someone who wants to avoid infection, in that it provides HEPA-filtered air at a positive pressure so any leakage is outward, the safe direction. (I used the enhanced version that we make, where a slight internal air leakage is fixed, improving the efficiency.)

But this mask is NOT what to use for an infected person. Here the mission is to carefully filter the exhaled air, with no leakage. Incoming air does not have to be filtered at all. That is, the mask need for an infected person is the opposite as for someone exposed to industrial dust or wildfire smoke in the air. Both mask types have a one-way airflow valve, but the airflow direction is opposite. Masks with one-way air valves can be purchased with the valve in the exhale direction, but not in the inhale direction.

So I made some new masks by removing and reversing the airflow valve, or adding a valve to a regular N95 mask. This change makes the mask much more pleasant to wear, with lots of cool incoming fresh air that does not have to get restricted by filter material. The breathing-out air is still filtered effectively by the well-fitting N95 mask.

A Final Note

It is an odd experience — taking careful measures the best you know how to do, and finding out after a three-day delay if what you were doing was successful! (Three days is the typical incubation period for the current variants, from exposure until the virus builds up enough to show symptoms or a positive antigen test.)

But research continues to accumulate showing that each additional infection of covid-19 comes at substantial extra risk, particularly for older people, and our recent experience shows that you need not roll the dice — you can take excellent care of the sick person or people while avoiding spreading the disease to others. See links below:

What Repeat COVID Infections Do To Your Body, According to Science, SELF

COVID-19 Reinfection Ups Risk of Long COVID, New Data Show, University of Minnesota

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A Mask for all Seasons

Summer/September Surge Continues

The amount of virus in circulation continues to be high, and is leveling off in most of the country, ready for a decline. However, here in New Hampshire, a couple of college towns have had huge peaks, which I attribute to the return of the students.

A Multitude of Masks

In addition to good fresh air ventilation and selective at-home testing, masks are among the best tools we have available for reducing your risk of getting covid-19, and for reducing the spread of the disease. Here is our annual roundup of masks for many different purposes. It’s mostly a repeat of the Oct. 19, 2023 post with one new addition at the end.

Easy-to-breathe, 100% effective fan/HEPA filter mask. We have been using these since April 2021, the "BROAD AirPro Mask Rechargeable Reusable Air Purifying Respirator with a HEPA Filter”, from Amazon ($46) and other sellers. The HEPA filter is 99.97% effective for virus-sized particles, and the fan slightly pressurizes the mask, giving you a much higher percentage of cool, fresh air compared to regular N95 or N100 masks. Really a breath of fresh air! Replacement HEPA filters, rechargeable batteries, etc. are readily available.

Another nice feature about this system is that you can pair the fan/filter mechanism with any N95 mask of your choice. (You can use any mask really, but the N95 works best for us — our current favorite is the Kimberly-Clark PROFESSIONAL N95 Pouch Respirator (53358), NIOSH-Approved, Made in U.S.A., from Amazon or others.)

In the blog posts, we have talked about these Airpro masks several times over the years. Our Jan. 4, 2022 blog post includes helpful information with four videos sharing information on the Airpro mask, how to sterilize masks, as well as how to modify an N95 mask to fit the Airpro hose.

Masks with Exhalation Valves. If you are not contagious, you can use this type of mask without endangering those around you. These masks are a simpler version of the Airpro mask in that they give you a higher percentage of cool, fresh air — better quality air to breathe and less of your own exhaled air. They are also your best protection if you have to be out in the smoke-filled air from wildfires or locally-generated dust.

The best models are “N100” masks, tested to be 100% effective. I tried out one of these (3M Personal Protective Equipment Particulate Respirator 8233, Amazon, $10/mask) and found it to be serious, well-made, and readily adjustable for a good fit. Breathing was no more annoying than with N95 masks.

“N95” masks with valves: many models of these are available — it’s best to find one by trial-and-error that fits you well.

A good fit around all the edges is essential for any mask. (Not so much for the Airpro, where a little air leaking out is normal.) If you exhale, and feel air leaking out, perhaps blowing toward your eyes, then there also will be unfiltered air leaking in when you breathe in. Try bending the nose area of the mask. If you can’t get a good fit, you may need to select another brand.

Hot air mask sterilization and reuse. There was a study done in August 2020 at the University of Illinois which documented how to sterilize your disposable masks, rather than throwing them away after each use (https://hmntl.illinois.edu/news/17342). We have a video demonstrating this — all it takes is a standard crockpot set on “Low”! See Sterilizing Masks video.

Note that sterilizing the Airpro mask is not so important since the incoming virus is trapped in the HEPA filter, not in the mask. Do not put the fan-filter unit in your crockpot — this would reduce the lifetime of the lithium battery.

An almost-invisible mask. We have tried a few other “nose masks” over the years without success but here is one that appears to actually work, and we have found it is tolerable to wear. Search for "Nose Mask Nose Air Clean” — currently $18 for a package of three, on Amazon. They are rated at 70% effective for PM2.5 particles, which is the size that includes wildfire smoke and the covid-19 virus. This effectiveness is probably better than the real-world effectiveness of regular N95/KN95 masks, which are hard to get to fit perfectly. Get the “general type”, and pick one of several sizes available. After use, you can sterilize it in a crockpot as described above. It's small enough to carry in a keyring pill capsule, so you can always have it with you when the need arises. Replacement filter elements are available. And as you can see from the promotional picture below, using this mask also makes you happy!

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The Summer Surge: One Million New Infections Daily

One Million New Infections Daily

Wastewater sampling at several dozen sewer plants across the nation takes samples and counts the amount of covid-19 virus in a given volume of sewage water. This has been going on since 2020, so it gives a great perspective on the current situation relative to past times.

Scientist and infectious disease modeler J. P. Weiland has been taking this information and using it to calculate the number of people who currently have the covid-19 disease. The results are only approximate, as the sampling sites are limited in number, and Weiland depends on some assumptions, including that the average infection lasts ten days.

Here is his latest summary from https://www.threads.net/@jpweilandmodels?hl=en

and here is the graph going all the way back to 2020:

Here are the four regional breakdowns, and the CDC's label for the national level from https://www.threads.net/@jpweilandmodels?hl=en:

Thriving During the Summer Surge

As the case rates rise, there are more celebrity infections in the news, and you may know of people personally who have come down with covid-19. I have a friend who joined a group of 40 people for a week's vacation in Europe. One person picked up the disease on the airplane trip, and it spread to a fourth of the group. Luckily, no one had to be hospitalized, but they found that it took as long as two weeks to recover completely so that an antigen test returned a negative result. (A negative antigen test means you do not have enough virus to be contagious to others — it's equally effective on the front end, for everyone gathering together, and for the back end, when you know you can stop isolating.)

Nevertheless, we have effective risk reduction measures that can allow:

• Workplaces to avoid covid transmission,

• Schools to re-open without having covid outbreaks, and

• Friends to gather together and leave the virus behind.

Best results depend on testing before you gather. If you test on the first day, and again on the third and fifth days, that will catch almost all infections. Even a single test on the first day will catch a large percentage of the infections, and testing people who get sick can allow safe isolation. Remember that more-or-less half of all infections do not have enough symptoms for the person to notice. [See May 31st, 2024 blog post.]

The second most effective strategy is fresh air ventilation — a popular topic in this blog! [See May 9th, 2024 blog post.] Remember that good fresh air greatly reduces transmission of all airborne diseases — an 80% reduction in one study [see Dec. 16th, 2022 blog post]. Just open the windows or see our August 31st, 2023 blog post for more detailed advice. And note that this is a great time for outside dining!

All the other measures can have an impact, but these are the big two.

Enjoy a healthy remainder of your summer!

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The Virus Is Getting Smarter — Not So Much For The Humans

The Virus

The Covid-19 Virus continues to evolve with new variants that do a better job passing the infection on to other people. The amount of virus in our communities, as measured by the fragments detected in municipal sewage, has put most of the country in the “red zone”.

https://www.newsweek.com/covid-19-map-wastewater-levels-1932576 

Levels have been rising steadily since May. Nationally, one in 43 people are currently infected (and infectious). 

https://www.threads.net/@jpweilandmodels?hl=en

It looks to me like the virus is headed to set a record for a summer peak, and arrive at a level similar to all the past WINTER peaks except Omicron. This outcome is probably the result of two factors that are typical — a new variant more transmissible than the last, and the usual lack of good fresh air ventilation when the A/C is on; and two factors that are new — waning immunity from vaccinations and previous infections, and a new pandemic low point for the number of people who are taking protective measures such as masking, testing, and avoidance of dense crowds.

The significant good news is that while the sewage levels are rising, so far this is not the case with hospital admissions and death rates. 

"Evidence suggests ... that COVID-19 is continuing to lead to less severe illness in the population. COVID-19 can still lead to severe outcomes, however, particularly for individuals in specific risk groups, such as immunocompromised individuals, people age 65 and older, individuals with heart disease, lung disease, or diabetes."

https://vermontbiz.com/news/2024/july/30/vdh-covid-cases-continue-rise-no-deaths 

The Humans

The dominant human approach seems to be trying to get the virus to behave as desired by simply ignoring it, plus watering down any suggested safety measures — the CDC now says people who test positive for Covid don’t need to isolate for five days.

https://www.nbcnews.com/health/health-news/covid-isolation-guidelines-cdc-updated-positive-cases-rcna163292

And, with apologies to Casablanca, we are expressing shock! shock! to find that infections are still happening.

As on cruise ships, with thousands of people aboard, and no pre-boarding testing or covid safety measures in place. "Cruisers have been especially shocked to come down with COVID-19 on their recent trips. Many are sharing stories on social media about entire families getting sick during or right after they left the ship.”

https://www.aol.com/news/cruisers-contracting-covid-19-during-005855433.html

And as at the White House, which in March dropped testing for those meeting with President Biden.

https://www.motherjones.com/coronavirus-updates/2024/07/biden-covid-test-cdc-pandemic-safety/ 

And even after (of course) the president tested positive a few months later, he didn’t always wear a mask when he continued to meet with people (and this was in accordance with CDC guidelines)!

https://abcnews.go.com/US/wireStory/biden-covid-19-wear-mask-cdcs-guidelines-112073485

And as at the Olympics, with zero covid safety measures in place, and covid infections sweeping through several teams. 

https://www.aol.com/course-covid-why-no-official-203600727.html

This is not to say that everyone should be avoiding getting Covid-19. But if you are to fully enjoy your cruise, or exercise your duties as president, or perform your best as an athlete, or simply continue a healthy life as an assisted living resident, you need to avoid Covid-19.

As we said in our blog on August 18, 2022, may we please have an INTELLIGENT New Normal?

Can We Please Have an Intelligent New Normal?

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