IHME projections on lives saved by mask

Anchorage Mayor Ethan Berkowitz has expressed his vote of no confidence in the citizens of the state’s largest city and ordered them all to start wearing masks in public places to prevent the spread of the SARS-CoV-2 virus.

If Alaska Mike Dunleavy joins in, the latest modeling from the Institute of Health Metrics and Evaluation (IHME) at the University of Washington projects that universal masking could save the lives of 11.81 Alaskans between now an Oct. 1.

Dunleavy, a Republican, appears unlikely to jump on the bandwagon. Berkowitz, a Democrat, appears to be relishing the idea that he can save some subset of 11.81 people by adding fuel to the partisan fire of masking.

The mayor could have simply made a plea to Anchorage residents to mask up to make their neighbors feel better, but there is nowhere near the political advantage to doing that. So Berkowitz played to the maskers.

And there are a lot of people in this state who seem to believe that their lives are being threatened by others not wearing masks. They are right to feel that way, too.

You don’t infect yourself with an infectious respiratory disease. You get it from someone else. So it’s fair to blame your neighbors.

How much you should blame them is the big question.

Weighing the odds

On average from 2014 to 2018, according to the vital records from the Alaska Division of Health, infectious respiratory diseases – pneumonia and influenza – killed 69 people per year in Alaska. That breaks down to about 5.75 per month or 17.25 in the three months between now and Oct. 1.

So – if the IHME numbers are to be believed – your potentially COVID-19 infected neighbors are trying to kill you at about 68 percent of the rate that your normally influenza/pneumonia-infected neighbors are trying to kill you.

Take that for what it is worth. I am neither for masks nor against masks.

When I go into public places, I wear one. Not because I think it is doing any good, but because it would appear to make fewer people uncomfortable than not wearing one.

There is a lot of masksteria out there, and some people are clearly convinced that universal masking is the solution to the pandemic problem of the new millennium. They will quickly tell you how much better the situation in those countries where people regularly mask up.

Better elsewhere?

The last country I heard cited was Thailand. Thailand is doing great in the battle against COVID-19. It is not doing so great in the battle against infectious respiratory diseases in general.

The World Health Rankings report an annual death rate for pneumonia/influenza of 47.82 per 100,000 people in Thailand. The U.S. rate is 10.75 per 100,000.

South Korea is another country regularly cited as doing well against COVID-19 because it regularly masks up. Its pneumonia/influenza mortality rate is 21 per 100,000, about twice that of the U.S.

Taiwan – another country where masks are common, everyday attire – reports a pneumonia death rate (which appears to include influenza) of 56.9 per 100,000 for 2018. That is about five times the U.S. rate.

Is there any reason to believe this is linked to people regularly wearing maks? Actually, there is.

In one of the rare, randomized clinical trial studies of masks, Australian, Vietnamese and Chinese scientists examined masking in 14 hospitals in Hanoi in 2015. They found that health-care workers who wore their masks for more than 70 percent of the work day were significantly more likely to contract an infectious respiratory disease than a control group who wore masks for half that time or less.

There was no unmasked control group in the study because it was decided that asking people working in a pathogen-riddled environment to go without masks would be unethical.

Random clinical trials are considered the gold standard of medical research. Not long after the pandemic blew up in March, the authors of the peer-reviewed study in BMJ, formerly the British Medical Journal, published a “response” to their earlier study.

“As authors of the only published randomized controlled clinical trial of cloth masks, we have been getting daily emails about this from health workers concerned about using cloth masks,” they wrote. “The study found that cloth mask wearers had higher rates of infection than even the standard practice control group of health workers, and the filtration provided by cloth masks was poor compared to surgical masks. At the time of the study, there had been very little work done in this space, and so little thought into how to improve the protective value of the cloth masks. Until now, most guidelines on PPE (personal protective equipment) did not even mention cloth masks, despite many health workers in Asia using them.

“Health workers are asking us if they should wear no mask at all if cloth masks are the only option. Our research does not condone health workers working unprotected. We recommend that health workers should not work during the COVID-19 pandemic without respiratory protection as a matter of work health and safety.”

They did not take a position on public masking, or offer any suggestions on exactly how much time people should spend behind the mask. Their study was not, however, the first to link face coverings and respiratory diseases.

Behind the veil

Researchers studying veils in Saudi Arabia in 2001 noted a similar connection.

“It is customary in clinical practice and elsewhere to put on a mask for protection against infection, dust, and so forth,” they reported. “The veil, which is traditionally worn by women in many Muslim countries, especially in Saudi Arabia, may have a similar effect.”

What they found was the opposite.

“Veil wearing was practiced by 58 percent of the sample,” they said. “Respiratory infections and asthma were significantly more common in veils users.”

This would make a certain amount of sense in terms of evolutionary biology. Mammalian lungs developed not only to take in oxygen but also to get rid of pathogens. This is why there is so much discussion of the “viral shedding” by people infected with SARS-CoV-2, especially those who are asymptomatic.

World Health Organization (WHO) Dr. Maria Van Kerkhove put the torch to a media firestorm at the start of the month when she suggested the asymptomatic carriers – those who have the disease but don’t get “sick” – weren’t shedding many viruses. 

She subsequently rolled that back by observing that “the majority of transmission that we know about is that people who have symptoms transmit the virus to other people through infectious droplets. But there are a subset of people who don’t develop symptoms, and to truly understand how many people don’t have symptoms, we don’t actually have that answer yet.”

The fear of asymptomatic carriers – “you could have it and be infecting others without even knowing” – has been one of the main forces driving those who want the government to order mandatory masking as Berkowitz did in Anchorage.

And, as with almost everything in America today, this has split the citizenry between those who believe in government action if it “saves even one life” and those who think the government should have more substantial justification before exerting its authority to trump individual judgment.

Wanting to save lives in noble. Wanting to preserve individual liberties – the very foundation of any democracy – is equally noble.

Sadly it appears hard for either side facing off across the country’s vast political divide to devise an agreeable path between these two nobles causes that leads toward the greater good. The maskers here are generally, though not all (see this commentary by Don Mitchell), on the left. The anti-maskers are generally, though not all, on the right.

Pandering?

Whether Berkowitz’s action was good public policy or pandering to a leftish political base depends on how much you believe the models and how you view the numbers. Given that Anchorage represents about 40 percent of the Alaska population, you could figure that mandatory masking in the city could save 40 percent of those 11.81 deaths or 4.724 lives.

Certainly five lives matter to the friends and relatives of the dead. You have to be pretty cold-hearted to suggest that some people should be allowed to die.

On the other hand, it’s a biological reality that we’re all going to die, and we do. In an average month in an average year, state Division of Health figures indicate we lose 33 Alaskans (median age 47) to accidents and another 15.3 (median age 34) to suicide.

The three-month projections there – 99 people dead in accidents, 46 dead of suicide – dwarf the projected deaths for COVID-19 for the same three months. It is the same for pneumonia/influenza, which kills the same number as suicide but with one big difference.

The median age of those dead is 80. In that regard, the pneumonia/influenza deaths are similar to COVID-19, which is killing mainly the old. 

Still, if the modeling is correct and if Anchorage residents comply rather than revolt, Berkowitz’s order could save some lives. How much you can trust the modeling is a whole other issue. When a much talked about model put together by the Imperial College-London was applied to Sweden, it projected 96,000 deaths there by July.

In fairness to the modelers, that was but the point of 95 percent probability within a range of 52,000 to 183,000 deaths. As of this writing, the death toll in Sweden stands at 5,280 or about a tenth of the lower end of the range.

The models are not all that accurate. IHME’s model could be off by a 10 times on the low end, and the difference made by masks in Alaska by Oct. 1 could be 118.1 lives saved instead of 11.81.

There is no way of knowing. There are no blacks and whites here. There are a lot of shades of gray. At least as the discussions applies to COVID-19.

Saving lives

If the focus is simply on saving lives, there are a lot of other things we could do that are known to work.

Sixty-nine people died in motor vehicle accidents in Alaska in 2018, the last year for which data is available. That’s an average of 5.75 lives per month or 17.25 by Oct. 1.

Traffic studies have shown that reducing speed limits to 30 mph or less cuts death rates in motor vehicle accidents by about 90 percent. If Dunleavy were to order a statewide reduction in speed to 30 mph, the data indicates we could save 15.5 lives between now and Oct. 1 – 3.5 lives more than the COVID-19 model predicts for mandatory masking.

But then if a governor already threatened by a recall were to do this, he would almost assuredly be recalled. So that’s unlikely to happen.

On the other hand, Berkowitz could order Anchorage businesses and offices to pump a lot more fresh air into their buildings. Fresh air has been known to be protective against infectious disease since the Spanish flu a century ago.

Nearly all of the COVID-19 blow-ups that have been tracked back to their origins were found to have happened in enclosed spaces.

“Several outbreak investigation reports have shown that COVID-19 transmission can be particularly effective in crowded, confined indoor spaces such as workplaces (offices, factories) and during indoor events – e.g. churches, restaurants, gatherings at ski resorts, parties, shopping centers, worker dormitories, dance classes, cruise ships and vehicles,” the European Centre for Disease Control and Prevention (ECDCP) reported this week.

“In a study of 318 outbreaks in China (where SARS-CoV-2 is believed to have originated),  transmission in all cases except one occurred in indoor spaces.”

The report suggested merit to additional ventilation and filtering.

“High Efficiency Particulate Air (HEPA) filters have demonstrated good performance with particles of the SARS-Cov-2 virus size (approximately 70−120 nm) and are used in aeroplanes and in healthcare settings,” the report said. “(But) the role of HEPA filters in buildings outside of healthcare settings in preventing transmission of infectious diseases is unclear.”

The report was less circumspect when it came to ventilation.

“The minimum number of air exchanges per hour, in accordance with the applicable building regulations, should be ensured at all times,” the authors wrote. “Increasing the number of air exchanges per hour will reduce the risk of transmission in closed spaces. This may be achieved by natural or mechanical ventilation, depending on the setting.”

Berkowitz could have ordered Anchorage businesses to install HEPA filters in their heating, ventilation and air-conditioning (HVAC) systems and to keep their doors open to allow an influx of fresh air, but that would have been unlikely to produce the political return inherent in the mandatory masking that has for some become the political symbol of a safer tomorrow.

If only.

How well masks work remains a question with an unknown answer. Scientists are now demanding that a peer-reviewed study that was published in the Proceedings of the National Academy of Sciences claiming masking could save tens of thousands of lives be retracted as scientifically unsupported.

Scientists do “agree that masks probably do offer a level of protection,” wrote Stephanie Soucheray at the University of Minnesota’s Center for Infectious Disease Research and Policy,  “but right now there is no way to tease out how much protection masks offer versus physical distancing of six feet or more, or hand washing.”

“The world is much messier than we would like to admit,” David Kreibel, a professor of epidemiology at the University of Massachusetts-Lowell, told her. “We do our best and admit our uncertainty.”

About the only thing that is wholly clear is that if you stay away from other people, you will not catch the disease.

(For those interested in more on this subject, the government of New Zealand has pulled together an excellent “Review of science and policy around face masks and COVID-19.” It can be found here.)