This op-ed by Salmaan Keshavjee and Tom Nicholson in the Wall Street Journal raised some questions for me. In the op-ed they recommend two “low-cost and effective approaches” for mitigating the risks of spreading COVID-19:
The installation of a simple technology that deactivates germs could make public spaces safer against viruses and bacteria for decades. Also, while new vaccines are making the headlines, a nearly century-old vaccine that costs pennies per dose and is already used by hundreds of millions of people world-wide can help reduce severe outcomes from respiratory infections.
The former tool is upper-room UVC germicidal lighting. These fixtures look like glorified bug-zappers, but the bugs they zap are viruses and bacteria, not insects. The technology has been around since 1937, when it was first used against a measles outbreak—an airborne virus more contagious than Covid-19—in a Philadelphia school. Studies show that when optimally used in concert with good ventilation systems, UVC germicidal lighting provides the same effect as completely replacing the air in a room more than 10 times an hour. This reduces transmission and is a safe, effective layer of protection against threatening airborne diseases in crowded indoor settings.
The devices are manufactured in America and have been supplied to U.S.-funded programs around the world through the Centers for Disease Control and Prevention and the U.S. Agency for International Development. Outfitting indoor public spaces with these devices would cost considerably less than the trillions already spent by the federal government to mitigate the economic impact of this crisis. Our data from implementation of this approach in Oklahoma City indicate that installing these bug zappers in a typical building costs less than $6 a square foot. Maintenance and upkeep are cheap and simple. From Utica College in New York to the Salvation Army of Central Oklahoma, and from Los Angeles International Airport to the Cambridge Friends School in Massachusetts, these lights are already on and providing a layer of important protection.
The second tool is a vaccine that hundreds of millions of people have taken for years with almost no side effects—the antituberculosis vaccine BCG. It has been used for almost a century to protect the most vulnerable against tuberculosis and can be almost immediately produced in large quantities at low cost. A study funded by the National Institutes of Health and published last month in the journal Cell showed that BCG vaccination triggers a general immune response that decreases viral respiratory tract infections by 79% among the elderly.
My question with respect to the first strategy is how widespread is the use of these lights in hospital settings presently? I they’re not universal why not?
With respect to the second strategy, is there a reason it should not be implemented of which I’m just not aware? I don’t know enough to react.
BCG first. The evidence just isn’t that good. In the study linked below, better than most studies cited but still not what we need, it takes advantage of a sort of “natural experiment” where countries that were giving BCG stopped. No reason to think that BCG given in may is better than in June. They found no protective effect that could be explained by BCG. There is also the question of whether BCG given now has the same effects as given when a child, assuming it really does work. I think it is also difficult to scale up production. So how much time and money do you want to spend on stuff when you have no idea if it works. (Note that these 2 guys are TB researchers.)
UV light? Practical experience has shown that in most situations UV light does not make a difference, plus $6 a square foot is still a lot of many, plus you have maintenance. A lot of ORs have them. Hard to find any difference in infection rates. Part of that may be air turnover rates. In most procedural areas that is pretty high, turning over every 3 minutes or so. Probably best used only in the highest risk areas, understanding that they may not do that much.
Lets say you are in the hospital waiting room next to some with Covid, loudly crying because Mom is dying of Covid. You sit next to them for 20 minutes. Technically you are a high risk exposure. Now suppose you have UV light in the room. Even the most optimistic numbers I have seen for lights compatible with people suggest you kill the virus in 8 minutes. Probably if you are right under the light. So lets assume 10-12 minutes to kill virus. That crying person is continually generating virus in the room. You still have a large exposure. Plus if you have droplet exposure not really clear how much penetration you get to the virus suspended in spit, or whatever.
So it sort of makes sense, though we almost never see a change in infection rates when we install them (they are pretty though, especially at night), in an area like an OR or procedure room where you leave the light on all night and it “sterilizes” the room. Not sure it does much in a dynamic situation. So again, how much do you want to spend for unproven tech?
Steve
Thank you, steve. Basically, you’ve confirmed my uninformed kneejerk reaction.
Forgot to link the BCG study, or rather a synopsis of it.
https://www.sciencedaily.com/releases/2020/09/200921115550.htm
Steve