Avoiding & Preventing COVID (& other airborne illness)
With public health measures relaxed and a new, immune evasive wave on the way, there are things experts and studies say will reduce your risk of catching COVID or getting seriously ill if you do catch it.
Although many long term impacts still unknown, what we do know gives us good reasons to avoid COVID and avoid children getting it.
This is part of a series of posts on COVID. As the media and governments are now sharing very little information on new covid variants, or ways to avoid getting infected (or even encouraging people to catch COVID so they don’t catch COVID), I feel obliged to share the things I’ve learned as this information is not widely so that others can make informed decisions.
I’m not a health expert, and none of this is health advice. You should apply a healthy dose of scepticism to this, and check the sources I’ve linked against Media Bias Fact Check.
Updated 19 May 2024: Added information on air purifiers, Corsi Rosenthall Boxes and BLISK12 probiotics.
Diet, Sleep & Exercise
As with most things, maintaining good general health puts you in a better position to fend off an infection. Getting good sleep, maintaining a good diet and exercise all contribute to your health.
In one study of almost 600,000 people, eating well is associated with lower risk of contracting COVID by 9% and severe COVID 41%.
Sleep and rest are important when sick with COVID, trying to push through even a “mild” infection increases the risk of severe or long lasting illness.
Once you’re recovering from COVID, easing back into physical exertion. may help your long term recovery. Exercising too hard, too soon can lower the baseline for PEM — post exertion malaise (a fancy term for “you will get tired easily and frequently”).
Health Navigator (NZ) has a schedule for gradually getting back into exercise after COVID, and the CDC has a pacing guide for adults and children suffering from Long COVID.
Clean Air
Initial Infectious Dose
Before COVID I thought you just got sick, or didn’t get sick, but I’ve since learned there’s something called “Initial Infectious Dose” — how much virus did your body ingest when you got infected?
A lower initial dose can mean you get less sick (or if low enough, maybe even avoid getting sick), and, conversely, a higher initial dose may increase the risk of severe illness.
So if, for example, you discover a family member is sick, and you think you’ve been exposed, there is still benefit to taking more precautions like donning masks, ventilating the space, or going outside.
Masks
Countries that adopted masks early had significantly fewer deaths than those that did not.
N95 (aka P2) masks offer 2 to 3x better protection than surgical or cloth (according to MicroCovid.org)
The 3M Aura N95s fit a lot of different face shapes (but not all). I’ve found boxes of these in my local hardware store. I’ve also heard that duckbill shaped masks can be good for small faces.
Here’s a video on how to do a fit test for an N95 mask (which will improve it’s effectiveness).
N95s degrade quickly after first use (not visibly, but the protection is less good), you can prolong their life by putting them in a paper bag for 7 days before next use, but best to use a fresh one if you’re going somewhere risky.
Now that most people are not wearing masks you can expect there’ll be a lot more COVID in the air. You may want to consider an elastomeric mask which provides a better seal and decrease the chances that COVID will slip into the air you breathe.
Ventilation
The pandemic has been a missed opportunity to make improvements on the quality of air we breathe. Just as cholera led to the understanding of the importance of clean water, COVID is leading to understanding the importance of clean air. For example, a venue in Japan that provides public readings of the CO2 levels to demonstrate good air quality so patrons feel safe in the COVID age. High levels of CO2 indicate a space is poorly ventilated and so the risk of covid is higher. This WP article on it goes into some detail.
There’s RavenApp that provides info of air quality and other safe covid practices for local businesses (it’s only just getting off the ground sadly so not heaps of info in there yet)
If you want to go all in on risk prevention, you can even get a portable CO2 monitor and check for yourself or contribute to the RavenApp. SmartAir has a rundown of some monitors.
Air Purifiers
For indoor spaces where you have control (or influence) over the air quality, air purifiers with HEPA filters can be effective in lowering risk of transmission in the space.
There’s a review of some US brands at WireCutter , for those in Aus/NZ there’s Choice Magazine. As I update this (19 May 2024), the IKEA Starkvind is a good, cheap option for those in Australia.
If you don’t have a large budget, a Corsi Rosenthall box (a DIY air filter) is a cost effective alternative if you can get the parts cheaply where you are. As I update this (19 May 2024), the best prices on filters in Australia is buying the IKEA Starkvind replacement filters, while for Aotearoa New Zealand, your best bet is 3M filtrettes from Amazon.
I know what you’re thinking “a DIY air filter to clean virus out of the air, yeah right!”
Surprisingly, studies have found CR boxes to be both more effective and efficient at filtering the air than some commercial models.
For kids going into school or those going into an office space, a portable air filter is an option. This parent shared that their clinically vulnerable child uses a QT3 portable air filter in the classroom (as well as a mask) to protect them from COVID exposure. You may be able to find a local distributor of the QT3 for your country.
If you’re looking to suggest ventilation for a space you volunteer at or where your kids go, there’s this online calculator that helps you figure out how big and how many air purifiers are needed.
It now recommends DIY filters as well like The CorsiRosenthall boxes, or the quieter PC Fan CR boxes.
Note that Air Purifiers don’t take CO2 out of the air, so in a space using a purifier, the CO2 readings will remain high.
Vitamins and over the Counter Treatments
There is lots of information available and there’s many flawed but convincing studies available if you google things so it can be hard to discern information from misinformation.
The government funded Cochrane research network has set up a COVID website that provides publicly available information that is simple(ish) to digest on the latest research on COVID treatments and prevention.
Once again, I want to emphasise that this is not medical advice, I’m a software engineer, you should talk to your doctor about your health. For that reason, I’ve limited what I’ve looked at to over the counter products that are already commonly used and generally considered safe. That said, they may not be safe for you and your particular circumstances.
Note that the traffic lights on the Cochrane website are about the quality of the study, not the effectiveness of the treatment studied (eg they have some high quality studies that find certain treatments to be ineffective). You’ll have to click through to the studies to read the results and click into the traffic lights to see what concerns they had for the study.
Of the studies listed on their website for preventative & early treatment for COVID, the products that are over the counter and seem to improve outcomes are taking Zinc with Vitamin C, using a Povidone Iodine (aka Betadine) mouth spray and a big maybe on Iota Carrageenan in a nasal spray. Below I’ll go through each of these and link to the studies.
Vitamins
Based on the study examined by Cochrane, taking Zinc and Vitamin C regularly may help reduce risk of infection by 23% compared to taking only Vitamin C (which is already known to generally improve immunity). The subjects of the study took zinc and Vitamin C twice daily for a total of 80 mg zinc and 500mg vitamin C per day.
BLISK12 Probiotics (added 19 May 2024)
This is new and not from the Cochrane website, but I found it courtesy of Long Covid expert Dr Anna Brooks, and again, pro-biotics are over the counter.
A randomised control trial in Milan found that 51% of children taking a placebo got COVID, while 0% of those taking BLISK12 got it. The sample size is quite small so I don’t expect 100% effectiveness, but the result is still incredible.
Povidone Iodine (you probably know it as Betadine)
A mouth spray that contains Povidone Iodine showed a similar reduction (24%) of risk as Zinc + Vitamin C in the same study. Such sprays are not available everywhere, but there are mouthwashes that contain Povidone Iodine. The study participants used the spray 3 times a day.
However it’s worth noting that it might not be a good idea to use Povidone Iodine for long periods. Mouthwashes in general can disrupt the positive microbes and may have other harmful effects if used long term. So this is probably not something you want to be using on the daily as a preventative measure, but might instead be something you consider while you or someone in your house is COVID positive to reduce transmission risk.
It’s also possible that mouthwashes containing Cetylpyridinium Chloride may be effective in preventing the spread by temporarily killing COVID in the mouth, but Cochrane hasn’t investigated any studies of this that I could find.
Nasal Sprays
This comes with a maybe: The trial examined by Cochrane paired the Iota Carrageenan nasal spray with Ivermectin. Another study they examined found that Ivermectin did not significantly improve outcomes. It may be that the Iota Carrageenan only worked in conjunction or that it works on it’s own. There is also early research that suggests use of Iota Carrageenan nasal spray used alone may help prevent infection if used after exposure and may double the rate of recovery when already infected.
In the studies, the nasal spray was used 4 to 6 times a day.
So there’s still some uncertainty with this one. I feel ok including it here despite these caveats only because Iota Carrageenan is commonly used in food products and has been shown to be effective in reducing viral load in the common cold with few side effects observed.
Brushing Teeth
Carrageenan is also often used in toothpastes. While the study above used a particular form (Iota Carrageenan) and delivery method (nasal spray) and your toothpaste may use another form (Kappa Carrageenan), there’s probably little harm in doubling down on making sure you brush your teeth.
Stay Calm
Yes, I know this one is border line gaslighting. There’s a cost of living crisis and a virus out to get you. Governments are pretending that this is all fine.
Who would be calm?
It’s important to rest when you’re sick, and stress doesn’t help you rest. Some research has associated stress with a higher risk for long COVID.
So, if after the shitshow that has been the last two years, you’ve taken the time to read to the end of this article, and, despite huge social pressures to pretend it’s over, you are doing some of the things listed in this article, you’re doing a great job, don’t be too hard on yourself 👍
