N95 masks might claim ?95% filtration with 0.3 micron particles, but realistically most people don't wear masks with proper fitting. The mask needs to be sized and fitted correctly to form a seal. However even poorly fitted masks will reduce the viral load when inhaled. By reducing the viral load, you reduce the infection rate and severity.
For airborne transmission via aerosol particles, the particles will generally settle downward within 30 mins. If you do your shopping in early mornings with few other customers, you can reduce the risk. Avoid smaller enclosed spaces, such as indoor restaurant with A/C where the aerosol particles could stay airborne for hours and spread 20-30 ft distance.
Moderna is currently working on a booster shot targeting COVID-19 strain B.1.1.7 (UK) and B.1.351 (SA). Existing Moderna vaccine also offers some protection:
https://www.cnbc.com/2021/01/25/cov...d-booster-shots-for-south-african-strain.html
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There is a lot of uncertainty regarding new viral strains. It's possible that we may get hit with one that makes you want to stay home, and avoid in-person contact for weeks until new booster shots are avail.
It's a good idea to prep a supply of food, water, and medicine at home. You don't need to buy expensive "survival rations". Most canned foods have shelf life of 2-5+ years, and your local discount retailer is a great place to stock up.
When purchasing emergency supply food, consider the following:
* Do you actually enjoy eating it? If you hate canned sardines don't buy it. Under normal (non-emergency) conditions, use a few canned foods weekly and replace them with fresh cans.
* Check the expiration or best used by date. Preferably it should have 2-5+ years shelf life remaining for canned food, or at least a year for boxed food, seasonings, etc.
* Check the content and nutritional value of the food. If it has less nutritional value than Kool-aid (empty calories), you should probably look for something else.
* The food should be shelf stable, does not require refrigeration, and ready to heat/consume. If you're buying stuff that requires cooking, consider if the ingredients will be readily avail at home.
* Make a budget and buy a variety of canned and bagged/boxed foods. If you really love Campbell's canned soup and can eat it every day for a month, by all means go for it. For rest of us have a variety so you won't get bored/depressed.
* Don't forget to stock multivitamins, canned fruit, milk/beverage powders, and seasonings. A drink of hot cocoa makes many problems go away for the night. Taco seasoning and (powdered) gravy can be mixed with many foods.
* Be creative! You can add canned chicken, spam, etc. to Mac and Cheese to make a casserole.