Individual Preparedness for Distant Wildfires and the Delta Variant in the United States: A Survey of 2,250 US Residents

BackgroundCOVID-19 virus travels in the air and collects indoors through tiny particles from exhaled breath, and remains a growing concern globally especially since case studies of vaccine breakthrough infections are being reported. Last years wildfires resulted in the worst air quality on record in the Western US due to toxic wildfire smoke (PM 2.5 pollution) traveling from distant wildfires and this year can potentially be even worse due to extremely dry conditions. Aerosol precautions such as high-filtration (Hi-Fi) masks and HEPA air purifiers are useful to effectively reduce inhalation of most of these toxic aerosols. Whereas the lack of fit or filtration in a mask or use of an air purifier of insufficient size (capacity) for the room can inadvertently render these precautions ineffective. Here we investigate the publics concerns about wildfires and the COVID-19 variants (e.g. delta), their use of aerosol precautions, and whether these are being done in an effective manner. MethodsWe conducted a national survey of 2,250 US residents in order to understand public concerns about airborne threats and their usage of airborne (aerosol) precautions. ResultsWe find over 66% of US residents surveyed are worried about inhaling COVID-19 and its variants, and 52% are worried about toxic wildfire particles in the air. In the mountain and pacific regions the latter rises to 73%. Only a quarter are using masks with higher filtration and high level of fit (or Hi-Fi masks e.g. N95 or similar such as elastomeric N95 or KF94). Two-thirds are still using loose-fitting cloth or surgical masks. Just over 40% of respondents report using air purifiers at home, and of this group only 40% use it in their bedroom where they sleep. Of those using air purifiers, the majority said they chose the size of their air purifier based on "most popular" models, "recommendations," or "reviews." However, of those using air purifiers only 42% reported doing a calculation (or using a calculator) to estimate the right size of air purifier needed for the room they are using it in. Notably, a much higher percentage of people (than average) reported use of Hi-Fi masks and home air purifiers in certain occupations such as doctors, healthcare, first responders, public safety, engineering, military, and construction. ConclusionNational survey data suggests most US residents are worried about wildfire smoke and Covid variants (e.g. delta variant) but a majority are not prepared for it. Preparation with aerosol precautions will also be useful for future pandemics and national biodefense.