https://arstechnica.com/science/2020/12 ... dangerous/
If you're unfortunate enough to breathe wildfire smoke, you’re getting a lungful of charred plant material, noxious gases, and—if the fire tore through human structures—incinerated synthetic materials. All across the board, it’s bad stuff, proven to be a severe detriment to human health, particularly for those with respiratory conditions like asthma. And not to pile on the worries, but that haze also turns out to be loaded with microbes like bacteria and fungi.
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When firefighters inhale this rotten air, the fungi can lead to a condition called coccidioidomycosis, or valley fever, with symptoms including fever and shortness of breath. The condition may progress to cause pneumonia or meningitis, an infection of tissues surrounding the brain and spinal cord. (Infection by another fungus genus called Cryptococcus, also a concern in wildfire smoke, leads to similar symptoms.) Coccidioidomycosis is common enough among firefighters that the Centers for Disease Control and Prevention considers the profession at-risk for the fungal infection.
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we know full well that the charred vegetation in smoke, known as particulate matter 2.5, or PM 2.5, can get deep into the lungs and cause major problems: the smoke decreases the antimicrobial activity of the cells, known as pulmonary macrophages, that clear the lungs of nasty microbes. Might the smoke’s PM 2.5 and microbes, then, work in cahoots, with the smoke clearing the way for the microbes to enter and harm the body? “Another aspect that is important to mention is the potential interaction between such potential infectious diseases transported through wildfire smoke and well-documented health impacts of PM 2.5 that constitute the smoke including a reduction of lung immunity (e.g. by reducing macrophages' activity),”
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