The current theory is that viral load is a factor in the severity of your infection. If you are exposed to it often and in larger quantities, you get a more sev

The current theory is that viral load is a factor in the severity of your infection. If you are exposed to it often and in larger quantities, you get a more severe infection. Therefore, healthcare workers are more likely to get a severe infection. For example, the nursing home workers in Seattle were using CPAP machines on their patients that aerosolized the virus and exposed them all to large amounts of the virus. Theory also applies to subway riders, as outbreaks appear far more severe in areas that rely on public transport with NYC infections following the subway stops with a relatively high correlation.