By: Pepper Fisher
SEATTLE – A new report from Seattle’s Fred Hutchinson Cancer Research Center finds that 80% of those who test positive for Covid-19 never infect anyone else with the virus. That may come as a surprise since the number of cases in the US is nearing 5 million and showing no signs of slowing.
But the research suggests the virus makes up for the relatively small percentage of people who spread the disease by taking advantage of people who are what they call “super-spreaders”, or people who, for a couple of days, are highly contagious but don’t know it.
It appears that for many, but not all infected people, the two-day contagious period may have ended before the person felt any symptoms, and that before then, the person may already have spread the virus to dozens of others.
While they’re at it, the researchers at Fred Hutch are comparing the behavior of COVID-19 with influenza. They found that both influenza and COVID-19 share this brief contagious period in common. But coronavirus may be more prone to super-spreading because of airborne transmission, which makes it much more dangerous in crowded, confined spaces.
The six-foot rule for social distancing springs from evidence that COVID-19 spreads in droplets that can travel only short distances before settling to the ground. Airborne transmission envisions the virus can be carried in tinier particles of moisture that hang in the air longer and can drift across a room, a theory that not all health experts agree on.
One of the researchers, Dr. Joshua T. Schiffer, wrapped it up like this, “The ethical thing to do as an individual is to walk around with the assumption that you’re infectious and contagious, and that it’s your responsibility to protect the public. That doesn’t change at all”.