Williams faculty, staff and students,
Yesterday, while helping Deb Flynn, Marlene Sandstrom and Steve Klass write a campus announcement about our first confirmed COVID-19 case in the Williams community, I mischaracterized the risk of transmission from asymptomatic people. While paraphrasing the CDC’s position on this question, I wrote that “CDC guidelines regard the risk of contagion as very low when an individual is asymptomatic.” This is incorrect, and I apologize for my mistake. I also want to provide you with a more accurate picture of current thinking.
The CDC guidelines do downplay the risk of transmission from asymptomatic people. Here’s the quote from their “Transmission” page:
People are thought to be most contagious when they are most symptomatic (the sickest). Some spread might be possible before people show symptoms; there have been reports of this occurring with this new coronavirus, but this is not thought to be the main way the virus spreads.
There are two problems in how I summarized this statement.
First, what I wrote—that the CDC regards the risk of asymptomatic transmission as very low—mischaracterizes their point of view. Replacing the word “very” in my sentence with “relatively” would have kept it closer to the spirit of the original.
The second and more serious problem is that scientific consensus is shifting away from that position. Here’s how the New York Times described a finding from a new report in the journal Science last week: “On average, [asymptomatic individuals] are about half as infectious as confirmed ones, but they are responsible for transmitting the virus in nearly 80 percent of new cases.” That’s a very different analysis, for statistical reasons: asymptomatic individuals may be less infectious, but are more likely to continue interacting freely with, and potentially infecting others than are their symptomatic counterparts. This is exactly why vigilant social distancing is so important even when one doesn’t feel sick.
It’s a substantive difference from what I wrote, and it’s directly relevant to the case we were informing you of yesterday, in which a person who was on our campus overnight was later confirmed positive but remains asymptomatic a week later.
I asked Maud’s permission to apologize to you all. My colleagues and I are working hard to be candid in our communications, and it pains me to have been the source of incorrect information. I’m sorry, and will strive to make sure it doesn’t happen again.
To anticipate a likely next question: as stated in yesterday’s message, public health officials did indeed tell our Director of Medical Services Deb Flynn that exposure to an asymptomatic individual who has received a positive test result doesn’t by itself qualify someone for testing under current regional criteria. Deb and many of us would like to see those criteria expanded, and we’ll advocate for changes whenever we get the opportunity. We’ll inform you if the criteria evolve.
I’m also now able to share, in regards to questions we’ve received, that the “community member” who tested positive while asymptomatic is a student who wasn’t enrolled on campus during the spring semester. The student has told us that they were only on campus from Saturday, March 14, through Sunday, March 15, a statement backed up by other facts.
In closing, I want to thank the Williams faculty, parents and staff members who brought the error to our attention and offered suggestions that enabled me to correct it. I know this new message won’t allay concerns about the case reported yesterday. That’s why we’re going to keep you informed about any potential risk based on current scientific consensus. Meanwhile, I appreciate you helping make sure the college shares accurate and reliable information under difficult circumstances.
Chief Communications Officer