In the last blog post that I wrote about Covid in Chester County, I wrote that “the number of new cases reported on Friday, December 10, was 434. Although that is sure to be an extreme outlier and not a normal count going forward, I believe it represents a new record for our county.”

It turns out that I was wrong: it was not an outlier at all, but a harbinger of things to come.

The daily average number of new cases (618 on December 31) is already far higher than what I thought was an “outlier” only two weeks ago, and the most recent single-day count (also on December 31) was 1,002 cases. Chester County is seeing an average of 118 new cases every day per 100,000 of population.

In neighboring Delaware County, things look even worse. They are averaging 911 new cases per day, and on December 31, they had 1,573 new cases. Delaware County is reporting an average of 161 new cases per day, per 100,000 of population.

The charts of new cases for both counties are below. These charts, and the rest of the data in this blog post, are from the New York Times.

Seven-day average of new Covid cases for Chester County (left) and Delaware County (right). Note that the vertical scale is different for the two counties, and Delaware County has far more cases. Both charts are from the New York Times. I have added the annotations.

I count 28 states that have exceeded their peak from last winter. Seven states (if you include D.C. and Puerto Rico) have over twice their previous peak, and there is no sign yet that any state has passed its peak.

With the rise of Omicron, good masks and social distancing are more important than ever. But public health officials report that contact tracing has lost some of its value, because transmission is so rapid. If a person comes down with Omicron, by the time contact can be made with people who they may have exposed, those contacts may already have infected others.