Data Notes for the Week of October 29

Today we released this week’s data snapshot. If you’re new to the data snapshot, we publish a weekly summary of the status for each of our metrics (you can find past issues on our data and metrics page). We have a few notes for this week’s issue:

Dane County’s 14-day average number of cases has increased again and is currently 214 cases per day.  

Cases per day ranged from 120 to 316 with an average of 214 cases per day. Last week’s average number of cases per day was 167.

In this 14-day period there were 2,992 total cases. 404 (14%) of these cases were associated with a cluster and/or a facility investigation. As COVID becomes more widespread, larger numbers of cases associated with clusters are expected. We define a cluster of cases as two or more cases associated with the same location or event around the same time. A facility investigation is initiated when there is evidence of a cluster of cases or a strong possibility for a cluster to emerge from a single facility or setting. To learn more about clusters and facility investigations, see our recent blog post!
 

^Most clusters also receive a facility investigation, e.g., there were 28 total workplace, not public-facing facility investigations. Overall, there were 54 cases associated with this category.

During this two-week period, the overall rate of cases in Dane County was 55 cases per 10,000 population. Ten municipalities in Dane County had rates that were significantly higher than the overall rate.

In September (at the peak of the UW outbreak), 28% of cases resided outside of Madison; in October so far, this number has increased to 56%. COVID-19 is spreading everywhere in Dane County, which is why it’s so important for everyone to follow all precautions at all times, no matter where you live.

During this two-week period, the overall rate of cases in Dane County was 55 cases per 10,000 population. Ten municipalities in Dane County had rates that were significantly higher than the overall rate: Cambridge, Brooklyn, Marshall, Town of Dane, Waunakee, Deerfield, Deforest, McFarland, Stoughton, and Sun Prairie. We are seeing increased numbers of cases in nearly every Dane County municipality.

The recommended target for grades 3-5 was not met this week.

The K-12 school metrics are detailed on our website. The Wisconsin Supreme Court issued an injunction that allows K-12 schools in Dane County to fully open for in-person instruction. We are disappointed in this decision and strongly urge all schools to continue voluntary phasing-in of classes for in-person instruction for grades 3-12. We will continue to update data weekly and advise schools on their reopening plans.

The percent positivity metric turned yellow, at 5.0%.

Percent positivity for this period was 5.0%, up from 3.9% last week. Dane County had steadily increased testing each week so we expected more cases, but the increase in cases far outpaced the increase in testing. This means we know the increase in cases isn't solely from more testing. An increase in percent positivity can indicate more widespread infection, so more testing is needed to capture all cases.

The lab timeliness and contact tracing metric dropped again.

Lab timeliness (how quickly labs are reported to us) and contact tracing (how quickly we can reach out to cases) are combined into one metric because lab timeliness directly affects contact tracing. The struggle to keep up with contact tracing is clearer in this week’s metrics and support why we needed to move to a crisis model of contact tracing.

• During this period, 26% of cases were contacted by public health within 48 hours of being tested, down from 36% last week.
• 65% of positive tests were reported within 24 hours of when the test was collected
• 26% of cases were interviewed within 24 hours of when their positive test was reported
• 77% of cases have been successfully contacted so far (not necessarily within 24 hours)

The number of patients hospitalized with COVID-19 in Dane County has increased, peaking at 119 hospitalizations on October 28.

Hospitalizations continue to increase, peaking at 119 hospitalizations on October 28. A little under a month ago, on September 29, we were at 37 hospitalizations. We continue to see this upward trend in the South Central region and in all of Wisconsin. We are monitoring hospitalizations very closely because increases in hospitalizations can lead to a strained healthcare system that struggles to meet the needs of all patients. In a recent press conference, Dr. Nasia Safdar from UW Health said,

“The bottom line is things are far worse than they were even just a few days ago, and we seem to be on a fast increasing trajectory, in not a favorable direction."

Looking Ahead

Every day more research is released that gives clues about how COVID-19 is transmitted and strategies that have been effective in reducing spread. Public Health Madison & Dane County staff continue to review this research, the latest metrics and indicators, and best practices issued from state and federal agencies.

As we assess this new information, it could inform changes to the metrics in the future. As always, we will keep the community informed of any changes and how they affect our future response to this virus.