Data Notes for the Week of November 5

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 (data from October 20—November 2):

Dane County’s 14-day average number of cases continues to increase and is currently at 277 cases per day, up from 214 in the last snapshot.

Cases per day ranged from 127 to 378 with an average of 277 cases per day. In this 14-day period there were 3,879 total cases. 513 (13%) of these cases were associated with a cluster and/or a facility investigation.

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 35 total workplace, not public-facing facility investigations. Overall, there were 69 cases associated with this category.

During this two-week period, the overall rate of cases in Dane County was 71 cases per 10,000 population. Nine 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, this number 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 71 cases per 10,000 population. Another way of saying this is 50.7 cases per 100,000 per day. Nine municipalities in Dane County had rates that were significantly higher than the overall rate: Marshall, Brooklyn, Town of Dane, Waunakee, Deforest, Deerfield, Sun Prairie, Cottage Grove, and Monona. Please note that if a municipality straddles multiple counties, the number of cases and the population are for Dane County residents only. 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 increased to 6.0% and remains yellow.

Percent positivity for this period was 6.0%, up from 5.0% last week. Dane County has 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.

There was a statistically significant increase in COVID-like syndromic cases, and this metric turned red.

As defined by the Department of Health Services, these are emergency department visits for people with COVID-like symptoms, whether or not they are tested or test positive, and these can be an early warning indicator for future hospitalizations. A portion of emergency department visits will become hospitalized, so with an increasing number of emergency department visits for COVID-like symptoms, an increasing number of hospitalizations with COVID-19 could follow.

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, 19% of cases were contacted by public health within 48 hours of being tested, down from 26% last week.
• 52% of positive tests were reported within 24 hours.
• 22% of cases were interviewed within 24 hours of when their positive test was reported.
• 66% 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 142 hospitalizations on November 2.

In the past two weeks, the number of patients hospitalized with COVID-19 in Dane County has increased, peaking at 142 hospitalizations on November 2. The peak last period was 119 hospitalizations.

2% of cases in this 14-day period were hospitalized. The risk of being hospitalized increases with age: 14% of cases age 70+ were hospitalized while 1% of cases age 23-69 were hospitalized.

The South Central Region has a growing trajectory for COVID patients hospitalized and COVID patients in the ICU. Increases in hospitalizations are concerning because strained health care systems may struggle to meet the needs of all patients.

Looking Ahead

As we shared last week, 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.