Data Notes for the Week of October 8

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 continued to decline.  

Cases per day ranged from 85 to 163 with an average of 120 cases per day. Last week’s average number of cases per day was 139. In this 14-day period there were 1,677 total cases.

We define a cluster of cases as two or more cases associated with the same location around the same time. A recent example of this is an office building where staff have been working in person. One of the staff went to work while they were infectious with COVID, and then two of their coworkers subsequently also tested positive the following week.

Of the 1,378 non-UW cases in this 14-day period, 159 (12%) were associated with a cluster: 62 from less public-facing workplaces, 22 from congregate facilities, 16 from bars and restaurants, 11 from more public-facing workplaces, 10 from childcare facilities (7 children and 3 adults), 8 from a motorcycle rally, 7 from health care facilities, 7 from weddings, 5 from non-UW college-related clusters (including dorms and classes), 5 from sports teams, 2 from churches, 2 from funerals, and 2 from gyms.

A single case in a congregate living facility (e.g., long term care facilities, fraternities and sororities), a childcare facility, or a school initiates a facility investigation by our staff. A case “in” a facility means that the person who tested positive was in the facility while they were infectious. These types of facilities are prone to outbreaks and can contain vulnerable populations, and our case investigators work with them to ensure they are following best safety practices. The goal is to prevent a cluster of cases from occurring within the facility.

In this 14-day period, there were 13 schools (3 students and 10 staff), 10 childcare facilities (3 children and 7 adults), and 4 congregate facilities that had a single case but have so far prevented further spread from occurring.

Three schools outside of Dane County had a case from a Dane County resident (1 student and 2 staff) and also had one or more cases from non-Dane County residents, and it’s unknown whether transmission occurred within the school.

UW-Madison students and staff continue to make up a smaller proportion of Dane County cases, at 18% this period.

During this 14-day period, 267 UW students and 32 staff (299 total) tested positive, making up 18% of our total cases. This number was 76% from September 1 – 14.

Of the 299 UW cases in this 14-day period:

• 41 (14%) were linked to dorms
• 16 (5%) were linked to fraternities and sororities
• 72 (24%) were linked to apartment complexes on or near campus that have at least 10 or more cases
• 15 (5%) were associated with a non-housing cluster: 6 were from UW sports teams, 3 were from UW campus facilities such as dining halls, 3 were from restaurants and bars, and 3 were from other workplaces.

Note that these are not mutually exclusive: a student could, for example, live in a dorm but also be a member of a fraternity.

The 18-22 age group, which is representative of the UW student population age, is the only group that has fewer cases this week compared to last week. For cases outside the 18-22 age group, there has been a significant increase of 18% in the most recent 7-day period compared to the prior 7-day period.

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 lab timeliness and contact tracing metric continues to be red but is largely affected by lab timeliness.

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.

• During this period, 48% of cases were contacted by public health within 48 hours of being tested.
• 36% of positive tests were reported to us within 24 hours (up from 21% last week).
• 74% of cases were interviewed within 24 hours of receiving their test result (down from 78% last week).

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 number of patients hospitalized with COVID-19 in Dane County has increased, peaking at 60 hospitalizations on October 7.

This is a trend we are seeing statewide, including in the South Central region. 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.