What the Spurs can teach us about COVID-19 Response
How many of us San Antonio Spurs fans know the heartbreak of being so close to the victory, only to have it snatched from our grasp at the final buzzer?
San Antonio’s COVID-19 situation feels a bit like a 3rd Quarter rain of threes, pulling out ahead of the Lakers, the Heat, the Mavs.
There has been much excitement locally as Bexar County’s COVID-19 cases continue to decrease. This is great news. Hospitals have more capacity, ICUs are no longer at their limits, everyone can breathe a bit.
We can, and should, celebrate this stage. But don’t wheel out the Larry O’Brien trophy just yet.
If you followed my writings in March, April, and even May, I focused on the positive. But we must be very cautious with our optimism. It all hinges on public health infrastructure.
Dr. Tom Frieden is the former head of the Centers for Disease Control and current CEO of Resolve to Save Lives, “A global health initiative with Vital Strategies that aims to save 100 million lives from cardiovascular disease and prevent epidemics.” Their website, PreventEpidemics.org has a global alert system based on a series of indicators.
Based on Resolve to Save Lives’ indicators, declining cases are important, but more important is the threshold. While some articles about school opening propose different thresholds, because COVID-19 is a new disease, we don’t have a standard national threshold.
And that matters.
The group has defined the threshold between Level 3 and Level 4 as 40 new cases per 1 Million people per day. In Bexar County, new cases are declining, but by that standard, we’ve been in the Red since late May. May, when locally we opened every thing and tried to get back to normal. The first jump above 100 new cases in a day happened on June 6. It dropped again, then by June 9, continued to climb steeply.
While it’s only obvious in retrospect, those “few” cases in May were already creeping upwards. As of August 29, Bexar County is still above the threshold with an average of 81 new cases per 1 million per day this past week.
To contain, mitigate, and suppress COVID-19, our health care system must have the capacity to respond to critical cases. In June and July, hospital capacity dropped dangerously low, but it’s been on the upswing. According to the mayor in the briefing on Aug 29, we currently have 14% of staffed hospital beds available and 64% of ventilators. ICU capacity is not given, but we are down from a peak of 438 ICU beds filled on July 15, to 179 now. We are moving in the right direction. We’re not out of the woods yet.
This still falls short of the recommended hospital capacity of > 20%. Their use of healthcare worker infections is a useful indicator. Presumably our hospitals have these data and are reviewing it internally, incorporating it into the overall stress on the healthcare system indicators.
San Antonio’s current positivity rate, 9.9%, puts us in the Green. But we must remember that any rate is dependent upon the denominator. While fewer tests can skew towards a higher positivity rate if we’re only testing the most ill, the rate can also skew the other direction if we’re not testing a broad cross section of the community, to include high risk populations and marginalized populations. (We may be, we probably are, we don’t know that yet, we’re looking to verify.) A strong denominator gives us more confidence in our positivity rate. In July, Bexar County was testing anywhere from 1,000–5,000 per day.
The other Disease Control measure, contact tracing, is a little harder to calculate.
“Fundamentally, contact tracing is about people helping people,” says Tom Frieden, in this article about technology and the best public health approach to fighting the pandemic. “Contact tracing is about building a human bond between someone who wants to help and support patients and their contacts, and society more broadly.”
[A note on “Contact Tracing:” Disease investigation typically includes case investigation AND contact tracing. Nationally, the term “Contact Tracing” has been used in place of “Disease Investigation.” Locally, Case Investigation and Contact Tracing are distinct, discreet activities. The city conducts Case Investigations, then turns the information obtained over to MTX, who conduct the contact tracing.]
There are Four Steps to Contact Tracing :
Identify and notify cases of their confirmed or probable COVID-19 status. Provide instructions on isolation and treatment.
Interview cases and help them identify the people they were in contact with during their infectious period.
Locate and notify contacts of their potential exposure, interview them to see if they have symptoms, offer testing if they do (and if they don’t), and arrange for care if they are ill. Provide instructions on quarantine.
Monitor contacts and report daily on each person’s symptoms and temperature for 14 days after the person’s last contact with the patient while they were infectious.
While the surge in cases in June and July overwhelmed the capacity to investigate all cases, currently, the city is investigating 100% of the lab reports less than 14 days old. (If older than 14 days, they’re not investigated.) However, the final two steps, Locate and Notify contacts and Monitor contacts are done by MTX, the company contracted by Governor Abbott.
There are as of yet no publicly available data on numbers of contacts reached, numbers of contacts tested, tracing of those contacts, outcome of contact tracing investigations, etc.
In March, Dr. Frieden’s group developed guidelines for public health infrastructure. When we’re in a surge, as we were in June and July, it can be impossible to Suppress or Contain the spread. Extensive testing and contact tracing may suffer. As the number of new cases become more manageable, extensive testing and contact tracing become even more critical.
In an outbreak, it is normal to see waves. Cases will begin to decline. It’s what we do when they are declining that determines whether the next wave will be worse than the first. In the graphic above, the second and third waves appear as small “blips.” That will only happen if all of the elements listed in the graphic are operating at full capacity.
We want schools to open, we want businesses open. We want life to go back to normal. We can do some of that, cautiously, slowly, only if all the essential public health infrastructure is in place to address cases at our highest point. As we saw in May and June, blink and we go from less than 50 cases per day to many hundreds.
It’s tempting, when things are looking better, to relax. If Bexar County was the Spurs, we’re up by 6 points with 2 minutes left in the NBA Finals. We can’t celebrate until the final buzzer, and that may not go off for another year.
For more on the indicators and alerts: