Good morning Mission. And welcome to Virus Village, your daily data dump.
More on the fog of numbers.
San Francisco’s Department of Public Health announced yesterday that due to the glitch in the state’s reporting system for test results, it would “pause” in reporting contact tracing metrics. Although delays and undereporting impact what contact tracing can achieve, it shouldn’t impact on the numbers of known cases which can be traced and contacted.
San Francisco’s COVID-19 contact tracing program was launched with a great deal of promise. Since then the City has consistently reported that the program contacted between 80 to 85 percent of people who had tested positive and their contacts. Though below the goal of 90 percent, it still surpassed other cities and states. However, real numbers and information about how the program actually worked was spotty at best. A database has been promised for weeks, but never materialized. Less than half those trained were activated and worked in 4 hour shifts. Yesterday, before reporting stopped, the number of positive cases contacted over a two-week span fell to 73 percent.
Without a viable contract tracing program, people can run into all kinds of nightmares, as this recent op-ed in the New York Times relates. Grand Rounds on Thursday looked at why the U.S. has failed in its response to COVID – it’s telling because nothing has changed, and it appears we are doomed to keep failing.
And now onto our foggy numbers.
HiGeorge, a data visualization startup, developed some new visualizations for Mission Local, which we will be using and fine-tuning in the days to come.
The Mission now has 1019 reported cases, with 17 added from yesterday. We hear from those testing in the Mission District – at the Alabama hub and on 24th Street, positivity rates are between 7 to 9 percent, which demonstrates, at least, that the city is testing the populations that have been most impacted – Latinos account for 50 percent of the city’s cases.
Although we knew state reporting glitches affected California and Bay Area numbers, we thought San Francisco’s reporting was not affected because laboratories had been directed since March to report directly to the City. It turns out many did not follow the order, reporting their results to the state. Under-reporting of positive cases may have been going on since month. All labs have now been ordered by the state to report directly to the counties.
On July 31, the seven-day average of daily new cases was 93 approximately where it was yesterday and the day before. Some more cases were added to prior days, raising their average number from what we previously reported.
The R number is also affected by the daily case count in the state and in the counties. So the recent dip in the local R number may be somewhat illusory. Perhaps, rather than a specific number, it’s better to consider the range in which that number falls — between 1.05 and 1.27, which is consistent with other estimates. Either way you look at it, SF has the second highest number in the state, which means that although possibly more stable, the virus continues to spread.
Delays in obtaining test results mean the “more reliable” results come from a week ago. The seven day average for tests coming back positive on July 31 was 3.69 percent, about the same figure we’ve seen recently.
The state reporting issues should not affect hospitalization numbers, but we still do not have any updates on hospital bed availability. No data has been given since July 21. DPH does report another drop in the total number of COVID confirmed and suspected patients in SF hospitals to 94 as of August 5. The rate of weekly change in COVID positive patients, for the week ending 8/5 has decreased now by 18 percent.