DPH reports rising COVID-19 spread in San Francisco, pushes testing and neighborhood strategy

Director of Public Health Grant Colfax told the San Francisco Health Commission on Aug. 4 that the city was in a surge and that several indicators were cause for concern.

"Right now in San Francisco, we have nearly 7,000 cases of COVID-19," Colfax said, adding that the city had recorded 61 deaths to date and a seven-day testing average of about 3,118 tests per day. Colfax said the seven-day rolling positivity rate was running near 4 percent and that hospitalizations had climbed during July from a low of 26 in late June to a recent peak described in the slides (111) and a near-term figure given in the briefing (92), reflecting the lag between infection and hospitalization.

Colfax emphasized disparities in case distribution and a neighborhood-focused approach to testing. "We have inequities in the pandemic, particularly among the Latinx population who account currently for over a half of diagnosed cases," Colfax said, and outlined an adaptive testing plan to concentrate new testing resources in the census tracts with the highest prevalence.

Why it matters: city officials said that even modest shifts in the reproductive number could produce large differences in hospitalizations and deaths later in the year. Using the modeling presented to the commission, Colfax said the city's reproductive rate rose above 1 in mid-June and was estimated at about 1.15 at the time of the update; officials warned that remaining above 1 would continue to drive new hospitalizations.

What DPH will do next: Colfax said the department would expand low-barrier testing in high-prevalence neighborhoods and add two mobile sites (capacity ~250 tests/day each) plus a proposed permanent Southeastern site (capacity ~500/day). The department also said it was rapidly expanding contact-tracing capacity and aiming to return results more quickly through CityTestSF and the public health lab (CityTestSF turnaround targeted to about 72 hours).

Operational constraints and supply chain limits: Colfax told commissioners that turnaround times at some commercial labs had slipped to seven to 10 days and in reported cases up to two weeks, which weakens the value of testing for isolation and contact tracing. On supplies and equipment, Colfax said the city had about an 89 percent level of PPE needed to maintain a 30-day supply and reiterated the need for steady federal supply chains for reagents and other materials.

Close contacts and health orders: Colfax described the local health order requiring providers to test symptomatic people and close contacts (defined as unmasked contact for 15 minutes or more) within a 48-hour window and said DPH was coordinating with private systems to increase consistent, low-barrier testing for essential workers and vulnerable neighborhoods.

The Health Commission followed the presentation with questions about EHR compatibility, testing maps by census tract, and delays—and received reassurance that behavioral health work would be brought onto Epic in a later wave and that DPH would provide more granular testing data to commissioners.

What happens next: DPH will continue to monitor the reproductive rate, expand neighborhood testing resources, pursue improved lab turnaround times at CityTestSF, scale contact tracing and report back to the commission with updated data.