San Francisco's Citywide COVID-19 Response: Strategies to Reduce COVID-19 Severity and Health Disparities, March 2020 Through May 2022.

San Francisco implemented one of the most intensive, comprehensive, multipronged COVID-19 pandemic responses in the United States using 4 core strategies: (1) aggressive mitigation measures to protect populations at risk for severe disease, (2) prioritization of resources in neighborhoods highly affected by COVID-19, (3) timely and adaptive data-driven policy making, and (4) leveraging of partnerships and public trust. We collected data to describe programmatic and population-level outcomes. The excess all-cause mortality rate in 2020 in San Francisco was half that seen in 2019 in California as a whole (8% vs 16%). In almost all age and race and ethnicity groups, excess mortality from COVID-19 was lower in San Francisco than in California overall, with markedly diminished excess mortality among people aged >65 years. The COVID-19 response in San Francisco highlights crucial lessons, particularly the importance of community responsiveness, joint planning, and collective action, to inform future pandemic response and advance health equity.

Contact-Tracing Outcomes Among Household Contacts of Fully Vaccinated Coronavirus Disease 2019 (COVID-19) Patients: San Francisco, California, 29 January-2 July 2021.

BACKGROUND: The extent to which vaccinated persons diagnosed with coronavirus disease 2019 (COVID-19) can transmit to other vaccinated and unvaccinated persons is unclear. METHODS: Using data from the San Francisco Department of Public Health, this report describes outcomes of household contact tracing during 29 January-2 July 2021, where fully vaccinated patients with COVID-19 were the index case in the household. RESULTS: Among 248 fully vaccinated patients with breakthrough infections, 203 (82%) were symptomatic and 105 were identified as the index patient within their household. Among 179 named household contacts, 71 (40%) contacts tested, over half (56%) were fully vaccinated and the secondary attack rate was 28%. Overall transmission from a symptomatic fully vaccinated patient with breakthrough infection to household contacts was suspected in 14 of 105 (13%) of households. Viral genomic sequencing of samples from 44% of fully vaccinated patients showed that 82% of those sequenced were infected by a variant of concern or interest and 77% by a variant carrying mutation(s) associated with resistance to neutralizing antibodies. CONCLUSIONS: Transmission from fully vaccinated symptomatic index patients to vaccinated and unvaccinated household contacts can occur. Indoor face masking and timely testing of all household contacts should be considered when a household member receives a positive test result in order to identify and interrupt transmission chains.

Prioritizing COVID-19 Contact Tracing During a Surge Using Chatbot Technology.

When COVID-19 cases surge, identifying ways to improve the efficiency of contact tracing and prioritize vulnerable communities for isolation and quarantine support services is critical. During a fall 2020 COVID-19 resurgence in San Francisco, California, prioritization of telephone-based case investigation by zip code and using a chatbot to screen for case participants who needed isolation support reduced the number of case participants who would have been assigned for a telephone interview by 31.5% and likely contributed to 87.5% of Latinx case participants being successfully interviewed. (Am J Public Health. 2022;112(1):43-47. https://doi.org/10.2105/AJPH.2021.306563).

"Is a Bird in the Hand Worth 5 in the Bush?": A Comparison of 3 Data-to-Care Referral Strategies on HIV Care Continuum Outcomes in San Francisco.

BACKGROUND: Health departments utilize HIV surveillance data to identify people with HIV (PWH) who need re-linkage to HIV care as part of an approach known as Data to Care (D2C.) The most accurate, effective, and efficient method of identifying PWH for re-linkage is unknown. METHODS: We evaluated referral and care continuum outcomes among PWH identified using 3 D2C referral strategies: health care providers, surveillance, and a combination list derived by matching an electronic medical record registry to HIV surveillance. PWH who were enrolled in the re-linkage intervention received short-term case management for up to 90 days. Relative risks and 95% confidence intervals were calculated to compare proportions of PWH retained and virally suppressed before and after re-linkage. Durable viral suppression was defined as having suppressed viral loads at all viral load measurements in the 12 months after re-linkage. RESULTS: After initial investigation, 233 (24%) of 954 referrals were located and enrolled in navigation. Although the numbers of surveillance and provider referrals were similar, 72% of enrolled PWH were identified by providers, 16% by surveillance, and 12% by combination list. Overall, retention and viral suppression improved, although relative increases in retention and viral suppression were only significant among individuals identified by surveillance or providers. Seventy percent of PWH who achieved viral suppression after the intervention remained durably virally suppressed. CONCLUSIONS: PWH referred by providers were more likely to be located and enrolled in navigation than PWH identified by surveillance or combination lists. Overall, D2C re-linkage efforts improved retention, viral suppression, and durable viral suppression.

Klebsiella pneumoniae K1 liver abscess and septic endophthalmitis in a U.S. resident.

Klebsiella pneumoniae K1 is a major agent of hepatic abscess with metastatic disease in East Asia, with sporadic reports originating elsewhere. We report a case of abscess complicated by septic endophthalmitis caused by a wzyAKpK1-positive Klebsiella strain in a U.S. resident, raising concern for global emergence.

The differential binding and activity of PRO 2000 against diverse HIV-1 envelopes.

OBJECTIVE: PRO 2000 is a polyanionic microbicide that binds directly to the glycoprotein 120 (gp120) envelope protein to inhibit HIV-1 entry. We studied the breadth of PRO 2000 activity against HIV-1 derived from recently transmitted R5 viruses. We also investigated the interaction of this compound with X4 and R5 HIV-1 envelope glycoproteins using an epitope-mapping strategy. METHODS: The anti-HIV activity of PRO 2000 against subtype B and C Env-pseudotyped viruses was assessed in saline and cervicovaginal lavage fluid. Competitive binding assays were performed with X4 and R5 monomeric and virus-associated gp120. RESULTS: PRO 2000 was found to be active against recently transmitted subtype B and C viruses tested in vitro, however, at 1 microg/mL in saline, activity against subtype C was decreased compared with subtype B. Epitope mapping using anti-V3 region antibodies showed that PRO 2000 binds to the V3 region of monomeric and virus-associated X4 gp120 with a higher affinity than to V3 of R5 gp120. In contrast, the interaction of PRO 2000 with the CD4-binding site was similar for both X4 and R5 monomeric and virus-associated gp120. CONCLUSIONS: PRO 2000 has significant activity against recently transmitted viruses, although some activity is lost at low concentrations. Epitope binding studies suggest that this broad activity is due to direct and indirect interactions with multiple gp120 sites rather than V3 binding alone.