Effectiveness of a fourth dose of mRNA-1273 against COVID-19 among older adults in the United States: Interim results from an observational cohort study.

We evaluated relative vaccine effectiveness (rVE) of 4- vs. 3-dose mRNA-1273 against SARS-CoV-2 infection, and COVID-19 hospitalization and death in immunocompetent adults aged ≥50 years at Kaiser Permanente Southern California. We included 178,492 individuals who received a fourth dose of mRNA-1273, and 178,492 randomly selected 3-dose recipients who were matched to 4-dose recipients by age, sex, race/ethnicity, and third dose date. Adjusted 4- vs. 3-dose rVE against SARS-CoV-2 infection, COVID-19 hospitalization, and COVID-19 hospitalization death were 25.9 % (23.5 %, 28.2 %), 67.3 % (58.7 %, 74.1 %), and 72.5 % (-35.9 %, 95.2 %), respectively. Adjusted rVE against SARS-CoV-2 infection ranged between 19.8 % and 39.1 % across subgroups. Adjusted rVE against SARS-CoV-2 infection and COVID-19 hospitalization decreased 2-4 months after the fourth dose. Four mRNA-1273 doses provided significant protection against COVID-19 outcomes compared with 3 doses, consistent in various subgroups of demographic and clinical characteristics, although rVE varied and waned over time.

Vaccine effectiveness of the mRNA-1273 3-dose primary series against COVID-19 in an immunocompromised population: A prospective observational cohort study.

BACKGROUND: Data on the effectiveness of the 3-dose mRNA-1273 primary series are limited, particularly in comparison to 2 doses. Given suboptimal COVID-19 vaccine uptake among immunocompromised populations, it is important to monitor the effectiveness of fewer than the recommended doses in this population. METHODS: We conducted a matched cohort study at Kaiser Permanente Southern California to evaluate the relative vaccine effectiveness (rVE) of the 3-dose series vs 2 doses of mRNA-1273 in preventing SARS-CoV-2 infection and severe COVID-19 outcomes among immunocompromised individuals. RESULTS: We included 21,942 3-dose recipients who were 1:1 matched with randomly selected 2-dose recipients (third doses accrued 08/12/2021-12/31/2021, with follow-up through 01/31/2022). Adjusted rVE of 3 vs 2 doses of mRNA-1273 against SARS-CoV-2 infection, COVID-19 hospitalization, and COVID-19 hospital death were 55.0 % (95 % CI: 50.8-58.9 %), 83.0 % (75.4-88.3 %), and 87.1 % (30.6-97.6 %), respectively. CONCLUSION: Three doses of mRNA-1273 were associated with a significantly higher rVE against SARS-CoV-2 infection and severe outcomes, compared to 2 doses. These findings were consistent across subgroups of demographic and clinical characteristics, and mostly consistent across subgroups of immunocompromising conditions. Our study highlights the importance of completing the 3-dose series for immunocompromised populations.

Decision-Making about COVID-19 Vaccines among Health Care Workers and Their Adolescent Children.

Health care workers promote COVID-19 vaccination for adolescent patients, and as parents, may influence their own children to get vaccinated. We conducted virtual, semi-structured qualitative interviews with vaccinated health care workers and their adolescent children to explore their decision-making process for COVID-19 vaccination. In total, 21 health care workers (physicians, nurses, and medical staff) and their adolescent children (N = 17) participated in interviews. The following three themes described parent-adolescent decision-making for COVID-19 vaccination: (1) family anticipation and hesitation about COVID-19 vaccine approval; (2) parents' or adolescents' choice: the decision maker for adolescent COVID-19 vaccination; and (3) leveraging one's vaccination status to encourage others to get vaccinated. Nurses encouraged adolescent autonomy in decisions for COVID-19 vaccination while physicians viewed vaccination as the parent's decision. Health care workers and their adolescent children used role-modeling to motivate unvaccinated peers and may model their decision-making process for adolescent COVID-19 vaccination with their own children to support their patients' and parents' vaccine decisions.

Effectiveness of pneumococcal conjugate vaccination against virus-associated lower respiratory tract infection among adults: a case-control study.

BACKGROUND: Interactions of Streptococcus pneumoniae with viruses feature in the pathogenesis of numerous respiratory illnesses. METHODS: We undertook a case-control study among adults at Kaiser Permanente Southern California between 2015-2019. Cases were diagnosed with lower respiratory tract infection (LRTI; including pneumonia or non-pneumonia LRTI diagnoses) with viral infections detected by multiplex polymerase chain reaction testing. Controls without LRTI diagnoses were matched to cases by demographic and clinical attributes. We measured vaccine effectiveness (VE) for PCV13 against virus-associated LRTI via the adjusted odds ratio of PCV13 receipt, comparing cases to controls. RESULTS: Primary analyses included 13,856 virus-associated LRTI cases and 227,887 matched controls. Receipt of PCV13 was associated with 24.9% (95% confidence interval: 18.4-30.9%) VE against virus-associated pneumonia and 21.5% (10.9-30.9%) VE against other (non-pneumonia) virus-associated LRTI. We estimated 26.8% (19.9-33.1%) and 18.6% (9.3-27.0%) VE against all virus-associated LRTI episodes diagnosed in inpatient and outpatient settings, respectively. We identified statistically-significant protection against LRTI episodes associated with influenza A and B viruses, endemic human coronaviruses, parainfluenza viruses, human metapneumovirus, and enteroviruses, but not respiratory syncytial virus or adenoviruses. CONCLUSIONS: Among adults, PCV13 conferred moderate protection against virus-associated LRTI. Impacts of PCVs may be mediated, in part, by effects on polymicrobial interactions between pneumococci and respiratory viruses.

Race/Ethnicity Differences in COVID-19 Vaccine Uptake Among Nurses.

INTRODUCTION: There is evidence for relatively lower COVID-19 vaccine uptake among people of color in the United States. The purpose of this study was to investigate associations between race/ethnicity and COVID-19 vaccine uptake among nurses. METHODS: Nurses in Southern California (N = 1183) completed a one-time, web-based survey to assess COVID-19 vaccine perceptions and uptake. RESULTS: In all, 82.8% of respondents (N = 979) received at least one COVID-19 vaccine dose. Identifying as East Asian was associated with 14% higher odds of COVID-19 vaccine uptake relative to identifying as White (odds ratio [OR] = 1.14/95% confidence interval [CI] = [1.06, 1.24]); identifying as Filipino was associated with 14% higher odds of uptake (OR = 1.14/95% CI = [1.08, 1.20]); and identifying as Hispanic/Latinx was associated with 6% higher odds of uptake (OR = 1.06/95% CI = [1.00, 1.12]). DISCUSSION: Although nurses and people of color have been identified as groups with low levels of COVID-19 vaccine uptake, this study found that nurses of color received the vaccine at higher levels than their White counterparts.

COVID-19 vaccine concerns of health care providers and ancillary staff.

A web-based survey was widely distributed between November 1st-December 27th, 2021, to health care providers and ancillary staff to assess reported COVID-19 vaccination of their children as well as their vaccine concerns. Fewer nurses and laboratory / radiology technicians reported COVID-19 vaccination of their adolescent children and intent to vaccinate their younger children compared to physicians and pharmacists, along with more frequently reported concern about anaphylaxis and infertility. Focused efforts to update ancillary staff as well as all health care providers on emerging COVID-19 vaccine safety information for children is crucial to promote strong COVID-19 vaccine recommendations. IMPACT: Nurses, laboratory technicians and radiology technicians frequently reported concern about anaphylaxis and infertility after COVID-19 vaccination despite reassuring safety data. Education of ancillary staff with emerging safety data is important to strengthen health care provider vaccine recommendations.

Anakinra or high-dose corticosteroids in COVID-19 pneumonia patients who deteriorate on low-dose dexamethasone: An observational study of comparative effectiveness.

OBJECTIVE: To assess whether escalating to high-dose corticosteroids or anakinra compared to continuing low-dose corticosteroids reduced mortality in patients with severe coronavirus disease 2019 (COVID-19) whose respiratory function deteriorated while receiving dexamethasone 6mg daily (DEXA6). METHODS: We conducted a retrospective cohort study between 3/1-12/31/2020 of hospitalized patients with confirmed COVID-19 pneumonia. In-hospital death was analyzed using logistic regression with inverse probability of treatment weighting of receiving anakinra, high-dose corticosteroid (dexamethasone >10mg daily) or remaining on low-dose corticosteroids on the day of first respiratory deterioration. RESULTS: We analyzed 6,671 patients whose respiratory status deteriorated while receiving DEXA6 for COVID-19 pneumonia, of whom 6265 stayed on low-dose corticosteroids, 232 were escalated to high-dose corticosteroids and 174 to anakinra in addition to corticosteroids. The propensity score-adjusted odds of death were higher in the anakinra (odds ratio [OR]=1.76, 95% CI=1.13-2.72) and high-dose corticosteroid groups (OR=1.53, 95% CI=1.14-2.07) compared with those who continued low-dose corticosteroids on the day of respiratory deterioration. The odds of hospital-acquired infections were also higher in the anakinra (OR=2.00, 95% CI=1.28-3.11) and high-dose corticosteroid groups (OR=1.43, 95% CI=1.00-2.04) compared with low-dose corticosteroid group. CONCLUSION: Our findings do not support escalating patients with COVID-19 pneumonia who deteriorate on low-dose corticosteroids to high-dose corticosteroids or anakinra.

Effectiveness of mRNA-1273 vaccine booster against COVID-19 in immunocompetent adults.

BACKGROUND: A prospective cohort study at Kaiser Permanente Southern California was conducted to evaluate the relative vaccine effectiveness (rVE) of a booster-dose vs. 2-dose primary series of mRNA-1273 in immunocompetent individuals during periods of Delta and Omicron predominance. METHODS: Immunocompetent adults who received a booster dose of mRNA-1273 from October through December 2021 were matched 1:1 to randomly selected 2-dose mRNA-1273 recipients by age, sex, race/ethnicity, and second dose date, and followed up through January 2022. Cox proportional hazards models were used to estimate adjusted hazard ratios (aHR) with 95% confidence intervals (CIs), comparing outcomes (SARS-CoV-2 infection, and COVID-19 hospitalization and hospital death) in the booster-dose and 2-dose groups. Adjusted rVE (%) was calculated as (1-aHR)x100. aHRs and rVEs were also estimated for SARS-CoV-2 infection by subgroups (age, sex, race/ethnicity, history of SARS-CoV-2 infection, pregnancy, chronic diseases), and for SARS-CoV-2 infection and severe COVID-19 disease by month of follow-up. RESULTS: The study included 431,328 booster-dose vaccinated adults matched to 431,328 2-dose vaccinated adults. rVE was 61.3% (95%CI: 60.5-62.2%) against SARS-CoV-2 infection, 89.0% (86.2-91.2%) against COVID-19 hospitalization, and 96.0% (68.0-99.5%) against COVID-19 hospital death. rVE against SARS-CoV-2 infection ranged from 55.6% to 66.7% across all subgroups. rVE against SARS-CoV-2 infection decreased from 67.1% (0-<1 month of follow-up) to 30.5% (2-<3 months). For COVID-19 hospitalization, rVE decreased from 91.2% (0-<1 month) to 78.7% (2-<3 months). CONCLUSIONS: Among immunocompetent adults, the mRNA-1273 booster conferred additional protection against SARS-CoV-2 infection and severe COVID-19 disease compared to the 2-dose mRNA-1273 primary series during periods of Delta and Omicron predominance.

The intensity of anticoagulant dosing in hospitalized patients with COVID-19: An observational, comparative effectiveness study.

BACKGROUND: The question of anticoagulant dosing in hospitalized patients with coronavirus disease-2019 (COVID-19) is unresolved, with randomized trials showing mixed results and heterogeneity of treatment effects for in-hospital death. OBJECTIVE: To examine the association between the intensity of anticoagulation and clinical outcomes in hospitalized patients with COVID-19. DESIGN, SETTING AND PARTICIPANTS: Retrospective cohort study of patients with COVID-19 and respiratory impairment who were hospitalized between 3/1/2020-12/31/2020 in two Kaiser Permanente regions. EXPOSURE AND MAIN OUTCOME: We fit propensity score models using categorical regression to estimate the probability of receiving standard prophylactic, intermediate, or full-dose anticoagulation beginning on the day of admission or on the day of first respiratory deterioration. Exposure was defined by the highest dose on the day of admission or within 24 hours after deterioration. The primary outcome was in-hospital death. RESULTS: We included 17,130 patients in the day of admission analysis and 4,924 patients who experienced respiratory deterioration. There were no differences in propensity score-adjusted odds of in-hospital death for patients who received either intermediate (odds ratio [OR]: 1.00, 95% confidence intervals [CI] 0.89-1.12) or full anticoagulation (OR: 1.00, 95% CI: 0.85-1.17) compared with standard prophylaxis beginning on the day of admission. Similarly, there were no differences in in-hospital death for either intermediate (OR: 1.22, 95% CI: 0.82-1.82) or full anticoagulation (OR: 1.50, 95% CI: 0.90-2.51) compared with standard prophylaxis on the day of deterioration. CONCLUSION: Results of this real-world, comparative effectiveness study showed no differences in in-hospital death among newly admitted or deteriorating patients with COVID-19 who received intermediate-dose or full anticoagulation compared with standard prophylaxis.

Adolescent Self-Consent for COVID-19 Vaccination: Views of Healthcare Workers and Their Adolescent Children on Vaccination Autonomy.

PURPOSE: This study explored the perceptions of healthcare worker parents (physicians, nurses, and staff) and their adolescents (aged 12-17 years) on adolescent self-consent to COVID-19 vaccination by applying the concept of positive deviance of those already vaccinated against COVID-19. METHODS: We used a qualitative descriptive design to conduct individual, semi-structured interviews with COVID-19-vaccinated healthcare workers in Southern California and their vaccinated adolescent children. Separate interviews were conducted with parents and adolescents from November to December 2021 using digital phone conferencing software. All interviews were recorded and transcribed. Thematic and constant comparative analysis techniques were used to identify relevant themes and subthemes. RESULTS: Twenty one healthcare workers (9 nurses, one nurse practitioner, one technologist, and 10 physicians) and their adolescents (N = 17) participated. Three overarching themes were identified to describe participants' perspectives about adolescent self-consent for COVID-19 vaccination: (1) Family values and practices around adolescent vaccination; (2) Differences in parent and adolescent support for vaccine self-consent laws; and (3) Parent and adolescent uncertainty on readiness for vaccine self-consent laws. Adolescents largely supported self-consent while parents supported the policy if they would be able to have a discussion with their adolescent prior to the decision. DISCUSSION: Parents and adolescents supported adolescent self-consent for COVID-19 vaccination, with the reservation that adolescents should discuss the decision alongside their parents to exercise their medical autonomy with supportive guidance. Greater adolescent involvement in making decisions and providing self-consent for healthcare, including vaccines, could prepare adolescents to have a greater sense of autonomy over their health and contribute to population health measures.

Effectiveness of mRNA-1273 vaccination against SARS-CoV-2 omicron subvariants BA.1, BA.2, BA.2.12.1, BA.4, and BA.5.

Studies have reported reduced natural SARS-CoV-2 infection- and vaccine-induced neutralization against omicron BA.4/BA.5 compared with earlier omicron subvariants. This test-negative case-control study evaluates mRNA-1273 vaccine effectiveness (VE) against infection and hospitalization with omicron subvariants. The study includes 30,809 SARS-CoV-2 positive and 92,427 SARS-CoV-2 negative individuals aged ≥18 years tested during 1/1/2022-6/30/2022. While 3-dose VE against BA.1 infection is high and wanes slowly, VE against BA.2, BA.2.12.1, BA.4, and BA.5 infection is initially moderate to high (61.0%-90.6% 14-30 days post third dose) and wanes rapidly. The 4-dose VE against infection with BA.2, BA.2.12.1, and BA.4 ranges between 64.3%-75.7%, and is low (30.8%) against BA.5 14-30 days post fourth dose, disappearing beyond 90 days for all subvariants. The 3-dose VE against hospitalization for BA.1, BA.2, and BA.4/BA.5 is 97.5%, 82.0%, and 72.4%, respectively; 4-dose VE against hospitalization for BA.4/BA.5 is 88.5%. Evaluation of the updated bivalent booster is warranted.

High-dose corticosteroids in patients hospitalized for COVID-19 pneumonia: an observational study of comparative effectiveness.

OBJECTIVES: To assess whether high- compared with low-dose corticosteroids started upon hospitalization reduce mortality in patients with severe COVID-19 pneumonia or in subgroups stratified by severity of respiratory impairment on admission. METHODS: We conducted a retrospective cohort study of patients with confirmed SARS-CoV-2 infection who required oxygen supplementation upon hospitalization between March 1 and December 31, 2020. In-hospital death was analyzed using logistic regression with inverse probability of treatment weighting of receiving low- or high-dose corticosteroid (dexamethasone 6-10 mg daily or >10-20 mg daily or other corticosteroid equivalents). RESULTS: We analyzed 13,366 patients who received low-dose and 948 who received high-dose corticosteroids, of whom 31.3% and 40.4% had severe respiratory impairment (>15 l/min of oxygen or mechanical ventilation) upon admission, respectively. There were no differences in the propensity score-adjusted odds of death (odds ratio 1.17, 95% CI 0.72-1.90) or infections (odds ratio 0.70, 95% CI 0.44-1.11) for patients who received high-dose compared with low-dose corticosteroids, beginning on the day of admission. No significant differences in subgroups stratified by severity of respiratory impairment were found. CONCLUSION: Initiating high-dose compared with low-dose corticosteroids among newly hospitalized patients with COVID-19 pneumonia did not improve survival. However, benefit of high-dose corticosteroids in specific subgroups cannot be excluded.

Durability of mRNA-1273 against COVID-19 in the time of Delta: Interim results from an observational cohort study.

BACKGROUND: We conducted a prospective cohort study at Kaiser Permanente Southern California to study the vaccine effectiveness (VE) of mRNA-1273 over time and during the emergence of the Delta variant. METHODS: The cohort for this planned interim analysis consisted of individuals aged ≥18 years receiving 2 doses of mRNA-1273 through June 2021, matched 1:1 to randomly selected unvaccinated individuals by age, sex, and race/ethnicity, with follow-up through September 2021. Outcomes were SARS-CoV-2 infection, and COVID-19 hospitalization and hospital death. Cox proportional hazards models were used to estimate adjusted hazard ratios (aHR) with 95% confidence intervals (CIs) comparing outcomes in the vaccinated and unvaccinated groups. Adjusted VE (%) was calculated as (1-aHR)x100. HRs and VEs were also estimated for SARS-CoV-2 infection by age, sex, race/ethnicity, and during the Delta period (June-September 2021). VE against SARS-CoV-2 infection and COVID-19 hospitalization was estimated at 0-<2, 2-<4, 4-<6, and 6-<8 months post-vaccination. RESULTS: 927,004 recipients of 2 doses of mRNA-1273 were matched to 927,004 unvaccinated individuals. VE (95% CI) was 82.8% (82.2-83.3%) against SARS-CoV-2 infection, 96.1% (95.5-96.6%) against COVID-19 hospitalization, and 97.2% (94.8-98.4%) against COVID-19 hospital death. VE against SARS-CoV-2 infection was similar by age, sex, and race/ethnicity, and was 86.5% (84.8-88.0%) during the Delta period. VE against SARS-CoV-2 infection decreased from 88.0% at 0-<2 months to 75.5% at 6-<8 months. CONCLUSIONS: These interim results provide continued evidence for protection of 2 doses of mRNA-1273 against SARS-CoV-2 infection over 8 months post-vaccination and during the Delta period, and against COVID-19 hospitalization and hospital death.

Changes in Testing and Diagnoses of Sexually Transmitted Infections and HIV During the COVID-19 Pandemic.

ABSTRACT: We evaluated changes in rates of testing and diagnoses of sexually transmitted infections during the 2017-2020 period at Kaiser Permanente Southern California. During the COVID-19 pandemic period, we observed profound reductions in testing and fewer diagnoses of chlamydia, gonorrhea, and HIV compared with prepandemic periods, but syphilis diagnoses rates increased by 32%.

"Still on the Fence": A Mixed Methods Investigation of COVID-19 Vaccine Confidence Among Health Care Providers.

BACKGROUND: There is evidence of disparities in COVID-19 vaccine acceptance among health care providers. The purpose of this study was to examine confidence receiving and recommending COVID-19 vaccines by health care provider type and race/ethnicity. METHODS: This mixed methods study involved a cross-sectional survey and qualitative, semi-structured interviews from March to May 2021 among a sample of physicians, advanced practice providers, nurses, and pharmacists. These workers were recruited through voluntary response sampling from an integrated health system in Southern California. The primary dependent variables were (a) confidence in vaccine safety, (b) confidence in vaccine effectiveness, and (c) intent to recommend the vaccine to others. The primary independent variables were health care provider type and race/ethnicity. FINDINGS: A total of 2,948 providers completed the survey. Nurses relative to physicians were 15% less likely to perceive the COVID-19 vaccine to be safe (risk ratio [RR] = 0.85; 95% confidence interval [CI] = 0.83-0.87); 27% less likely to perceive the vaccine to prevent COVID-19 (RR = 0.73; 95% CI = 0.69-0.76); and 11% less likely to recommend the vaccine to others (RR = 0.89; 95% CI = 0.87-0.91). Hispanic/Latinx providers were 10% less likely to perceive the vaccine to prevent COVID-19 (RR = 0.90; 95% CI = 0.83-0.98) relative to White providers. Qualitative themes included: No need for vaccine; distrusting vaccine research and roll-out; caretaking barriers; uncertainty and potential to change one's mind; framing vaccine decisions around personal beliefs. CONCLUSIONS & APPLICATION TO PRACTICE: Health care workplaces should consider interventions to increase COVID-19 vaccination among their workers, including education and mandatory vaccination policies.

Recombinant Adjuvanted Zoster Vaccine and Reduced Risk of Coronavirus Disease 2019 Diagnosis and Hospitalization in Older Adults.

BACKGROUND: Some vaccines elicit nonspecific immune responses that may protect against heterologous infections. We evaluated the association between recombinant adjuvanted zoster vaccine (RZV) and coronavirus disease 2019 (COVID-19) outcomes at Kaiser Permanente Southern California. METHODS: In a cohort design, adults aged ≥50 years who received ≥1 RZV dose before 1 March 2020 were matched 1:2 to unvaccinated individuals and followed until 31 December 2020. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for COVID-19 outcomes were estimated using Cox proportional hazards regression. In a test-negative design, cases had a positive severe acute respiratory syndrome coronavirus 2 test and controls had only negative tests, during 1 March-31 December 2020. Adjusted odds ratios (aORs) and 95% CIs for RZV receipt were estimated using logistic regression. RESULTS: In the cohort design, 149 244 RZV recipients were matched to 298 488 unvaccinated individuals. The aHRs for COVID-19 diagnosis and hospitalization were 0.84 (95% CI, .81-.87) and 0.68 (95% CI, .64-.74), respectively. In the test-negative design, 8.4% of 75 726 test-positive cases and 13.1% of 340 898 test-negative controls had received ≥1 RZV dose (aOR, 0.84 [95% CI, .81-.86]). CONCLUSIONS: RZV vaccination was associated with a 16% lower risk of COVID-19 diagnosis and 32% lower risk of hospitalization. Further study of vaccine-induced nonspecific immunity for potential attenuation of future pandemics is warranted.

Prevention of Coronavirus Disease 2019 Among Older Adults Receiving Pneumococcal Conjugate Vaccine Suggests Interactions Between Streptococcus pneumoniae and Severe Acute Respiratory Syndrome Coronavirus 2 in the Respiratory Tract.

BACKGROUND: While secondary pneumococcal pneumonia occurs less commonly after coronavirus disease 2019 (COVID-19) than after other viral infections, it remains unclear whether other interactions occur between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Streptococcus pneumoniae. METHODS: We probed potential interactions between these pathogens among adults aged ≥65 years by measuring associations of COVID-19 outcomes with pneumococcal vaccination (13-valent conjugate vaccine [PCV13] and 23-valent pneumococcal polysaccharide vaccine [PPSV23]). We estimated adjusted hazard ratios (aHRs) using Cox proportional hazards models with doubly robust inverse-propensity weighting. We assessed effect modification by antibiotic exposure to further test the biologic plausibility of a causal role for pneumococci. RESULTS: Among 531 033 adults, there were 3677 COVID-19 diagnoses, leading to 1075 hospitalizations and 334 fatalities, between 1 March and 22 July 2020. Estimated aHRs for COVID-19 diagnosis, hospitalization, and mortality associated with prior PCV13 receipt were 0.65 (95% confidence interval [CI], .59-.72), 0.68 (95% CI, .57-.83), and 0.68 (95% CI, .49-.95), respectively. Prior PPSV23 receipt was not associated with protection against the 3 outcomes. COVID-19 diagnosis was not associated with prior PCV13 within 90 days following antibiotic receipt, whereas aHR estimates were 0.65 (95% CI, .50-.84) and 0.62 (95% CI, .56-.70) during the risk periods 91-365 days and >365 days, respectively, following antibiotic receipt. CONCLUSIONS: Reduced risk of COVID-19 among PCV13 recipients, transiently attenuated by antibiotic exposure, suggests that pneumococci may interact with SARS-CoV-2.