Antibiotic resistance of urinary tract infection recurrences in a large U.S. integrated health care system.

BACKGROUND: Data on antibiotic resistance of uropathogens for UTI recurrences are lacking. METHODS: In a retrospective cohort of adults at Kaiser Permanente Southern California with culture-confirmed index uncomplicated UTI (uUTI) between 01/2016 and 12/2020, we examined the number and characteristics of subsequent culture-confirmed UTIs through 2021. RESULTS: We identified 148,994 individuals with a culture-confirmed index uUTI (88% female, 44% Hispanic, mean age 51 years [s.d. 19]), of whom 19% developed a subsequent culture-confirmed UTI after a median 300 days (IQR: 126-627). The proportion of UTI due to E. coli was highest for index uUTI (79%) and decreased to 73% for sixth UTI (UTI 6) (p-for trend <0.001), while the proportion due to Klebsiella spp increased from index UTI (7%) to UTI 6 (11%) (p-for-trend <0.001). Non-susceptibility to ≥1 and ≥3 antibiotic classes was observed in 57% and 13% of index uUTIs, respectively, and was higher for subsequent UTIs (65% and 20%, respectively, for UTI 6). Most commonly observed antibiotic non-susceptibility patterns included penicillins alone (12%), and penicillins, trimethoprim-sulfamethoxazole plus ≥1 additional antibiotic class (9%). CONCLUSIONS: Antibiotic non-susceptibility is common in UTIs and increases with subsequent UTIs. Continuous monitoring of UTI recurrences and susceptibility patterns are needed to guide treatment decisions.

Latent Tuberculosis Infection Testing Practices in a Large US Integrated Healthcare System.

BACKGROUND: Tuberculosis (TB) is a public health threat, with >80% of active TB in the United States occurring due to reactivation of latent TB infection (LTBI). We may be underscreening those with high risk for LTBI and overtesting those at lower risk. A better understanding of gaps in current LTBI testing practices in relation to LTBI test positivity is needed. METHODS: This study, conducted between 1 January 2008 and 31 December 2019 at Kaiser Permanente Southern California, included individuals aged ≥18 years without a history of active TB. We examined factors associated with LTBI testing and LTBI positivity. RESULTS: Among 3 816 884 adults (52% female, 37% White, 37% Hispanic, mean age 43.5 years [standard deviation, 16.1]), 706 367 (19%) were tested for LTBI, among whom 60 393 (9%) had ≥1 positive result. Among 1 211 971 individuals who met ≥1 screening criteria for LTBI, 210 025 (17%) were tested for LTBI. Factors associated with higher adjusted odds of testing positive included male sex (1.32; 95% confidence interval, 1.30-1.35), Asian/Pacific Islander (2.78, 2.68-2.88), current smoking (1.24, 1.20-1.28), diabetes (1.13, 1.09-1.16), hepatitis B (1.45, 1.34-1.57), hepatitis C (1.54, 1.44-1.66), and birth in a country with an elevated TB rate (3.40, 3.31-3.49). Despite being risk factors for testing positive for LTBI, none of these factors were associated with higher odds of LTBI testing. CONCLUSIONS: Current LTBI testing practices may be missing individuals at high risk of LTBI. Additional work is needed to refine and implement screening guidelines that appropriately target testing for those at highest risk for LTBI.

A Propensity Score Approach and a Partitioned Approach for the Self-Controlled Case Series Design to Evaluate Safety of a 2-dose Vaccine Series: Application to myocarditis/pericarditis following mRNA COVID-19 vaccination.

The assumption that serious adverse events (SAEs) do not affect subsequent exposure might not hold when evaluating 2-dose vaccine safety through a self-controlled case series (SCCS) design. To address this, we developed: 1) propensity score SCCS (PS-SCCS) using a propensity score model involving SAEs during the risk interval after dose 1 (${R}_1\Big)$, and 2) partitioned SCCS (P-SCCS) estimating relative incidence (RI) separately for doses 1 and 2. In simulations, both provided unbiased RIs. Conversely, standard SCCS overestimated RI after dose 2. We applied these approaches to assess myocarditis/pericarditis risks after 2-dose mRNA COVID-19 vaccination in 12-39-year-olds. For BNT162b2, PS-SCCS yielded RIs of 1.85 (95% CI, 0.75-4.59) and 11.05 (95% CI, 6.53-18.68) 14 days after doses 1 and 2 respectively; standard SCCS provided similar RI after dose 1 and RI of 12.92 (95% CI, 7.56-22.09) after dose 2. For mRNA-1273, standard SCCS showed RIs of 1.96 (95% CI, 0.56-6.91) after dose 1 and 7.87 (95% CI, 3.33-18.57) after dose 2. As no mRNA-1273 recipients with SAEs during ${R}_1$ received dose 2, P-SCCS was used, yielding similar RI after dose 1 and RI of 6.48 (95% CI, 2.83-14.83) after dose 2. mRNA vaccines were associated with elevated myocarditis/pericarditis risks following dose 2 in 12-39-year-olds.

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 and 2019. Case patients had diagnoses of lower respiratory tract infection (LRTI; including pneumonia or nonpneumonia LRTI diagnoses), with viral infections detected by multiplex polymerase chain reaction testing. Controls without LRTI diagnoses were matched to case patients by demographic and clinical attributes. We measured vaccine effectiveness (VE) for 13-valent (PCV13) against virus-associated LRTI by determining the adjusted odds ratio for PCV13 receipt, comparing case patients and controls. RESULTS: Primary analyses included 13 856 case patients with virus-associated LRTI and 227 887 matched controls. Receipt of PCV13 was associated with a VE of 24.9% (95% confidence interval, 18.4%-30.9%) against virus-associated pneumonia and 21.5% (10.9%-30.9%) against other (nonpneumonia) virus-associated LRTIs. We estimated VEs of 26.8% (95% confidence interval, 19.9%-33.1%) and 18.6% (9.3%-27.0%) 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. The impacts of pneumococcal conjugate vaccines may be mediated, in part, by effects on polymicrobial interactions between pneumococci and respiratory viruses.

Prevention of Neisseria gonorrhoeae With Meningococcal B Vaccine: A Matched Cohort Study in Southern California.

BACKGROUND: Neisseria gonorrhoeae is acquiring increasing resistance to available oral antibiotics, and current screening and treatment approaches have not decreased gonorrhea incidence. Although a gonorrhea-specific vaccine does not exist, N. gonorrhoeae shares much of its genome with Neisseria meningitidis, notably critical antigenic determinants including outer membrane vesicles (OMV). Prior observational studies have suggested that OMV-based meningococcal serogroup B vaccines confer protection against gonorrhea. METHODS: We conducted a matched cohort study from 2016 to 2020 to examine the association of OMV-containing recombinant meningococcal serogroup B vaccine (4CMenB) with gonorrhea infection among teens and young adults at Kaiser Permanente Southern California. Recipients of 4CMenB were matched in a ratio of 1:4 to recipients of non-OMV-containing polysaccharide-conjugate vaccine targeting serotypes A, C, W, and Y (MenACWY) who had not received 4CMenB and were followed for incident gonorrhea. We used Cox proportional hazards regression to compare gonorrhea rates among recipients of 4CMenB vs MenACWY, adjusting for potential confounders. We conducted the same analysis with chlamydia as a negative control outcome. RESULTS: The study included 6641 recipients of 4CMenB matched to 26 471 recipients of MenACWY. During follow-up, gonorrhea incidence rates per 1000 person-years (95% confidence intervals [CIs]) were 2.0 (1.3-2.8) for recipients of 4CMenB and 5.2 (4.6-5.8) for recipients of MenACWY. In adjusted analyses, gonorrhea rates were 46% lower among recipients of 4CMenB vs MenACWY (hazard ratio [HR], 0.54; 95% CI, .34-.86), but chlamydia rates were similar between vaccine groups (HR, 0.98; 95% CI, .82-1.17). CONCLUSIONS: These results suggest cross-protection of 4CMenB against gonorrhea, supporting the potential for vaccination strategies to prevent gonorrhea.

Effectiveness of Messenger RNA-1273 Vaccine Booster Against Coronavirus Disease 2019 in Immunocompetent Adults.

BACKGROUND: We conducted a prospective cohort study at Kaiser Permanente Southern California to evaluate the relative vaccine effectiveness (rVE) of a booster dose vs 2-dose primary series of messenger RNA (mRNA)-1273 in immunocompetent individuals. METHODS: Immunocompetent adults who received a booster dose of mRNA-1273 from October 2021 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 (aHRs) with 95% confidence intervals (CIs), comparing outcomes (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infection and coronavirus disease 2019 [COVID-19] hospitalization and hospital death) in the booster-dose and 2-dose groups. Adjusted rVE (%) was calculated as (1 - aHR) × 100. aHRs and rVE were also estimated by subgroup and 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 to <1 month of follow-up) to 30.5% (2 to <3 months). For COVID-19 hospitalization, rVE decreased from 91.2% (0 to <1 month) to 78.7% (2 to <3 months). CONCLUSIONS: Among immunocompetent adults, the mRNA-1273 booster conferred additional protection against SARS-CoV-2 infection and severe COVID-19 disease compared with the 2-dose mRNA-1273 primary series during periods of Delta and Omicron predominance.

Burden of Lower Respiratory Tract Infections Preventable by Adult Immunization With 15- and 20-Valent Pneumococcal Conjugate Vaccines in the United States.

BACKGROUND: Updated recommendations of the US Advisory Committee on Immunization Practices indicate that all adults aged ≥65 years and adults aged <65 years with comorbid conditions should receive 15- and 20-valent pneumococcal conjugate vaccines (PCV15/20). We aimed to assess the potential impact of these recommendations on the burden of lower respiratory tract infections (LRTIs) among adults. METHODS: We estimated the incidence of LRTI cases and associated hospital admissions among enrollees of Kaiser Permanente Southern California from 2016 through 2019. We used a counterfactual inference framework to estimate excess LRTI-associated risk of death up to 180 days after diagnosis. We used prior estimates of PCV13 effectiveness against LRTI to model potential direct effects of PCV15/20 by age group and risk status. RESULTS: Use of PCV15 and PCV20, respectively, could prevent 89.3 (95% confidence interval, 41.3-131.8) and 108.6 (50.4-159.1) medically attended LRTI cases; 21.9 (10.1-32.0) and 26.6 (12.4-38.7) hospitalized LRTI cases; and 7.1 (3.3-10.5) and 8.7 (4.0-12.7) excess LRTI-associated deaths, each per 10 000 person-years. Among at-risk adults aged <65 years, use of PCV15 and PCV20 could prevent 85.7 (39.6-131.5) and 102.7 (47.8-156.7) medically attended LRTI cases per 10 000 person-years; 5.1 (2.4-8.6) and 6.2 (2.8-10.2) LRTI hospitalizations per 10 000 person-years, and 0.9 (0.4-1.4) and 1.1 (0.5-1.7) excess LRTI-associated deaths per 10 000 person-years. CONCLUSIONS: Our findings suggest recent recommendations, including PCV15/20 within adult pneumococcal vaccine series, may substantially reduce LRTI burden.

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.

Understanding Barriers and Facilitators of Pre-exposure Prophylaxis (PrEP) Among Transgender and Gender Diverse Adults in an Integrated Health Care System.

Transgender and gender diverse individuals face health disparities such as higher HIV prevalence, but limited studies have found low PrEP uptake among these populations. To understand both patient and provider perspectives regarding PrEP care for transgender and gender diverse individuals, we conducted a mixed-methods study at Kaiser Permanente Southern California from September 2020 to October 2021. Transgender and gender diverse adults (N = 396) participated in a web-based survey, and qualitative interviews were subsequently conducted with a subset of survey respondents (N = 32) and healthcare providers (N = 8). Among survey respondents, > 75% were familiar with PrEP, and > 40% reported at least one HIV risk factor, but < 5% had taken PrEP. Interview themes included increasing providers' inclusivity in primary care for transgender and gender diverse patients, and reducing logistical barriers and costs associated with PrEP-related visits. To improve PrEP uptake among transgender and gender diverse individuals, barriers across patient, provider, and health system levels must be addressed.

Patient-Reported Barriers to Treatment Initiation and Completion for Latent Tuberculosis Infection Among Patients Within a Large Integrated Health Care System in Southern California.

OBJECTIVE: More than 80% of active tuberculosis in the United States is due to reactivation of latent tuberculosis infection (LTBI), which can be prevented via screening and treatment. Treatment initiation and completion rates are low for patients with LTBI in the United States, and the barriers to successful treatment are poorly understood. DESIGN: We conducted semistructured qualitative interviews with 38 patients who were prescribed LTBI treatment (9 months isoniazid, 6 months rifampin, or 3 months rifamycin-isoniazid short-course combinations). We used purposeful sampling employing a maximum variation approach to obtain diverse perspectives of patients who did not initiate treatment, who did not complete treatment, and who completed treatment (n = 14, n = 16, and n = 8, respectively). Patients were asked about LTBI knowledge, experience regarding treatment, interactions with providers, and barriers they faced. Using a team coding model (2 coders/analysts), we developed deductively derived (a priori) codes based on our central research questions and inductively derived codes that emerged directly from the data. Analysis of our coding categories and relationships generated a hierarchy of key themes and subthemes. SETTING: Kaiser Permanente Southern California. PARTICIPANTS: Individuals 18 years or older who received a diagnosis of LTBI and prescribed treatment. MAIN OUTCOME MEASURES: LTBI knowledge, attitudes toward LTBI, attitudes toward LTBI treatment, attitudes toward providers, and explanation of barriers. RESULTS: Most patients reported having limited knowledge of LTBI. In addition to the duration of treatment, barriers to initiation and completion included perceived lack of support, uncomfortable side effects, and pervasive minimization of the positive impact of treatment on their health. Many patients felt there was little incentive to overcome barriers. CONCLUSIONS: Overall, patient experience with LTBI treatment initiation and completion could be improved with patient-centered treatment and more frequent follow-ups.

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.

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.

Effectiveness of 13-Valent Pneumococcal Conjugate Vaccine Against Medically Attended Lower Respiratory Tract Infection and Pneumonia Among Older Adults.

BACKGROUND: Among older adults, 13-valent pneumococcal conjugate vaccine (PCV13) has been found efficacious against nonbacteremic pneumonia associated with vaccine-serotype pneumococci. However, the burden of lower respiratory tract infection (LRTI) and pneumonia preventable by direct immunization of older adults continues to be debated. METHODS: We analyzed data from an open cohort of adults aged ≥65 years enrolled in Kaiser Permanente Southern California health plans from 2016 to 2019 who received PCV13 concordant with US Advisory Committee on Immunization Practices guidelines. We estimated PCV13 vaccine effectiveness (VE) via the adjusted hazard ratio for first LRTI and pneumonia episodes during each respiratory season, comparing PCV13-exposed and PCV13-unexposed time at risk for each participant using a self-matched inference framework. Analyses used Cox proportional hazards models, stratified by individual. RESULTS: Among 42 700 adults who met inclusion criteria, VE was 9.5% (95% confidence interval [CI], 2.2% to 16.3%) against all-cause medically attended LRTI and 8.8% (95% CI, -.2% to 17.0%) against all-cause medically attended pneumonia. In contrast, we did not identify evidence of protection against LRTI and pneumonia following receipt of the 23-valent pneumococcal polysaccharide vaccine. PCV13 prevented 0.7 (95% CI, .2 to 1.4) and 0.5 (95% CI, .0 to 1.0) cases of LRTI and pneumonia, respectively, per 100 vaccinated persons annually; over 5 years, 1 case of LRTI and 1 case of pneumonia were prevented for every 27 and 42 individuals vaccinated, respectively. CONCLUSIONS: PCV13 vaccination among older adults substantially reduced incidence of medically attended respiratory illness. Direct immunization of older adults is an effective strategy to combat residual disease burden associated with PCV13-type pneumococci.

Influenza vaccination and mortality among adults with heart failure in an integrated healthcare delivery system, 2009-2018.

BACKGROUND: Influenza infection can result in decompensation or exacerbation of heart failure (HF) symptoms, hospitalization, and death. OBJECTIVE: To examine the association of influenza vaccination with mortality and hospitalization during influenza and non-influenza seasons between 2009 and 2018. DESIGN, SETTING, AND PARTICIPANTS: In this prospective, observational cohort study, we included Kaiser Permanente Southern California members with a HF diagnosis prior to September 1 each year from 2009 to 2017. EXPOSURE: The first influenza vaccination in each season (September 1 to May 31) was recorded. Vaccinated/unvaccinated patients were matched 1:1 on age, sex, and ejection fraction at the vaccination date (n-total = 74,870). MAIN OUTCOMES: Patients were followed through the end of each influenza season for all-cause mortality. Secondary outcomes included cardiovascular mortality and all-cause hospitalization. In a sensitivity analysis, we examined mortality in the non-influenza season. RESULTS: Influenza vaccinated vs unvaccinated patients had more comorbidities and higher healthcare utilization. After multivariable adjustment for utilization, sociodemographics, comorbidities, and medications, influenza vaccinated vs unvaccinated patients had a lower risk of all-cause mortality and cardiovascular mortality during the influenza season (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.63, 0.70 and HR 0.68, 95% CI 0.63, 0.74, respectively) but a higher risk of all-cause hospitalization (HR 1.27, 95% CI 1.21, 1.31). There was no association between influenza vaccination and all-cause or cardiovascular mortality during the non-influenza season (HR 0.99, 95% CI 0.89, 1.09 and HR 1.00, 95% CI 0.84, 1.21, respectively). CONCLUSIONS: Influenza vaccination in HF patients was associated with a lower risk of mortality during the influenza season. Our findings provide support for recommendations of universal influenza vaccination in patients with HF.

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%.

Association Between 2-Dose vs 3-Dose Hepatitis B Vaccine and Acute Myocardial Infarction.

Importance: The 2-dose hepatitis B vaccine with a cytosine phosphoguanine adjuvant (HepB-CpG vaccine; Heplisav-B) generated higher seroprotection in prelicensure trials than did a 3-dose hepatitis B vaccine with an aluminum hydroxide adjuvant (HepB-alum vaccine; Engerix-B). However, in 1 trial, a higher number of acute myocardial infarction (MI) events were observed among those who received the HepB-CpG vaccine than among those who received the HepB-alum vaccine, an outcome requiring further study. Objective: To compare the rate of acute MI between recipients of HepB-CpG vaccine and HepB-alum vaccine. Design, Setting, and Participants: This prospective cohort noninferiority study was conducted at Kaiser Permanente Southern California (KPSC), an integrated health care system with 15 medical centers and approximately 4.7 million members. The study included 69 625 adults not undergoing dialysis who received at least 1 dose of a hepatitis B vaccine in either family medicine or internal medicine departments at KPSC from August 7, 2018, to October 31, 2019 (November 30, 2020, final follow-up). Exposures: Receipt of HepB-CpG vaccine vs HepB-alum vaccine. The first dose during the study period was the index dose. Main Outcomes and Measures: Individuals were followed up for 13 months after the index dose for occurrence of type 1 acute MI. Potential events were identified using diagnosis codes and adjudicated by cardiologists. The adjusted hazard ratio (HR) of acute MI was estimated comparing recipients of HepB-CpG vaccine with recipients of HepB-alum vaccine, with inverse probability of treatment weighting (IPTW) to adjust for demographic and clinical characteristics. The upper limit of the 1-sided 97.5% CI was compared with a noninferiority margin of 2. Results: Of the 31 183 recipients of HepB-CpG vaccine (median age, 49 years; IQR, 38-56 years), 51.2% (n = 15 965) were men, and 52.7% (n = 16 423) were Hispanic. Of the 38 442 recipients of HepB-alum (median age, 49 years; IQR, 39-56 years), 50.8% (19 533) were men, and 47.1% (n = 18 125) were Hispanic. Characteristics were well-balanced between vaccine groups after IPTW. Fifty-two type 1 acute MI events were confirmed among recipients of HepB-CpG vaccine for a rate of 1.67 per 1000-person-years, and 71 type 1 acute MI events were confirmed among recipients of HepB-alum vaccine for a rate of 1.86 per 1000 person-years (absolute rate difference, -0.19 [95% CI, -0.82 to 0.44]; adjusted HR, 0.92 [1-sided 97.5% CI, ∞ to 1.32], which was below the noninferiority margin; P < .001 for noninferiority). Conclusions and Relevance: In this cohort study, receipt of HepB-CpG vaccine compared with HepB-alum vaccine did not meet the statistical criterion for increased risk of acute myocardial infarction.

Parent intentions to vaccinate children with autism spectrum disorder against COVID-19.

PURPOSE: The purpose of this study was to investigate associations between parent vaccine confidence and intention to have their child with autism vaccinated against COVID-19. DESIGN AND METHODS: A cross-sectional, web-based survey was conducted from May to July 2021 with parents of children with autism spectrum disorder (N = 322) who were members of an integrated healthcare system in Southern California. RESULTS: Approximately 35% of parents intended to vaccinate their child against COVID-19. In adjusted models, positive vaccine beliefs-but not belief in vaccine harm, healthcare provider trust, or parent vaccination status-were associated with intention to vaccinate. CONCLUSIONS: Though parents usually trust recommendations from pediatric healthcare providers to make decisions about their child's health, these findings suggest that relying on trusted relationships alone may not be sufficient when discussing COVID-19 vaccines and that additional education to bolster vaccine confidence may be needed. PRACTICE IMPLICATIONS: Pediatric healthcare providers should reinforce the benefits of vaccines for parents who are undecided about COVID-19 vaccines for their children and provide education and evidence-based recommendations to parents who hold erroneous vaccine beliefs about risks, benefits, and current evidence, especially those related to autism.

Inference of Naturally Acquired Immunity Using a Self-matched Negative-Control Design.

Host adaptive immune responses may protect against infection or disease when a pathogen is repeatedly encountered. The hazard ratio of infection or disease, given previous infection, is typically sought to estimate the strength of protective immunity. However, variation in individual exposure or susceptibility to infection may introduce frailty bias, whereby a tendency for infections to recur among individuals with greater risk confounds the causal association between previous infection and susceptibility. We introduce a self-matched "case-only" inference method to control for unmeasured individual heterogeneity, making use of negative-control endpoints not attributable to the pathogen of interest. To control for confounding, this method compares event times for endpoints due to the pathogen of interest and negative-control endpoints during counterfactual risk periods, defined according to individuals' infection history. We derive a standard Mantel-Haenszel (matched) odds ratio conveying the effect of prior infection on time to recurrence. We compare performance of this approach to several proportional hazards modeling frameworks and estimate statistical power of the proposed strategy under various conditions. In an example application, we use the proposed method to reestimate naturally acquired protection against rotavirus gastroenteritis using data from previously published cohort studies. This self-matched negative-control design may present a flexible alternative to existing approaches for analyzing naturally acquired immunity, as well as other exposures affecting the distribution of recurrent event times.

Distribution of SARS-CoV-2 Variants in a Large Integrated Health Care System - California, March-July 2021.

Data from observational studies demonstrate that variants of SARS-CoV-2, the virus that causes COVID-19, have evolved rapidly across many countries (1,2). The SARS-CoV-2 B.1.617.2 (Delta) variant of concern is more transmissible than previously identified variants,* and as of September 2021, is the predominant variant in the United States.† Studies characterizing the distribution and severity of illness caused by SARS-CoV-2 variants, particularly the Delta variant, are limited in the United States (3), and are subject to limitations related to study setting, specimen collection, study population, or study period (4-7). This study used whole genome sequencing (WGS) data on SARS-CoV-2-positive specimens collected across Kaiser Permanente Southern California (KPSC), a large integrated health care system, to describe the distribution and risk of hospitalization associated with SARS-CoV-2 variants during March 4-July 21, 2021, by patient vaccination status. Among 13,039 SARS-CoV-2-positive specimens identified from KPSC patients during this period, 6,798 (52%) were sequenced and included in this report. Of these, 5,994 (88%) were collected from unvaccinated persons, 648 (10%) from fully vaccinated persons, and 156 (2%) from partially vaccinated persons. Among all sequenced specimens, the weekly percentage of B.1.1.7 (Alpha) variant infections increased from 20% to 67% during March 4-May 19, 2021. During April 15-July 21, 2021, the weekly percentage of Delta variant infections increased from 0% to 95%. During March 4-July 21, 2021, the weekly percentage of variants was similar among fully vaccinated and unvaccinated persons, but the Delta variant was more commonly identified among vaccinated persons then unvaccinated persons overall, relative to other variants. The Delta variant was more prevalent among younger persons, with the highest percentage (55%) identified among persons aged 18-44 years. Infections attributed to the Delta variant were also more commonly identified among non-Hispanic Black persons, relative to other variants. These findings reinforce the importance of continued monitoring of SARS-CoV-2 variants and implementing multiple COVID-19 prevention strategies, particularly during the current period in which Delta is the predominant variant circulating in the United States.

Hepatitis B vaccine and risk of acute myocardial infarction among individuals with diabetes mellitus.

PURPOSE: A pre-licensure clinical trial of a two-dose cytosine phosphoguanine adjuvanted hepatitis B vaccine (HEPLISAV-B® [Dynavax, USA]; HepB-CpG vaccine) found an unanticipated numerical imbalance in acute myocardial infarction (AMI) compared to recipients of a three-dose aluminum adjuvanted hepatitis B vaccine (ENGERIX-B® [GlaxoSmithKline, Belgium]; HepB-alum vaccine). A post-licensure study was required to compare AMI rates among recipients of HepB-CpG vaccine and HepB-alum vaccine. Individuals with diabetes mellitus (DM), who are at higher risk of AMI, comprise more than half of the post-licensure study cohort. To inform the ongoing post-licensure study, we examined the association between AMI and receipt of HepB-alum vaccine in individuals with DM. METHODS: We conducted a case-control study nested in a cohort of individuals with DM ages ≥40 years at Kaiser Permanente Southern California using electronic health records. AMI cases from 2012 to 2017 were identified by principal discharge diagnosis and matched 1:1 with randomly selected controls. The adjusted odds ratio (aOR) for receipt of ≥1 HepB-alum vaccine dose was compared for AMI cases and controls using conditional logistic regression. We subsequently performed the same matched case-control analysis stratified by year. RESULTS: Of 8138 matched case-control pairs, 17.4% of cases and 15.0% of controls received HepB-alum vaccine. The aOR of HepB-alum vaccination comparing cases and controls was 0.97 (95% confidence interval 0.87-1.08). Similarly, there was no significant association between HepB-alum vaccine and AMI in any of the study years. CONCLUSIONS: HepB-alum vaccination was not associated with AMI in individuals with DM. This finding will provide contextual insight for the ongoing post-licensure study of HepB-CpG vaccine.