Effectiveness and durability of mRNA-1273 BA.4/BA.5 bivalent vaccine (mRNA-1273.222) against SARS-CoV-2 BA.4/BA.5 and XBB sublineages

Emerging SARS-CoV-2 sublineages continue to cause serious COVID-19 disease, but most individuals have not received any COVID-19 vaccine for >1 year. Assessment of long-term effectiveness of bivalent COVID-19 vaccines against circulating sublineages is important to inform the potential need for vaccination with updated vaccines. In this test-negative study at Kaiser Permanente Southern California, sequencing-confirmed BA.4/BA.5- or XBB-related SARS-CoV-2-positive cases (September 1, 2022 to June 30, 2023), were matched 1:3 to SARS-CoV-2-negative controls. We assessed mRNA-1273 bivalent relative (rVE) and absolute vaccine effectiveness (VE) compared to ≥2 or 0 doses of original monovalent vaccine, respectively. The rVE analysis included 20,966 cases and 62,898 controls. rVE (95%CI) against BA.4/BA.5 at 14-60 days and 121-180 days was 52.7% (46.9-57.8%) and 35.5% (-2.8-59.5%) for infection, and 59.3% (49.7-67.0%) and 33.2% (-28.2-68.0%) for Emergency Department/Urgent Care (ED/UC) encounters. For BA.4/BA.5-related hospitalizations, rVE was 71.3% (44.9-85.1%) and 52.0% (-1.2-77.3%) at 14-60 days and 61-120 days, respectively. rVE against XBB at 14-60 days and 121-180 days was 48.8% (33.4-60.7%) and -3.9% (-18.1-11.3%) for infection, 70.7% (52.4-82.0%) and 15.7% (-6.0-33.2%) for ED/UC encounters, and 87.9% (43.8-97.4%) and 57.1% (17.0-77.8%) for hospitalization. VE and subgroup analyses (age, immunocompromised status, previous SARS-CoV-2 infection) results were similar to rVE analyses. rVE of mRNA-1273 bivalent vaccine against BA.4/BA.5 and XBB infections, ED/UC encounters, and hospitalizations waned over time. Periodic revaccination with vaccines targeting emerging variants may be important in reducing COVID-19 morbidity and mortality.

Real-world effectiveness of recombinant zoster vaccine in self-identified Chinese individuals aged ≥50 years in the United States

We evaluated the vaccine effectiveness (VE) of two doses of recombinant zoster vaccine (RZV) against herpes zoster (HZ) and postherpetic neuralgia (PHN) in Chinese adults at Kaiser Permanente Southern California (KPSC). Chinese KPSC members were identified based on self-reported ethnicity or self-reported preferred spoken/written language. Those aged ≥50 years who received two doses of RZV 4 weeks to ≤ 6 months apart were matched 1:4 to RZV unvaccinated Chinese members and followed through June 2022; second doses were accrued 6/1/2018-12/31/2020. We estimated incidence and adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) comparing outcomes (HZ and PHN). Adjusted VE (%) was calculated as (1-aHR)×100. 3978 RZV vaccinated Chinese members were matched to 15,912 RZV unvaccinated Chinese members. The incidence per 1000 person-years (95% CI) of HZ in the vaccinated group was 1.5 (0.9-2.5) and 10.9 (9.8-12.1) in the unvaccinated group; aHR (95% CI) was 0.12 (0.07-0.21). Adjusted VE (95% CI) was 87.6% (78.9-92.7) against HZ. We identified 0 PHN cases in the vaccinated group and 19 in the unvaccinated group. Among Chinese adults aged ≥50 years, two doses of RZV provided substantial protection against HZ and PHN supporting the real-world effectiveness of the vaccine in this population.

Influenza vaccination coverage among persons ages six months and older in the Vaccine Safety Datalink in the 2017-18 through 2022-23 influenza seasons

BACKGROUND

In the United States, annual vaccination against seasonal influenza is recommended for all people ages ≥ 6 months. Vaccination coverage assessments can identify populations less protected from influenza morbidity and mortality and help to tailor vaccination efforts. Within the Vaccine Safety Datalink population ages ≥ 6 months, we report influenza vaccination coverage for the 2017-18 through 2022-23 seasons.

METHODS

Across eight health systems, we identified influenza vaccines administered from August 1 through March 31 for each season using electronic health records linked to immunization registries. Crude vaccination coverage was described for each season, overall and by self-reported sex; age group; self-reported race and ethnicity; and number of separate categories of diagnoses associated with increased risk of severe illness and complications from influenza (hereafter referred to as high-risk conditions). High-risk conditions were assessed using ICD-10-CM diagnosis codes assigned in the year preceding each influenza season.

RESULTS

Among individual cohorts of more than 12 million individuals each season, overall influenza vaccination coverage increased from 41.9 % in the 2017-18 season to a peak of 46.2 % in 2019-20, prior to declaration of the COVID-19 pandemic. Coverage declined over the next three seasons, coincident with widespread SARS-CoV-2 circulation, to a low of 40.3 % in the 2022-23 season. In each of the six seasons, coverage was lowest among males, 18-49-year-olds, non-Hispanic Black people, and those with no high-risk conditions. While decreases in coverage were present in all age groups, the declines were most substantial among children: 2022-23 season coverage for children ages six months through 8 years and 9-17 years was 24.5 % and 22.4 % (14 and 10 absolute percentage points), respectively, less than peak coverage achieved in the 2019-20 season.

CONCLUSIONS

Crude influenza vaccination coverage increased from 2017 to 18 through 2019-20, then decreased to the lowest level in the 2022-23 season. In this insured population, we identified persistent disparities in influenza vaccination coverage by sex, age, and race and ethnicity. The overall low coverage, disparities in coverage, and recent decreases in coverage are significant public health concerns.

mRNA-1273 bivalent (original and Omicron) COVID-19 vaccine effectiveness against COVID-19 outcomes in the United States

The bivalent (original and Omicron BA.4/BA.5) mRNA-1273 COVID-19 vaccine was authorized to offer broader protection against COVID-19. We conducted a matched cohort study to evaluate the effectiveness of the bivalent vaccine in preventing hospitalization for COVID-19 (primary outcome) and medically attended SARS-CoV-2 infection and hospital death (secondary outcomes). Compared to individuals who did not receive bivalent mRNA vaccination but received ≥2 doses of any monovalent mRNA vaccine, the relative vaccine effectiveness (rVE) against hospitalization for COVID-19 was 70.3% (95% confidence interval, 64.0%-75.4%). rVE was consistent across subgroups and not modified by time since last monovalent dose or number of monovalent doses received. Protection was durable ≥3 months after the bivalent booster. rVE against SARS-CoV-2 infection requiring emergency department/urgent care and against COVID-19 hospital death was 55.0% (50.8%-58.8%) and 82.7% (63.7%-91.7%), respectively. The mRNA-1273 bivalent booster provides additional protection against hospitalization for COVID-19, medically attended SARS-CoV-2 infection, and COVID-19 hospital death.

Timely Prenatal and Infant Pertussis Vaccine Uptake in an Integrated Health System

BACKGROUND

Hispanic infants bear the burden of pertussis infection. We examined pertussis protection from vaccination in infants with US-born and foreign-born Hispanic mothers.

METHODS

Retrospective cohort study of infants up to 1 year of age. Secondary data of mothers with continuous membership since the 27th week of pregnancy with infants born 1/1/2012-12/31/2017 in an integrated health care delivery organization, which broadly represent the Southern California population.

RESULTS

Foreign-born Hispanic mothers had higher prenatal tetanus, diphtheria, acellular pertussis (Tdap) uptake compared to US-born white mothers [adjusted risk ratio (aRR): 1.04, 95% confidence interval (CI): 1.03, 1.05]. Infants with mothers on Medicaid insurance disproportionately did not enroll in the health plan by the time they were eligible for their first dose of the DTaP vaccine (68.4%). Once initiating the infant vaccine series, foreign-born Hispanic mothers more likely adhered than US-born white mothers (aRR: 1.05, CI: 1.02, 1.08).

DISCUSSION

In an integrated health system, disparities in vaccine uptake can be minimized. Infants who are born to mothers with Medicaid insurance and are not enrolled in the health plan after birth may be under-protected from pertussis.

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.

Tdap vaccination during pregnancy and risk of chorioamnionitis and related infant outcomes

INTRODUCTION

An increased risk of chorioamnionitis in people receiving tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine during pregnancy has been reported. The importance of this association is unclear as additional study has not demonstrated increased adverse infant outcomes associated with Tdap vaccination in pregnancy.

METHODS

We conducted a retrospective observational cohort study of pregnant people ages 15-49 years with singleton pregnancies ending in live birth who were members of 8 Vaccine Safety Datalink (VSD) sites during October 2016-September 2018. We used a time-dependent covariate Cox model with stabilized inverse probability weights applied to evaluate associations between Tdap vaccination during pregnancy and chorioamnionitis and preterm birth outcomes. We used Poisson regression with robust variance with stabilized inverse probability weights applied to evaluate the association of Tdap vaccination with adverse infant outcomes. We performed medical record reviews on a random sample of patients with ICD-10-CM-diagnosed chorioamnionitis to determine positive predictive values (PPV) of coded chorioamnionitisfor "probable clinical chorioamnionitis," "possible clinical chorioamnionitis," or "histologic chorioamnionitis."

RESULTS

We included 118,211 pregnant people; 103,258 (87%) received Tdap vaccine during pregnancy; 8098 (7%) were diagnosed with chorioamnionitis. The adjusted hazard ratio for chorioamnionitis in the Tdap vaccine-exposed group compared to unexposed was 0.96 (95% CI 0.90-1.03). There was no association between Tdap vaccine and preterm birth or adverse infant outcomes associated with chorioamnionitis. Chart reviews were performed for 528 pregnant people with chorioamnionitis. The PPV for clinical (probable or possible clinical chorioamnionitis) was 48% and 59% for histologic chorioamnionitis. The PPV for the combined outcome of clinical or histologic chorioamnionitis was 81%.

CONCLUSIONS AND RELEVANCE

Tdap vaccine exposure during pregnancy was not associated with chorioamnionitis, preterm birth, or adverse infant outcomes. ICD-10 codes for chorioamnionitis lack specificity for clinical chorioamnionitis and should be a recognized limitation when interpreting results.

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.

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.

Impact of a Statewide Livestock Antibiotic Use Policy on Resistance in Human Urine Escherichia coli Isolates: A Synthetic Control Analysis

BACKGROUND

On 1 January 2018, California implemented Senate Bill 27 (SB27), banning, for the first time in the United States, routine preventive use of antibiotics in food-animal production and any antibiotic use without a veterinarian's prescription.

OBJECTIVES

Our objective was to assess whether SB27 was associated with decreased antimicrobial resistance among E. coli isolated from human urine.

METHODS

We used U.S. nationwide monthly state-level data from BD Insights Research Database (Becton, Dickinson, and Co.) spanning 1 January 2013 to 30 June 2021 on antibiotic-resistance patterns of 30-d nonduplicate E. coli isolated from urine. Tested antibiotic classes included aminoglycosides, extended-spectrum cephalosporins (ESC), fluoroquinolones, and tetracyclines. Counts of tested and not-susceptible (resistant and intermediate, hereafter resistant) urine isolates were available by sex, age group (<65, 65+ year), month, and state. We applied a synthetic control approach to estimate the causal effect of SB27 on resistance patterns. Our approach created a synthetic California based on a composite of other states without the policy change and contrasted its counterfactual postpolicy trends with the observed postpolicy trends in California.

FINDINGS

We included 7.1 million E. coli urine isolates, 90% among women, across 33 states. From 2013 to 2017, the median (interquartile range) resistance percentages in California were 11.9% (7.4, 17.6), 13.8% (5.8, 20.0), 24.6% (9.6, 36.4), 7.9% (2.1, 13.1), for aminoglycosides, ESC, fluoroquinolones, and tetracyclines, respectively. SB27 was associated with a 7.1% reduction in ESC resistance (p-value for joint null: <0.01), but no change in resistance to aminoglycosides, fluoroquinolones, or tetracyclines.

DISCUSSION

Further research is needed to determine the role of SB27 in the observed reduction in ESC resistance E. coli in human populations, particularly as additional states implement similar legislation. https://doi.org/10.1289/EHP11221.

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.

Analysis of mRNA COVID-19 Vaccine Uptake Among Immunocompromised Individuals in a Large US Health System

Importance

Immunocompromised individuals are at increased risk for severe outcomes due to SARS-CoV-2 infection. Given the varying and complex nature of COVID-19 vaccination recommendations, it is important to understand COVID-19 vaccine uptake in this vulnerable population.

Objective

To assess mRNA COVID-19 vaccine uptake and factors associated with uptake among immunocompromised individuals from December 14, 2020, through August 6, 2022.

Design, Setting, and Participants

This cohort study was conducted with patients of Kaiser Permanente Southern California (KPSC), an integrated health care system in the US. The study included patients aged 18 years or older who were immunocompromised (individuals with an immunocompromising condition or patients who received immunosuppressive medications in the year prior to December 14, 2020) and still met criteria for being immunocompromised 1 year later.

Exposures

Age, sex, self-identified race and ethnicity, prior positive COVID-19 test result, immunocompromising condition, immunomodulating medication, comorbidities, health care utilization, and neighborhood median income.

Main Outcomes and Measures

Outcomes were the number of doses of mRNA COVID-19 vaccine received and the factors associated with receipt of at least 4 doses, estimated by hazard ratios (HRs) and 95% Wald CIs via Cox proportional hazards regression. Statistical analyses were conducted between August 9 and 23, 2022.

Results

Overall, 42 697 immunocompromised individuals met the study eligibility criteria. Among these, 18 789 (44.0%) were aged 65 years or older; 20 061 (47.0%) were women and 22 635 (53.0%) were men. With regard to race and ethnicity, 4295 participants (10.1%) identified as Asian or Pacific Islander, 5174 (12.1%) as Black, 14 289 (33.5%) as Hispanic, and 17 902 (41.9%) as White. As of the end of the study period and after accounting for participant censoring due to death or disenrollment from the KPSC health plan, 78.0% of immunocompromised individuals had received a third dose of mRNA COVID-19 vaccine. Only 41.0% had received a fourth dose, which corresponds to a primary series and a monovalent booster dose for immunocompromised individuals. Uptake of a fifth dose was only 0.9% following the US Centers for Disease Control and Prevention (CDC) recommendation to receive a second monovalent booster (ie, fifth dose). Adults aged 65 years or older (HR, 3.95 [95% CI, 3.70-4.22]) were more likely to receive at least 4 doses compared with those aged 18 to 44 years or 45 to 64 years (2.52 [2.36-2.69]). Hispanic and non-Hispanic Black adults (HR, 0.77 [95% CI, 0.74-0.80] and 0.82 [0.78-0.87], respectively, compared with non-Hispanic White adults), individuals with prior documented SARS-CoV-2 infection (0.71 [0.62-0.81] compared with those without), and individuals receiving high-dose corticosteroids (0.88 [0.81-0.95] compared with those who were not) were less likely to receive at least 4 doses.

Conclusions and Relevance

These findings suggest that adherence to CDC mRNA monovalent COVID-19 booster dose recommendations among immunocompromised individuals was low. Given the increased risk for severe COVID-19 in this vulnerable population and the well-established additional protection afforded by booster doses, targeted and tailored efforts to ensure that immunocompromised individuals remain up to date with COVID-19 booster dose recommendations are warranted.

Risk of herpes zoster following mRNA COVID-19 vaccine administration

BACKGROUND

Adverse events following mRNA COVID-19 vaccines, including herpes zoster (HZ), have been reported. We conducted a cohort study to evaluate the association between mRNA COVID-19 vaccination and subsequent HZ at Kaiser Permanente Southern California (KPSC).

RESEARCH DESIGN AND METHODS

The vaccinated cohort consisted of KPSC members who received their first dose of mRNA COVID-19 vaccine (mRNA-1273 and BNT162b2) during 12/2020-05/2021 and were matched to unvaccinated individuals on age and sex. Incident HZ cases occurring within 90 days of follow-up were identified by diagnosis codes and antiviral medications. Cox proportional hazards models estimated adjusted hazard ratios (aHR), comparing HZ incidence between the vaccinated and unvaccinated cohorts.

RESULTS

Cohort included 1,052,362 mRNA-1273 recipients, 1,055,461 BNT162b2 recipients, and 1,020,334 comparators. Compared to unvaccinated individuals, aHR for HZ up to 90 days after the second dose of mRNA-1273 and BNT162b2 was 1.14 (1.05-1.24) and 1.12 (1.03-1.22), respectively. In those aged ≥50 years not vaccinated with zoster vaccine, aHR was also increased after the second dose of mRNA-1273 (1.18 [1.06-1.33]) and BNT162b2 (1.15 [1.02-1.29]) vaccine vs. unvaccinated individuals.

CONCLUSIONS

Our findings suggest a potential increased risk of HZ after a second dose of mRNA vaccines, potentially driven by the increased risk in individuals aged ≥50 years without history of zoster vaccination.

784. Real-world effectiveness of the mRNA-12733-dose primary series against COVID-19 in an immunocompromised population Interim results from a prospective observational cohort study

Background

While a 3-dose mRNA-1273 primary series is recommended for moderately or severely immunocompromised (IC) individuals in the U.S., some IC individuals do not complete the 3-dose series. We conducted a matched cohort study to evaluate the relative vaccine effectiveness (rVE) of the 3-dose mRNA-1273 primary series vs. 2 doses of mRNA-1273 in preventing SARS-CoV-2 infection and severe COVID-19 disease in IC individuals.

Methods

IC individuals aged ≥18 years with ≥12 months of Kaiser Permanente Southern California membership who received 3 doses of mRNA-1273 ≥24 days apart were 1:1 matched with randomly selected IC 2-dose recipients on age, sex, race/ethnicity, and 2^nd dose date. Third doses were accrued from 08/12/2021 to 12/31/2021, with follow-up through 1/31/2022, spanning the delta and omicron periods. Outcomes were SARS-CoV-2 infection (positive molecular test or diagnosis code), COVID-19 hospitalization, and COVID-19 hospital death. Adjusted hazard ratios (aHR) with confidence intervals (CI) were estimated by Cox proportional hazards models. Adjusted rVE (%) was calculated as (1-aHR) x 100.

Results

Our study included 21,942 3-dose and 21,942 2-dose mRNA-1273 IC recipients. Adjusted rVE of 3 doses compared to 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 (Table 1). Adjusted rVE against SARS-CoV-2 infection ranged from 43.0% to 59.1% across subgroups of age, sex, race/ethnicity, history of SARS-CoV-2 infection, pregnancy, and comorbidities (Table 2). Point estimates of the 3-dose rVE were higher against COVID-19 infection and hospitalization in the first 3 months, compared to 3–6 months after the 3^rd dose (Table 3).

Conclusion

Three doses of mRNA-1273 provide additional protection against SARS-CoV-2 infection and severe outcomes for IC individuals, compared to 2 doses, highlighting the importance of completing 3-doses for IC populations. However, possible waning of protection against SARS-CoV-2 infection and severe outcomes after 3 months supports the ACIP recommendation of a booster dose at least 3 months after the 3^rd primary series dose for adequate protection of IC individuals.

Disclosures

Jennifer H. Ku, PhD MPH, GSK: Grant/Research Support|Moderna: Grant/Research Support Lina S. Sy, MPH, Dynavax: Grant/Research Support|Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support|Seqirus: Grant/Research Support Lei Qian, PhD, Dynavax: Grant/Research Support|Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support Bradley Ackerson, MD, Dynavax: Grant/Research Support|Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support|Seqirus: Grant/Research Support Yi Luo, PhD, Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support|Seqirus: Grant/Research Support Julia Tubert, MPH, Moderna: Grant/Research Support|Pfizer: Grant/Research Support Gina Lee, MPH, Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support Ana Florea, PhD MPH, Gilead: Grant/Research Support|GSK: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support Carla Talarico, PhD, Moderna: Employee of and a shareholder in Moderna Inc. Sijia Qiu, MS, Dynavax: Grant/Research Support|Moderna: Grant/Research Support Yun Tian, MS, Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support Hung Fu Tseng, PhD MPH, GSK: Grant/Research Support|Janssen: Advisor/Consultant|Moderna: Grant/Research Support|Pfizer: Advisor/Consultant|Seqirus: Grant/Research Support.

1097. Risk of Severe COVID-19 Disease in Individuals with Down syndrome: a Matched Cohort Study from a Large, Integrated Health Care System

Background

Down syndrome (DS) is associated with an increased risk of infections attributed to immune defects. Whether individuals with DS are at an increased risk of severe COVID-19 remains unclear.

Methods

In a matched cohort study, we evaluated the risk of COVID-19 infection and severe COVID-19 disease in individuals with DS and their matched counterparts in a pre-COVID-19 vaccination period at Kaiser Permanente Southern California. Multivariable Cox proportion hazard regression was used to investigate associations between DS and risk of COVID-19 infection and severe COVID-19 disease.

Results

Our cohort included 2,541 individuals with DS and 10,164 without DS matched on age, sex, and race/ethnicity (51.6% female, 53.3% Hispanic, median age 25 years [interquartile range 14 – 38]), with pulmonary disease as the most common comorbidity (13.1%) followed by diabetes (5.4%). While the rate of COVID-19 infection in individuals with DS was 32% lower than their matched counterparts (adjusted hazard ratio [aHR] 0.68, 95% CI: 0.56-0.83), the rate of severe COVID-19 disease was 6-fold higher (aHR 6.14, 95% CI: 1.87-20.16) (Table 1). The Kaplan-Meier plot demonstrated similar cumulative incidence for those with and without DS at the beginning of the pandemic, followed by a rate increase in July 2020 (at 4 months of follow-up), and in November 2020 (at 8 months of follow-up) (Figure 1), after which the cumulative incidence for those with DS was consistently higher. Figure 2 demonstrated consistently higher cumulative incidence estimates of COVID-19 hospitalization for those with DS than those without. Table 1.Incidence rates and hazard ratios of COVID-19 infection, severe COVID-19 disease and COVID-19 hospitalization mortality among 2,541 individuals with Down Syndrome and 10,164 matched counterparts without Down Syndrome at Kaiser Permanente Southern California, 03/01/2020 - 12/31/2020

aAdjusted for covariates: body mass index, smoking, number of outpatient visits, number of emergency department visits, number of hospitalizations, frailty status based on frailty index (yes/no), all baseline comorbidities, and medical center area.

Abbreviations: DS = Down Syndrome; non-DS = matched counterparts without Down Syndrome; CI = confidence interval Figure 1.Cumulative incidence estimates of COVID-19 infection by Down syndrome status, Kaiser Permanente Southern California, 03/01/2020 - 12/31/2020Figure 2.Cumulative incidence estimates of COVID-19 hospitalization by Down syndrome status, Kaiser Permanente Southern California, 03/01/2020 - 12/31/2020

Conclusion

Although the risk of COVID-19 infection is lower, the risk of severe disease is higher in individuals with DS compared to their matched counterparts. Better infection monitoring, early treatment, and promotion of vaccine for COVID-19 are warranted for DS populations.

Disclosures

Jennifer H. Ku, PhD MPH, GSK: Grant/Research Support|Moderna: Grant/Research Support Myron J. Levin, MD, Curevo: Advisor/Consultant|Merck: Advisor/Consultant|Pfizer: Advisor/Consultant|seqirus: Advisor/Consultant|SmithKline Beecham: Grant/Research Support Yi Luo, PhD, Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support|Seqirus: Grant/Research Support Ana Florea, PhD MPH, Gilead: Grant/Research Support|GSK: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support Yun Tian, MS, Glaxosmithkline: Grant/Research Support|Moderna: Grant/Research Support Hung Fu Tseng, PhD MPH, GSK: Grant/Research Support|Janssen: Advisor/Consultant|Moderna: Grant/Research Support|Pfizer: Advisor/Consultant|Seqirus: Grant/Research Support.

Kawasaki Disease Following the 13-valent Pneumococcal Conjugate Vaccine and Rotavirus Vaccines

BACKGROUND

Temporal associations between Kawasaki disease (KD) and childhood vaccines have been reported. Limited data on KD following 13-valent pneumococcal conjugate (PCV13) and rotavirus vaccines are available.

METHODS

We conducted a self-controlled risk interval study using Vaccine Safety Datalink electronic health record data to investigate the risk of KD following PCV13 and rotavirus vaccines in children <2 years of age who were born from 2006 to 2017. All hospitalized KD cases identified by International Classification of Diseases diagnosis codes that fell within predefined risk (days 1-28 postvaccination) and control (days 29-56 for doses 1 and 2, and days 43-70 for doses 3 and 4) intervals were confirmed by manual chart review.

RESULTS

During the study period, 655 cases of KD were identified by International Classification of Diseases codes. Of these, 97 chart-confirmed cases were within risk or control intervals. In analyses, the age-adjusted relative risk for KD following any dose of PCV13 was 0.75 (95% confidence interval, 0.47-1.21). Similarly, the age-adjusted relative risk for KD following any dose of rotavirus vaccine was 0.66 (95% CI, 0.40-1.09). Overall, there was no evidence of an elevated risk of KD following PCV13 or rotavirus vaccines by dose. In addition, no statistically significant temporal clustering of KD cases was identified during days 1 to 70 postvaccination.

CONCLUSIONS

PCV13 and rotavirus vaccination were not associated with an increased risk of KD in children <2 years of age. Our findings provide additional evidence for the overall safety of PCV13 and rotavirus vaccines.

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.

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.

Risk of severe COVID-19 disease in individuals with Down syndrome: a matched cohort study from a large, integrated health care system

Background

Down syndrome (DS) is associated with an increased risk of infections attributed to immune defects. Whether individuals with DS are at an increased risk of severe coronavirus disease 2019 (COVID-19) remains unclear.

Methods

In a matched cohort study, we evaluated the risk of COVID-19 infection and severe COVID-19 disease in individuals with DS and their matched counterparts in a pre-COVID-19 vaccination period at Kaiser Permanente Southern California. Multivariable Cox proportion hazard regression was used to investigate associations between DS and risk of COVID-19 infection and severe COVID-19 disease.

Results

Our cohort included 2541 individuals with DS and 10 164 without DS matched on age, sex, and race/ethnicity (51.6% female, 53.3% Hispanic, median age 25 years [interquartile range, 14–38]). Although the rate of COVID-19 infection in individuals with DS was 32% lower than their matched counterparts (adjusted hazard ratio [aHR], 0.68; 95% confidence interval [CI], .56–.83), the rate of severe COVID-19 disease was 6-fold higher (aHR, 6.14; 95% CI, 1.87–20.16).

Conclusions

Although the risk of COVID-19 infection is lower, the risk of severe disease is higher in individuals with DS compared with their matched counterparts. Better infection monitoring, early treatment, and promotion of vaccine for COVID-19 are warranted for DS populations.

Safety of tetanus, diphtheria, acellular pertussis (Tdap) vaccination during pregnancy

The objective of this study was to evaluate the safety of prenatal tetanus, diphtheria, acellular pertussis (Tdap) vaccination. This cohort study was conducted among pregnant members at Kaiser Permanente Southern California (KPSC). The exposed cohort consisted of women who received Tdap vaccine on or after the 27th week of pregnancy between January 2018 and January 2019. The unexposed cohort consisted of matched women who were pregnant between January 2012 and December 2014 and were not vaccinated with any Tdap vaccine throughout their pregnancy. Maternal and infant characteristics and pre-specified endpoints were collected through automated data and review of the electronic health records. Unadjusted and adjusted relative risks (aRRs) with confidence intervals (CIs) were estimated by Poisson regression. Non-inferiority testing (i.e., to rule out a two-fold increase) was conducted for primary endpoints with adjustment for multiplicity. Superiority testing was conducted without multiplicity adjustment for secondary endpoints. The analysis consisted of 16,606 pairs of Tdap recipients and unexposed pregnant women. For the primary endpoints, the aRR for preeclampsia/eclampsia was 1.38 (98.75% CI:1.21-1.58) and the aRR for intrauterine infection was 1.28 (98.75% CI:1.12-1.47). These increases were consistent with the background increasing trend of these diagnoses among all pregnant women at KPSC since 2011, and the upper limit of the 98.75% CI of both aRRs did not exceed the pre-specified threshold of 2. No increased risks of small for gestational age (aRR = 1.04, 98.75% CI:0.94-1.16) or preterm delivery (aRR = 0.71, 98.75% CI:0.64-0.78) were observed. No evidence of increased risks for secondary endpoints, including poor fetal growth, preterm pre-labor rupture of membranes, stillbirth/fetal death, placental abruption, transfusion during delivery hospitalization, and neonatal death, was observed. Prenatal Tdap vaccination after the 27th week of pregnancy was not associated with increased risks of pre-specified maternal and infant outcomes, supporting the safety of Tdap vaccination during pregnancy.

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.

Prenatal influenza vaccination or influenza infection and autism spectrum disorder in offspring

BACKGROUND

As prenatal vaccinations continue to be given more frequently, it is important to assess long-term safety events. This study investigates the association between prenatal influenza vaccination or infection and autism spectrum disorder (ASD) risk in offspring.

METHODS

Retrospective cohort study of mother-child pairs with deliveries 1/1/2011-12/31/2014 at Kaiser Permanente Southern California was performed. Children >1 year were followed through 12/31/2018. Maternal influenza vaccination or infection during pregnancy was obtained from electronic health records. ASD was defined by International Classification of Diseases, 9th/10th Revision codes after age 1 year. Cox proportional hazards models estimated the crude and inverse probability of treatment weighted (IPTW) hazard ratios (HR) for the association between maternal influenza vaccination or infection and ASD.

RESULTS

There were 84,739 mother-child pairs included in the final analytic sample. Maternal vaccination coverage increased slightly over time, from 52.7% for 2011 births to 59.6% for 2014 births. Of the 46,257 women vaccinated, 32.4% were vaccinated during the 1 st trimester, 41.8% during the 2 nd trimester, and 25.8% during the 3 rd trimester. ASD was diagnosed in 1,930 (2.3%) children. The IPTW analyses showed no association between prenatal influenza vaccination or infection and ASD in offspring (HR: 1.04, 95% confidence interval [CI]: 0.95, 1.13; HR: 1.12, 95% CI: 0.66, 1.89, respectively).

CONCLUSIONS

Prenatal influenza vaccination or infection was not associated with ASD risk in offspring. The findings support recommendations to vaccinate pregnant women to protect themselves and their infants, both of whom are vulnerable to severe morbidity following infection.

Herpes Zoster Following Recombinant Zoster Vaccine With or Without Concomitant Vaccination

Background

The 2-dose recombinant zoster vaccine (RZV) series is recommended for prevention of herpes zoster (HZ) in adults aged ≥50 years, but data are limited on the impact of concomitant administration with other vaccines on subsequent HZ risk.

Methods

This cohort study included Kaiser Permanente Southern California members aged ≥50 years who received 2 doses of RZV 4 weeks to ≤6 months apart during 1 April 2018–30 September 2019. RZV recipients with and without same-day concomitant vaccination for either RZV dose were followed up for incident HZ beginning 31 days after the second RZV dose until 30 September 2020. The hazard ratio (HR) for HZ comparing RZV recipients with and without concomitant vaccination was estimated using Cox proportional hazards regression, adjusting for confounders.

Results

RZV with and without concomitant vaccination was received by 12 898 and 28 353 individuals, respectively. HZ occurred among 41 individuals with concomitant vaccination (incidence rate, 2.2 [95% confidence interval {CI}, 1.6–3.0] per 1000 person-years) and 136 without concomitant vaccination (3.4 [95% CI, 2.9–4.0] per 1000 person-years). The adjusted HR for HZ comparing RZV recipients with and without concomitant vaccination was 0.75 (95% CI, .53–1.08).

Conclusions

HZ risk was not significantly different between RZV recipients with and without concomitant vaccination, supporting recommendations allowing for concomitant administration of RZV with other vaccines.

Real-world effectiveness of the mRNA-1273 vaccine against COVID-19: Interim results from a prospective observational cohort study

Background

Phase 3 trials found mRNA-1273 was highly effective in preventing COVID-19. We conducted a prospective cohort study at Kaiser Permanente Southern California (KPSC) to determine the real-world vaccine effectiveness (VE) of mRNA-1273 in preventing COVID-19 infection and severe disease.

Methods

For this planned interim analysis, individuals aged ≥18 years receiving 2 doses of mRNA-1273 ≥24 days apart (18/12/2020-31/03/2021) were 1:1 matched to randomly selected unvaccinated individuals by age, sex, and race/ethnicity, with follow-up through 30/06/2021. Outcomes were COVID-19 infection (SARS-CoV-2 positive molecular test or COVID-19 diagnosis code) or severe disease (COVID-19 hospitalization and COVID-19 hospital death). Adjusted hazard ratios (aHR) and confidence intervals (CI) for COVID-19 outcomes comparing vaccinated and unvaccinated individuals were estimated by Cox proportional hazards models accounting for multiple comparisons. Adjusted VE was calculated as (1-aHR)x100. Whole genome sequencing was performed on SARS-CoV-2 positive specimens from the KPSC population.

Findings

This analysis included 352,878 recipients of 2 doses of mRNA-1273 matched to 352,878 unvaccinated individuals. VE (99·3% CI) against COVID-19 infection was 87·4% (84·8–89·6%). VE against COVID-19 hospitalization and hospital death was 95·8% (90·7–98·1%) and 97·9% (66·9-99·9%), respectively. VE was higher against symptomatic (88·3% [98·3% CI: 86·1–90·2%]) than asymptomatic COVID-19 (72·7% [53·4–84·0%]), but was generally similar across age, sex, and racial/ethnic subgroups. VE among individuals with history of COVID-19 ranged from 8·2–33·6%. The most prevalent variants were Alpha (41·6%), Epsilon (17·5%), Delta (11·5%), and Gamma (9·1%), with Delta increasing to 54·0% of variants by June 2021.

Interpretation

These interim results provide reassuring evidence of the VE of 2 doses of mRNA-1273 across age, sex, and racial/ethnic subgroups, and against asymptomatic and symptomatic COVID-19, and severe COVID-19 outcomes. Among individuals with history of COVID-19, mRNA-1273 vaccination may offer added protection beyond immunity acquired from prior infection. Longer follow-up is needed to fully evaluate VE of mRNA-1273 against emerging SARS-CoV-2 variants.

Funding

Moderna Inc.

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 mRNA-1273 against delta, mu, and other emerging variants of SARS-CoV-2: test negative case-control study

OBJECTIVES

To evaluate the effectiveness of the mRNA-1273 vaccine against SARS-CoV-2 variants and assess its effectiveness against the delta variant by time since vaccination.

DESIGN

Test negative case-control study.

SETTING

Kaiser Permanente Southern California (KPSC), an integrated healthcare system.

PARTICIPANTS

Adult KPSC members with a SARS-CoV-2 positive test sent for whole genome sequencing or a negative test from 1 March 2021 to 27 July 2021.

INTERVENTIONS

Two dose or one dose vaccination with mRNA-1273 (Moderna covid-19 vaccine) ≥14 days before specimen collection versus no covid-19 vaccination.

MAIN OUTCOME MEASURES

Outcomes included infection with SARS-CoV-2 and hospital admission with covid-19. In pre-specified analyses for each variant type, test positive cases were matched 1:5 to test negative controls on age, sex, race/ethnicity, and specimen collection date. Conditional logistic regression was used to compare odds of vaccination among cases versus controls, with adjustment for confounders. Vaccine effectiveness was calculated as (1-odds ratio)×100%.

RESULTS

The study included 8153 cases and their matched controls. Two dose vaccine effectiveness was 86.7% (95% confidence interval 84.3% to 88.7%) against infection with the delta variant, 98.4% (96.9% to 99.1%) against alpha, 90.4% (73.9% to 96.5%) against mu, 96-98% against other identified variants, and 79.9% (76.9% to 82.5%) against unidentified variants (that is, specimens that failed sequencing). Vaccine effectiveness against hospital admission with the delta variant was 97.5% (92.7% to 99.2%). Vaccine effectiveness against infection with the delta variant declined from 94.1% (90.5% to 96.3%) 14-60 days after vaccination to 80.0% (70.2% to 86.6%) 151-180 days after vaccination. Waning was less pronounced for non-delta variants. Vaccine effectiveness against delta infection was lower among people aged ≥65 years (75.2%, 59.6% to 84.8%) than those aged 18-64 years (87.9%, 85.5% to 89.9%). One dose vaccine effectiveness was 77.0% (60.7% to 86.5%) against infection with delta.

CONCLUSIONS

Two doses of mRNA-1273 were highly effective against all SARS-CoV-2 variants, especially against hospital admission with covid-19. However, vaccine effectiveness against infection with the delta variant moderately declined with increasing time since vaccination.

Severe Morbidity and Short- and Mid- to Long-term Mortality in Older Adults Hospitalized with Respiratory Syncytial Virus Infection

BACKGROUND

We describe the clinical epidemiology and outcomes among a large cohort of older adults hospitalized with respiratory syncytial virus (RSV) infection in the United States.

METHODS

Hospitalized adults aged ≥60 years who tested positive for RSV between 1 January 2011 and 30 June 2015 were identified from Kaiser Permanente Southern California. Patient-level demographics, comorbidities, clinical presentation, utilization, complications, and mortality were evaluated.

RESULTS

There were 664 patients hospitalized with RSV (61% female, 64% aged ≥75 years). Baseline chronic diseases were prevalent (all >30%); 66% developed pneumonia, 80% of which were radiographically confirmed. Very severe tachypnea (≥26 breaths/minute) was common (56%); 21% required ventilator support and 18% were admitted to intensive care unit. Mortality during hospitalization was 5.6% overall (4.6% in 60-74 year olds and 6.1% in ≥75 year olds). Cumulative mortality within 1, 3, 6, and 12 months of admission was 8.6%, 12.3%, 17.2%, and 25.8%, respectively.

CONCLUSION

RSV infection in hospitalized older adults often manifested as severe, life-threatening lower respiratory tract illness with high rates of pneumonia, requirement for ventilatory support, and short- and long-term mortality. Increased recognition of the substantial RSV disease burden in adults will be important in evaluation and use of urgently needed interventions.

The Epidemiology of Herpes Zoster in Immunocompetent, Unvaccinated Adults ≥50 Years Old: Incidence, Complications, Hospitalization, Mortality, and Recurrence

Background

Data on the epidemiology of herpes zoster (HZ), particularly in the unvaccinated immunocompetent population, are needed to assess disease burden and the potential impact of vaccination.

Methods

The study at a large health care organization comprised: (1) incidence estimated from immunocompetent adults aged ≥50 years unvaccinated with zoster vaccine live who had incident HZ in 2011–2015; (2) proportion of HZ-related nonpain complications assessed by double abstraction of electronic health records (EHRs) of 600 incident patients 2011–2015; (3) HZ-related hospitalizations among HZ patients diagnosed in 2015; (4) HZ-related death determined from automated data and EHRs; and (5) recurrent HZ identified from a cohort initially diagnosed with HZ in 2007–2008 and followed through 2016.

Results

HZ incidence rate was 9.92/1000 person-years (95% confidence interval [CI], 9.82–10.01). Proportions of cutaneous, neurologic, and other complications were 6.40% (95% CI,1.73%–11.07%), 0.77% (95% CI, .00%–2.36%), and 1.01% (95% CI, .00%–2.93%), respectively. Only 0.86% of patients had an HZ-related hospitalization. The case-fatality rate was 0.04%. Recurrence rate was 10.96/1000 person-years (95% CI, 10.18–11.79) with 10-year recurrence risk of 10.26% (95% CI, 9.36%–11.23%).

Conclusions

These recent HZ epidemiology data among an immunocompetent, unvaccinated population measure real-world disease burden.

Completion of the two-dose recombinant zoster vaccine series in adults 50 years and older

BACKGROUND

In 2017, a new adjuvanted recombinant zoster vaccine (RZV) was recommended for adults ≥50 years as two-dose series 2-6 months apart. We evaluated two-dose RZV completion and factors associated with completion.

METHODS

The study included Kaiser Permanente Southern California members ≥50 years who received an RZV dose during April-November 2018 and had continuous membership 12 months before to 9 months after the first RZV dose. Completion was defined as receipt of the second dose ≥4 weeks to 9 months after the first dose (allowing 3-month grace period). Characteristics including age, sex, race/ethnicity, Medicaid status, neighborhood level income and education, comorbidities, history of zoster, health care utilization before and after the first dose, receipt of influenza vaccine, vaccination month (supply shortage proxy), concomitant vaccine, medical center, and medically attended reactions, pain, or gout after the first dose were compared between completers and non-completers. Adjusted odds ratios and 95% confidence intervals for factors associated with completion were estimated by multivariable logistic regression.

RESULTS

Among 31,120 first dose recipients, 67.2% completed the series within 9 months. In adjusted analyses, higher completion was associated with White compared with Black or Hispanic race/ethnicity, higher neighborhood income and education, no chronic pulmonary disease, diabetes, or dementia, more outpatient visits and fewer emergency department visits before or after the first dose, no hospitalizations after the first dose, receipt of influenza vaccine, receipt of the first dose in June-November rather than April-May 2018, and no concomitant vaccine with the first dose. Systemic reactions or pain after the first dose was not associated with completion.

CONCLUSION

Completion of RZV series appears suboptimal in the early phase of implementation. Despite similar accessibility in a health care system, completion varied by race/ethnicity, socioeconomic status, health status, and care seeking behavior, suggesting areas to target for improvement.

Text-Based Identification of Herpes Zoster Ophthalmicus With Ocular Involvement in the Electronic Health Record: A Population-Based Study

Background

Diagnosis codes are inadequate for accurately identifying herpes zoster ophthalmicus (HZO). Manual review of medical records is expensive and time-consuming, resulting in a lack of population-based data on HZO.

Methods

We conducted a retrospective cohort study, including 87 673 patients aged ≥50 years who had a new HZ diagnosis and associated antiviral prescription between 2010 and 2018. We developed and validated an automated natural language processing (NLP) algorithm to identify HZO with ocular involvement (ocular HZO). We compared the characteristics of NLP-identified ocular HZO, nonocular HZO, and non-HZO cases among HZ patients and identified the factors associated with ocular HZO among HZ patients.

Results

The NLP algorithm achieved 94.9% sensitivity and 94.2% specificity in identifying ocular HZO cases. Among 87 673 incident HZ cases, the proportion identified as ocular HZO was 9.0% (n = 7853) by NLP and 2.3% (n = 1988) by International Classification of Diseases codes. In adjusted analyses, older age and male sex were associated with an increased risk of ocular HZO; Hispanic and black race/ethnicity each were associated with a lower risk of ocular HZO compared with non-Hispanic white.

Conclusions

The NLP algorithm achieved high accuracy and can be used in large population-based studies to identify ocular HZO, avoiding labor-intensive chart review. Age, sex, and race were strongly associated with ocular HZO among HZ patients. We should consider these risk factors when planning for zoster vaccination.

Real-world evidence of quadrivalent meningococcal conjugate vaccine safety in the United States: a systematic review

Two quadrivalent meningococcal conjugate vaccines (MenACWY) that prevent invasive meningococcal disease caused by N. meningitidis serogroups A, C, Y, and W have been licensed in the U.S. in the past 10-15 years. We systematically reviewed published studies conducted in the U.S. to evaluate the real-world safety evidence of meningococcal conjugate vaccines. We performed a literature search in PubMed of publications from 01/01/2005 to 02/29/2020 and identified 18 studies meeting inclusion criteria. Populations included high-risk persons aged 2 months to 10 years, adolescents/adults aged ≥11 years, pregnant populations, and hematopoietic cell transplant recipients. We extracted information about study setting, study design, exposure, outcomes, comparison group, follow-up/look back period, study population, sample size, available demographic/indication information, results, key conclusion, and reference. These published studies found no new significant safety concerns related to MenACWY. Consideration for future research includes a post-licensure safety evaluation of a new MenACWY product approved in April 2020.

Developing algorithms for identifying major structural birth defects using automated electronic health data

PURPOSE

Given the 2015 transition to International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) diagnostic coding, updates to our previously published algorithms for major structural birth defects (BDs) were necessary. Aims of this study were to update, validate, and refine algorithms for identifying selected BDs, and then to use these algorithms to describe BD prevalence in the vaccine safety datalink (VSD) population.

METHODS

We converted our ICD-9-CM list of selected BDs to ICD-10-CM using available crosswalks with manual review of codes. We identified, chart reviewed, and adjudicated a sample of infants in the VSD with ≥2 ICD-10-CM diagnoses for one of seven common BDs. Positive predictive values (PPVs) were calculated; for BDs with suboptimal PPV, algorithms were refined. Final automated algorithms were applied to a cohort of live births delivered 10/1/2015-9/30/2017 at eight VSD sites to estimate BD prevalence. This research was approved by the HealthPartners Institutional Review Board, by all participating VSD sites, and by the CDC, with a waiver of informed consent.

RESULTS

Of 573 infants with ≥2 diagnoses for a targeted BD, on adjudication, we classified 399 (69.6%) as probable cases, 31 (5.4%) as possible cases and 143 (25.0%) as not having the targeted BD. PPVs for the final BD algorithms ranged from 0.76 (hypospadias) to 1.0 (gastroschisis). Among 212 857 births over 2 years following transition to ICD-10-CM coding, prevalence for the full list of selected defects in the VSD was 1.8%.

CONCLUSIONS

Algorithms can identify infants with selected BDs using automated healthcare data with reasonable accuracy. Our updated algorithms can be used in observational studies of maternal vaccine safety and may be adapted for use in other surveillance systems.

The Association of Prenatal Tetanus, Diphtheria, and Acellular Pertussis (Tdap) Vaccination With Attention-Deficit/Hyperactivity Disorder

As prenatal vaccinations become more prevalent, it is important to assess potential safety events. In a retrospective cohort study of Kaiser Permanente Southern California (Pasadena, California) mother-child pairs with birth dates during January 1, 2011-December 31, 2014, we investigated the association between prenatal tetanus, diphtheria, and acellular pertussis (Tdap) vaccination and risk of attention-deficit/hyperactivity disorder (ADHD) in offspring. Information on Tdap vaccination during pregnancy was obtained from electronic medical records. ADHD was defined by International Classification of Diseases codes (Ninth or Tenth Revision) and dispensed ADHD medication after age 3 years. Children were followed to the date of their first ADHD diagnosis, the end of Kaiser Permanente membership, or the end of follow-up (December 31, 2018). In Cox proportional hazards models, we estimated unadjusted and adjusted hazard ratios for the association between maternal Tdap vaccination and ADHD, with inverse probability of treatment weighting (IPTW) used to adjust for confounding. Of 128,756 eligible mother-child pairs, 85,607 were included in the final sample. The ADHD incidence rate was 3.41 per 1,000 person-years in the Tdap-vaccinated women and 3.93 per 1,000 person-years in the unvaccinated (hazard ratio = 1.01, 95% confidence interval: 0.88, 1.16). The IPTW-adjusted analyses showed no association between prenatal Tdap vaccination and ADHD in offspring (hazard ratio = 1.00, 95% confidence interval: 0.88, 1.14). In this study, prenatal Tdap vaccination was not associated with ADHD risk in offspring, supporting recommendations to vaccinate pregnant women.

Severe Morbidity and Mortality Associated With Respiratory Syncytial Virus Versus Influenza Infection in Hospitalized Older Adults

Background

Respiratory syncytial virus (RSV) is an important cause of serious respiratory illness in older adults. Comparison of RSV and influenza infection in hospitalized older adults may increase awareness of adult RSV disease burden.

Methods

Hospitalized adults aged ≥60 years who tested positive for RSV or influenza between 1 January 2011 and 30 June 2015 were identified from Kaiser Permanente Southern California electronic medical records. Baseline characteristics, comorbidities, utilization, and outcomes were compared.

Results

The study included 645 RSV- and 1878 influenza-infected hospitalized adults. Patients with RSV were older than those with influenza (mean, 78.5 vs 77.4 years; P = .035) and more likely to have congestive heart failure (35.3% vs 24.5%; P < .001) and chronic obstructive pulmonary disease (COPD) (29.8% vs 24.3%; P = .006) at baseline. In adjusted analyses, RSV infection was associated with greater odds of length of stay ≥7 days (odds ratio [OR] = 1.5; 95% confidence interval [CI], 1.2–1.8; P < .001); pneumonia (OR = 2.7; 95% CI, 2.2–3.2; P < .001); intensive care unit admission (OR = 1.3; 95% CI, 1.0–1.7; P = .023); exacerbation of COPD (OR = 1.7; 95% CI, 1.3–2.4; P = .001); and greater mortality within 1 year of admission (OR = 1.3; 95% CI, 1.0–1.6; P = .019).

Conclusions

RSV infection may result in greater morbidity and mortality among older hospitalized adults than influenza. Increased recognition of adult RSV disease burden will be important in the evaluation and use of new RSV vaccines and antivirals.

Differences in Estimates of Post-Herpetic Neuralgia Between Medical Chart Review and Self-Report

PURPOSE

Post-herpetic neuralgia (PHN) is a common herpes zoster (HZ) complication, where pain persists 90 days after the initial HZ diagnosis. Evaluating PHN risk is essential for determining the burden on patients and health-care systems, but research shows variable estimates. The extent to which these differences are related to the assessment method has not been examined. The purpose of this study is to compare the proportion of PHN among HZ patients measured by medical chart review and self-report surveys.

METHODS

PHN risk was assessed among a sample of Kaiser Permanente Southern California members with HZ. Chart reviews identified lingering pain 90-180 days post-HZ diagnosis and the Zoster Brief Pain Inventory was administered 90 days post-HZ diagnosis by telephone. Frequencies of PHN identified with each approach were cross-tabulated and stratified by sex, age group, and zoster vaccine live vaccination status.

RESULTS

Chart review and self-report were largely concordant (n=875, 89.20%); however, chart review yielded lower PHN risk overall and for the stratified subgroups. PHN from self-report was substantially higher (6.30-8.33%) among patients who were male, ≥70 years, or unvaccinated. Among those who typically seek care more often (female, younger, vaccinated), the discrepancy between each method was notably lower (1.60-2.92%).

CONCLUSION

Our findings suggest that chart review underestimates cases among those less likely to seek health care, including males, the elderly, and unvaccinated individuals. The agreement between the methods indicates that each can provide a reasonable approximation of PHN, but analyses should carefully control for health-care utilization.

2300. Incidence, Complications, and Recurrence of Herpes Zoster in Unvaccinated Adults ≥50 Years of Age

Background

More recent baseline epidemiological data for Herpes Zoster (HZ) in adults ≥ 50 years of age, obtained before the introduction of the adjuvanted Recombinant Zoster Vaccine (RZV), are needed for future evaluations of the impact of RZV on HZ epidemiology.

Methods

The study comprised five elements: (1) The incidence of HZ was estimated from immunocompetent adults ≥ 50 years of age not vaccinated with Zoster Vaccine Live who had incident HZ between 2011–2015. HZ was identified by International Classification of Diseases (ICD) codes from electronic health records (EHR) of 4.6 million Kaiser Permanente Southern California members; (2) Postherpetic neuralgia (PHN) was identified by validated survey and medical record review of laboratory-confirmed incident HZ cases recruited during 2012–2015 for HZ-related pain ≥ 90 days after initial HZ diagnosis; (3) HZ Ophthalmicus (HZO) with ocular complications was identified by ICD codes and keyword search in EHR among patients identified with HZO using a validated natural language processing algorithm; (4) The proportion of HZ-related non-PHN and non-HZO cutaneous, neurological or other complications was assessed by double abstraction of EHRs from a sample of 600 incident HZ cases; (5) Recurrent HZ was identified by having an HZ diagnosis with HZ antiviral medication ≥ 6 months after the most recent HZ diagnosis with HZ antiviral medication in a cohort initially diagnosed with HZ between 2007 and 2008 and followed through 2016.

Results

We identified 40,893 incident HZ cases with an overall incidence of 9.92 (95% confidence interval [CI]: 9.82–10.01) per 1000 person-years. The proportion of incident HZ cases with PHN and HZO with ocular involvement was 18.37% (95% CI: 14.90–21.84%) and 8.06% (95% CI: 7.80–8.32%), respectively. The proportion of cutaneous, neurological, and other complications was 7.20% (95% CI: 5.44–8.96%), 0.87% (95% CI: 0.79–0.95%), and 1.24% (95% CI: 1.15–1.33%), respectively. The incidence of recurrent HZ was 10.96/1000 person-years (95% CI: 10.18–11.79).

Conclusion

HZ is common among unvaccinated US adults ≥ 50 years of age, with PHN and HZO occurring most frequently among incident HZ cases.

Funding

GlaxoSmithKline Biologicals SA, GSK study identifier: HO-17-18378.

Disclosures

All authors: No reported disclosures.

Safety of quadrivalent meningococcal conjugate vaccine in infants and toddlers 2 to 23-months old

INTRODUCTION

The quadrivalent meningococcal conjugate vaccine MenACWY-CRM is recommended for 2-23 month-old infants/toddlers at increased risk for meningococcal disease. This study adds to the current knowledge of MenACWY-CRM safety among this age group in a clinical care setting.

METHODS

Kaiser Permanente Southern California members aged 2-23 months who received MenACWY-CRM between July 2014 and June 2017 were included. Electronic health records were searched for emergency department (ED) and hospitalization encounters, and diagnoses associated with these visits up to 6 months after each dose.

RESULTS

There were 138 infants/toddlers who received MenACWY-CRM, with 59.4% being African American and 66.7% receiving only one dose. Most infants either had a high-risk condition (i.e., anatomic/functional asplenia or DiGeorge syndrome) (42.0%), or a travel indication (54.3%). The incidence rate of ED visits was 0.6/person-year (95% confidence interval [CI]: 0.5-0.8), 0.4/person-year (CI: 0.3-0.5) for hospitalizations, and 0.1/person-year (CI: 0.1-0.3) for ED to hospital transfers. Overall, 29.0% of recipients had an incident diagnosis in the ED or hospital setting. Fever and acute upper respiratory infections were the most common diagnoses, with 46 out of 47 diagnoses occurring among infants with high-risk conditions.

CONCLUSIONS

Data from this descriptive observational study do not suggest safety concerns associated with MenACWY-CRM when used as part of clinical care of 2-23 month-old infants/toddlers indicated for vaccination.

Use of Real-world Evidence to Evaluate the Effectiveness of Herpes Zoster Vaccine

This article reviews the use of real-world evidence (RWE) from observational studies to evaluate herpes zoster vaccine effectiveness and complement clinical trial data that have known limitations. The use of RWE with appropriate study designs and cautious interpretation can be informative in decision-making. Understanding the advantages and limitations of studies yielding RWE can facilitate the critical evaluation of findings from different studies. This is a timely issue, as regulatory agencies are considering how RWE can contribute to the assessment of effectiveness in regulatory decision-making.

Patient report of herpes zoster pain: Incremental benefits of zoster vaccine live

INTRODUCTION

Pain following herpes zoster (HZ) can persist for months and negatively impact quality of life. To evaluate the effect of zoster vaccine live (ZVL) on progression of pain following HZ, we conducted a prospective cohort study of HZ cases at Kaiser Permanente Southern California.

METHODS

ZVL vaccinated and unvaccinated members aged ≥60 years with laboratory-confirmed HZ from January 18, 2012 to February 26, 2015 were followed up within 5 days of HZ diagnosis, and at 30, 60, and 90 days after diagnosis. Pain was assessed with the Zoster Brief Pain Inventory (ZBPI) on a 0-10 scale, using cut-points of ≥3, ≥5, and ≥7, with postherpetic neuralgia (PHN) defined as pain ≥3 at 90 days. Log binomial regression was used to estimate adjusted risk ratios (aRRs) and 95% confidence intervals (CIs) associated with pain, comparing vaccinated versus unvaccinated HZ patients.

RESULTS

We interviewed 509 vaccinated and 509 unvaccinated HZ patients. ZVL was associated with significantly lower risks of HZ-related pain at all time-points. The risk of PHN in vaccinated and unvaccinated patients, respectively, was 9.2% and 15.4% (aRR = 0.594, 95% CI: 0.413, 0.854); 2.0% and 4.8% of these patients reported pain ≥7 (aRR = 0.332, 95% CI: 0.153, 0.721). Irrespective of vaccination, the risk of PHN was lower in adults aged <70 years versus those ≥70 years and was similar or lower in females versus males.

CONCLUSION

We used laboratory confirmation of HZ cases and patient survey to show that aside from preventing HZ, ZVL reduced HZ-related pain and prevented PHN among vaccine recipients who experienced HZ. Observational studies will be needed to evaluate long-term effectiveness of the new recombinant zoster vaccine and its benefits in protecting patients against PHN.

The use of natural language processing to identify Tdap-related local reactions at five health care systems in the Vaccine Safety Datalink

OBJECTIVE

Local reactions are the most common vaccine-related adverse event. There is no specific diagnosis code for local reaction due to vaccination. Previous vaccine safety studies used non-specific diagnosis codes to identify potential local reaction cases and confirmed the cases through manual chart review. In this study, a natural language processing (NLP) algorithm was developed to identify local reaction associated with tetanus-diphtheria-acellular pertussis (Tdap) vaccine in the Vaccine Safety Datalink.

METHODS

Presumptive cases of local reactions were identified among members ≥ 11 years of age using ICD-9-CM codes in all care settings in the 1-6 days following a Tdap vaccination between 2012 and 2014. The clinical notes were searched for signs and symptoms consistent with local reaction. Information on the timing and the location of a sign or symptom was also extracted to help determine whether or not the sign or symptom was vaccine related. Reactions triggered by causes other than Tdap vaccination were excluded. The NLP algorithm was developed at the lead study site and validated on a stratified random sample of 500 patients from five institutions.

RESULTS

The NLP algorithm achieved an overall weighted sensitivity of 87.9%, specificity of 92.8%, positive predictive value of 82.7%, and negative predictive value of 95.1%. In addition, using data at one site, the NLP algorithm identified 3326 potential Tdap-related local reactions that were not identified through diagnosis codes.

CONCLUSION

The NLP algorithm achieved high accuracy, and demonstrated the potential of NLP to reduce the efforts of manual chart review in vaccine safety studies.

Safety of Influenza Vaccination Administered During Hospitalization

OBJECTIVE

To determine whether influenza vaccination during hospitalization increases health care utilization, fever, and infection evaluations postdischarge.

PATIENTS AND METHODS

This retrospective cohort study conducted at Kaiser Permanente Southern California included patients aged 6 months or older hospitalized in a Kaiser Permanente Southern California facility with admission and discharge dates between September 1 and March 31 of the following calendar year, from 2011 to 2014. All influenza vaccinations administered during the period of August 1 to April 30 for influenza seasons 2011-2012, 2012-2013, and 2013-2014 were identified. We compared the risk of outcomes of interest between those who received influenza vaccination during their hospitalization vs those who were never vaccinated that season or were vaccinated at other times using propensity score analyses with inverse probability of treatment weighting. Outcomes of interest included rates of outpatient and emergency department visits, readmissions, fever, and clinical laboratory evaluations for infection (urine, blood, and wound culture; complete blood cell count) in the 7 days following discharge.

RESULTS

We included in the study 290,149 hospitalizations among 255,737 patients. In adjusted analyses, we found no increased risk of readmissions (relative risk [RR], 0.88; 95% CI, 0.83-0.95), outpatient visits (RR, 0.97; 95% CI, 0.95-0.99), fever (RR, 0.80; 95% CI, 0.68-0.93), and clinical evaluations for infection (RR, 0.95; 95% CI, 0.92-0.98) among those vaccinated during hospitalization compared with those who were never vaccinated or were vaccinated at other times.

CONCLUSION

Our findings provide reassurance about the safety of influenza vaccination during hospitalization. Every contact with a health care professional, including during a hospitalization, is an opportunity to vaccinate.

Testing for Coccidioidomycosis among Community-Acquired Pneumonia Patients, Southern California, USA1

We conducted a cohort study to identify characteristics associated with testing for, and testing positive for, coccidioidomycosis among patients with community-acquired pneumonia in southern California, USA. Limited and delayed testing probably leads to underdiagnosis among non-Hispanic black, Filipino, or Hispanic patients and among high-risk groups, including persons in whom antimicrobial drug therapy has failed.

2461. Safety of Quadrivalent Meningococcal Polysaccharide Diphtheria Toxoid-Conjugate Vaccine in Adolescents

Background

The first quadrivalent meningococcal conjugate vaccine (MenACWY-D) was recommended for use in adolescents in 2005. Soon after, case reports of Guillain-Barre syndrome (GBS) following vaccination prompted subsequent studies, with a meta-analysis concluding that the attributable risk of GBS after MenACWY-D is unlikely to exceed 1 case per million vaccinations. We conducted a retrospective cohort study in the Vaccine Safety Datalink to assess the risk of 10 outcomes, including GBS, following MenACWY-D.

Methods

We included adolescents (aged 11–18 years) vaccinated with MenACWY-D during the years 2005–2014. We identified pre-specified outcomes using ICD-9 (International Classification of Disease, version 9) codes. We used automated data only for Bell’s palsy, fever, seizure and syncope, and we confirmed incident cases by medical record review for acute disseminated encephalomyelitis (ADEM), acute transverse myelitis (ATM), anaphylaxis, chronic inflammatory demyelinating polyneuropathy (CIDP), GBS and Henoch-Schönlein purpura (HSP). We used a self-controlled risk interval design to estimate relative risk (RR).

Results

Following 1.4 million doses of MenACWY-D, we detected increased risks for fever in the 1–6 days following vaccination (RR 1.5, 95% confidence interval [CI] 1.3–1.7) and syncope on the day of vaccination (RR 5.8, 95% CI 4.1–8.3), but not for seizures (RR 1.1, 95% CI 0.7–1.9) or Bell’s palsy (RR 1.1, 95% CI 0.8–1.5). We detected no cases in the post-vaccination risk intervals for CIDP, ADEM or ATM. We detected few cases of the other outcomes resulting in relatively unstable RR estimates: anaphylaxis (RR 1.9, 95% CI 0.5–7.1), GBS (RR 2.5, 95% CI 0.6–10.0) and HSP (RR 1.6, 95% CI 0.7–3.3). We estimated that the attributable risk of GBS was 1.5 cases per million vaccinations (upper bound of one-sided 95% CI, 4.9).

Conclusion

In a large retrospective cohort, we detected increased risks for syncope and fever, but not seizures or Bell’s palsy, following vaccination with MenACWY-D. Other outcomes were rare. Our findings, consistent with previous studies, suggest that the increased risk of GBS, if any, is likely small (<5 excess cases of GBS per million vaccinations).

Disclosures

N. P. Klein, Sanofi Pasteur: Investigator, Research grant. Merck: Investigator, Research grant. GSK: Investigator, Research grant. Pfizer: Investigator, Research support. Protein Science: Investigator, Research grant. MedImmune: Investigator, Research grant. Dynavax: Research Contractor, Grant recipient. M. L. Jackson, Novartis: Grant Investigator, Research support.

2284. Ten-Year Effectiveness of Live Virus Herpes Zoster Vaccine

Background

Although recombinant zoster vaccine (RZV) is recommended preferentially in adults aged ≥50 years in the United States, zoster vaccine live (ZVL) remains a recommended vaccine in immunocompetent adults aged ≥60 years and is currently being used in many countries around the world. Assessing the long-term effectiveness of both vaccines is critical for determining vaccine policy, including the optimal age to begin vaccination and the need for and timing of revaccination. We evaluated the long-term effectiveness of ZVL in adults ≥ 60 years old in the United States.

Methods

We conducted a retrospective cohort study at Kaiser Permanente Southern California (KPSC). The exposed cohort included KPSC members ≥60 years vaccinated with ZVL during 1/1/2007- 12/31/2014. Three unvaccinated members were matched to each vaccinated member on age, sex, and length of membership. Individuals were followed to 6/30/2017. Electronic health records were used to identify incident herpes zoster (HZ). The effectiveness of ZVL and its 95% confidence interval (CI) at each year following vaccination was estimated.

Results

The number of HZ cases was 7,783 in 923,176 person-years (8.4 per 1,000; 95% CI, 8.2–8.6 per 1,000) among vaccinated persons and 26,813 in 1,964,974 person-years (13.6 per 1,000; 95% CI, 13.5–13.8 per 1,000) among unvaccinated persons. The HZ incidence rate ratio, comparing the vaccinated to the unvaccinated, was 0.62 (95% CI, 0.60–0.63). The effectiveness by year after vaccination decreased each year of follow-up from 65.8% (95% CI, 63.2%-68.2%) in the first year, 49.3% (95% CI, 45.7%-52.6%) in the second, 32.0% (95% CI, 24.1%-39.1%) to 36.8% (95% CI, 32.3%-40.9%) in the third - sixth year, and 22.0% (95% CI, -2.5%- 40.6%) to 23.6% (95% CI, 13.4%-32.7%) in the seventh - 10^th year. A similar pattern was seen between those 60–69 years and ≥70 years of age.

Conclusion

The effectiveness of ZVL declined from 66% in the first year to 22% in the 10^th year after vaccination. This 10-year effectiveness study of ZVL provides insights into a revaccination strategy and need for a more effective and durable vaccine. Studies of long-term effectiveness of RZV are also warranted.

Disclosures

All authors: No reported disclosures.

Prenatal Tetanus, Diphtheria, Acellular Pertussis Vaccination and Autism Spectrum Disorder

: media-1vid110.1542/5803567555001PEDS-VA_2018-0120Video Abstract BACKGROUND: Increasing vaccination of pregnant women makes it important to assess safety events potentially linked to prenatal vaccination. This study investigates the association between prenatal tetanus, diphtheria, acellular pertussis (Tdap) vaccination and autism spectrum disorder (ASD) risk in offspring.

METHODS

This is a retrospective cohort study of mother-child pairs with deliveries January 1, 2011 to December 31, 2014 at Kaiser Permanente Southern California hospitals. Maternal Tdap vaccination from pregnancy start to delivery date was obtained from electronic medical records. A diagnosis of ASD was obtained by using International Classification of Diseases, Ninth and Tenth Revision codes. Children were managed from birth to first ASD diagnosis, end of membership, or end of follow-up (June 30, 2017). Cox proportional hazards models estimated the unadjusted and adjusted hazard ratios (HRs) for the association between maternal Tdap vaccination and ASD, with inverse probability of treatment weighting to adjust for confounding.

RESULTS

Women vaccinated were more likely to be Asian American or Pacific Islander, be nulliparous, have a higher education, receive influenza vaccination prenatally, and give birth at term. ASD was diagnosed in 1341 (1.6%) children, and the incidence rate was 3.78 per 1000 person years in the Tdap exposed and 4.05 per 1000 person years in the unexposed group (HR: 0.98, 95% confidence interval: 0.88-1.09). The inverse probability of treatment weighting-adjusted analyses revealed that prenatal Tdap vaccination was not associated with an increased ASD risk (HR: 0.85, 95% confidence interval: 0.77-0.95).

CONCLUSIONS

Prenatal Tdap vaccination was not associated with an increased ASD risk. We support recommendations to vaccinate pregnant women to protect infants, who are at highest risk of death after pertussis infection.

Real-World Evidence for Regulatory Decisions: Concomitant Administration of Zoster Vaccine Live and Pneumococcal Polysaccharide Vaccine

The US Food and Drug Administration is charged with expanding the use of real-world evidence for regulatory decisions. As a test case for real-world evidence to support regulatory decisions, we present the scenario of concomitant vaccination with zoster vaccine live (ZVL) and 23-valent pneumococcal polysaccharide vaccine (PPSV23). The prescribing information states that these vaccines should not be given concurrently, based on a small trial using varicella zoster virus antibody levels as a correlate of ZVL efficacy, even though ZVL protects against herpes zoster via cell-mediated immunity. We conducted an observational cohort study involving more than 35,000 members of Kaiser Permanente Southern California receiving concomitant ZVL and PPSV23 versus PPSV23 prior to ZVL. Occurrence of herpes zoster was assessed through electronic health records from January 1, 2007, to June 30, 2016. The adjusted hazard ratio comparing incidence rates of herpes zoster in the concomitant vaccination cohort and the prior vaccination cohort was 1.04 (95% confidence interval: 0.92, 1.16). This real-world evidence study provides direct evidence for a lack of vaccine interference, relying on herpes zoster occurrence rather than an intermediate marker of immunity. Real-world evidence is essential for regulators and policy makers in addressing evidentiary gaps regarding safety, effectiveness, compliance, and vaccine interactions for the new recombinant zoster vaccine.

Impact of an electronic medical record reminder on hepatitis B vaccine initiation and completion rates among insured adults with diabetes mellitus

OBJECTIVE

The Advisory Committee on Immunization Practices recommends Hepatitis B (HepB) vaccine for previously unvaccinated adults <60 years with diabetes mellitus. This observational retrospective cohort study assessed the impact of implementing electronic provider reminders on HepB vaccine initiation and 3-dose series completion rates among insured adults with diabetes aged 19-59 years old.

RESEARCH DESIGN AND METHODS

Difference-in-difference (DID) analyses compared changes in vaccine initiation and completion rates (ratio of the rate ratio [RRR] and 95% confidence interval [CI]) during 12 months pre- and post-implementation between intervention and control sites. We examined trends in vaccine initiation and completion rates by plotting monthly rates during the study period. We also calculated the overall HepB vaccine coverage rates with 95% CI among all adults with diabetes aged 19-59 years old at the start and end date of the study period.

RESULTS

Baseline HepB vaccine initiation and completion rates were similar at both the intervention and control sites. Gender, age, and race/ethnicity distributions within both sites were similar during the 12 months pre- and post-implementation. DID analyses demonstrated statistically significant differences in the changes of the annual vaccine initiation rates (RRR: 70.7, 95% CI: 62.8-79.6) and the third dose completion rates (RRR = 18.7, 95% CI: 14.2-24.8) between the two sites. The coverage increased significantly at the intervention site while it remained low at the control site.

CONCLUSIONS

Use of provider reminders is highly effective in increasing both HepB vaccine initiation and series completion rates among adults with diabetes.