Swift, Melanie D.

Abstract COVID-19 vaccines are effective, but breakthrough infections have been increasingly reported. We conducted a test-negative case-control study to assess the durability of protection against symptomatic infection after vaccination with mRNA-1273. We fit conditional logistic regression (CLR) models stratified on residential county and calendar date of SARS-CoV-2 PCR testing to assess the association between the time elapsed since vaccination and the odds of symptomatic infection, adjusted for several covariates. There were 2,364 symptomatic individuals who had a positive SARS-CoV-2 PCR test after full vaccination with mRNA-1273 (“cases”) and 12,949 symptomatic individuals who contributed 15,087 negative tests after full vaccination (“controls”). The odds of symptomatic infection were significantly higher 250 days after full vaccination compared to the date of full vaccination (Odds Ratio [OR]: 2.47, 95% confidence interval [CI]: 1.19–5.13). The odds of non-COVID-19 associated hospitalization and non-COVID-19 pneumonia (negative control outcomes) remained relatively stable over the same time interval (Day 250 ORNon-COVID Hospitalization: 0.68, 95% CI: 0.47–1.0; Day 250 ORNon-COVID Pneumonia: 1.11, 95% CI: 0.24–5.2). The odds of symptomatic infection remained significantly lower almost 300 days after the first mRNA-1273 dose as compared to 4 days after the first dose, when immune protection approximates the unvaccinated state (OR: 0.26, 95% CI: 0.17–0.39). Low rates of COVID-19 associated hospitalization or death in this cohort precluded analyses of these severe outcomes. In summary, mRNA-1273 robustly protected against symptomatic SARS-CoV-2 infection at least 8 months after full vaccination, but the degree of protection waned over this time period.

Abstract As of 2021 November 29, booster vaccination against SARS-CoV-2 infection has been recommended for all individuals aged 18 years and older in the United States. A key reason for this recommendation is the expectation that a booster vaccine dose can alleviate observed waning of vaccine effectiveness (VE). Although initial reports of booster effectiveness have been positive, the level of protection from booster vaccination is unclear. We conducted two studies to assess the impact of booster vaccination, with BNT162b2 or mRNA-1273, on the incidence of SARS-CoV-2 infection between August and December 2021. We first compared SARS-CoV-2 infection incidence in cohorts of 3-dose vaccine recipients to incidence in matched cohorts of 2-dose vaccine recipients (cohort size = 24,539 for BNT162b2 and 14,004 for mRNA-1273). Additionally, we applied a test-negative study design to compare the level of protection against symptomatic infection in 3-dose recipients to that observed in recent 2-dose primary vaccine series recipients. The 3-dose recipients experienced a significantly lower incidence rate of SARS-CoV-2 infection than the matched 2-dose cohorts (BNT162b2 Incidence Rate Ratio: 0.11, 95% CI: 0.09 to 0.13 and mRNA-1273 IRR: 0.11, 95% CI: 0.08 to 0.15). Results from the test-negative study showed the third vaccine dose mitigated waning of VE, with the risk of symptomatic infection in 3-dose recipients being comparable to that observed 7 to 73 days after the primary vaccine series. These results show that 3-dose vaccine regimens with BNT162b2 or mRNA-1273 are effective at reducing SARS-CoV-2 infection and support the widespread administration of booster vaccine doses.

Abstract We report the utility of rapid antigen tests (RAgT) in a cohort of US healthcare personnel with coronavirus disease 2019 (COVID-19) infection who met symptom criteria to return to work at day 5 or later of isolation. In total, 11.9% of initial RAgT were negative. RAgT can be helpful to guide return to work decisions.

Abstract Background Myocarditis following coronavirus disease 2019 (COVID-19) mRNA vaccines (Pfizer-BioNTech and Moderna) has been increasingly reported. Incidence rates in the general population are lacking, with pericarditis rather than myocarditis diagnostic codes being used to estimate background rates. This comparison is critical for balancing the risk of vaccination with the risk of no vaccination. Methods A retrospective case series was performed using the Mayo Clinic COVID-19 Vaccine Registry. We measured the incidence rate ratio (IRR) for myocarditis temporally related to COVID-19 mRNA vaccination compared with myocarditis in a comparable population from 2016 through 2020. Clinical characteristics and outcomes of the affected patients were collected. A total of 21 individuals were identified, but ultimately 7 patients met the inclusion criteria for vaccine-associated myocarditis. Results The overall IRR of COVID-19–related myocarditis was 4.18 (95% confidence interval [CI], 1.63–8.98), which was entirely attributable to an increased IRR among adult males (IRR, 6.69; 95% CI, 2.35–15.52) compared with females (IRR 1.41; 95% CI, .03–8.45). All cases occurred within 2 weeks of a dose of the COVID-19 mRNA vaccine, with the majority occurring within 3 days (range, 1–13) following the second dose (6 of 7 patients, 86%). Overall, cases were mild, and all patients survived. Conclusions Myocarditis is a rare adverse event associated with COVID-19 mRNA vaccines. It occurs in adult males with significantly higher incidence than in the background population. Recurrence of myocarditis after a subsequent mRNA vaccine dose is not known at this time.

Abstract In a large cohort of United States healthcare personnel without prior coronavirus disease 2019 (COVID-19) infection, 94 382 doses of messenger RNA (mRNA) COVID-19 vaccine were administered to 49 220 individuals. The adjusted vaccine effectiveness following 2 doses of each of the 2 available brands of mRNA vaccine exceeded 96%.

Abstract Background Several vaccines are now available under emergency use authorization in the United States and have demonstrated efficacy against symptomatic COVID-19. Vaccine impact on asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is largely unknown. Methods We conducted a retrospective cohort study of consecutive, asymptomatic adult patients (n = 39 156) within a large US healthcare system who underwent 48 333 preprocedural SARS-CoV-2 molecular screening tests between 17 December 2020 and 8 February 2021. The primary exposure of interest was vaccination with ≥1 dose of an mRNA COVID-19 vaccine. The primary outcome was relative risk (RR) of a positive SARS-CoV-2 molecular test among those asymptomatic persons who had received ≥1 dose of vaccine compared with persons who had not received vaccine during the same time period. RR was adjusted for age, sex, race/ethnicity, patient residence relative to the hospital (local vs nonlocal), healthcare system regions, and repeated screenings among patients using mixed-effects log-binomial regression. Results Positive molecular tests in asymptomatic individuals were reported in 42 (1.4%) of 3006 tests and 1436 (3.2%) of 45 327 tests performed on vaccinated and unvaccinated patients, respectively (RR, .44; 95% CI, .33–.60; P < .0001). Compared with unvaccinated patients, risk of asymptomatic SARS-CoV-2 infection was lower among those >10 days after the first dose (RR, .21; 95% CI, .12–.37; P < .0001) and >0 days after the second dose (RR, .20; 95% CI, .09–.44; P < .0001) in the adjusted analysis. Conclusions COVID-19 vaccination with an mRNA-based vaccine showed a significant association with reduced risk of asymptomatic SARS-CoV-2 infection as measured during preprocedural molecular screening. Results of this study demonstrate the impact of the vaccines on reduction in asymptomatic infections supplementing the randomized trial results on symptomatic patients.

Abstract Background US public health strategy for eliminating tuberculosis (TB) prioritizes treatment of latent TB infection (LTBI). Healthcare personnel (HCP) are less willing to accept treatment than other populations. Little is known about factors associated with HCP LTBI therapy acceptance and completion. Methods We conducted a retrospective chart review to identify all employees with LTBI at time of hire at a large academic medical center during a 10-year period. Personal demographics, occupational factors, and clinic visit variables were correlated with LTBI treatment acceptance and completion rates using multivariate logistic regression. Results Of 470 HCP with LTBI for whom treatment was recommended, 193 (41.1%) accepted treatment, while 137 (29.1%) completed treatment. Treatment adherence was better with 4 months of rifampin than 9 months of isoniazid (95% vs 68%, P < .005). Increased age of the healthcare worker was independently associated with lower rates of treatment acceptance (odds ratio [95% confidence interval]: 0.97 [0.94–0.99] per year), as was having an occupation of clinician (0.47 [0.26–0.85]) or researcher (0.34 [0.19–0.64]). Male gender was associated with higher treatment acceptance (1.90 [1.21–2.99]). Treatment completion was associated with being from a low- (9.49 [2.06–43.73]) or medium- (8.51 [3.93–18.44]) TB-burden country. Conclusions Geographic and occupational factors affect acceptance and completion of LTBI therapy. Short-course regimens may improve adherence. Physicians, researchers, and HCP from high-TB-burden countries have lower treatment rates than other HCP. Improving LTBI treatment in HCP will require attending to cultural and occupational differences.