Estimated Effectiveness of Prior SARS-CoV-2 BA.1 or BA.2 Infection and Booster Vaccination Against Omicron BA.5 Subvariant Infection

Jang, Eun Jung; Choe, Young June; Kim, Ryu Kyung; Lee, Sang‐Won; Park, Seon Kyeong; Park, Young-Joon

doi:10.1001/jamanetworkopen.2023.2578

Cited by 10 publications

(17 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…18,19 The proportion of previous Omicron BA.1/BA.2 infection was higher in controls than in breakthrough cases, consistent with the results of a previous study. 20 These results suggest that the Omicron BA.5 neutralizing capacity induced by previous Omicron BA.1/BA.2 infections lowers the risk of Omicron BA.5 infection among the three-dose recipients and is compatible with the findings of observational studies indicating that hybrid immunity (three vaccinations plus previous Omicron BA.1/BA.2 infection) has higher effectiveness against Omicron BA.5 infection than only three vaccinations. 20 We confirmed that Omicron BA.5 neutralizing antibody titers were modestly but significantly lower in cases than in controls in the analysis of infection-naïve vaccine recipients, suggesting that the level of humoral immunity induced by historical mRNA vaccine alone can also predict, albeit to a lesser extent than hybrid immunity, the infection risk of Omicron BA.5 with a high immune-evasive nature.…”

Section: Discussionsupporting

confidence: 85%

Pre-infection neutralizing antibodies, Omicron BA.5 breakthrough infection, and long COVID: a propensity score-matched analysis

Yamamoto

Matsuda

Maeda

et al. 2023

Preprint

View full text Add to dashboard Cite

Importance Investigating the role of pre–infection humoral immunity against Omicron BA.5 infection risk and long COVID development is critical to inform public health guidance. Objective To investigate the association between pre–infection immunogenicity after the third vaccine dose and the risks of Omicron BA.5 infection and long coronavirus disease. Design, Setting, and Participants This nested case–control analysis was conducted among tertiary hospital staff in Tokyo, Japan who donated blood samples in June 2022 (1 month before Omicron BA.5 dominant wave onset [July–September 2022]) approximately 6 months after receiving the third dose of the historical monovalent coronavirus disease 2019 mRNA vaccine. Exposures Live virus–neutralizing antibody titers against Wuhan and Omicron BA.5 (NT50) and anti–SARS–CoV–2 spike protein antibody titers with Abbott (AU/mL) and Roche (U/mL) assays at pre–infection. Main Outcomes and Measures Symptomatic SARS–CoV–2 breakthrough infections during the Omicron BA.5 dominant wave vs. undiagnosed controls matched using a propensity score. Incidence of long COVID (persistent symptoms ≥4 weeks after infection) among breakthrough infection cases. Results Anti–spike antibody titers were compared between 243 breakthrough infection cases and their matched controls among the 2360 staff members who met the criteria. Neutralizing antibodies in 50 randomly selected matched pairs were measured and compared. Pre–infection anti-spike and neutralizing antibody titers were lower in breakthrough cases than in undiagnosed controls. Neutralizing antibody titers against Wuhan and Omicron BA.5 were 64% (95% CI: 42–77) and 72% (95% CI: 53–83) lower, respectively, in breakthrough cases than in undiagnosed controls. Individuals with previous SARS-CoV-2 infections were more frequent among undiagnosed controls than breakthrough cases (19.3% vs. 4.1%), and their neutralizing antibody titers were higher than those of infection–naive individuals. Among the breakthrough cases, pre–infection antibody titers were not associated with the incidence of long COVID. Conclusions and Relevance Pre–infection immunogenicity against SARS–CoV–2 may play a role in protecting against the Omicron BA.5 infection, but not in preventing long COVID.

show abstract

Section: Discussionsupporting

confidence: 85%

Pre-infection neutralizing antibodies, Omicron BA.5 breakthrough infection, and long COVID: a propensity score-matched analysis

Yamamoto

Matsuda

Maeda

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

“…This is consistent with findings of other studies on mRNA vaccines, 2 suggesting that waning is general feature of SARS-CoV-2 vaccines. For inactivated SARS-CoV-2 vaccines, a previous study 32 suggested that there was no protection beyond 90 days after booster vaccination, but the protection remained significant within 120 days in our study. It is, however, unclear how long the protection will persist after booster vaccination.…”

Section: Comparisons With Previous Studies and Interpretationscontrasting

confidence: 74%

“…[25][26][27] For example, our estimate was much lower than that of an mRNA vaccine found in an RCT conducted during the Delta-predominant period (95.3%; 95% CI, 89.5%-98.3%), 28 but was closer to that of a recombinant protein vaccine (47.8%; 95% CI, 22.6%-64.7%) in another RCT 29 conducted during the Omicron-predominant period. Furthermore, previous general population studies 25,27,[30][31][32] reported that the effectiveness of a booster dose of an Model 1 (left) was adjusted for age, sex, health care practitioner, diabetes, hypertension, chronic kidney disease, stroke, cancer, interval between the first and second doses, and interval between the latest dose and last contact. Model 2 (right) was further adjusted for calendar time of last contact.…”

Section: Comparisons With Previous Studies and Interpretationsmentioning

confidence: 99%

Inactivated SARS-CoV-2 Vaccine Booster Against Omicron Infection Among Quarantined Close Contacts

Liu,

Feng,

Sha

et al. 2023

JAMA Netw Open

View full text Add to dashboard Cite

ImportanceAssessment of additional protection of a booster dose with an inactivated SARS-CoV-2 vaccine is key to developing vaccination strategies for billions of people worldwide who have received the primary 2-dose regimen.ObjectiveTo estimate the relative effectiveness of a booster dose of an inactivated SARS-CoV-2 vaccine against Omicron infection.Design, Setting, and ParticipantsThis cohort study was conducted among primary close contacts without previous SARS-CoV-2 infection identified in Shenzhen, China, between February and October 2022. Multiple strict nucleic acid testing and symptom surveillance for SARS-CoV-2 infection were regularly conducted during the 7-day centralized plus 7-day home-based quarantine.ExposureA booster with an inactivated SARS-CoV-2 vaccine vs no booster after receipt of the primary 2-dose inactivated SARS-CoV-2 vaccine regimen.Main Outcomes and MeasuresThe primary outcomes were overall, symptomatic, and asymptomatic infections. Secondary outcomes were length of incubation and level of cycle threshold values. All the outcomes were assessed during the quarantine period.ResultsAmong 119 438 eligible participants (mean [SD] age, 37.6 [12.0] years; 66 201 men [55.4%]), 86 251 (72.2%) received a booster dose of an inactivated SARS-CoV-2 vaccine and 33 187 (27.8%) did not. A total of 671 cases infected with Omicron BA.2 were confirmed (464 symptomatic and 207 asymptomatic), and no severe infection or death events were observed. At a median (IQR) duration of 111 (75 to 134) days after booster vaccination, the relative effectiveness of a booster was 32.2% (95% CI, 11.3% to 48.2%) for overall infection, 23.8% (95% CI, −8.2% to 46.4%) for symptomatic infection, and 43.3% (95% CI, 12.3% to 63.3%) for asymptomatic infection. The effectiveness against overall infection changed nonlinearly over time following booster vaccination: 44.9% (95% CI, 4.9% to 68.1%) within 60 days, 50.4% (95% CI, 23.7% to 67.7%) at 61 to 120 days, 29.1% (95% CI, −4.8% to 52.1%) at 121 to 180 days, and 19.4% (95% CI, −14.4% to 43.2%) after 180 days (nonlinear P = .03). The effectiveness did not vary significantly according to the interval between booster vaccination and completion of primary vaccination. There was no association of booster vaccination with incubation or cycle threshold values.Conclusions and RelevanceIn this cohort study, a booster dose of an inactivated SARS-CoV-2 vaccine provided additional moderate protection against mild infection for 120 days after receipt, but more research is needed to determine the optimal timing of a booster and its effectiveness in preventing severe infection for a longer duration.

show abstract

“…Hybrid immunity, from COVID-19 vaccination followed by SARS-CoV-2 infection acquired after its Omicron variant began predominating, has been reported to provide greater protection than vaccination alone against subsequent infection over observation periods of up to 3 months. [2][3][4] Our findings indicate that, during more than 1 year of observation, the risk of Omicron variant SARS-CoV2 infection among those with hybrid immunity continued to be significantly less (by three-fold over the entire observation period) than among those with immunity conferred by previous vaccination alone. In addition, this significantly reduced risk persisted despite three progressively more resistant subvariants successively emerging to predominance during the observation period (BA.4 and BA.5 on June 18, 2022, BQ on November 27, 2022, and XBB, on January 29, 2023.…”

Section: Discussionmentioning

confidence: 64%

“…Recent reports indicate people who received COVID-19 vaccination and then acquired SARS-CoV-2 during the first few months after Omicron first predominated (i.e., those with Omicron-era acquired hybrid immunity from both vaccination and Omicron variant infection) have greater protection against subsequent re-infection over observation periods of up to 3 months than those who received vaccination alone. [2][3][4] The durability of protection from such hybrid immunity, however, has not been established. Employees who are healthcare personnel (HCP) working in institutions such as ZSFG that mandate vaccination to work on site and require employees to report any COVID-19-associated symptoms, high-risk exposures, or known positive test results to the institution's occupational health program comprise an ideal group in which to examine the long-term risk of infection associated with COVID-19 hybrid immunity versus that of immunity due to vaccination alone.…”

mentioning

confidence: 99%

Risk of subsequent SARS‐CoV‐2 infection among vaccinated employees with or without hybrid immunity acquired early in the Omicron‐predominant era of the COVID‐19 pandemic

Jacobson,

Blanc,

Tulsky

et al. 2024

American J Industrial Med

View full text Add to dashboard Cite

BackgroundHybrid immunity, from COVID‐19 vaccination followed by SARS‐CoV‐2 infection acquired after its Omicron variant began predominating, has provided greater protection than vaccination alone against subsequent infection over 1–3 months of observation. Its longer‐term protection is unknown.MethodsWe conducted a retrospective cohort study of COVID‐19 case incidence among healthcare personnel (HCP) mandated to be vaccinated and report on COVID‐19‐associated symptoms, high‐risk exposures, or known‐positive test results to an employee health hotline. We compared cases with hybrid immunity, defined as incident COVID‐19 during the first 6 weeks of Omicron‐variant predominance (run‐in period), to those with immunity from vaccination alone during the run‐in period. Time until COVID‐19 infection over 13 subsequent months (observation period) was analyzed by standard survival analysis.ResultsOf 5867 employees, 641 (10.9%, 95% confidence interval [CI]: 10.1%–11.8%) acquired hybrid immunity during the run‐in period. Of these, 104 (16.2%, 95% CI: 13.5%–19.3%) experienced new SARS‐CoV‐2 infection during the 13‐month observation period, compared to 2177 (41.7%, 95% CI: 40.3%–43.0%) of the 5226 HCP without hybrid immunity. Time until incident infection was shorter among the latter (hazard ratio: 3.09, 95% CI: 2.54–3.78).ConclusionsIn a cohort of vaccinated employees, Omicron‐era acquired SARS‐CoV‐2 hybrid immunity was associated with significantly lower risk of subsequent infection over more than a year of observation—a time period far longer than previously reported and during which three, progressively more resistant, Omicron subvariants became predominant. These findings can inform institutional policy and planning for future COVID‐19 additional vaccine dosing requirements for employees, for surveillance programs, and for risk modification efforts.

show abstract

Estimated Effectiveness of Prior SARS-CoV-2 BA.1 or BA.2 Infection and Booster Vaccination Against Omicron BA.5 Subvariant Infection

Abstract: This case-control study estimates the effectiveness of prior SARS-CoV-2 BA.1 or BA.2 infection and booster vaccination against Omicron BA.5 subvariant infection.

Cited by 10 publications

References 6 publications

Pre-infection neutralizing antibodies, Omicron BA.5 breakthrough infection, and long COVID: a propensity score-matched analysis

Pre-infection neutralizing antibodies, Omicron BA.5 breakthrough infection, and long COVID: a propensity score-matched analysis

Inactivated SARS-CoV-2 Vaccine Booster Against Omicron Infection Among Quarantined Close Contacts

Risk of subsequent SARS‐CoV‐2 infection among vaccinated employees with or without hybrid immunity acquired early in the Omicron‐predominant era of the COVID‐19 pandemic

Contact Info

Product

Resources

About