Prior Vaccination Research Articles

Characterizing healthcare worker attitudes toward the bivalent COVID-19 booster

Background: Recent evidence has shown that the updated COVID-19 bivalent booster is effective in preventing COVID-19 compared with no previous vaccination and prior monovalent vaccination. Despite its effectiveness, uptake has been poor, and a minority of eligible recipients have received the booster. Understanding healthcare worker (HCW) attitudes for and against voluntary uptake of the bivalent booster dose against COVID-19 can help guide communication strategy to maximize uptake. In this survey study, we investigated attitudes toward updated and/or bivalent booster uptake in a behavioral health hospital shortly after a COVID-19 outbreak. Methods: A survey tool was developed and sent to all HCWs at the Yale New Haven Psychiatric Hospital in December 2022. The survey queried demographic data, job category, history of COVID-19, prior COVID-19 vaccinations, perception of COVID-19 exposure, and updated and/or bivalent booster doses. The survey was administered several weeks after a COVID-19 outbreak on multiple inpatient behavioral health units. Receipt of the COVID-19 primary vaccination series and the first booster dose were mandated for HCWs; however, receipt of the bivalent booster was voluntary. Results: The survey was sent to 664 HCWs with primary assignments in behavioral health settings. In total, 182 (27.4%) provided complete responses to the survey and are included in these data. Moreover, 91 HCWs (50.0%) reported previously having COVID-19 at least once. Overall, 100 HCWs (55.0%) received the bivalent booster. The most identified reasons for receiving the bivalent booster were wanting to protect family and friends (n = 113), importance of staying healthy (n = 112), and protecting colleagues and patients (n = 103). The most identified reasons for not wanting to receive the bivalent booster dose were not thinking it provides additional protection (n = 33), “too many” shots already received (n = 31), and concern about side effects (n = 30). Discussion: Bivalent booster dose uptake in HCWs on behavioral health units shortly after a COVID-19 outbreak was greater than the general population. HCWs reported varying reasons for and against receipt of the bivalent booster dose, with the most common being protection of family and friends and perceptions of no additional protection, respectively. A limitation of this study was voluntary response bias, in which results are biased toward individuals more likely to receive a bivalent booster vaccine. It is unclear whether reasons for declining the vaccine are representative of HCWs who did not complete the survey. Assessing attitudes for the bivalent booster dose can assist in guiding communication and outreach strategies to increase vaccine uptake by HCWs.Disclosures: None

Structural changes in the SARS-CoV-2 spike E406W mutant escaping a clinical monoclonal antibody cocktail

Continued evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is eroding antibody responses elicited by prior vaccination and infection. The SARS-CoV-2 receptor-binding domain (RBD) E406W mutation abrogates neutralization mediated by the REGEN-COV therapeutic monoclonal antibody (mAb) COVID-19 cocktail and the AZD1061 (COV2-2130) mAb. Here, we show that this mutation remodels the receptor-binding site allosterically, thereby altering the epitopes recognized by these three mAbs and vaccine-elicited neutralizing antibodies while remaining functional. Our results demonstrate the spectacular structural and functional plasticity of the SARS-CoV-2 RBD, which is continuously evolving in emerging SARS-CoV-2 variants, including currently circulating strains that are accumulating mutations in the antigenic sites remodeled by the E406W substitution.

Prevalence of Antibodies to COVID-19 Due to Infection or Vaccination in US Adults.

-Determine the seroprevalence of SARS-CoV-2 infection and vaccination in a population applying for life insurance. -This is a cross-sectional study of 2584 US life insurance applicants, to determine the seroprevalence of antibodies to COVID-19. This convenience sample was selected on two consecutive days April 25-26, 2022. -For COVID-19, 97.3% are seropositive, and 63.9% have antibodies to nucleocapsid protein, a marker of prior infection. An additional, 33.7% have been vaccinated with no serologic evidence of infection. -Serum and urine samples from a nationwide group of insurance applicants for routine risk assessment were collected. The examination of applicants typically occurs, in their homes, their place of employment, or a clinic. The paramedic exam occurs 7-14 days after the insurance application. Before the exam, an office assistant calls the applicant and inquires if they have been in contact with a person with SARS-CoV-2, been ill within the last 2 weeks, felt sick, or recently had a fever. If the applicant answers yes, the exam is rescheduled. Before sample collection, the applicant reads and signs a consent form to release medical information and testing. Next, the examiner records the applicant's blood pressure, height, and weight. Then, a blood and a urine sample are collected and sent with the consent form to our laboratory via Federal Express. On April 25-26, 2022, we tested 2584 convenience samples from adult insurance applicants for the presence of antibodies to nucleocapsid and spike proteins from SARS-CoV-2. As a standard practice, we reported the client-specified test profile results to our life insurance carriers. In contrast, the COVID-19 test results were only available to the authors. Patient and Public Involvement.-There was no patient involvement in study design, reporting of results, or journal publication selection. There was patient consent to publish de-identified study results. No public involvement occurred in the creation or completion of the study. The authors thank the participants in this study for approving the use of their blood samples to further society's understanding of the SARS-CoV-19 pandemic. Ethics Review.-Western Institutional Review Board reviewed the study design and determined it to be exempt under the Common Rule and applicable guidance. Therefore, it is exempt under 45 CFR § 46.104(d)(4) from using de-identified study samples for epidemiologic investigation, WIRB Work Order #1-1324846-1. In addition, all test subjects had signed a consent allowing research of their blood and urine samples with the removal of personally identifiable information. -The combined seroprevalence for antibodies to nucleocapsid, a marker of prior infection, and antibodies to spike protein, an indicator of either previous infection or vaccination, was 97.3%. Higher infection rates occur in younger vs older age groups, with a non-statistical difference for vaccinated and acquired natural immunity. For the age group 16-84, the total estimated seroprevalence of COVID-19 in the US is 249 million cases. -The US population has widespread immune resistance to current variants of COVID-19 due to prior infection or vaccination. The infectivity of new variants and silent disease, independent of previous infection or vaccination, are the driving force behind the sporadic increase in clinical SARS-CoV-2 cases.

Durability and determinants of anti-SARS-CoV-2 spike antibodies following the second and third doses of mRNA COVID-19 vaccine

ObjectivesTo examine the differences in durability and its determinants of humoral immunity following 2- and 3-dose COVID-19 vaccination. MethodsThroughout the pandemic, we evaluated the anti-spike IgG antibody titers of 2- and 3-dose mRNA vaccine recipients over time among the staff of a medical and research center in Tokyo. Linear mixed models were used to estimate trajectories of antibody titers from 14 to 180 days after the last immune-conferred event (vaccination or infection) and compare antibody waning rates across prior infection and vaccination status, and across background factors in infection-naïve participants. ResultsA total of 6901 measurements from 2964 participants (median age, 35 years; 30% male) were analyzed. Antibody waning rate (percentage per 30 days [95% CI]) was slower after 3 doses (25% [23–26]) than 2 doses (36% [35–37]). Participants with hybrid immunity (vaccination and infection) had further slower waning rates: 2-dose plus infection (16% [9–22]); 3-dose plus infection (21% [17–25]). Older age, male sex, obesity, coexisting diseases, immunosuppressant use, smoking, and alcohol drinking were associated with lower antibody titers, whereas these associations disappeared after 3 doses, except for sex (lower in female participants) and immunosuppressant use. Antibody waned slightly faster in older participants, females, and alcohol drinkers after 2 doses, whereas it did not differ after 3 doses across except sex. DiscussionThe 3-dose mRNA vaccine conferred higher durable antibody titers, and previous infection modestly enhanced its durability. The antibody levels at a given time point and waning speed after 2 doses differed across background factors; however, these differences mostly diminished after 3 doses.

(526) Association of Prior COVID-19 Infection With Newly Diagnosed Erectile Dysfunction: Evaluation of 42,406 COVID-19 Recovered Men

Abstract Introduction The SARS-CoV-2 virus and associated COVID-19 infection is known to cause endothelial cell dysfunction. This has led some to hypothesize that COVID-19 infection may increase the risk of erectile dysfunction. Initial studies evaluating this association have been limited to small, single institution studies or have utilized electronic medical record databases that lack universal follow-up given they only capture follow-up care at a small proportion of health care facilities. Objective To assess if COVID-19 infection recovery is associated with increased rates of newly diagnosed erectile dysfunction (ED) using an insurance claims database. Methods Using IBM MarketScan, a commercial claims database, men with prior COVID-19 infection between January 2020 and January 2021 were identified using ICD-10 diagnosis codes. Using this cohort along with an age-matched cohort of men without prior COVID-19 infection, we assessed the incidence of newly diagnosed erectile dysfunction (ED). Men with ED secondary to prostatectomy or radiation were excluded. Covariates were assessed using a multivariable model to determine association of prior COIVD-19 infection with newly diagnosed ED. Results 42,406 men experienced a COVID-19 infection between January 2020 and January 2021 of which 610 (1.44%) developed new onset ED within 6.5 months follow up. On multivariable analysis while controlling for diabetes, cardiovascular disease, smoking, obesity, hypogonadism, thromboembolism, and GU malignancy, prior COVID-19 infection was associated with increased risk of new onset ED (HR 1.27; 95% CI 1.1-1.5; P=0.001). COVID-19 infection carried a similar association with new onset ED as did diabetes and BMI 25-30, HR 1.3 and 1.29, respectively. Conclusions Prior to the widespread implementation of the COVID-19 vaccine, the incidence of newly diagnosed ED is higher in men with prior COVID-19 infection compared to age-matched controls. Prior COVID-19 infection was associated with a 27% increased likelihood of developing new-onset ED when compared to those without prior infection. Additional longitudinal studies are needed to evaluate the risk of erectile dysfunction after following asymptomatic infection and in the setting prior vaccination. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Cooper Medical, Boston Scientific, Acerus, Coloplast, Endo, Turtle Health, Maximus, FirmTech, StreamDx, Inherent Bioscience.

Community-Acquired Pneumonia Incidence in Adults Aged 18 Years and Older in Goto City, Japan: A Prospective Population-Based Study

Community-Acquired Pneumonia Incidence in Adults Aged 18 Years and Older in Goto City, Japan: A Prospective Population-Based Study

Determinants of influenza and pneumococcal vaccine uptake among preschool children in Singapore.

Young children are at increased risk of severe illness from influenza and pneumococcal infections. The World Health Organization (WHO) recommends vaccination with influenza and pneumococcal conjugate vaccine (PCV). However, in Singapore, vaccine uptake remains suboptimal relative to other routine childhood immunisations. Limited information exists regarding determinants of influenza and pneumococcal vaccine uptake in children. We estimated vaccine uptake and investigated factors associated with influenza and pneumococcal vaccination status by age group using data from a cohort study on acute respiratory infections in children attending preschools in Singapore. We recruited children aged two to six years at 24 participating preschools from June 2017 to July 2018. We determined the proportion of children immunised with influenza vaccine and PCV, and investigated socio-demographic factors associated with vaccine uptake using logistic regression models. Among 505 children, 77.5% were of Chinese ethnicity, and 53.1% were male. History of influenza vaccination was 27.5% of which 11.7% had been vaccinated within the past 12 months. In multivariable analyses, factors associated with influenza vaccine uptake were 'children living in landed property' (aOR = 2.25, 95% CI [1.07-4.67]) and 'history of hospitalisation due to cough' (aOR = 1.85, 95% CI [1.00-3.36]). Nearly three-quarters of participants (70.7% 95%CI: [66.6-74.5]) reported prior PCV vaccination. PCV uptake was higher for younger children. 'Higher parental education' (OR = 2.83, 95% CI [1.51,5.32]), 'household income' (OR = 1.26, 95% CI [1.08,1.48]) and 'smokers in household' (OR = 0.48, 95% CI [0.31,0.74]) were significantly associated with PCV uptake in univariable analyses. Only 'smokers in household' remained significantly associated with PCV uptake (aOR = 0.55, 95% CI [0.33,0.91]) in the adjusted model. Our results indicate that episodes of severe respiratory illness are a cue to influenza vaccination suggesting that doctors are more likely to recommend influenza vaccines to high-risk children. For PCV, our findings suggest overall greater awareness and education on the benefit of PCV vaccination is required.

Omicron (B.1.1.529) BA.1 or BA.2-related effects on immune responses in previously naïve versus imprinted individuals: immune imprinting as an advantage in the humoral immune response against novel variants.

Immune imprinting is a phenomenon in which a person's immune system develops a specific immunological memory of the pathogen or vaccine due to a previous exposure. This memory basically leads to a faster and stronger immune response in a subsequent contact to the same pathogen or vaccine. However, what happens if the pathogen has changed considerably in the meantime due to mutations in the main target region of antibodies, as in the evolution of SARS-CoV-2 from the ancestral strain to B.1.1.529 (Omicron)? In this case, does immune imprinting also confer an advantage in repeated contact and does it lead to a stronger immune response? To clarify these questions, we investigated the effects of immune imprinting in the context of SARS-CoV-2 by comparing a group of previously infection-naïve versus imprinted study participants and determined differences in humoral and cellular immune responses during and after infection with strain SARS-CoV-2 B.1.1.529 BA.1 and BA.2, respectively. We used a commercial CLIA, immunoblots, IFN-γ ELISpots and a plaque-reduction neutralization test to generate a clear and comparable picture of the humoral and cellular immune response in the two study groups. Imprinted participants developed significantly higher antibody titers and showed significantly stronger neutralization capacity against the ancestral strain, BA.1 and BA.5. The immune response of naïve study participants was narrower and related mainly to the receptor-binding domain, which resulted in a lower neutralization capacity against other strains including BA.5. Naïve study participants showed a significantly higher cellular immune response than the imprinted study group, indicating a higher antigenic challenge. The cellular immune response was directed against general structures of SARS-CoV-2 and not specifically against the receptor-binding domain. Viral variant infection elicits variant-specific antibodies and prior mRNA vaccination or infection with a previous SARS-CoV-2 variant imprints serological responses toward the ancestral strain rather than variant antigens. On the other hand, our study shows that the initially higher specific antibody titers due to former imprinting via vaccination or prior infection significantly increased the humoral immune response, and therefore outperformed the humoral immune response of naïve study participants.

Knowledge, attitudes, and practices associated with frequent influenza vaccination among healthcare personnel in Peru, 2016─2018

IntroductionDespite a government-subsidized vaccination program, healthcare personnel (HCP) influenza vaccination uptake remains low in Peru. Using three years of cross-sectional surveys and an additional five years of prior vaccination history of HCP in Peru, we explored HCP knowledge, attitudes, and practices (KAP) of influenza illness and its impact on vaccination frequency. MethodsIn 2016, the Estudio Vacuna de Influenza Peru (VIP) cohort was initiated in Lima, Peru, which collected information about HCP KAP and influenza vaccination history from 2011─2018. HCP were classified by their 8-year influenza vaccination history as never (0 years), infrequently (1─4 years), or frequently (5─8 years) vaccinated. Logistic regression models were used to describe KAP associated with frequent compared to infrequent influenza vaccination, adjusted for each HCP’s healthcare workplace, age, sex, preexisting medical conditions, occupation, and length of time providing direct patient care. ResultsFrom 2016─2018, 5131 HCP were recruited and 3120 fully enrolled in VIP; 2782 consistently reported influenza vaccination status and became our analytic sample. From 2011─2018, 14.3% of HCP never, 61.4% infrequently, and 24.4% frequently received influenza vaccines. Compared to HCP who were infrequently vaccinated, frequently vaccinated HCP were more likely to believe they were susceptible to influenza (adjusted odds ratio [aOR]:1.49, 95% confidence interval [CI]:1.22─1.82), perceived vaccination to be effective (aOR:1.92, 95%CI:1.59─2.32), were knowledgeable about influenza and vaccination (aOR:1.37, 95%CI:1.06─1.77), and believed vaccination had emotional benefits like reduced regret or anger if they became ill with influenza (aOR:1.96, 95%CI:1.60─2.42). HCP who reported vaccination barriers like not having time or a convenient place to receive vaccines had reduced odds of frequent vaccination (aOR:0.74, 95%CI:0.61─0.89) compared to those without reported barriers. ConclusionFew HCP frequently received influenza vaccines during an eight-year period. To increase HCP influenza vaccination in middle-income settings like Peru, campaigns could strengthen influenza risk perception, vaccine knowledge, and accessibility.

Acceptance of COVID-19 Vaccine Among Undergraduate Students

Objective: To assess the acceptance of the COVID-19 vaccine among medical and non-medical undergraduate students and compare the COVID-19 vaccine receptivity differences between medical and non-medical undergraduate students.
 Study Design: Cross-sectional study.
 Place and Duration of Study: Bahria University Medical & Dental College, and Bahria University Karachi Campus Pakistan, from Mar to Jun 2021.
 Methodology: In this study, a total of 392 participants, were selected by non-probability convenience sampling. Students aged 19-26 years were enrolled. Participants were required to sign a voluntary consent form prior to participation. The questionnaire included 21 questions inclusive of demographic characteristics, insight regarding COVID-19 disease, prior EPI vaccine exposure, attitude towards COVID-19 vaccine, including the importance of vaccine to end the pandemic, acceptance of vaccine along with reasons and non-acceptance and sent by email as a Google form to participants.
 Results: There were 171(43.6%) males and females 218(55.6%). The mean age of participants was 20.7±2.29 years. 217(55.4%) students were from the MBBS programs, and 175(44.6%) were from non-MBBS programs. COVID-19 vaccine acceptability was better amongst medical students, with 182(83.9%) considering it safe for use in contrast to 5(2.8%) non-medical students who considered it safe.
 Conclusion: The comparison of knowledge and attitudes towards accepting the COVID-19 vaccine between medical students and non-medical students revealed better acceptance amongst undergraduate medical students than non-medical undergraduate students.

Reasons for allergology consultations prior to COVID-19 vaccination and their outcomes : Two-year experience of an allergy center in North Rhine-Westphalia

To counteract the coronavirus disease 2019 (COVID-19) pandemic, several severe acute respiratory syndrome coronavirus type2 (SARS-CoV-2) vaccines have been licensed since December 2020. Shortly after the start of the vaccination campaigns, occasional allergic reactions related to vaccines were described, thus, leading to concerns in many patients with ahistory of allergies. The aim of this work was to evaluate which anamnestic events represented areason for an allergology work-up before COVID-19 vaccination. Furthermore, the results of the allergology diagnostics are described. We performed aretrospective data analysis of all patients who presented at the Center for Dermatology, Allergology and Dermatosurgery of the Helios University Hospital Wuppertal during the years 2021 and 2022 for allergology work-up prior to COVID-19 vaccination. Demographic data, allergological history, reason for the consultation in the clinic and results of allergology diagnostic tests including reactions after vaccination were included. Atotal of 93patients presented for allergology work-up with COVID-19 vaccines. In about half of the cases, the reasons for the presentation to the clinic were doubts and concerns about allergic reactions and side effects. In all, 26.9% (25/93) of the presented patients had not previously received aCOVID-19 vaccine yet and 23.7% (22/93) of patients developed non-allergic reactions after prior COVID-19 vaccine (e.g., headache, chills, fever, malaise). Of the patients, 46.2% (43/93) were successfully vaccinated in the clinic due to acomplex allergological history, while the remaining 53.8% (50/93) were subjected to outpatient vaccination in the vaccination practice. Only one patient with known chronic spontaneous urticaria developed amild angioedema of the lips afew hours after vaccination; however, we do not consider this episode an allergic reaction to the vaccine due to the time delay. Allergic reactions after COVID-19 vaccines are rare, but many patients with apositive medical history of allergies are concerned about allergic reactions after COVID-19 vaccination. Thus, public work by practicing allergologists is important during vaccination campaigns to meet the concerns and fears of the population, especially of patients with allergies in their medical history.

Prevalence of SARS-CoV-2 Viremia in Presymptomatic Blood Donors in the Delta and Omicron Variant Eras.

Presymptomatic plasma samples from 1596 donors reporting coronavirus disease 2019 infection or symptoms after blood donation were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and anti-S and anti-N antibodies. Prior infection and vaccination both protected from developing SARS-CoV-2 RNAemia and from symptomatic infection. RNAemia rates did not differ in the Delta and Omicron variant eras.

Impact of prior flavivirus vaccination on immunogenicity and efficacy of an inactivated Zika vaccine in Indian rhesus macaques.

Flaviviruses are antigenically related. We evaluated the immunogenicity and efficacy of Takeda's purified inactivated Zika vaccine (PIZV) candidate in macaques previously vaccinated with several commercially available heterologous flavivirus vaccines. Heterologous flavivirus vaccination did not elicit Zika virus (ZIKV) neutralizing antibodies and did not impact neutralizing antibody titers after one dose of PIZV. After a second PIZV dose previous vaccination with flavivirus vaccines had variable impact on ZIKV neutralizing antibody titers. However, all macaques were protected against viremia after Zika virus challenge 8-12months post-PIZV vaccination. Therefore, vaccine-induced immunity against heterologous flavivirus vaccines does not impact PIZV efficacy in macaques.

Duration of influenza vaccine effectiveness in the elderly in Japan: A retrospective cohort study using large-scale population-based registry data.

The immune response to influenza vaccination in the elderly is likely to be lower than that in young adults. Clinical protection may not persist year-round in the elderly. However, the effectiveness of influenza vaccine in the elderly has not been adequately studied, especially in terms of the duration of effectiveness. We used a linked database of healthcare administrative claims data and vaccination records maintained by the municipality of a city in Kanto region of Japan. We studied individuals who were aged 65years or older at baseline and were followed up between April 1, 2014 to March 31, 2020. The duration of influenza vaccine effectiveness by age category was analyzed using a time-dependent piecewise Cox proportional hazard model with time-dependent vaccine status, prior season vaccination and covariates confirmed in the baseline period (age, sex, cancer, diabetes, chronic obstructive pulmonary diseases, asthma, chronic kidney diseases, and cardiovascular diseases). We identified an analysis population of 83,146 individuals, of which 7,401 (8.9%) had experienced influenza and 270 (0.32%) underwent influenza-related hospitalization. Individuals who were vaccinated during the first season (n=47,338) were older than non-vaccinated individuals (n=35,808) (average age, 75.8 vs. 74.1years, respectively). The multivariable analysis showed a lower incidence of influenza in vaccinated individuals (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.43-0.51; P<0.001), while the incidence of hospitalization for influenza did not differ significantly by vaccination status (HR, 0.79; 95% CI, 0.53-1.18; P=0.249). Protective effectiveness against incidence was maintained for 4 or 5months after vaccination in those aged 65-69 and 80-years, 5months in 70-79years. Our study identified moderate vaccine effectiveness in preventing the incidence of influenza in the Japanese elderly. Vaccine effectiveness showed a trend of gradual attenuation. Clinicians should suspect influenza infection even in those vaccinated, especially in elderly individuals who had received vaccination more than 4 or 5months previously.

A Case of Acute Motor Sensory Axonal Neuropathy, a Rare Form of Guillain-Barre Syndrome, Developing After Multiple COVID-19 Infections (P13-8.009)

<h3>Objective:</h3> Guillain-Barre syndrome (GBS), an autoimmune polyneuropathy characterized by ascending weakness and characteristic cerebrospinal fluid (CSF) findings, has been identified in patients previously diagnosed with COVID-19, treated for COVID-19 infection, or vaccinated against the same. GBS is divided into axonal and demyelinating subtypes, and confirmatory testing such as electromyography and nerve conduction studies can help differentiate between subtypes. Here we present a case with recurrent COVID-19 infections, most recently treated with bebtelovimab, who developed acute motor sensory axonal neuropathy (AMSAN), a rare variant of axonal GBS. <h3>Background:</h3> A 33-year-old female presented with progressive ascending weakness and sensory loss that started two weeks after COVID-19 infection. She was fully vaccinated, however, had four episodes of COVID-19 infection within the past year and a half. Two weeks after the most recent infection, which was treated with bebtelovimab, she developed rapidly progressive weakness and sensory impairment in bilateral lower extremities quickly involving upper extremities. She received two rounds of intravenous immunoglobulin (IVIG) three and five weeks after symptoms onset. Her symptoms continued to progress requiring hospitalization. Exam showed severe weakness in all limbs with distal muscle atrophy in upper extremities. Imaging was negative. CSF demostrated albuminocytological dissociation. Nerve conduction studies concluded severe motor and sensory axonal neuropathy with active denervation which led to the suspicion of Acute Motor and Sensory Axonal Neuropathy (AMSAN), a rare variant of GBS. She underwent plasmapheresis with only minimal improvement. <h3>Design/Methods:</h3> N/A <h3>Results:</h3> N/A <h3>Conclusions:</h3> Many cases of GBS have been reported after COVID-19 infection but only a few of them are about AMSAN. This case presents unique features including multiple COVID-19 infections despite prior vaccination, and the development of this rare variant of GBS. It raises the concern of multiple COVID-19 infections having a cumulative impact on peripheral nervous system leading to more severe forms of GBS with poor response to treatment. <b>Disclosure:</b> Dr. Narvaez Caicedo has nothing to disclose. Mr. Rao has nothing to disclose. Dr. Patel has nothing to disclose. Dr. Wu has nothing to disclose.

Peripheral Neuropathy in Long-COVID Patients: Demographic Distribution and Risk Factors (P6-10.001)

<h3>Objective:</h3> To examine the demographic distribution and risk factors in long-COVID patients developing new-onset or progressing peripheral neuropathy (PN). <h3>Background:</h3> Neurologic symptoms following acute-phase COVID are common. Incidence of PN has been shown to be higher in long-COVID patients compared to influenza patients and the general population for reasons not well understood. This is a novel study on the risk factors of both new-onset and progressing long-COVID PN and may guide future studies on etiology and clinical management. <h3>Design/Methods:</h3> Electronic health records of patients who visited a multi-disciplinary post-COVID clinic (PCC) between March 2021 and September 2022 were reviewed. Patients were categorized into four groups: new-onset PN group had new PCC or EMG PN diagnosis following COVID infection; progressing PN group had both new and pre-existing diagnoses relative to infection; non-progressing PN group had pre-existing but no new diagnosis; non-PN group had never received a diagnosis. Demographics, BMI, prior COVID vaccination, chronic comorbidities, and medications were studied. <h3>Results:</h3> Of 639 patients, 21(3.29%) had new-onset PN, 20(3.13%) had progressing PN, and 31(4.85%) had non-progressing PN. Patients with new-onset PN were older (55.5±13.2 vs. 50.3±14.0, p=0.047), more male (47.6% vs 26.1%, p=0.029), and more likely been hospitalized for COVID (47.6% vs 22.4%, p=0.007) compared with non-PN patients. Patients with progressing PN were older (65.5±9.2 vs 50.3±14.0, p&lt;0.001), more likely to have diabetes (35.0% vs 15.0%, p=0.016) and hypertension (70.0% vs 34.3%, p&lt;0.001) and take some form of diabetes medication (30.0% vs 14.1%, p=0.048) and hypertension medication (65.0% vs 39.0%, p=0.019) compared to patients with no PN. Patients with progressing PN were older (65.5±9.14 vs 57.0±11.85, p=0.050) than non-progressing PN patients. <h3>Conclusions:</h3> Older age was associated with new-onset and progressing PN in long-COVID patients. This and other associated findings provide further opportunities to study possible contribution of immunological, metabolic, and degenerative factors to long-COVID neurologic symptoms. <b>Disclosure:</b> Mr. Li has nothing to disclose. Mr. Bohn has nothing to disclose. Mr. Todd has nothing to disclose. Ms. A Pater has nothing to disclose. Ms. Carroll has nothing to disclose. Dr. Henriksen has nothing to disclose. Dr. Chang has nothing to disclose.

Effectiveness of the Coronavirus Disease 2019 Bivalent Vaccine.

The purpose of this study was to evaluate whether a bivalent coronavirus disease 2019 (COVID-19) vaccine protects against COVID-19. The study included employees of Cleveland Clinic in employment when the bivalent COVID-19 vaccine first became available. Cumulative incidence of COVID-19 over the following 26 weeks was examined. Protection provided by vaccination (analyzed as a time-dependent covariate) was evaluated using Cox proportional hazards regression, with change in dominant circulating lineages over time accounted for by time-dependent coefficients. The analysis was adjusted for the pandemic phase when the last prior COVID-19 episode occurred and the number of prior vaccine doses. Among 51 017 employees, COVID-19 occurred in 4424 (8.7%) during the study. In multivariable analysis, the bivalent-vaccinated state was associated with lower risk of COVID-19 during the BA.4/5-dominant (hazard ratio, 0.71 [95% confidence interval, .63-79]) and the BQ-dominant (0.80 [.69-.94]) phases, but decreased risk was not found during the XBB-dominant phase (0.96 [.82-.1.12]). The estimated vaccine effectiveness was 29% (95% confidence interval, 21%-37%), 20% (6%-31%), and 4% (-12% to 18%), during the BA.4/5-, BQ-, and XBB-dominant phases, respectively. The risk of COVID-19 also increased with time since the most recent prior COVID-19 episode and with the number of vaccine doses previously received. The bivalent COVID-19 vaccine given to working-aged adults afforded modest protection overall against COVID-19 while the BA.4/5 lineages were the dominant circulating strains, afforded less protection when the BQ lineages were dominant, and effectiveness was not demonstrated when the XBB lineages were dominant.

Influenza vaccine uptake among children and older adults in China: a secondary analysis of a quasi-experimental study

BackgroundInfluenza vaccination is the key to prevent influenza-related disease, especially among high-risk populations. However, influenza vaccine uptake in China is low. This secondary analysis of a quasi-experimental trial aimed to understand factors associated with influenza vaccine uptake among children and older people stratified by funding context.MethodsA total of 225 children (aged 0.5-8 years) and 225 older people (aged 60 years or above) were recruited from three clinics (rural, suburban and urban) in Guangdong Province. Participants were allocated into two groups based on funding contexts: a self-paid group (N = 150, 75 children and 75 older adults) in which participants paid full price for their vaccination; and a subsidized group (N = 300, 150 children and 150 older adults) in which varying levels of financial support was provided. Univariate and multivariable logistic regressions were conducted stratified by funding contexts.ResultsOverall, 75.0% (225/300) of participants in the subsidized group and 36.7% (55/150) in the self-paid group got vaccinated. Older adults had lower vaccination rates than children in both funding groups, while both age groups showed much higher uptake in the subsidized group than in the self-paid group (aOR = 5.96, 95% CI: 3.77–9.42, p = 0.001). In the self-paid group, having prior influenza vaccination history of children (aOR:2.61, 95%CI: 1.06–6.42) or older people (aOR:4.76, 95%CI: 1.08–20.90) was associated with increased influenza vaccine uptake compared to those who had no prior vaccination experiences in the family. While in the subsidized group, participants who got married or lived with partners (aOR = 0.32, 0.10–0.98) had lower vaccination uptake than single ones. Trust in providers’ advice (aOR = 4.95, 95%CI:1.99, 12.43), perceived effectiveness of the vaccine (aOR: 12.18, 95%CI: 5.21–28.50), and experienced influenza-like illnesses in the family in the past year (aOR = 46.52, 4.10, 533.78) were associated with higher vaccine uptake.ConclusionsOlder people had suboptimal vaccine uptake compared to children in both contexts and need more attention to enhance influenza vaccination. Tailoring interventions to different vaccine funding contexts may help improve influenza vaccination: In self-paid context, motivating people to accept their first ever influenza vaccination may be a promising strategy. In subsidized context, improving public confidence in vaccine effectiveness and providers’ advice would be useful.

BCG Vaccination and the Risk of Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis.

(1) Background: Type 1 diabetes mellitus (T1D) is an autoimmune disease characterized by progressive and irreversible autoimmune destruction of pancreatic beta cell islets, resulting in absolute insulin deficiency. To date, several epidemiologic and observational studies have evaluated the possible impact of BCG vaccination on T1D development, but the results are controversial. To elucidate this issue, we aimed to conduct a systematic review and meta-analysis of published cohort studies in this field. (2) Methods: A systematic search was performed for relevant studies published up to 20 September 2022 using Pubmed/Medline, Embase, and Scopus. Cohort studies, containing original information about the association between T1D and BCG vaccination, were included for further analysis. Pooled estimates and 95% confidence intervals (CI) for the risk ratio of T1D in BCG-vaccinated individuals compared to unvaccinated ones were assessed using the fixed effect model. (3) Results: Out of 630 potentially relevant articles, five cohort studies met the inclusion criteria. The total population of all included studies was 864,582. The overall pooled risk ratio of T1D development in BCG vaccinated and unvaccinated individuals was found to be 1.018 (95% CI 0.908-1.141, I2: 0%). (4) Conclusions: Our study revealed no protective or facilitative effect of prior BCG vaccination in T1D development.

An Observational Study on Patients With COVID-19 Infection Admitted to the Intensive Care Unit With Respect to Their Vaccination Status.

Background SARS-CoV-2 (COVID-19) created unprecedented recurrent waves of pandemic globally. Apart from COVID-19-appropriate behavior, vaccinating the population was proposed to be the most effective measure to control these outbreaks. However, the outcomes of vaccinated patients admitted to the intensive care unit (ICU) and their comparison with unvaccinated counterparts, especially in developing countries, have not been extensively studied. Materials and methods Our study examined consecutive patients with positive RT-PCR for COVID-19 admitted to the ICU from August 1, 2021, to July 31, 2022. Prior vaccination status and its relation to demographics, disease severity, mortality, and length of stay were analyzed. Results Among 436 patients admitted to the ICU, 76 (15.4%) were unvaccinated and 369 (84.6%) were vaccinated against COVID-19. Vaccinated patients were significantly older and hypertensive, and had comparatively less severity of illness than unvaccinated patients. Crude ICU and hospital mortality were significantly lower among vaccinated patients than unvaccinated patients (15.2% versus 25.4% and 16% versus 22.3%, respectively; P<0.05). Furthermore, risk-adjusted multivariate analysis demonstrated a strong but statistically nonsignificant inverse association between vaccination status and ICU mortality (odds ratio (OR)=0.540, 95% confidence interval (CI)=0.290-1.006, P=0.052). Conclusion In severe COVID-19-infected patients who required admission to the ICU, the majority were vaccinated. However, the severity of illness and hospital mortality was significantly lower among vaccinated patients with breakthrough infections.