Dose Of Vaccine Research Articles

T Cell Peptide Prediction, Immune Response, and Host-Pathogen Relationship in Vaccinated and Recovered from Mild COVID-19 Subjects.

COVID-19 remains a significant threat, particularly to vulnerable populations. The emergence of new variants necessitates the development of treatments and vaccines that induce both humoral and cellular immunity. This study aimed to identify potentially immunogenic SARS-CoV-2 peptides and to explore the intricate host-pathogen interactions involving peripheral immune responses, memory profiles, and various demographic, clinical, and lifestyle factors. Using in silico and experimental methods, we identified several CD8-restricted SARS-CoV-2 peptides that are either poorly studied or have previously unreported immunogenicity: fifteen from the Spike and three each from non-structural proteins Nsp1-2-3-16. A Spike peptide, LA-9, demonstrated a 57% response rate in ELISpot assays using PBMCs from 14 HLA-A*02:01 positive, vaccinated, and mild-COVID-19 recovered subjects, indicating its potential for diagnostics, research, and multi-epitope vaccine platforms. We also found that younger individuals, with fewer vaccine doses and longer intervals since infection, showed lower anti-Spike (ELISA) and anti-Wuhan neutralizing antibodies (pseudovirus assay), higher naïve T cells, and lower central memory, effector memory, and CD4hiCD8low T cells (flow cytometry) compared to older subjects. In our cohort, a higher prevalence of Vδ2-γδ and DN T cells, and fewer naïve CD8 T cells, seemed to correlate with strong cellular and lower anti-NP antibody responses and to associate with Omicron infection, absence of confusional state, and habitual sporting activity.

COVID-19 Vaccination and Vaccine Hesitancy in the Gaza Strip from a Cross-Sectional Survey in 2023: Prevalence, Risk Factors, and Associations with Health System Interventions.

Preventing COVID-19 in Gaza is crucial due to the devastation of advanced health services infrastructure by war. Despite the high protection offered by COVID-19 vaccines against severe disease, a 2021 survey in Gaza found only half of the population was vaccinated, and one-third was vaccine-hesitant. This follow-up study conducted in March 2023 aimed to re-evaluate vaccination levels, hesitancy, exposure to vaccine promotion efforts, and other risk factors in Gaza. A community-based cross-sectional survey with multistage stratified sampling was used. Associations of primary exposures and other determinants with vaccine status and hesitancy were quantified using bivariate and multivariable logistic regression. In 2023, 63.5% of adults received at least one vaccine dose compared to 49.1% in 2021 (p < 0.001). Vaccine hesitancy prevalence was 31.7% in 2023 versus 34.1% in 2021 (p = 0.395). Adjusted odds of vaccination were 4.2 times higher among those referred by health workers compared to those not referred. Adjusted odds of vaccine hesitancy among those who received information on the vaccine from health workers were 0.3 times that of people who did not receive information. Results suggest health workers could play a crucial role in future vaccination strategies, as their vaccine promotion efforts were linked to better vaccine outcomes. Investing in the skills development of community health workers to contribute to these efforts is recommended.

Comparison of post-COVID-19 pulmonary complications in individuals vaccinated with BioNTech or Sinovac

Aims: Although several research have been undertaken to investigate the impact of the vaccination on long Coronavirus Disease 2019 (COVID-19) syndrome or post-acute sequelae, there is a lack of published evidence on the long-term effects of vaccines on lung-sequelae-related disease. Considering the limited global COVID-19 vaccine distribution, it is essential to establish the impact of vaccination in reducing pulmonary complications. Turkey has been offering COVID-19 vaccines from two platforms, including BNT162b2 (Pfizer-BioNTech, mRNA vaccine) and CoronaVac (Sinovac, inactivated vaccine). This study aimed to evaluate the efficacy of BioNTech and Sinovac vaccines in reducing post-COVID-19 pulmonary complications in individuals. Methods: A total of 94 patients COVID-19 pneumonia patients who were categorized based on the quantity of BioNTech or Sinovac vaccines they received before their first COVID-19 infection were included. The inclusion criteria consisted of a confirmed diagnosis of COVID-19 pneumonia through polymerase chain reaction testing, availability of the mentioned before and follow-up computed tomography scans, and administration of at least one dose of vaccine. Results: The number of complications in patients fully vaccinated with Sinovac and who experienced post-COVID lung complications was significantly greater than in those vaccinated with BioNTech. The C-reactive protein and D-Dimer measurements of individuals who experienced complications in the Sinovac vaccinated group were significantly elevated on the index date. Conclusion: The quantity of lung sequelae after COVID and laboratory parameters indicating this result were found to be higher in inactivated virus vaccines than in mRNA vaccines. This suggests that the protection of inactivated vaccines may be insufficient in severe cases.

Epidemiological and immunological characteristics of middle-aged and elderly people in housing estates after Omicron BA.5 wave in Jinan, China

A great number of COVID-19 patients was caused by Omicron BA.5 subvariant between December 2022 and January 2023 after the end of the zero-COVID-19 policy in China. In this study, we clarified the epidemiological and immunological characteristics of 457 enrolled middle-aged and elderly population in two housing estates after Omicron BA.5 wave. A total of 89.9 % (411/457) individuals have suffered Omicron BA.5 infection, among which 78.1 % (321/411) were symptomatic. The elderly patients were more likely to show fatigue and had longer symptomatic period than that of middle-aged patients post Omicron BA.5 infection. Omicron XBB and BA.2.86 subvariants extensively escaped the immunity elicited by Omicron BA.5 infection. The level of neutralizing antibody was mostly affected by vaccination doses rather than underlying disease status in these participants. It is very important to strengthen the epidemiological investigation and immune resistance assessment among elderly population for control of emerging SARS-CoV-2 variants.

Symptoms Six Weeks After COVID-19 Are Reduced Among US Health Care Personnel Receiving Additional Vaccine Doses During the Omicron Period, December 2021-April 2022.

The objective of this study was to test the hypothesis that subsequent doses of the coronavirus disease 2019 (COVID-19) vaccine are associated with lower incidence of COVID-19-like symptoms at 6 weeks after infection. This study was a case-control analysis of health care personnel in an ongoing multicenter COVID-19 vaccine effectiveness study. We enrolled participants at the time of COVID-19-like symptoms between December 19, 2021, and April 27, 2022, which corresponded to the early Omicron-predominant period after original monovalent severe acute respiratory syndrome coronavirus 2 additional vaccination doses became available. Our outcome was self-reported symptoms completed 6 weeks after the onset of symptoms. We enrolled 2478 participants, of whom 1422 (57%) had COVID-19. The prevalence of symptoms at 6 weeks was 26% (n = 373) in those with COVID-19 and 18% (n = 195) in those without COVID-19. Fatigue (11%) and difficulty sleeping (7%) were most strongly associated with COVID-19. A total of 1643 (66%) participants received a subsequent vaccine dose (after the primary series). Participants with COVID-19 who had received a subsequent vaccination had lower odds of symptoms at 6 weeks (adjusted odds ratio [aOR], 0.55; 95% CI, 0.43-0.70), but this relationship was not observed in those without COVID-19 (aOR, 0.87; 95% CI, 0.59-1.29). Health care personnel who received subsequent doses of original monovalent COVID-19 vaccine had a lower prevalence of symptoms at 6 weeks than those that did not.

Meningococcal Carriage in Children with Atypical Hemolytic Uremic Syndrome Receiving Eculizumab Therapy.

Eculizumab is a first-line treatment for atypical hemolytic uremic syndrome (aHUS), and patients undergoing eculizumab therapy may become more susceptible to infection caused by Neisseria meningitidis (Nm). While meningococcal vaccination is required for patients undergoing eculizumab therapy, there is limited knowledge about meningococcal carriage in children with aHUS. We aimed to evaluate (1) the prevalence of Nm carriage, (2) serogroup distribution, and (3) the immunization status of children undergoing eculizumab treatment for aHUS. The Meningo-aHUS study is a prospective, multi-center study evaluating meningococcal carriage in children and adolescents in Türkiye receiving eculizumab for aHUS. We noted the age, gender, daycare, school, or university attendance, passive smoking status, previous infection and antibiotic use, and previous immunization history, including meningococcal vaccines, from the medical records of those children with aHUS. We collected nasopharyngeal samples, tested them for Nm using real-time polymerase chain reaction, and performed a serogroup analysis on the positive samples. We collected nasopharyngeal samples from 62 children with aHUS. Out of 62 children, 61 (98.4%) had received at least one dose of the meningococcal vaccine. The median time since the last meningococcal vaccine dose was 15 months (1-59 months). We detected meningococcal carriage in three (4.8%, 95% CI 1.0-13.5) children, and all three strains were non-groupable (NG). No other serogroups were detected. Almost all the children received their risk-group meningococcal immunization, including booster doses. A 4.8% of children with aHUS carried NG meningococci and, no vaccine serogroups were detected. Patients treated with eculizumab remain profoundly susceptible to IMD due to these NG meningococcal strains. The occurrence of breakthrough cases and carriage of Nm, especially NG strains, highlights the significance of maintaining a state of constant alertness, promptly seeking medical attention, and swiftly treating any symptoms that align with IMD, regardless of their vaccination status or antibiotic prophylaxis.

Three doses of Sars-CoV-2 mRNA vaccine in older adults result in similar antibody responses but reduced cellular cytokine responses relative to younger adults

ObjectivesBooster COVID-19 vaccinations are used to protect the elderly, a group vulnerable to severe disease. We compared humoral and cellular immunity in older versus younger adults up to eight months after administering a BNT16b2 booster vaccine dose. Next, we analyzed the plasma levels of soluble T cell activation/exhaustion markers. MethodsHome-dwelling older adults (n = 68, median age 86) and younger healthcare workers (n = 35, median age 39), previously vaccinated with two doses of BNT162b2, were given a booster dose at ten months after the initial dose. Our analysis consisted of spike-specific IgG, neutralizing antibodies, memory B cells, IFN-γ and IL-2 secreting T cells and soluble T cell exhaustion/activation markers. ResultsFollowing the initial two doses, the elderly cohort exhibited lower humoral and IFN-γ responses compared to younger adults. The booster dose increased the humoral responses in both older and younger adults. At two months after the booster dose, older and younger vaccinees had comparable levels of antibodies and the responses were maintained up to 18 months. The younger cohort elicited an increase in the cellular response, while no increase was detected in the elderly. The elderly had higher plasma levels of soluble forms of the T cell activation/exhaustion markers CD25 and TIM-3, which inversely correlated with age and T-cell cytokine responses. This suggests that these markers may be related to the observed dysfunctional cellular cytokine response in older adults. However, both elderly and younger adults who experienced breakthrough infections after booster vaccination, elicited more robust humoral and IFN-γ responses. ConclusionsThe booster dose elicited neutralizing and spike-specific antibody responses in the elderly that were comparable with that of the younger cohort. However, the lack of a strong cellular cytokine response to the third dose in the elderly may explain their vulnerability to severe infection and may be a consequence of exhausted or senescent T cell responses. (https://clinicaltrials.gov/study/NCT04706390).

Time-course analysis of antibody and cytokine response after the third SARS-CoV-2 vaccine dose

The widespread administration of an additional dose of the SARS-CoV-2 vaccine has been promoted across adult populations, demonstrating a robust immune response against COVID-19. Longitudinal studies provide crucial data on the durability of immune response after the third vaccination. This study aims to explore the antibody response, neutralizing activity, and cytokine response against the SARS-CoV-2 ancestral strain (wild-type) and its variants during the timeline before and after the administration of the third vaccine dose. Anti-spike antibody titers and neutralizing antibodies blocking ACE2 binding to spike antigens were measured in 62 study participants at baseline, and on days 7, 21, and 180 post-vaccination. Cytokine levels were assessed at the same points except for day 180, with an additional measurement on day 3 post-vaccination. The analysis revealed no substantial variation in anti-spike antibody titer against the SARS-CoV-2 ancestral strain between the pre-vaccination phase and three days following the third dose. However, a significant nine-fold increase in these titers was observed by day 7, maintained until day 21. Although a decrease was observed by day 180, all participants still had detectable antibody levels. A similar trend was noted for neutralizing antibodies, with a four-fold rise by day 7 post-vaccination. At day 180, a diminution of neutralizing antibody titers was evident for both wild-type and all variants, including Omicron subvariant. A transient increase in cytokine activity, notably involving components of the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway, such as CXCL10 and IL-10, was observed within three days after the third dose. This study underscores a distinct amplification of humoral immune response seven days following the third SARS-CoV-2 vaccine dose and observes a decline in neutralizing antibody titers 180 days following the third dose, thus indicating the temporal humoral effectiveness of booster vaccination. A short-term cytokine surge, notably involving the JAK/STAT pathway, highlights the dynamic immune modulation post-vaccination.

Comparison of short- and long-term humoral immune responses to pneumococcal polysaccharide and glycoconjugate vaccines in an HIV-infected population

Immunisation is recommended internationally to protect against pneumococcal infections in HIV-infected adults. However, vaccination schedule designs are mostly based on studies of initial rather than long-term antibody responses. This UK observational study investigated the short- and long-term antibody responses to polysaccharide and glycoconjugate pneumococcal vaccines in an adult HIV-infected cohort. We studied a subgroup of 152 of 839 participants from the AIR (Assessment of Immune Responses to Routine Immunisations in HIV-infected Adults, ISRCTN95588307) studythat had received pneumococcal vaccinationsand had blood samples collected pre- and post-vaccination, as well as at least annually for four subsequent calendar years. Patients received either Pneumovax-23 (PPV, N=89) or Prevenar-13 (PCV, N=63) as their primary vaccine, with immunity assessed by measuring IgG antibody concentrations for 12 pneumococcal polysaccharide serotypes (PnPS). The primary outcome was achieving IgG antibody concentrations above the recommended World Health Organisation (WHO) threshold of 0.35µg/mL for at least 8/12 of the PnPS assessed (WHO≥8/12PnPS). Patients who did not achieve WHO≥8/12PnPS after the primary vaccination were offered further vaccination with PCV; booster vaccinations with PCV were additionally offered to those where antibody levels subsequently fell below the WHO≥8/12PnPS threshold. Patients receiving PCV as their primary pneumococcal vaccine were significantly more likely to achieve WHO≥8/12PnPS after a single vaccine dose than those receiving PPV (54% vs. 33%, p=0.012). This difference persisted following booster vaccination with PCV, with cumulative rates of WHO≥8/12PnPS in those receiving PCV vs. PPV as the primary vaccine of 88% vs. 67% and 100% vs. 85% after receiving up to one and two booster vaccinations, respectively. Where WHO≥8/12PnPS was achieved, this persisted significantly longer in those receiving PCV as their primary vaccine compared to PPV (median: 23.5 vs. 11.1 months; p=0.010). Immunisation with PCV resulted in quantitatively greater antibody responses than immunisation with PPV in a cohort of HIV-infected UK adults. Individuals receiving PCV as their primary vaccine required fewer total pneumococcal vaccine doses to achieve WHO≥8/12PnPS and experienced greater duration of time above this threshold than those with PPV as the primary vaccine. However, the median longevity of both vaccine responses was relatively short, which supports the use of ongoing booster doses using high-valency glycoconjugate vaccines to sustain WHO≥8/12PnPS threshold antibody levels.

Antibody response to SARS-CoV-2 mRNA vaccination in Danish adults exposed to perfluoroalkyl substances (PFASs): The ENFORCE study

IntroductionPer- and polyfluoroalkyl substances (PFASs) have immunotoxic effects in children while studies in adults, including recent studies on the SARS-CoV-2 vaccine response have been less consistent. In a cohort of 50–69-year-olds repeatedly vaccinated against COVID-19 in Denmark from early 2021, we aimed to assess the association between serum-PFAS concentrations and SARS-CoV-2 antibody responses. MethodsWe assessed serum-PFAS concentrations among 371 middle-aged adults from the National Cohort Study of Effectiveness and Safety of SARS-CoV-2 vaccines (ENFORCE) who had received their first vaccination against COVID-19. Following the second dose and the booster (third) Pfizer-BioNTech mRNA vaccination, we measured the specific spike IgG antibody response. Associations between serum-PFAS concentrations at inclusion and spike IgG antibody concentrations after vaccination were assessed using median regression, and analyses were adjusted for age, sex, presence of diabetes, number of vaccines received, and time since vaccination. We further examined the associations between serum-PFAS concentrations at inclusion and changes in spike IgG antibody concentration between the second dose and booster (third) vaccination. ResultsSerum-PFAS concentrations were not associated with spike IgG antibody concentrations after the SARS-CoV-2 vaccinations, but the increase in response after the booster (third) vaccination compared to after the second vaccination was consistently lower at higher serum-PFAS concentrations. Each doubling in the concentration of seven serum-PFASs was associated with a 802 BAU/mL lower median increase in spike IgG antibody response after the booster (third) vaccination (95% CI: −1812; 208) adjusted for confounders. DiscussionAs many adults were probably not immunological naïve prior to vaccination, our results were likely affected by individual variability in immune response to the vaccination. Despite this uncertainty, the diminished increase in SARS-CoV-2 spike antibody response after the booster (third) vaccination at higher PFAS exposure may potentially reflect an immunotoxic impact of the PFASs.

Enhancement of clinical signs in C3H/HeJ mice vaccinated with a highly immunogenic Leptospira methyl-accepting chemotaxis protein following challenge.

Leptospirosis is the most widespread zoonosis and a life-threatening disease in humans and animals. Licensed killed whole-cell vaccines are available for animals; however, they do not offer heterologous protection, do not induce long-term protection, or prevent renal colonization. In this study, we characterized an immunogenic Leptospira methyl-accepting chemotaxis protein (MCP) identified through a reverse vaccinology approach, predicted its structure, and tested the protective efficacy of a recombinant MCP fragment in the C3H/HeJ mice model. The predicted structure of the full-length MCP revealed an architecture typical for topology class I MCPs. A single dose of MCP vaccine elicited a significant IgG antibody response in immunized mice compared to controls (P < 0.0001), especially the IgG1 and IgG2a subclasses. The vaccination with MCP, despite eliciting a robust immune response, did not protect mice from disease and renal colonization. However, survival curves significantly differed between groups, and the MCP-vaccinated group developed clinical signs faster than the control group. There were differences in gross and histopathological changes between the MCP-vaccinated and control groups. The factors leading to enhanced disease process in vaccinated animals need further investigation. We speculate that anti-MCP antibodies may block the MCP signaling cascade and may limit chemotaxis, preventing Leptospira from reaching its destination, but facilitating its maintenance and replication in the blood stream. Such a phenomenon may exist in endemic areas where humans are highly exposed to Leptospira antigens, and the presence of antibodies might lead to disease enhancement. The role of this protein in Leptospira pathogenesis should be further evaluated to comprehend the lack of protection and potential exacerbation of the disease process. The absence of immune correlates of protection from Leptospira infection is still a major limitation of this field and efforts to gather this knowledge are needed.

Stevens–Johnson syndrome in an Asian man after receiving the third dose of COVID-19 vaccine

Stevens–Johnson syndrome in an Asian man after receiving the third dose of COVID-19 vaccine

Abstract B030: Assessing COVID-19 vaccination status and symptoms in persons with a history of cancer

Abstract Background: Persons with a history of cancer are at a higher risk of adverse COVID-19 outcomes due to their immunosuppressed status. Vaccination to COVID-19 has proven effective in decreasing complications from COVID-19 infection. This study explored the vaccination status of persons receiving cancer care (received 1st dose/2nd dose/booster) and their symptoms. Methods: Persons with a cancer diagnosis receiving care at a cancer center clinical site were randomly invited to complete a voluntary survey via email, the EMR, or during an in-person appointment. Paper surveys were completed in the clinic, placed in a sealed collection bin, and collected by research staff weekly. Responses were anonymous. Participants were asked if they had received their 1st/2nd COVID-19 vaccine, their symptoms, and if they had/intended to receive the booster. The study was conducted between September 2021 to September 2022. An EMR review of vaccination uptake was conducted to assess representativeness of our sample. Results: 6,302 persons were invited to complete the survey; 1,733 (28%) responded. 1694 (98%) had received at least one vaccine dose. 67.46% of the participants were white, non-Latinx; 25.39% were Black; 3.17% were Asian. 13.25% were 18-50 years; 30.61% were 50-64;36.81% were 65-74; 19.33% were 75+. 33.13% had a breast cancer diagnosis; 5.47% had lung cancer, 5.41% had prostate cancer, 4.29% had colorectal carcinoma, and 47.42% had other cancers. 1016 (58.63%) received their 1st COVID-19 vaccine, 1437 (82.92%) the 1st/2nd dose, and 1052 (60.70%) had received the booster (3rd dose). Frequently reported symptoms were muscle soreness, pain, fatigue, fever and headache. Those over 65 years were significantly more likely to report fatigue (p&amp;lt;0.001), fever (p&amp;lt;0.0001), headache (p&amp;lt;0.0001), nausea (p=0.0005). Black persons were less likely to report fever (OR: 0.54, 95% CI: 0.34 – 0.86, p=0.0097) and more likely to report pain (OR: 1.58, 95% CI: 1.02 – 2.46, p=0.0427). For persons with breast cancer--29.46% reported muscle soreness, 12.95% reported fatigue, 10.13% reported headache, 9.19% reported fever, 7.13% reported pain. We were unable to stratify by other demographics or cancer type due insufficient sample size. EMR review of vaccination uptake revealed 24.17% had not initiated vaccination. Conclusion: Survey respondents were more likely to have initiated the COVID-19 vaccination process. Older adults were more likely to report fatigue, fever, headache and nausea. Black persons were less likely to report fever and more likely to report pain. Anticipating differences in COVID-19 vaccination symptoms allow for the development of tailored education and resources for self-management and care. Citation Format: Iqra Siddiqui, Ana Maria Lopez, FNU Nikita. Assessing COVID-19 vaccination status and symptoms in persons with a history of cancer [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B030.

SARS-CoV-2 natural infection, but not vaccine-induced immunity, elicits cross-reactive immunity to OC43

BackgroundThe recent SARS-CoV-2 pandemic renewed interest toward other non-severe acute respiratory syndrome human coronaviruses. Among these, OC43 is a seasonal human coronavirus widely diffused in the population (90 % seroprevalence in adults) which is responsible for mild respiratory symptoms. As OC43 protective immunity is short lasting, we investigated whether humoral immunity to SARS-CoV-2, induced by vaccination or spontaneous infection, protects against OC43 re-infection at either systemic or mucosal level. MethodsA neutralization assay was conducted against “wild type" SARS-CoV-2 lineage B.1 (EU) and OC43 in VeroE6 cell lines using plasma and saliva samples from 49 subjects who were never infected and received three BNT162b2 RNA vaccine doses (SARS-CoV-2-vaccinated: SV) and from 25 SARS-CoV-2-infected and vaccinated subjects (SIV). The assays were performed right before (T0), fifteen days (T1) and three months (T2) after the third dose administration (SV) or post-infection (SIV). ResultsAfter the third vaccination dose was administered, SARS-CoV-2-specific neutralizing activity (NA) significantly augmented in SV saliva (p < 0.05) and plasma (p < 0.0001); yet, this NA was not protective against OC43. Conversely, in SIV, at T1, natural infection significantly increased NA against both SARS-CoV-2 (p < 0.01) and OC43 (p < 0.05) at systemic as well as mucosal level; still, this cross-reactivity vanished at T2. Of note, NA against SARS-CoV-2 and OC43 was shown to be higher in SIV compared to SV in plasma and saliva, as well; though, statistically significant differences were evident only in the oral mucosa at T1 (p < 0.05). ConclusionsOur findings show that SARS-CoV-2 spontaneous infection triggers a more comprehensive and cross-reactive immunity than vaccine-induced immunity, protecting against OC43 at the systemic and mucosal levels. These results support the development of a pan-coronavirus vaccine able to prompt cross-reactive immunity even against seasonal coronaviruses, which could have enormous economic and health benefits globally.

Abstract A146: Racial/ethnic differences in the relationship between human papillomavirus vaccination status and up-to-date Papanicolaou tests

Abstract Background: Human papillomavirus (HPV) vaccination and routine Papanicolaou (Pap) testing can prevent morbidity and mortality associated with cervical cancer (CC). Research suggests women who have initiated and completed the HPV vaccine are more likely to have an up-to-date Pap test than women who are unvaccinated against HPV. Limited research has focused on whether the association between HPV vaccination and Pap testing varies based on the number of HPV vaccine doses received across racial/ethnic groups. Methods: We conducted a cross-sectional analysis of 2018 – 2022 Behavioral Risk Factor Surveillance System data to investigate the relationship between HPV vaccination status and having an up-to-date Pap test by race/ethnicity. Based on the Advisory Committee on Immunization Practices’ (ACIP) guidelines, women who received 0 doses of the HPV vaccine were unvaccinated, women who received 1 or 2 doses initiated the vaccine series, and women who received 3 doses completed the HPV vaccine series. Based on the United States Preventive Services Task Force guidelines, women were considered to have an up-to-date Pap test if they reported having one within the past 3 years. We used weighted multivariable logistic regression models to examine the association. Results: Most women (n = 14,615) were unvaccinated (82.9%) and had an up-to- date Pap test (75.5%). Non-Hispanic White (NHW) women had the highest rate of HPV vaccine series completion (11.8%), followed by non-Hispanic Other (NHO) women (11.2%), non- Hispanic Black (NHB) women (8.6%), and Hispanic women (8.3%). NHW women also had the highest rate of up-to-date Pap test (78.8%). NHB women had the second highest rate (77.6%), followed by Hispanic women (67.8%), and NHO women (66.4%). In adjusted analyses, NHO women were 34% less likely to have an up-to-date Pap test than NHW women (OR, 0.66; 95% CI: 0.51-0.86). Compared to unvaccinated women, those who completed and initiated the HPV vaccine series were more likely to have an up-to-date Pap test (initiated: OR: 1.40, 95% CI: 1.04-1.87; completed: OR:1.77, 95% CI: 1.35-2.34). NHB and NHO women who initiated the HPV vaccine series were more likely to have an up-to-date Pap test (NHB: OR: 3.37, 95% CI: 1.65-6.85; NHO: OR: 3.21, 95% CI: 1.73-5.95). NHW women who completed the HPV vaccine series were more likely to have an up-to-date Pap test (OR: 2.19, 95% CI: 1.55-3.08). Conclusion: NHB and NHO women who initiated the HPV vaccine series were three times as likely to have an up-to-date Pap test; NHW women who have completed the HPV vaccine series were twice as likely to receive an up-to-date Pap test. Women who do not receive Pap tests or the HPV vaccine miss important CC prevention opportunities. Thus, relevant stakeholders should aim to improve HPV vaccination rates; doing so could potentially enhance Pap test adherence simultaneously. This may be especially important for NHB and NHO women as they have lower rates of Pap test adherence and HPV vaccine series completion. Citation Format: Elinita Pollard, Meng-Han Tsai, Minjee Lee, Alice W. Lee, Mary A. Gerend. Racial/ethnic differences in the relationship between human papillomavirus vaccination status and up-to-date Papanicolaou tests [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A146.

Persistence of hepatitis B surface antibody until 7 years of age following administration of hexavalent and pentavalent vaccines in children at 2, 4, 6, and 18 months

Thailand incorporated the hepatitis B (HepB) vaccine into the infant combination vaccine known as pentavalent wP-containing vaccines (DTwP-HB-Hib) and hexavalent aP-containing vaccines (DTaP-IPV-HB-Hib). We followed healthy children from the clinical trial (ClinicalTrials.gov NCT02408926) in which children were randomly assigned to receive either pentavalent or hexavalent vaccines for their primary series (administered at 2, 4, and 6 months) and first booster vaccination (at 18 months), following the monovalent HepB vaccine at birth. Blood samples were collected to evaluate the persistence of hepatitis B surface antibody (anti-HBs) at 3, 4, 5, 6 and 7 years of age. The results showed that at 7 years of age, a higher percentage of children in the hexavalent group maintained anti-HBs levels ≥ 10 mIU/mL compared to those in the pentavalent group (86.9 % vs. 59.7 %). This study showed good persistence of anti-HBs among hexavalent-vaccinated children 5.5 years after the last dose of the HepB vaccine.

COVID-19 breakthrough infections in vaccinated individuals at BPKIHS, Nepal

BackgroundAlthough there have been reports of COVID-19 breakthrough infections in vaccinated individuals, the vaccines have demonstrated a high efficacy in preventing severe illness and death. Nepal has reported fewer studies of COVID-19 breakthrough infections. Hence, this study has objective to assess the prevalence, and to describe clinical characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) breakthrough infection.MethodsThis descriptive study was conducted from January to December 2022. The study enrolled 200 individuals who had received the recommended doses of the COVID-19 vaccine and they were RT-PCR positive diagnosed with vaccine breakthrough infections after 14 days of completing the vaccination course. The patient’s demographic and clinical profiles, as well as their outcomes in terms of severity, length of hospital stay, and mortality were recorded.ResultsThe prevalence of SARS-CoV2 infection was 6.3% (547/8682). Among fully vaccinated personnel, the prevalence of breakthrough infections was 6.2% (200/3175). This study found the Omicron variants in respondents. The mean age of the patients was 38.28 years, and 41.5% (83/200) of the breakthrough cases were healthcare workers. The mean time gap between the second dose of vaccination and a positive RT-PCR test was 354.68 days. Of the 200 breakthrough cases, 89% (178) had mild symptoms, 9% (17) had moderate symptoms requiring hospitalization, and 2% (4) were severe cases that required intensive care facility. Among the severe cases, 3 out 4 were above 60 years old. Furthermore, the patients greater than 60 years had longer hospital stays (p < 0.0001) however no deaths were recorded.ConclusionFully vaccinated individuals can experience COVID-19 breakthrough infections and the majority of cases present with mild symptoms. Elderly patients have a higher likelihood of severe disease and longer hospital stay compared to younger patients. The results of this study emphasize the importance of vaccination in mitigating the severity of the disease.

Effectiveness of the First and Second Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine Dose: A Nationwide Cohort Study From Austria on Hybrid Versus Natural Immunity.

We aimed to evaluate the effectiveness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations in previously SARS-CoV-2-infected adults in the general population of Austria during the Delta wave and with extended follow-up. In a nationwide retrospective cohort study, we calculated age-, sex-, and nursing home residency-adjusted Cox proportional hazard ratios (HRs) of coronavirus disease 2019 (COVID-19) deaths, SARS-CoV-2 infections, and non-COVID-19 deaths from 1 October to 31 December 2021, and secondarily with extended follow-up to 30 June 2022. Relative vaccine effectiveness (rVE) is rVE = (1 - HR) × 100. Among 494 646 previously infected adults, 169 543 had received 2 vaccine doses, 133 567 had received 1 dose, and 190 275 were unvaccinated at baseline. We recorded 17 COVID-19 deaths (6 vaccinated, 11 unvaccinated) and 8209 SARS-CoV-2 infections. Absolute risk of COVID-19 deaths was 0.003%. rVE estimates for COVID-19 deaths and reinfections exceeded 75% until the end of 2021 but decreased substantially with extended follow-up. The risk of non-COVID-19 death was lower in those vaccinated versus unvaccinated. First and second SARS-CoV-2 vaccine doses appear effective in the short-term, but with diminishing effectiveness over time. The extremely low COVID-19 mortality, regardless of vaccination, indicates strong protection of previous infection against COVID-19 death. Lower non-COVID-19 mortality in the vaccinated population might suggest a healthy vaccinee bias.

Prevalence and Trends of Not Receiving a Dose of DPT-Containing Vaccine Among Children 12–35 Months: An Analysis of 81 Low- And Middle-Income Countries

AbstractNot receiving a DPT-containing vaccine in early childhood indicates an absence of routine immunization, which puts children at an elevated risk of mortality, morbidity, and worse human development over the life course. We estimated the percentage of children 12–35 months who did not receive a dose of DPT-containing vaccine (termed zero-dose children) using household surveys from 81 low- and middle-income countries conducted between 2014 and 2023. For 68 countries with more than one survey (with the earlier survey conducted 2000–2013), we estimated the average annual percentage point change in prevalence of zero-dose children between the earliest and latest surveys. We also explored the association of zero-dose prevalence with postneonatal and child mortality, health expenditure, and Gavi-eligibility. Overall, 16% of children in our pooled sample had not received a dose of DPT-containing vaccine. There was a 0.8% point decline in zero-dose prevalence per year on average across the period studied. A single percentage point average annual decline in zero-dose prevalence was associated with an average annual decrease of 1.4 deaths in the postneonatal and childhood period per 1000 live births. Gavi-eligible countries had a much faster decline in zero-dose prevalence than other countries. Large gains have been made in reducing the percentage of children who did not receive a DPT-containing vaccine. Efforts to reduce the number of zero-dose children should focus on countries with high prevalence to achieve the Immunization Agenda 2030. Healthcare spending could be prioritized so that the prevalence of zero-dose children is reduced.

Effect of vaccine dose intervals: Considering immunity levels, vaccine efficacy, and strain variants for disease control strategy

In this study, we present an immuno-epidemic model to understand mitigation options during an epidemic break. The model incorporates comorbidity and multiple-vaccine doses through a system of coupled integro-differential equations to analyze the epidemic rate and intensity from a knowledge of the basic reproduction number and time-distributed rate functions. Our modeling results show that the interval between vaccine doses is a key control parameter that can be tuned to significantly influence disease spread. We show that multiple doses induce a hysteresis effect in immunity levels that offers a better mitigation alternative compared to frequent vaccination which is less cost-effective while being more intrusive. Optimal dosing intervals, emphasizing the cost-effectiveness of each vaccination effort, and determined by various factors such as the level of immunity and efficacy of vaccines against different strains, appear to be crucial in disease management. The model is sufficiently generic that can be extended to accommodate specific disease forms.