Patients receiving anti-CD20 antibodies showed limited efficacy of a booster dose of BNT162b2. Patients with lymphomas combine such immunotherapies with cytotoxic chemotherapies that could result in an even greater alteration of the immune response to vaccination. We report here the impact of a third vaccine dose on T cell specific responses in a small cohort of patients treated in our center by anti-CD20 therapies and cytotoxic chemotherapies for lymphoid malignancies. Our results showed that a third dose in these severely immune suppressed patients could improve the expansion on CD4+Th1+T cell responses while the effect CD8 + T cell responses was marginal.

BACKGROUND: Respiratory syncytial virus (RSV) imposes a substantial burden on pediatric hospital capacity in Europe. Promising prophylactic interventions against RSV including monoclonal antibodies (mAb) and maternal immunizations (MI) are close to licensure. Therefore, we aimed to evaluate the cost-effectiveness of potential mAb and MI interventions against RSV in infants, for six European countries. METHODS: We used a static cohort model to compare costs and health effects of four intervention programs to no program and to each other: year-round MI, year-round mAb, seasonal mAb (October to April), and seasonal mAb plus a catch-up program in October. Input parameters were obtained from national registries and literature. Influential input parameters were identified with the expected value of partial perfect information and extensive scenario analyses (including the impact of interventions on wheezing and asthma). RESULTS: From the health care payer perspective, and at a price of €50 per dose (mAb and MI), seasonal mAb plus catch-up was cost-saving in Scotland, and cost-effective for willingness-to-pay (WTP) values ≥€20,000 (England, Finland) or €30,000 (Denmark) per quality adjusted life-year (QALY) gained for all scenarios considered, except when using ICD-10 based hospitalization data. For the Netherlands, seasonal mAb was preferred (WTP value: €30,000-€90,000) for most scenarios. For Veneto region (Italy), either seasonal mAb with or without catch-up or MI was preferred, depending on the scenario and WTP value. From a full societal perspective (including leisure time lost), the seasonal mAb plus catch-up program was cost-saving for all countries except the Netherlands. CONCLUSION: The choice between a MI or mAb program depends on the level and duration of protection, price, availability, and feasibility of such programs, which should be based on the latest available evidence. Future research should focus on measuring accurately age-specific RSV-attributable hospitalizations in very young children.

In the development of new vaccines, many trials use age de-escalation: after establishing safety and efficacy in adult populations, progressively younger cohorts are enrolled and studied. Age de-escalation promotes many values. The responsibility to protect children from potential risks of experimental vaccines is significant, not only given increased risks of adverse effects but also because parents and medical professionals have a moral responsibility to protect children from harms associated with novel, uncertain interventions. Further, given that young children cannot provide informed consent, acceptable risks for research requiring proxy consent are lower than for adults making decisions for themselves. Although age de-escalation approaches are widely used in vaccine trials, including notably in the recent development of pediatric COVID-19 vaccines, ethicists have not addressed the benefits and risks of these approaches. Their benefits are largely assumed and unstated, while their potential risks are usually overlooked. There are no official ethics guidelines for the use of age de-escalation in clinical research. In this paper, we provide a systematic account of key moral factors to consider when employing age de-escalation. Analyzing pediatric COVID-19 vaccine development as our key case study, we clarify the benefits, risks, and trade-offs involved in age de-escalation approaches and call for the development of evidence-based best practice guidelines to identify when age de-escalation is likely to be an ethical strategy in vaccine development.

Vero cell culture-derived Japanese encephalitis (JE) vaccine (JE-VC; Ixiaro) was approved in the United States in 2009. The previous JE vaccine, an inactivated mouse brain-derived vaccine, had been associated with rare, but serious, allergic and neurologic adverse events (AE). Studies and AE surveillance have supported JE-VC's safety, but one evaluation among military personnel found elevated hypersensitivity and neurologic AE rates. However, co-administration of multiple vaccines to some personnel might have affected results. We retrospectively compared rates of hypersensitivity and neurologic AEs within 28 days following vaccination of military personnel with JE-VC or parenteral Vi capsular polysaccharide typhoid vaccine administered without other vaccines from July 1, 2011, through August 31, 2019. Rates of most events were similar between the vaccines. Only delayed hypersensitivity reactions occurred more frequently following JE-VC (rate ratio: 4.2, 95 % CI 1.2-15.3; p = 0.03), but rates were low for both vaccines. These results support JE-VC's safety.

BACKGROUND: We aimed to evaluate the feasibility of implementing an emergency department (ED)-based Coronavirus Disease of 2019 (COVID-19) vaccination protocol in a population of unhoused patients. METHODS: On June 10, 2021, a best practice alert (BPA) was implemented that fired when an ED provider opened the charts of unhoused patients and prompted the provider to order COVID-19 vaccination for eligible patients. We downloaded electronic medical record data of patients who received a COVID-19 vaccine in the ED between June 10, 2021 and August 26, 2021. The outcomes of interest were the number of unhoused, and the total number of patients vaccinated for COVID-19 during the study period. Data were described with simple descriptive statistics. RESULTS: There were 25,871 patient encounters in 19,992 unique patients (mean 1.3 visits/patient) in the emergency department during the study period. There were 1,474 (6% of total ED population) visits in 1,085 unique patients who were unhoused (mean 1.4 visits/patient). The BPA fired in 1,046 unhoused patient encounters (71% of PEH encounters) and was accepted in 79 (8%). Forty-three unhoused patients were vaccinated as a result of the BPA (4% of BPA fires) and 18 unhoused patients were vaccinated without BPA prompting. An additional 76 domiciled patients were vaccinated in the ED. CONCLUSIONS: Implementing an ED-based COVID-19 vaccination program is feasible, however, only a small number of patients underwent COVID-19 vaccination. Further studies are needed to explore the utility of using the ED as a setting for COVID-19 vaccination.

BACKGROUND: Since 2012, reports of primary ovarian insufficiency (POI) temporally associated with receipt of human papillomavirus (HPV) vaccine have been published leading to questions about a potential causal association. A Vaccine Safety Datalink study did not find an increased risk for POI after vaccination. We reviewed the Vaccine Adverse Event Reporting System (VAERS) to describe POI reports. METHODS: We searched VAERS, a U.S. passive surveillance system, for domestic POI reports received from 01/01/1990 to 12/31/2017 after any vaccination. The search used both Medical Dictionary for Regulatory Activity Preferred Terms and a text-based search for POI and its symptoms. All reports were reviewed, and the American College of Obstetricians and Gynecologists (ACOG) guidelines for POI diagnosis were applied. Data mining for disproportionate reporting was conducted. RESULTS: Six hundred fifty-two reports met the search criteria and clinical review identified 19 POI reports. Most reports (n = 16) were received between 2013 and 2017. The median age at vaccination was 14.5 years (range 10-25 years) and the median interval between first dose of vaccination and reporting the event to VAERS was 43 months (range 4-132 months; mean 59.6 months). Four reports met ACOG diagnostic criteria; one with an underlying cause (47XXX chromosomal abnormality) reported. Eleven reports documented menstrual irregularity ≥ 3 months; 5 had ≥ 1 laboratory test result used to diagnose POI. Eighteen of 19 reports described receipt of HPV vaccine with or without other vaccines. Other vaccines reported were meningococcal conjugate vaccine, hepatitis A, varicella and tetanus toxoid, reduced diphtheria toxoid and acellular pertussis. Disproportionate reporting was found for three relevant coding terms after HPV vaccination. CONCLUSIONS: POI is rarely reported to VAERS. Most reports contained limited diagnostic information and were submitted after published cases of POI following HPV vaccination. Results of our review do not suggest a safety concern.

Brucellosis, a worldwide zoonotic disease, is endemic in many developing countries. Besides causing significant economic losses for the livestock industry, it has severe consequences for human health. In endemic regions, small ruminants infected by Brucella melitensis are the main source of human brucellosis. Rev1, the only vaccine currently recommended to control the disease in sheep and goats, has several drawbacks. Rough lipopolysaccharide (R-LPS) mutants have been tested as alternatives, but most lack efficacy. Those in the Wzm/Wzt system responsible for O-polysaccharide export to the periplasm have been proposed as promising vaccine candidates, although to date they have been scarcely investigated in the natural host. In the present work, we studied the biological properties of a 16MΔwzm in-frame deletion mutant, including its safety in pregnant mice and sheep. In mice, 16MΔwzm prevented placental and fetal infections before parturition and protected against B. melitensis and Brucella ovis infections. In sheep, 16MΔwzm was equally safe in lambs, rams, and non-pregnant ewes, inducing some transient Rose Bengal reactions (<7 weeks). The serological reactions occurred earlier and more strongly in pregnant than in non-pregnant ewes and were significantly reduced when conjunctival rather than subcutaneous vaccination was used. In ewes vaccinated at mid-pregnancy, 16MΔwzm was not shed in vaginal discharges during the pregnancy and did not induce abortions/stillbirths. However, some ewes showed a transitory reactivation of infection in placentas and/or milk at parturition, accompanied by a seroconversion in smooth LPS (S-LPS) and/or R-LPS tests. Overall, 16MΔwzm can be considered as a safe vaccine for lambs, rams, and non-pregnant ewes, but its use at mid-pregnancy should be avoided to prevent vaccine dissemination at parturition. If the efficacy results against B. melitensis and B. ovis observed in mice are confirmed by further studies in the natural host, 16MΔwzm could constitute a useful vaccine.

Dengue is the most prevalent mosquito-borne viral disease and continues to be a global public health concern. Although a licensed dengue vaccine is available, its efficacy and safety profile are not satisfactory. Hence, there remains a need for a safe and effective dengue vaccine. We are currently developing a bivalent dengue vaccine candidate. This vaccine candidate is composed of a C-terminus truncated non-structural protein 1 (NS11-279) and envelope domain III (EDIII) of DENV-2 encapsidated in the nanocarriers, N, N, N-trimethyl chitosan nanoparticles (TMC NPs). The immunogenicity of this bivalent vaccine candidate was investigated in the present study using BALB/c mice. In this work, we demonstrate that NS1 + EDIII TMC NP-immunized mice strongly elicited antigen-specific antibody responses (anti-NS1 and anti-EDIII IgG) and T-cell responses (NS1- and EDIII-specific-CD4+ and CD8+ T cells). Importantly, the antibody response induced by NS1 + EDIII TMC NPs provided antiviral activities against DENV-2, including serotype-specific neutralization and antibody-mediated complement-dependent cytotoxicity. Moreover, the significant upregulation of Th1- and Th2-associated cytokines, as well as the increased levels of antigen-specific IgG2a and IgG1, indicated a balanced Th1/Th2 response. Collectively, our findings suggest that NS1 + EDIII TMC NPs induced protective responses that can not only neutralize infectious DENV-2 but also eliminate DENV-2-infected cells.

OBJECTIVE: To evaluate the relationship between the change of titer and adverse events after the third vaccination for COVID-19 among healthcare workers. DESIGN AND SETTING: This was a prospective cohort study, and the follow-up period was from December 2021 to November 2023. PARTICIPANTS: A total of 392 healthcare workers aged over 20 years who worked at the facility and wished to have vaccine antibody titers measured participated in this study. EXPOSURES: A third dose of BNT162b2 COVID-19 vaccine was administered to healthcare workers working at the hospital, and we evaluated the changes in antibody titers before and after the vaccine, as well as adverse reactions after vaccination. MAIN OUTCOMES AND MEASURES: The primary endpoints were adverse reactions within 7 days after the third dose of COVID-19 vaccine and the rate of increase in COVID-19 vaccine antibody titer at 4 weeks. RESULTS: A total of 392 people participated in the study, of whom 358 participants had their antibody titers measured before and after the booster vaccination. The overall IgG geometric mean was 609 U/mL (561-663) before booster vaccination and increased to 18,735 U/mL (17,509-20,049) at 4 weeks after vaccination (p < 0.001). Multivariate analysis showed no statistically significant relationship between the primary endpoints, such as a change in antibody titer due to the presence of fever after vaccination or a change in antibody titer due to swelling at the vaccination site. Factors affecting the rate of increase in antibody titer, evaluated as secondary endpoints, were suggested to be age (1.02 (95 % confidence interval (CI): 1.01-1.03)) and hypertension (0.66 (95 % CI: 0.47-0.93)). CONCLUSIONS AND RELEVANCE: In relation to the booster effect of the third dose of COVID-19 vaccination, there was no statistically significant difference in the presence of fever or use of antipyretic or other drugs.

Longitudinal data on the immune response from the first dose to several months after the third dose of COVID-19 vaccine are limited. We analyzed the immune response in 406 Japanese healthcare workers who received at least three doses of vaccine. The geometric mean anti-receptor binding domain IgG antibody titers and antigen-stimulated T-cell interferon-gamma levels after 6 months after receiving a third dose were similar to those 8 weeks after receiving a second dose. Humoral and cellular immunity induced by the third dose was more durable than that induced by the second dose. UMIN Clinical Trials Registry ID: UMIN000043340.

BACKGROUND: This study evaluated safety, reactogenicity, and immunogenicity of a 2-month homologous booster regimen of Ad26.COV2.S in Japanese adults. METHODS: In this multicenter, placebo-controlled, Phase 1 trial, adults (Cohort 1, aged 20-55 years, N = 125; Cohort 2, aged ≥ 65 years, N = 125) were randomized 2:2:1 to receive Ad26.COV2.S 5 × 1010 viral particles (vp), Ad26.COV2.S 1 × 1011 vp, or placebo, followed by a homologous booster 56 days later. Safety, reactogenicity, and immunogenicity were assessed. RESULTS: Two hundred participants received Ad26.COV2.S and 50 received placebo. The most frequent solicited local adverse event (AE) was vaccination-site pain, and the most frequent solicited systemic AEs were fatigue, myalgia, and headache. After primary vaccination, neutralizing and binding antibody levels increased through Day 57 (post-prime) in both cohorts. Fourteen days after boosting (Day 71), neutralizing antibody geometric mean titers (GMTs) had almost reached their peak value in Cohort 1 (5 × 1010 vp: GMT = 1049; 1 × 1011 vp: GMT = 1470) and peaked in Cohort 2 (504; 651); at Day 85, GMTs had declined minimally in Cohort 2. For both cohorts, binding antibody levels peaked at Day 71 with minimal decline at Day 85. CONCLUSION: A single dose and homologous Ad26.COV2.S booster increased antibody responses with an acceptable safety profile in Japanese adults (ClinicalTrials.gov Identifier: NCT04509947).

Large quantities of antigens are required since protective antigens, such as classical swine fever virus (CSFV) E2 protein, are widely used in diagnostic reagents and subunit vaccines. Compared to clonal cell lines and transient gene expression, stable cell pools provide a potential alternative platform to rapidly produce large amounts of antigens. In this work, firstly, Human embryonic kidney 293 T (HEK293T) cell pools expressing E2 protein were developed by transduction of lentiviral vectors. On the one hand, the SP7 was selected from 7 well-performing signal peptides to remarkably increase the production of E2 protein. On the other hand, it was found that high MOI could improve the expression of E2 protein by increasing gene copy numbers. Moreover, the HEK293T cell pools were evaluated for stability by passages and batch cultures, demonstrating that the cell pools were stable for at least 90 days. And then, the performance of the cell pools in batch, fed-batch, and semi-perfusion was studied. Among them, the titer of E2 protein was up to 2 g/L in semi-perfusion, which is currently the highest to the authors' knowledge. Finally, the aggregations and immunogenicity of the E2 protein were analyzed by SDS-PAGE and immunization of mice, respectively. There was no significant difference in aggregations and antibody titers of E2 protein in three culture methods. These results suggest that stable HEK293T cell pools are a promising and robust platform for rapid and efficient production of recombinant proteins.

Immunizations for influenza and pneumococcus are effective interventions in reducing morbidity and mortality. The objective of this study was to describe the vaccination rates in volunteers from three regions of Argentina during the COVID-19 pandemic. In 2020, 3853 adults were surveyed, 61.6 % were females, 45 % were aged between 40 and 60 and 18.6 % were > 60 years old. The commonest comorbidities were hypertension (12.9 %), dyslipidemia (8.5 %), and smokers or former smokers (9.2 %). The global influenza vaccination rate was 37.7 %, pneumococcal vaccination 24.7 %, and both 17.8 %. Multivariable regression showed that the vaccination rate increased with age and the presence of comorbidities. However, in the subgroup with indications for both vaccines, 71.7 % had the influenza vaccine, 59 % had the pneumococcal vaccine, and 28.3 % received neither. Our study suggests that influenza and pneumococcal vaccine percentages in high-risk patients in Argentina remain sub-optimal. Immunizations with proven reductions in morbimortality could have also been relegated during the COVID pandemic.

A key aspect to vaccine efficacy is formulation stability. Biochemical evaluations provide information on optimal compositions or thermal stability but are routinely validated by ex vivo analysis and not efficacy in animal models. Here we assessed formulations identified to improve or reduce stability of the mucosal adjuvant dmLT being investigated in polio and enterotoxigenic E. coli (ETEC) clinical vaccines. We observed biochemical changes to dmLT protein with formulation or thermal stress, including aggregation or subunit dissociation or alternatively resistance against these changes with specific buffer compositions. However, upon injection or mucosal vaccination with ETEC fimbriae adhesin proteins or inactivated polio virus, experimental findings indicated immunization route and co-administered antigen impacted vaccine immunogenicity more so than dmLT formulation stability (or instability). These results indicate the importance of both biochemical and vaccine-derived immunity assessment in formulation optimization. In addition, these studies have implications for use of dmLT in clinical settings and for delivery in resource poor settings.

BACKGROUND: The public's willingness to get vaccinated continues to be a source of concern. In this study we assessed the psychometric properties of the COVID-19 vaccine hesitancy scale (C19-VHS) as well as the association between the scale and self-reported past COVID-19 vaccination, approximately two weeks after the national vaccine distribution plan was launched in Israel. METHODS: Participants were recruited via an online survey distributed through social media platforms and mailing lists. A total of 650 individuals completed the C19-VHS, the general vaccine hesitancy scale, and the fear of COVID-19 scale, and reported on demographic and pandemic-related characteristics. Principal component and Cronbach's alpha analyses were performed to assess the factor structure and reliability of the scale. Logistic regressions were employed to assess the scale's convergent and discriminative validity. RESULTS: Two factors pertaining to "lack of confidence" (Factor 1) and "risk perception" (Factor 2) emerged. Cronbach's alpha indicated good reliability of Factor 1 (0.93), with lower reliability of Factor 2 (0.72). Younger age was associated with higher risk perception, with women showing less confidence and perceiving greater risks. Lower hesitancy significantly predicted actual COVID-19 vaccine uptake after adjusting for demographic and pandemic-related factors (OR = 1.16, 95%CI 1.11-1.21, p <.001). Older age, being a woman, and receiving the flu vaccine in the past year were also predictive of COVID-19 vaccine uptake. DISCUSSION: The C19-VHS measure shows robust psychometric properties and is associated with actual vaccine uptake. Future studies assessing COVID-19 vaccination attitudes may utilize this scale to assess current COVID-19 vaccine hesitancy in different contexts and cultures.

BACKGROUND: The World Health Organization (WHO) recommended widespread use of the RTS,S/AS01 (RTS,S) malaria vaccine among children residing in regions of moderate to high malaria transmission. This recommendation is informed by RTS,S evidence, including findings from the pilot rollout of the vaccine in Ghana, Kenya, and Malawi. This study estimates the incremental costs of introducing and delivering the malaria vaccine within routine immunization programs in the context of malaria vaccine pilot introduction, to help inform decision-making. METHODS: An activity-based, retrospective costing was conducted from the governments' perspective. Vaccine introduction and delivery costs supported by the donors during the pilot introduction were attributed as costs to the governments under routine implementation. Detailed resource use data were extracted from the pilot program expenditure and activity reports for 2019-2021. Primary data from representative health facilities were collected to inform recurrent operational and service delivery costs.Costs were categorized as introduction or recurrent costs. Both financial and economic costs were estimated and reported in 2020 USD. The cost of donated vaccine doses was evaluated at $2, $5 and $10 per dose and included in the economic cost estimates. Financial costs include the procurement add on costs for the donated vaccines and immunization supplies, along with other direct expenses. FINDINGS: At a vaccine price of $5 per dose, the incremental cost per dose administered across countries ranges from $2.30 to $3.01 (financial), and $8.28 to $10.29 (economic). The non-vaccine cost of delivery ranges between $1.04 and $2.46 (financial) and $1.52 and $4.62 (economic), by country. Considering only recurrent costs, the non-vaccine cost of delivery per dose ranges between $0.29 and $0.89 (financial) and $0.59 and $2.29 (economic), by country. Introduction costs constitute between 33% and 71% of total financial costs. Commodity and procurement add-on costs are the main cost drivers of total cost across countries. Incremental resource needs for implementation are dependent on country's baseline immunization program capacity constraints. INTERPRETATION: The financial costs of introducing RTS,S are comparable with costs of introducing other new vaccines. Country resource requirements for malaria vaccine introduction are most influenced by vaccine price and potential donor funding for vaccine purchases and introduction support.

BACKGROUND: During the COVID-19 pandemic, several vaccines received approval for children aged 18 or younger. Parents' decisions to accept vaccines play an important role in the success of vaccination campaigns. The Health Belief Model (HBM) may explain its association with vaccine acceptance. This study examined parents' Pfizer-BioNTech and Sinopharm vaccine acceptance for their children and its association with HBM. METHODS: A cross-sectional study was conducted in March 2022 using an online survey. Respondents were parents of children aged 5-18 in public and private schools. The multistage random sampling technique was used to choose schools and respondents. Multivariable analysis was conducted to examine the association between vaccine acceptance and HBM. RESULTS: The response rate was 55 %. Of 1,056 respondents, 80.1 % were female, with a mean age of 41, and 95.8 % were not health professionals. Pfizer-BioNTech had a greater acceptance rate than Sinopharm (90 % v.s. 36 %). The Multivariable analysis shows that perceived benefits (aOR = 25.30, 95 %CI = 10.02-63.89 and aOR = 17.94, 95 %CI = 9.56-33.66 for Pfizer-BioNTech and Sinopharm, respectively) and perceived barriers (aOR = 0.06, 95 %CI = 0.01-0.50 and aOR = 0.20, 95 %CI = 0.11-0.40 for Pfizer-BioNTech and Sinopharm, respectively) were associated with vaccine acceptance for both vaccines. Education was associated with Pfizer-BioNTech vaccine acceptance (aOR = 0.96, 95 %CI 0.71-1.29). CONCLUSIONS: The respondents were more confident in Pfizer-BioNTech than Sinopharm. Perceived barriers and perceived benefits were strongly associated with the respondents' vaccine acceptance for both vaccines. During epidemics and pandemics, the government needs vaccines with high efficacy and safety for a higher chance of parents' vaccine acceptance. Future research should examine vaccine costs as perceived barriers for a newly out-of-pocket developed vaccine.

This study explored the differences in COVID-19 vaccination readiness based on the 7C model and its association with vaccine acceptance among foreign-born immigrants, Japan-born immigrants, and locals in Japan. A cross-sectional survey was conducted in October 2021 (n = 3,690). Our results show that COVID-19 vaccination readiness, acceptance, and their relationship differ according to migratory status and nativity. Immigrant participants reported higher general vaccination readiness and acceptability for vaccination against COVID-19 than the Japanese participants, but had lower vaccination coverage, particularly among those born in Japan. The psychological determinants of Japan-born immigrants were more similar to those of Japanese participants than those of foreign-born immigrants. The effects of confidence, complacency, and constraints on COVID-19 vaccine acceptance were strong among all three groups. However, the role of collective responsibility and conspiracy varied by migratory status. This study highlighted the importance of culturally tailored interventions in vaccine delivery to immigrants.

BACKGROUND: After the acute infection, COVID-19 can produce cardiac complications as well as long-COVID persistent symptoms. Although vaccination against COVID-19 represented a clear reduction in both mortality and ICU admissions, there is very little information on whether this was accompanied by a decrease in the prevalence of post-COVID cardiac complications. The aim of this study was to analyze the relationship between COVID-19 vaccination and the prevalence of post-COVID cardiac injury assessed by echocardiogram, and long-COVID persistent cardiac symptoms. METHODS: All patients who consulted for post-COVID evaluation 14 days after discharge from acute illness were included. Patients with heart disease were excluded. The relationship between complete vaccination scheme (at least two doses applied with 14 days or more since the last dose) and pathological echocardiographic findings, as well as the relationship of vaccination with persistent long-COVID symptoms, were evaluated by multivariate analysis, adjusting for age, sex and clinical variables that would have shown significant differences in univariate analysis. RESULTS: From 1883 patients, 1070 patients (56.8%) suffered acute COVID-19 without a complete vaccination scheme. Vaccination was associated with lower prevalence of cardiac injury (1.35% versus 4.11%, adjusted OR 0.33; 95% CI 0.17-0.65, p=0.01). In addition, vaccinated group had a lower prevalence of persistent long-COVID symptoms compared to unvaccinated patients (10.7% versus 18.3%, adjusted OR 0.52; 95% CI 0.40-0.69, p<0.001). CONCLUSION: Vaccination against COVID-19 was associated with lower post-COVID cardiac complications and symptoms, reinforcing the importance of fully vaccinating the population.

BACKGROUND: Taiwan increased the Bacillus Calmette-Guerin (BCG) vaccination age from 24 h after birth to 5-8 months of age to lower BCG-related osteitis/osteomyelitis in 2016. However, the sequences of skin changes at the injection site and in the corresponding lymph nodes are unknown for infants vaccinated at an older age. METHODS: We prospectively collected the photographs of skin reactions within 6 months after vaccination. The type, size, onset time, and duration of the skin reactions were recorded and analyzed. RESULTS: We enrolled 532 infants. The types and median times at onset of skin reactions were as follows: erythema at week 1, induration at week 3, ecchymosis at week 4, and ulceration at week 6. The peak skin responses were at week 6, with average sizes of 8.4 mm, 7.4 mm, and 8.2 mm for erythema, induration, and ecchymosis, respectively. The duration of induration was long, with 57.6 % and 23 % of the infants still having a response at week 12 and 24, respectively. The rate of induration size ≥ 20 mm was 1.7 % (95 % confidence interval: 0.8 %-3.2 %). Overall, 46.4 % of the infants experienced ulcerative change, with most occurring at week 6 (34.1 %), and 9.5 % and 4.1 % of the infants still had ulceration at week 12 and 16, respectively. Twelve infants (2.3 %) had spontaneous resolution of regional lymphadenitis, with the onset time ranging from week 1 to 12. All infants had developed a scar at the end of follow-up. CONCLUSION: Our study demonstrates the typical appearance and time courses of skin reactions in infants who received the BCG vaccination at older than 5 months of age. Infants vaccinated at this age may have a more potent skin response with longer induration and ulceration than those vaccinated at birth.

While effective at preventing Zaire ebolavirus (ZEBOV) disease, cellular immunity to ZEBOV and vector-directed immunity elicited by the recombinant vesicular stomatitis virus expressing ZEBOV glycoprotein (rVSVΔG-ZEBOV-GP) vaccine remain poorly understood. Sera and peripheral blood mononuclear cells were collected from 32 participants enrolled in a prospective multicenter study [ClinicalTrials.gov NCT02788227] before vaccination and up to six months post-vaccination. IgM and IgG antibodies, IgG-producing memory B cells (MBCs), and T cell reactivity to ZEBOV glycoprotein (ZEBOV-GP), vesicular stomatitis virus-Indiana strain (VSV-I) matrix (M) protein, and VSV-I nucleoprotein (NP) were measured using ELISA, ELISpot, and flow cytometry, respectively. 11/32 (34.4%) participants previously received a different investigational ZEBOV vaccine prior to enrollment and 21/32 (65.6%) participants were ZEBOV vaccine naïve. Both ZEBOV vaccine naïve and experienced participants had increased ZEBOV-GP IgG optical densities (ODs) post-rVSVΔG-ZEBOV-GP vaccination while only ZEBOV vaccine naïve participants had increased ZEBOV-GP IgM ODs. Transient IgM and IgG antibody responses to VSV-I M protein and NP were observed in a minority of participants. All participants had detectable ZEBOV-GP specific IgG-producing MBCs by 6 months post-vaccination while no changes were observed in the median IgG-producing MBCs to VSV-I proteins. T cell responses to ZEBOV-GP differed between ZEBOV vaccine experienced and ZEBOV vaccine naïve participants. T cell responses to both VSV-I M protein and VSV-I NP were observed, but were of a low magnitude. The rVSVΔG-ZEBOV-GP vaccine elicits robust humoral and memory B cell responses to ZEBOV glycoprotein in both ZEBOV vaccine naïve and experienced individuals and can generate vector-directed T cell immunity. Further research is needed to understand the significance of pre-existing vector and target antigen immunity on responses to booster doses of rVSVΔG-ZEBOV-GP and other rVSV-vectored vaccines.

The increased demand for yellow fever (YF) vaccines over the last decade, along with insufficient availability of specific pathogen-free embryonated eggs required for timely vaccine production, has led to global YF vaccine shortages. A new live-attenuated YF vaccine candidate (generically referred to as vYF) cloned from a YF-VAX® vaccine (YF-17D vaccine) substrain adapted for growth in Vero cells cultured in serum-free media is currently in development. Here, we assessed the safety and immunogenicity of vYF, and its protective activity upon virulent challenge with wild-type yellow fever virus (YFV) Asibi, compared to licensed YF-17D vaccines in the translational cynomolgus macaque model. vYF was well tolerated with no major safety concerns. Vaccine-related safety observations were limited to minimal/minor microscopic findings at the injection sites and in the draining lymph nodes, consistent with expected stimulation of the immune system. vYF induced early differential expression of genes involved in antiviral innate immunity previously described in humans vaccinated with YF-17D vaccines, as well as YFV-specific IgM and IgG antibodies, high and sustained YFV neutralizing antibody titers from Day 14 up to at least Day 258 post-immunization, IgM+ and IgG+ memory B cells from Day 14 up to at least Day 221 post-vaccination, and Th1 interferon (IFN)-γ and interleukin (IL)-2 secreting effector and memory T cells. Additionally, vYF provided effective resistance to virulent challenge with wild-type YFV Asibi including complete protection against YFV-induced mortality, pathology, dysregulation of blood and liver soluble biomarkers, and a significant reduction in viremia and viral load to the limit of detection. These NHP data suggest that vYF would provide protection against YFV infection in practice, at least similar to that achieved with currently marketed YF-17D vaccines.

Mucosal vaccines offer several advantages over transdermal vaccines, including the ability to acquire systemic and mucosal immunities. Smoking is a huge public health threat and major risk factor for various diseases that exacerbate or prolong respiratory symptoms and conditions. However, its impact on the efficacy of mucosal vaccines remains partially explored. Thus, this study investigates the effects of smoking on mucosal vaccine reactivity by assessing the induction of Th1 immunity, a vital response in infection defense. Cigarette smoke condensate was prepared as a substitute for mainstream smoke. We intranasally administered diphtheria toxoid as an antigen and natural CpG oligonucleotide G9.1, which enhances the Th1-type antibody (Ab) response in a plasmacytoid dendritic cells (pDCs) dependent manner, as an adjuvant to mice to assess the effect of cigarette smoke condensate on Ab responses. The mechanism of its effect was evaluated using human peripheral blood mononuclear cells and their pDC-rich fraction cultured with or without G9.1. In mice, cigarette smoke condensate tended to decrease diphtheria toxoid-specific Ab response, with a higher reduction in Th1-type IgG2 Ab response than in Th2-type IgG1 Ab response. In human peripheral blood mononuclear cells, cigarette smoke condensate significantly reduced the induction of IFN-α production by G9.1. Moreover, G9.1-induced increases in the CD83 expression in pDCs and the CD80 expression in DCs were suppressed via treatment with cigarette smoke condensate. Among the mechanisms suggested were decreased expression of toll-like receptor 9 mRNA, decreased expression of mRNA for IFN regulatory factor 7, and increased CpG methylation of its promoter region. The analysis of Tbet and GATA3 expressions revealed that cigarette smoke condensate exhibits Th1-directed immunostimulatory activity at a steady state but becomes more Th2-directed under G9.1 stimulation. In conclusion, smoking could reduce mucosal vaccine responses by decreasing pDC activation and, consequently, Th1-dominant immunity.

INTRODUCTION: For Brazilian adults, pneumococcal vaccines have been usually taken only by those who are at higher risk for development of pneumococcal diseases. Since populations from lower socioeconomic status are at high risk of acquiring pneumococcal infections, we investigated the carriage prevalence, colonization risk factors, capsular and surface protein types, and antimicrobial resistance among pneumococcal isolates recovered from adults living in a Brazilian urban slum. METHODS: Between September-December 2016, we conducted a cross-sectional study among individuals aged ≥ 18 years who attended a public primary clinic in Niterói/RJ, Brazil. Pneumococci were isolated by culture on sheep blood agar plates with and without gentamicin. Antimicrobial susceptibility was determined for all isolates. We used PCR to determine capsular types, PspA families (Fam) and pilus islets (PI). RESULTS: Of 385 adults, 32 (8.3 %) were pneumococcal carriers. Three carriers had two different pneumococci, totaling 35 isolates. After multivariate analysis, smoking, previous hospitalization, alcohol consumption and co-habitation with children aged < 6 years increased the odds of pneumococcal carriage, but antibiotic use in the previous 2 weeks was found to be a protective factor. Fourteen different serogroups/serotypes were detected and the prevalent ones were 9 N/L, 10A, 15B/C and 35F/47F (n = 3; 8.6 % each). Non-typeable (NT) isolates made up 31.4 %. All isolates were susceptible to chloramphenicol, levofloxacin and vancomycin. We found eight (22.9 %) penicillin non-susceptible pneumococci (PNSP) with minimum inhibitory concentrations (MICs) of 0.38-1.5 μg/mL. The two (5.7 %) erythromycin-resistant isolates had MIC > 256 μg/mL, cMLSB phenotype and the erm(B) gene. Twelve (34.3 %) and 17 (48.6 %) isolates had PspA Fam1 and Fam2, respectively. Three (8.6 %) isolates had genes for pilitwo PI-1 and one PI-2. CONCLUSION: We detected a low frequency of pneumococcal carriage among the adult population, but a high diversity of serotypes. Frequencies of PNSP and NT isolates resistant to antimicrobial agents are concerning.

OBJECTIVES: To explore acceptability of and preferences for the introduction of varicella vaccination to the UK childhood immunisation schedule. DESIGN: We conducted an online cross-sectional survey exploring parental attitudes towards vaccines in general, and varicella vaccine specifically, and their preferences for how the vaccine should be administered. PARTICIPANTS: 596 parents (76.3% female, 23.3% male, 0.4% other; mean age 33.4 years) whose youngest child was aged 0-5 years. MAIN OUTCOME MEASURES: Willingness to accept the vaccine for their child and preferences for how the vaccine should be administered (in combination with the MMR vaccine [MMRV], on the same day as the MMR vaccine but as a separate injection [MMR + V], on a separate additional visit). RESULTS: 74.0% of parents (95% CI 70.2% to 77.5%) were extremely/somewhat likely to accept a varicella vaccine for their child if one became available, 18.3% (95% CI 15.3% to 21.8%) were extremely/somewhat unlikely to accept it and 7.7% (95% CI 5.7% to 10.2%) were neither likely nor unlikely. Reasons provided by parents likely to accept the vaccine included protection from complications of chickenpox, trust in the vaccine/healthcare professionals, and wanting their child to avoid their personal experience of chickenpox. Reasons provided by parents who were unlikely included chickenpox not being a serious illness, concern about side effects, and believing it is preferable to catch chickenpox as a child rather than as an adult. A combined MMRV vaccination or additional visit to the surgery were preferred over an additional injection at the same visit. CONCLUSIONS: Most parents would accept a varicella vaccination. These findings highlight parents' preferences for varicella vaccine administration, information needed to inform vaccine policy and practice and development of a communication strategy.

OBJECTIVE: Malaria contributes to an enormous global burden of disease and mortality, especially in children. Approximately one in every four global cases and deaths from malaria occurs in Nigeria. This study aims to evaluate the prevalence and correlates of community hesitancy to the malaria vaccine, including the reasons for the hesitancy, following the approval of the RTS,S malaria vaccine by the World Health Organization (WHO). METHODS: This was a nationwide cross-sectional online survey of Nigerian adults conducted from 20th October to 30th November 2021. Participants who replied 'no' or 'maybe' to a question assessing their willingness to accept the RTS,S malaria vaccine were considered "hesitant". We fit a multivariate logistic regression model to report the adjusted odds ratio (aOR) and 95 % confidence interval (CI) for the factors associated with vaccine hesitancy. FINDINGS: Among 3377 total respondents (1961 [57.86 %] males; mean age [SD]: 30[9.1]), 1010 (29.91 %) were hesitant. Receiving information about the RTS,S malaria vaccine initially from healthcare workers (vs. the internet) (aOR:0.55; 95 % CI:0.35-0.87) was significantly associated with lower odds of hesitancy. Conversely, earning a high income of over NGN100, 000 (vs. < NGN 30,000) per month (aOR: 2.10, 95 % CI: 1.36-3.24), belonging to other religious groups (vs. Islam) (aOR:3.25, 95 % CI:1.18-8.98), and having a family size of more than ten (vs. < 5) (aOR:1.84; 95 % CI:1.08-3.13) were significantly associated with a higher odds of hesitancy. The main reasons for vaccine hesitancy included fear of vaccine adverse effects (34.95 %), availability of other malaria preventive measures (33.96 %) and not seeing the positive effect of the vaccine in others first (32.97 %). CONCLUSION: The findings of this survey provide a valuable blueprint for the development of targeted interventions to facilitate caregiver acceptance of the RTS,S vaccine.

OBJECTIVE: Evaluation of covid‑19 vaccine hesitancy among pregnant women and their reported reasons for vaccine refusal. METHODS: This prospective study was performed in Arash women's Hospital, Tehran, Iran, between December 1, 2021 and January 1, 2022. All pregnant women who were attended to prenatal care unit were considered eligible for inclusion. A validated questionnaire was used for data gathering. Written informed consent was obtained from all participants. RESULTS: Finally, 477 pregnant women were recruited and were divided into two groups according the status of vaccine acceptance (237 accepted and 240 women refused vaccination). The mean age of accepted participants was higher (31.65 ± 5.69 vs 30.39 ± 5.5; P = 0.01). There was a significant statistical difference between the groups regarding education level. Access to internet and social media were also significantly different between the two groups (94.8% in accepted vs 86.6% in refused group; P = 0.002). There was more rate of severe COVID-19 infection in friends or relatives of accepted group (50% vs 38%). we did not find any statistically significant differences in obstetric characteristics and the rate of obstetric complications between the two groups. The most common reasons reported by participants for vaccine refusal, was fear of vaccination side effects on the fetus (86.5%), and the less common reported reasons were husband's disagreement (9.7%), use of traditional medicine (5.6%), religious beliefs (3.7%), and information obtained from social media (2.8%). After advices from medical staff, most of these mothers (86.5%) still refused vaccination. CONCLUSION: Based on the results of the present study,rate of COVID-19 vaccine hesitancy was about 50% and its most common reported reason was fear of probable side effects of vaccine on the fetus.

BACKGROUND: Increasing vaccine coverage remains the best way to control the COVID-19 pandemic. Healthcare personnel (HCP) have long been the most credible and frequently used source of vaccine information for the public, and an HCP recommendation is a strong predictor of vaccination. METHODS: A survey of HCP was conducted in September 2021 via a double opt-in network panel. Responses to survey items were summarized and stratified by HCP type and adjusted logistic regression models were fitted. RESULTS: >94% of the 1074 HCP surveyed reported receiving at least one dose of COVID-19 vaccine or intending to soon, with vaccinating most common among pediatricians (98%), followed by family medicine doctors (96%), pharmacists (94%), and nurses/nurse practitioners/physician assistants (88%). HCP with high trust in the Centers for Disease Control and Prevention had 26 times the odds of vaccinating of HCP with low trust (95%CI: 9, 74). Nearly half of unvaccinated HCP (47%) were concerned about side effects, and one third of unvaccinated HCP (33%) were concerned the vaccine was developed too quickly. About three quarters of HCP reported strongly recommending the Pfizer-BioNTech (75%) and Moderna (70%) vaccines to their patients, compared to about one quarter (24%) strongly recommending Johnson & Johnson. CONCLUSIONS: Although most HCP are vaccinated against COVID-19 and strongly recommend vaccination to their patients, some harbor similar concerns to the public. Additional resources - regularly updated to explain the progressing scientific landscape and address ever evolving public concerns - are needed to further improve vaccine coverage among HCP and aid them in supporting the decision-making of their patients.

Education is key to behavioural adoption and acceptability of health interventions. We evaluated the impact of an educational intervention administered 1:1 to individuals incarcerated in four Canadian federal prisons on COVID-19 vaccine uptake. Eligible individuals (those who had refused all COVID-19 vaccines) were randomized 2:1 to receive the educational intervention or not (control group); those who received the intervention completed questionnaires assessing COVID-19 vaccine-related knowledge, attitudes, and beliefs pre- and post-educational intervention. The primary and secondary outcome measures were COVID-19 vaccine uptake and vaccine confidence, respectively. Between May 3 and September 9, 2022, 202 participants were randomized to receive the intervention, of whom 127 (63 %) agreed to participate. Participants who were randomized to the intervention had higher COVID-19 vaccine uptake vs. the control group (5 % vs 1 %, p = 0.046). COVID-19 vaccine-related knowledge, attitudes, and beliefs improved post-intervention. Education increases COVID-19 vaccine uptake and confidence among people in Canadian federal correctional facilities.