Association between human papillomavirus vaccination and serious adverse events in South Korean adolescent girls: nationwide cohort study

Effect of information awareness on attitudes toward human papillomavirus vaccination intentions in Japan

Background

The Human Papillomavirus (HPV) vaccination rate among Japanese high school girls remains critically low, reflecting ongoing public apprehension and misinformation. This study explores the relationship between information presentation and attitudes toward HPV vaccination in Japan.

Methods

We conducted a web-based survey of female high school students aged 15 to 16 and mothers of daughters of similar age across Japan. The first screening questionnaire investigated the vaccine uptake among eligible students. The detailed questions assessing awareness of HPV vaccination information, including vaccine eligibility and its cost, effectiveness, lifetime prevalence of HPV infection, and vaccine safety, were asked to the respondents. After presenting each piece of information, we investigated how the information influenced the vaccination attitudes of unvaccinated students and mothers of unvaccinated girls.

Results

Data collection occurred from August 20 to August 24, 2021. Of 473 students, 68 (14.4 %) had already been vaccinated before the study. Over half of the 245 participating students were aware of vaccine eligibility and cost (68.7 %) and effectiveness (63.6 %), but fewer understood lifetime prevalence (28.7 %) and safety (45.3 %). In contrast, awareness of the same questions in 245 mothers was higher than that in the students: 90.2 %, 92.5 %, 55.4 %, and 61.1 %, respectively. Among unvaccinated students and mothers of unvaccinated girls, the intention to get vaccinated increased the most after being informed about the lifetime risks of HPV infection; 50.5 % of students and 38.8 % of mothers showed a positive attitude toward the HPV vaccination.

Conclusions

Bridging the awareness gap between students and mothers is crucial for improving HPV vaccination rates. The findings underscore the potential of specific, targeted information to influence vaccination intentions, particularly regarding the HPV infection rate.

Potential immunological triggers for narcolepsy and idiopathic hypersomnia: Real-world insights on infections and influenza vaccinations

OBJECTIVE

It is hypothesized that narcolepsy type 1 (NT1) develops in genetically susceptible people who encounter environmental triggers leading to immune-mediated hypocretin-1 deficiency. The pathophysiologies of narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH) remain unknown. The main aim of this study was to collect all reported immunological events before onset of a central disorder of hypersomnolence.

METHODS

Medical records of 290 people with NT1, and 115 with NT2 or IH were retrospectively reviewed to extract infection and influenza vaccination history. Prevalence, distribution of immunological events, and time until hypersomnolence onset were compared between NT1 and the combined group of NT2 and IH.

RESULTS

Immunological events were frequently reported before hypersomnolence disorder onset across groups. Flu and H1N1 influenza vaccination were more common in NT1, and Epstein-Barr virus and other respiratory and non-respiratory infections in NT2 and IH. Distributions of events were comparable between NT2 and IH. Rapid symptom onset within one month of infection was frequent across groups, especially after flu infection in NT1. Hypersomnolence disorder progression after an immunological event was reported in ten individuals.

CONCLUSIONS

Our findings suggest a variety of immunological triggers potentially related to NT1, including H1N1 influenza infection or vaccination, infection with other flu types, and other respiratory and non-respiratory infections. Frequent reports of immunological events (other than those reported in NT1) immediately prior to the development of NT2 and IH support the specificity of triggers for NT1, and open important new research avenues into possible underlying immunological mechanisms in NT2 and IH.

Effect of the human papillomavirus vaccine on the risk of genital warts: a nationwide cohort study of Korean adolescent girls

OBJECTIVES

The purpose of this study was to assess the effectiveness of human papillomavirus (HPV) vaccination administered to adolescent girls through Korea's National Immunization Program.

METHODS

This retrospective cohort study included patients who were 12-13 years old, whether vaccinated or unvaccinated, between July 2016 and December 2017. The incidence of genital warts (GWs) was monitored through 2021. Time-stratified hazard ratios (HRs) were estimated, adjusting for birth year, socioeconomic status, and the level of urbanization of the region, and were presented with 95% confidence intervals (CIs). Data were sourced from the Immunization Registry Integration System, linked with the National Health Information Database.

RESULTS

The study included 332,062 adolescent girls, with an average follow-up period of approximately 4.6 years. Except for the first year, the HRs for the vaccinated group were lower than those for the unvaccinated group. The HRs for specific cut-off years were as follows: year 2, 0.62 (95% CI, 0.31 to 1.13); year 3, 0.58 (95% CI, 0.35 to 0.96); and year 4 and beyond, 0.39 (95% CI, 0.28 to 0.52).

CONCLUSIONS

Our findings indicate that HPV vaccination was associated with a reduction in the risk of GWs among adolescent girls. Notably, this reduction became significant as the incidence of GWs increased with age.

Autoimmune disorders reported following COVID-19 vaccination: A disproportionality analysis using the WHO database

PURPOSE

Owing to adverse event following immunization (AEFI) related to autoimmune disorders and coronavirus disease 2019 (COVID-19) vaccines sharing common biological mechanisms, identifying the risk of AEFIs associated with COVID-19 vaccines remains a critical unmet need. We aimed to assess the potential safety signals for 16 AEFIs and explore co-reported adverse events (AEs) and drugs using the global database of the World Health Organization, VigiBase.

METHODS

We assessed the occurrence of 16 AEFIs following COVID-19 vaccination through the Standardized MedDRA Queries group "Immune-mediated/Autoimmune Disorders" from MedDRA and performed a disproportionality analysis using reporting odds ratio (ROR) and information component (IC) with 95% confidence intervals (CIs).

RESULTS

We identified 25,219 events associated with COVID-19 vaccines in VigiBase. Although rare, we detected four potential safety signals related to autoimmune disorders following COVID-19 vaccination, including ankylosing spondylitis or psoriatic arthritis (ROR 1.86; 95% CI 1.53-2.27), inflammatory bowel disease (ROR 1.77; 95% CI 1.60-1.96), polymyalgia rheumatica (ROR 1.42; 95% CI 1.30-1.55), and thyroiditis (ROR 1.40; 95% CI 1.30-1.50), with positive IC025 values. The top co-reported AEs were musculoskeletal disorders, and immunosuppressants were the most representative co-reported drugs.

CONCLUSION

In addressing the imperative to comprehend AEFI related to autoimmune disorders following COVID-19 vaccination, our study identified four potential safety signals. Thus, our research underscores the importance of proactive safety monitoring for the identification of the four AEFIs following COVID-19 vaccination, considering the associated advantages.

Cardiovascular, Neurological, and Immunological Adverse Events and the 23-Valent Pneumococcal Polysaccharide Vaccine

Importance

Despite widespread immunization with the 23-valent pneumococcal polysaccharide vaccine (PPSV23), safety concerns remain owing to a lack of statistical power and largely outdated evidence.

Objective

To evaluate the association between cardiovascular, neurological, and immunological adverse events and PPSV23 vaccination in older adults.

Design, Setting, and Participants

This population-based cohort study using a self-controlled risk interval design used a large linked database created by linking the Korea Immunization Registry Information System and the National Health Information Database (2018 to 2021). Participants included patients aged 65 years or older with a history of PPSV23 vaccination and incident cardiovascular, neurological, or immunological events during the risk and control intervals. Data were analyzed from November 2022 to April 2023.

Exposure

23-valent pneumococcal polysaccharide vaccine.

Main Outcomes and Measures

The occurrence of 1 among 6 cardiovascular events (myocardial infarction, atrial fibrillation, cardiomyopathy, heart failure, hypotension, and myocarditis or pericarditis), 2 neurological events (Bell palsy and Guillain-Barré syndrome), and 3 immunological events (sepsis, thrombocytopenia, and anaphylaxis) during the risk and control periods. The risk and control intervals were defined as 1 to 28 and 57 to 112 days after PPSV23 vaccination, respectively. Conditional Poisson regression was used to estimate the incidence rate ratio (IRR) with a 95% CI.

Results

Altogether, 4355 of the 1 802 739 individuals who received PPSV23 vaccination and experienced at least 1 outcome event were included (mean [SD] age, 72.4 [8.2] years; 2272 male participants [52.1%]). For cardiovascular events, there were no significant associations for myocardial infarction (IRR, 0.96; 95% CI, 0.81-1.15), heart failure (IRR, 0.85; 95% CI, 0.70-1.04), and stroke (IRR, 0.92; 95% CI, 0.84-1.02). Similarly, no increased risks were observed for neurological and immunological outcomes: Bell palsy (IRR, 0.95; 95% CI, 0.72-1.26), Guillain-Barré syndrome (IRR, 0.27; 95% CI, 0.06-1.17), sepsis (IRR, 0.99; 95% CI, 0.74-1.32), and thrombocytopenia (IRR, 1.18; 95% CI, 0.60-2.35).

Conclusions and Relevance

In this self-controlled risk interval study, there was no appreciable increase in risk for most cardiovascular, neurological, or immunological adverse events following PPSV23. The updated safety profile of PPSV23 provides supportive evidence for the establishment of immunization strategies for older adults.

Post-marketing surveillance study of the safety of the HPV-16/18 vaccine in Korea (2017-2021)

Human papillomavirus (HPV) infection is associated with the risk of developing certain cancers, including cancers of the cervix, vulva, vagina, penis, anus, rectum, and oropharynx. In 2016, the bivalent HPV-16/18 vaccine was included in the Korea National Immunization Program. This vaccine protects against HPV types 16 and 18 and other oncogenic HPV types predominant in cervical and anal cancers. This post-marketing surveillance (PMS) study assessed the safety of the HPV-16/18 vaccine in Korea. The study was conducted in males and females aged between 9 and 25 years, from 2017 to 2021. Safety was measured in terms of frequency and intensity of adverse events (AEs), adverse drug reactions (ADRs), and serious adverse events (SAEs) after each vaccine dose. The safety analysis included all participants who were vaccinated as per prescribing information and who completed a 30-day follow-up after at least one dose. Data were collected using individual case report forms. The total safety cohort included 662 participants. A total of 220 AEs were reported in 144 subjects (21.75%), and there were 158 ADRs in 111 subjects (16.77%), with the most common being injection site pain in all cases. No SAEs or serious ADRs were reported. Most AEs were reported after the first dose and were injection site reactions with mild intensity that recovered. No individuals required hospitalization or an emergency department visit. Safety results showed that the HPV-16/18 vaccine was generally well tolerated in the Korean population, and no safety concerns were identified.ClinicalTrials.gov Identifier: NCT03671369.

Association between human papillomavirus infection or immunization and risk for rheumatoid arthritis

Background

Human papillomavirus (HPV) is a virus primarily transmitted through sexual contact. Little is known about the association between HPV infection or immunization and the risk for rheumatoid arthritis (RA). The purpose of this study was to evaluate whether HPV infection or immunization is related to the risk for RA in adults.

Methods

Data were obtained from the 2007-2016 National Health and Nutrition Examination Survey (NHANES). We developed three independent multivariate logistic regression models to evaluate the association between HPV infection or immunization and the risk for RA in adults.

Results

Finally, we analyzed 15,677 and 8,944 subjects, respectively. In all models, HPV infection was positively associated with an increased prevalence of RA in adults aged 18-59 years, with the highest value of the odds ratio (OR) in model 2 (after weighting: OR 1.095, 95% CI 1.092, 1.097), whereas HPV immunization significantly reduced the prevalence of RA in adults aged 18-59 years, with the lowest OR in model C (after weighting: OR 0.477, 95% CI 0.472, 0.481). These associations persisted after correction for confounders such as age, sex, race, education level, marital status, smoking, diabetes, hypertension, hyperlipidemia, and BMI.

Conclusion

In summary, our study suggests that HPV infection is positively associated with the prevalence of RA in adults, and HPV immunization can reduce the prevalence of RA in adults. However, our findings need more powerful to prove these associations through rigorously designed prospective studies.

Human Papillomavirus vaccination clinical decision support for young adults in an upper midwestern healthcare system: a clinic cluster-randomized control trial

INTRODUCTION

Human papillomavirus (HPV) vaccination rates are low in young adults. Clinical decision support (CDS) in primary care may increase HPV vaccination. We tested the treatment effect of algorithm-driven, web-based, and electronic health record-linked CDS with or without shared decision-making tools (SDMT) on HPV vaccination rates compared to usual care (UC).

METHODS

In a clinic cluster-randomized control trial conducted in a healthcare system serving a largely rural population, we randomized 34 primary care clinic clusters (with three clinics sharing clinicians randomized together) to: CDS; CDS+SDMT; UC. The sample included young adults aged 18-26 due for HPV vaccination with a study index visit from 08/01/2018-03/15/2019 in a study clinic. Generalized linear mixed models tested differences in HPV vaccination status 12 months after index visits by study arm.

RESULTS

Among 10,253 patients, 6,876 (65.2%) were due for HPV vaccination, and 5,054 met study eligibility criteria. In adjusted analyses, the HPV vaccination series was completed by 12 months in 2.3% (95% CI: 1.6%-3.2%) of CDS, 1.6% (95% CI: 1.1%-2.3%) of CDS+SDMT, and 2.2% (95% CI: 1.6%-3.0%) of UC patients, and at least one HPV vaccine was received by 12 months in 13.1% (95% CI: 10.6%-16.1%) of CDS, 9.2% (95% CI: 7.3%-11.6%) of CDS+SDMT, and 11.2% (95% CI: 9.1%-13.7%) of UC patients. Differences were not significant between arms. Females, those with prior HPV vaccinations, and those seen at urban clinics had significantly higher odds of HPV vaccination in adjusted models.

DISCUSSION

CDS may require optimization for young adults to significantly impact HPV vaccination.

TRIAL REGISTRATION

clinicaltrials.gov NCT02986230, 12/6/2016.

The lifestyle factors of physical activity and diet balance associated with HPV infection in China: The cross-sectional study

Background

Human wellbeing has been linked with lifestyle factors such as physical activity, diet balance, sleep quality, depression, and anxiety. However, few studies illustrate the relationship between such lifestyle factors and HPV infection. In this study, we investigated the association between lifestyle factors, age, disease status and HPV infection.

Participants and methods

Participants were recruited through a digital eHealth platform in Shenzhen, Mainland China. Both lifestyle factors and cervicovaginal mucus (CVM) samples to test for HPV outcomes were collected from each participant as a cross-sectional study. In addition, the eHealth platform recorded age and current or history diseases, which were adjusted to apply for both univariable and multivariable logistic regression. Furthermore, lifestyle factors were categorized as different levels to conduct stratification analysis.

Results

We recruited 149 HPV positive and 346 HPV negative participants through HPV detection. Physical activity and diet balance were significantly associated with HPV infection in lifestyle factors (P values < 0.001) after adjusting for age and current or history diseases. However, stratified analysis showed three factors were insignificant for HPV infection - namely, sleep quality, depression, and anxiety. Most HPV infections involved a sole HPV serotype (83%), and diet balance was the most significant difference between sole and multiple HPV infections.

Conclusions

Among lifestyle factors, physical inactivity or diet imbalance can significantly increase HPV infection risk. In particular, diet balance might be related to the number of HPV serotypes. Our results suggest that exercising and regulating diet may reduce the risk of HPV infection.

Change of HPV vaccination rates in Japan: the effect of individual notifications implemented by local governments

BACKGROUND

In Japan, in June 2013, The Ministry of Health, Labor and Welfare (MHLW) decided to temporarily suspend its official recommendation for the participation of girls in the national immunization program. The HPV vaccination rate in Japan soon declined to below 1%. In October 2020, the MHLW notified that the municipalities could and should begin to individually notify girls and their parents targeted for routine vaccination. We have examined how that type of individual notification has affected the number of vaccinations.

METHODS

From 12 municipalities (with a combined total population of approximately 4.06 million), we collected vaccination data for all girls who attended grades 6 through 10 from April 2019 to March 2021. We analyzed the number of initial-round vaccinations that occurred by month and the timing and the subjects of the individual notifications.

RESULTS

The annual vaccination rate for tenth-grade students in 2020 in the six municipalities that had implemented individual notification was 9.46% (342/3618), which was significantly higher than the rate of 3.22% (54/1676) in the three municipalities that had not implemented individual notification (p < 0.001). On the other hand, the annual vaccination rate for the sixth to ninth-grade students in 2020 in the six municipalities that had implemented individual notification was not significantly (p = 0.56) higher than the rate in the three municipalities that did not: 1.43% (197/13,785) versus 1.33% (83/6260), respectively.

CONCLUSION

This study clearly demonstrates the importance of providing information for routine vaccination directly to the targets and their parents.

Assessment of thyroiditis risk associated with HPV vaccination among girls aged 9-18 years: A time-varying cohort study

BACKGROUND

Previous studies have suggested a relationship between human papillomavirus vaccine and autoimmune diseases, including thyroiditis. Thus, we aimed to evaluate the risk of thyroiditis associated with HPV vaccination among girls using the Primary Care Database For Pharmacoepidemiological Research (BIFAP) in Spain.

METHODS

In this retrospective cohort study, girls in BIFAP aged 9-18 years from 2007 to 2016, free of past thyroiditis and HPV vaccination, were included. Hazard Ratios (HRs; 95% CI) of thyroiditis were calculated within exposed periods (up to 2 years of vaccination) and post-exposed periods (from 2 years after vaccination onwards) compared with non-exposed periods, overall, by dose and by type of vaccine, adjusted for potential confounders collected at different times. In a post-hoc analysis, we moved back the thyroiditis date (30 days) as a theoretical delay in diagnosis.

RESULTS

Out of the 388,411 girls included in the cohort, 153,924 were vaccinated against HPV and 480 thyroiditis (253 autoimmune) cases were identified (334 non-exposed; 103 exposed; 43 post-exposed). Adjusted HR was 1.18 [95% CI: 0.79-1.76] for exposed (1.25 [0.77-2.04] for bi- and 1.15 [0.76-1.76] for quadri-valent vaccines) and 1.26 [0.74-2.14] for post-exposed periods. HR was 1.50 [0.87-2.59] for the 1^st dose, 1.13 [0.66-1.91] for the 2^nd and 1.11 [0.71-1.72] for the 3^rd one. When the diagnosis date was moved back, the risk was 1.14 [0.76-1.70] for exposed period, being 1.80 [0.86-3.76] and 1.40 [0.74-2.66] after 1^st dose of bi- and quadri-valent, respectively.

CONCLUSIONS

We did not observe an increased risk of thyroiditis following HPV vaccination (whether bi- or quadri-valent). Even though the point estimate was higher after 1^st HPV vaccination dose than after subsequent doses, a dose-effect was not confirmed. Results remained similar after applying a lag time.

Thyroid Inconveniences With Vaccination Against SARS-CoV-2: The Size of the Matter. A Systematic Review

After the beginning of COVID-19 vaccination campaigns, several reports of thyroid disease possibly related to the COVID-19 vaccination progressively appeared in the literature, raising the question of whether the thyroid disorder might be a SARS-CoV-2 vaccine complication. The aim of this study was to analyze the data about COVID-19 vaccination and thyroid disease, evaluate the size and quality of related literature, assess the type of these events, and investigate their timing of onset with respect the vaccination. Pubmed/MEDLINE and Cochrane were systematically reviewed until February 2022 to retrieve the largest number of original papers, case reports, and case series articles reporting thyroid disease after SARS-CoV-2 vaccination. Forty-six articles were included with a total of 99 patients aged from 26 to 73 years were described, of whom 74.75% female. Regarding the vaccination received, 49.49% of patients received Comirnaty (Pfizer/BioNTech), 14.14% CoronaVac (Sinovac), 12.12% Vaxzevria (Oxford/Astrazeneca), 11.11% Spikevax (Moderna), 3.03% Ad26.COV2.S (Janssen, Johnson & Johnson), one patient Covaxin (Bharat Biotech) and one patient Convidecia (Cansino). In 7 cases the thyroid disorder developed after the third dose with a combination of different vaccines. Regarding the type of thyroid disorder, 59 were subacute thyroiditis (SAT), 29 Graves' disease (GD), 2 co-occurrence of SAT and GD, 6 painless thyroiditis (PT), and single cases of thyroid eye disease and hypothyroidism associated with mixedema. The timeline between vaccination and thyroid disorder ranged between 0.5 to 60 days, with an average of 10.96 days. Considering the limited follow-up time, a complete remission was reported in most of SAT and PT cases while a persistence was observed in GD. In conclusion, both size and quality of published data about thyroid inconveniences after COVID-19 vaccination are limited; thyroid disorders may occur within 2 months after COVID-19 vaccination; among all thyroid diseases after COVID-19 vaccination, GD and SAT seem to be more frequent.

No association between enterovirus 71 (EV71) vaccination and risk of febrile seizures: a population-based near real-time surveillance study

BACKGROUND

Since 2016, vaccines against enterovirus 71 (EV71) infection have been approved for use in China. Reports to the national passive surveillance system raised concerns about febrile seizures (FS) after EV71 vaccination. Rapid safety assessment of this novel vaccine is a public health priority. The objective was to assess risks of FS following EV71 vaccination in China.

METHODS

We used data from a Regional Health Information Platform in Ningbo. The exposed population was children aged 6-71 months who received any dose of EV71 vaccine from 1 January 2016 to 31 December 2019. We implemented a multilayered approach to actively monitor FS following EV71 vaccination that included near real-time surveillance using two complementary sequential designs and further signal evaluation performing self-controlled risk interval (SCRI) analyses.

RESULTS

A total of 330,668 EV71 doses were administered to the study population. During 157 weeks of sequential analyses, no statistically increased risks were detected, when compared with the self-matched control interval or the background risk. Further SCRI analyses confirmed no associations between EV71 vaccination and FS (adjusted incidence rate ratio: 1.04, 95% CI: 0.75 to 1.43).

CONCLUSIONS

Our results reassured the safety of FS after EV71 vaccination using postlicensure data for the first time.

Updated clinical guideline for human papillomavirus vaccine: the Korean Society of Gynecologic Oncology guidelines

Since the human papillomavirus (HPV) vaccine guidelines were developed by the Korean Society of Gynecologic Oncology (KSGO) in 2011, 2016, and 2019, several recent studies on the efficacy and safety of HPV vaccines in middle-aged women and men have been reported. Furthermore, there has been an ongoing debate regarding the efficacy of the HPV vaccine in women with prior HPV infection or who have undergone conization for cervical intraepithelial neoplasia (CIN). We searched and reviewed studies on the efficacy and safety of the HPV vaccine in middle-aged women and men and the efficacy of the HPV vaccine in patients infected with HPV and those who underwent conization for CIN. The KSGO updated their guidelines based on the results of the studies included in this review.

Knowledge, Attitude and Practice of Main Stakeholders towards Human Papilloma Virus Infection and Vaccination in Mombasa and Tana-River Counties in Kenya: A Qualitative Study

Following a successful Human Papilloma Virus (HPV) vaccination pilot in 2013-2015 in Kitui county, Kenya introduced the HPV vaccine in October 2019 with a goal to immunize approximately 800,000 girls annually against HPV. Our study assessed the knowledge, attitudes, and practice of affected groups towards HPV infection and vaccination in two counties of Kenya. Semi-structured interviews from children aged between nine and thirteen years and key informants comprising of parents, head teachers, community leaders and health workers involved in HPV vaccination in health facilities from Mombasa and Tana-River counties were conducted. Content was analyzed thematically and coded for emerging themes using the QRS Nvivo 12 Plus (QRS International, Doncaster, Australia) software package. From our findings, a significant proportion of participants, especially children, have limited knowledge of the subject. Vaccination of boys was opposed by most participants. Parents and the community members are not in favor of HPV vaccination, as compared to the other groups. A similar pattern of inadequate knowledge and strongly opposed attitudes was observed in Tana-River and Mombasa. Active community involvement in primary prevention strategies may promote the uptake of the vaccine which can be achieved by robust awareness, modifying the negative beliefs about HPV vaccine and encouraging the perceptibility of HPV vaccination.