The association of adverse events with bivalent human papilloma virus vaccination: A nationwide register-based cohort study in Finland

The Effect of Interventions Based on the Information-Motivation-Behavioral Skills Model on the Human Papillomavirus Vaccination Rate Among 11-13-Year-Old Girls in Central and Western China: Protocol for a Randomized Controlled Trial

BACKGROUND

Persistent infection of high-risk human papillomavirus (HPV) can lead to cervical intraepithelial neoplasia, cervical cancer, and even death. HPV vaccination for girls aged 9-14 years can effectively prevent the occurrence of cervical cancer. Some Chinese provinces and cities have launched free HPV vaccination programs for school-age girls; however, due to the lack of supportive government policies, the high price and supply shortage of HPV vaccines, and vaccine hesitancy, some parents refuse to vaccinate their daughters.

OBJECTIVE

This protocol reports the design of a randomized controlled trial (RCT) aiming to explore the efficacy of a digital HPV vaccination education intervention based on the information-motivation-behavioral skills (IMB) model in improving the HPV vaccination rate among 11-13-year-old girls in central and western China.

METHODS

A multicenter intervention study based on an online applet will be conducted in December 2024, and about 750 eligible parents of 11-13-year-old girls will be assigned in a 1:1 ratio to an intervention group receiving 7-day digital HPV vaccination education based on the IMB model or a control group using non-HPV publicity materials. Free HPV vaccination pilot projects will be carried out among this population by our research team in central and western China (some parents might refuse to vaccinate their daughters). All participants will be asked to complete online questionnaires at baseline; postintervention; and 1 week, 1 month, and 3 months after the intervention.

RESULTS

The primary outcome of this study will be receipt of the first HPV vaccination within 3 months. Data will be analyzed based on an intention-to-treat approach, and Stata 16.0 will be used for statistical analysis.

CONCLUSIONS

This study aims to improve the HPV vaccination rate among 11-13-year-old girls and will examine the impact of a digital HPV vaccination education intervention based on the IMB model. The findings of this study may offer promising intervention measures for HPV vaccine hesitancy in low-health-resource areas in the future.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2300067402; https://tinyurl.com/v5zt4hc9.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/58873.

Human Papillomavirus Vaccination by Birth Fiscal Year in Japan

Importance

The Ministry of Health, Labour, and Welfare (MHLW) of Japan aggregates human papillomavirus (HPV) vaccination data across Japan for each fiscal year (FY) by age at vaccination. Birth FY (BFY)-specific vaccination coverage remains unknown.

Objective

To calculate the BFY-specific vaccination coverage for each FY and the cumulative first-dose coverage for each BFY in Japan, to understand the generation-specific vaccination coverage, and to estimate the cumulative first-dose coverage of each BFY that would be achieved by FY 2028 vs World Health Organization (WHO) targets.

Design, Setting, and Participants

In this cross-sectional study, MHLW-published national age-specific HPV vaccination numbers and demographic data for female individuals were used to calculate the BFY-specific first-dose coverage for each FY and the BFY-specific cumulative first-dose coverage. It was assumed that the BFYs 2007 to 2012 vaccination coverage in FY 2023 to 2028 would remain the same as the vaccination coverage of the same grade in FY 2022 to estimate the cumulative first-dose coverage that would be achieved by FY 2028. Data analysis was performed from December 2023 to January 2024.

Exposure

Two MHLW policy changes were the government's suspension of proactive recommendation for HPV vaccination in June 2013 and the government's resumption of proactive recommendation for HPV vaccination in April 2022.

Main Outcomes and Measures

The primary outcome was generation-specific vaccination coverage among female individuals born in BFYs 1994 to 2010 in FYs 2010 to 2022, calculated using reconfigured published data.

Results

In this study of vaccination data for 9 414 620 female individuals, the generation-specific vaccination coverage was 71.96% for the vaccination generation (BFYs 1994-1999), 4.62% for the vaccine-suspension generation (BFYs 2000-2003), 16.16% for the generation that received information individually (BFYs 2004-2009), and 2.83% for the vaccine-resumed generation (BFY 2010). HPV routine vaccination coverage was extremely low in BFYs 2000 to 2010 (0.84%-25.21%) vs BFYs 1994 to 1999 (53.31%-79.47%). The cumulative first-dose coverage that was estimated to be achieved in the vaccine-resumed generation by FY 2028 plateaued at 43.16%.

Conclusions and Relevance

Even after the resumption of MHLW's proactive recommendations, HPV vaccination coverage has only minimally recovered in Japan. The cumulative first-dose coverage that was estimated to be achieved in the vaccine-resumed generation by FY 2028 is below the WHO target. These findings reveal that stronger cervical cancer control measures are required, particularly for the vaccine-resumed generation, which will plateau at approximately one-half the WHO target values.

Vaccination and the risk of systemic lupus erythematosus: a meta-analysis of observational studies

OBJECTIVE

This meta-analysis aims to explore the potential link between vaccines and systemic lupus erythematosus (SLE).

METHODS

We systematically searched PubMed, Cochrane Library, and Embase for observational studies from inception to September 3, 2023, using medical subject headings (MeSH) and keywords. Study quality was assessed using the NOS scale. Statistical analyses were conducted using STATA software (version 14.0). Publication bias was evaluated using funnel plots and Egger's regression.

RESULTS

The meta-analysis incorporated 17 studies, encompassing 45,067,349 individuals with follow-up periods ranging from 0.5 to 2 years. The pooled analysis revealed no significant association between vaccinations and an increased risk of SLE [OR = 1.14, 95% CI (0.86-1.52), I2 = 78.1%, P = 0.348]. Subgroup analyses indicated that HBV vaccination was significantly associated with an elevated risk of SLE [OR =2.11, 95% CI (1.11-4.00), I2 = 63.3%, P = 0.02], HPV vaccination was slightly associated with an increased risk of SLE [OR = 1.43, 95% CI (0.88-2.31), I2 = 72.4%, P = 0.148], influenza vaccination showed no association with an increased risk of SLE [OR = 0.96, 95% CI (0.82-1.12), I2 = 0.0%, P = 0.559], and COVID-19 vaccine was marginally associated with a decreased risk of SLE [OR = 0.44, 95% CI (0.18-1.21), I2 = 91.3%, P = 0.118].

CONCLUSIONS

This study suggests that vaccinations are not linked to an increased risk of SLE. Our meta-analysis results provide valuable insights, alleviating concerns about SLE risk post-vaccination and supporting further vaccine development efforts.

Human papillomavirus vaccine initiation and up-to-date vaccine coverage for adolescents after the implementation of school-entry policy in Puerto Rico

The human papillomavirus (HPV) vaccine has been proven effective in the prevention of infection with high-risk HPV types, which can lead to the development of six HPV-related cancers. Puerto Rico (PR) adopted a mandatory HPV vaccination school-entry policy that took effect in August 2018. While school-entry requirements are generally accepted as an effective approach for increasing vaccination rates, there are few studies that have documented their impact on improving HPV vaccination rates. The objective of this study was to evaluate the impact of the HPV school-entry policy in PR on HPV vaccine coverage. We used a pre-post natural experiment. The study population included adolescents registered in the PR Immunization Registry during 2008-2019. We calculated HPV vaccine initiation and up-to-date (UTD) vaccine coverage rates. We estimated age-standardized rates (ASR) and standardized rate ratio with 95%CI. Vaccine data corresponding to a total of 495,327 adolescents were included for analysis; 50.9% were male and 49.1% were females. After policy implementation, a marked increase in raw HPV vaccine initiation among 11- to 12-year-old adolescents was observed across years 2017 (a pre-policy year), 2018, and 2019 (58.3%, 76.3%, and 89.8%, respectively). UTD coverage also showed a moderate increase after policy implementation among 11- to 12-year-old adolescents. The gap between sexes in vaccine initiation and UTD coverage narrowed over time; the ASRs in 2019 showed an increase of 19% in initiation and 7% increase in UTD relative to 2017 for males and females combined (both significant at p<0.05). This study demonstrated evidence of improvement in HPV vaccination rates following implementation of the school-entry policy and a narrowed sex gap in vaccine rates over time in PR. Future analyses should assess how the policy continues to affect vaccine coverage in subsequent years and how the COVID-19 pandemic has impacted HPV vaccination uptake.

Risk of Guillain-Barré syndrome after vaccination against human papillomavirus: a systematic review and meta-analysis, 1 January 2000 to 4 April 2020

BackgroundGuillain-Barré syndrome (GBS) is a rare autoimmune disease that can follow viral infections and has in a few cases been linked to vaccinations. Pre-licensure clinical trials did not observe an association between human papillomavirus (HPV) vaccination and GBS, a post-marketing study from 2017 reported an increased relative risk.AimWe assessed the risk of GBS after HPV vaccination through a systematic literature review and meta-analysis.MethodsWe searched Embase, MEDLINE and Cochrane for studies reporting on the risk of GBS after HPV vaccination in individuals aged ≥ 9 years, published between 1 January 2000 and 4 April 2020, excluding studies without a comparator group. Seven studies reporting relative effect sizes were pooled using random-effects meta-analysis. We assessed quality of evidence using the GRADE approach. Study protocol was registered (PROSPERO No. #CRD42019123533).ResultsOf 602 identified records, we included 25 studies. Based on over 10 million reports, cases of GBS were rare. In 22 studies no increased risk was observed, while in three studies a signal of increased risk of GBS after HPV vaccination was identified. Meta-analysis yielded a pooled random-effects ratio of 1.21 (95% CI: 0.60-2.43); I2 = 72% (95% CI: 36-88). This translates to a number needed to harm of one million to be vaccinated to generate one GBS case. Quality of evidence was very low.ConclusionsThe absolute and relative risk of GBS after HPV vaccination is very low and lacks statistical significance. This is reassuring for the already implemented vaccination programmes and should be used in respective communication activities.

Estimation of mid-and long-term benefits and hypothetical risk of Guillain-Barre syndrome after human papillomavirus vaccination among boys in France: A simulation study

BACKGROUND

The burden of human papillomavirus (HPV) infection can be substantially reduced through vaccination of girls, and gender-neutral policies are being adopted in many countries to accelerate disease control among women and expand direct benefits to men. Clinical direct benefit of boys HPV vaccination has been established for ano-genital warts and anal cancer. HPV vaccines are considered safe, but an association with Guillain-Barre syndrome has been found in French reimbursement and hospital discharge data.

METHODS

We conducted a Monte-Carlo simulation assuming a stable French population of 11- to 14-year-old boys, adult men and men having sex with men. We modelled and quantified the mid-term benefits as the annually prevented ano-genital warts among the 8.72 M men aged 15-35 years and the long-term benefits as the annually prevented anal cancer cases among the 17.4 M men aged 25-65 years. We also estimated the number of Guillain-Barre syndrome cases hypothetically induced by vaccination.

RESULTS

With a vaccine coverage of 30%, an annual number of 9310 (95% uncertainty interval [7050-11,200]) first ano-genital warts episodes among the 8.72 M men aged 15-35 years are prevented. According to more or less optimistic hypotheses on the proportion of HPV cancers covered by the vaccine, between 15.1 [11.7-17.7] and 19.2 [15.0-22.6] cases of anal cancer among the 17.4 M men aged 25-65 years would be annually avoided. Among men having sex with men, the corresponding figures were 1907 (1944-2291) for ano-genital warts and between 2.0 [0.23-4.5] and 2.6 [0.29-5.7] for anal cancer. Among 11- to 14-year-old boys, 0.82 (0.15-2.3) Guillain-Barre syndrome cases would be induced annually.

INTERPRETATION

A long-term program of HPV vaccination among boys in France would avoid substantially more cancer cases than hypothetically induce Guillain-Barre syndrome cases, in the general and specifically the homosexual population. Additional benefits may arise with the possible vaccine protection against oro-laryngeal and -pharyngeal cancer.

Moving from nature to nurture: a systematic review and meta-analysis of environmental factors associated with juvenile idiopathic arthritis

Objectives

JIA is the most common paediatric rheumatic disease, thought to be influenced by both genetics and the environment. Identifying environmental factors associated with disease risk will improve knowledge of disease mechanism and ultimately benefit patients. This review aimed to collate and synthesize the current evidence of environmental factors associated with JIA.

Methods

Four databases (MEDLINE, Embase, Web of Science and Cumulative Index to Nursing and Allied Health Literature) were searched from inception to January 2020. Study quality was rated using the Newcastle-Ottawa Scale. Pooled estimates for each environmental factor were generated using a random-effects, inverse-variance method, where possible. The remaining environmental factors were synthesized in narrative form.

Results

This review includes 66 environmental factors from 39 studies (11 cohort and 28 case-control studies) over 45 years. Study sample sizes ranged from 41 to 1.9 million participants. Eight environmental factors from ten studies were meta-analysed. Caesarean section delivery was associated with increased JIA risk [pooled odds ratio (OR) 1.11, 95% CI: 1.01, 1.22]. Conversely, presence (vs absence) of siblings (pooled OR 0.60, 95% CI: 0.44, 0.81) and maternal prenatal smoking (pooled OR 0.70, 95% CI: 0.58, 0.84) were associated with decreased JIA risk.

Conclusion

This review identifies several environmental factors associated with JIA and demonstrates the huge breadth of environmental research undertaken over five decades. We also highlight the challenges of combining data collected over this period due to limited between study comparability, evolution in healthcare and social practices, and changing environment, which warrant consideration when planning future studies.

Human papillomavirus vaccination and all-cause morbidity in adolescent girls: a cohort study of absence from school due to illness

Background

A growing body of evidence supports the safety of the human papillomavirus (HPV) vaccines. However, concerns about autonomic dysfunction syndromes and non-specific symptoms continue to linger. These conditions are not easily captured by traditional diagnostic classification schemes and call for innovative approaches to the study of vaccine safety which take more general measures of all-cause morbidity into account.

Methods

Taking advantage of the unique Danish registers, including regional registration of absence from school, we conducted a cohort study of 14 068 adolescent Danish girls attending 5th through 9th grade in public schools in the municipality of Copenhagen during 1 August 2013–23 January 2018. We obtained time-varying HPV vaccination status and demographic information from nationwide registers. Using Poisson regression with random effects, we estimated rate ratios (RRs) of absence due to illness, comparing HPV-vaccinated girls with unvaccinated girls with adjustment for grade, season, calendar period, demographic factors and random effects at the individual, class and school levels.

Results

Our study included 6 206 188 school days with 213 221 days of absence from school due to illness (absence rate, 3.4%). Comparing absence rates due to illness in HPV-vaccinated and unvaccinated girls yielded an adjusted RR of 1.00 (95% confidence interval [CI], 0.98–1.03).

Conclusions

Our study provides an important and novel contribution to HPV vaccine safety. Using absence from school records, we were able to address important safety concerns without relying on medical diagnoses. We conclude that HPV vaccination does not increase the risk of morbidity in any manner that manifests as absence from school due to illness.

Suitability of databases in the Asia-Pacific for collaborative monitoring of vaccine safety

INTRODUCTION

Information regarding availability of electronic healthcare databases in the Asia-Pacific region is critical for planning vaccine safety assessments particularly, as COVID-19 vaccines are introduced. This study aimed to identify data sources in the region, potentially suitable for vaccine safety surveillance. This manuscript is endorsed by the International Society for Pharmacoepidemiology (ISPE).

METHODS

Nineteen countries targeted for database reporting were identified using published country lists and review articles. Surveillance capacity was assessed using two surveys: a 9-item introductory survey and a 51-item full survey. Survey questions related to database characteristics, covariate and health outcome variables, vaccine exposure characteristics, access and governance, and dataset linkage capability. Other questions collated research/regulatory applications of the data and local publications detailing database use for research.

RESULTS

Eleven databases containing vaccine-specific information were identified across 8 countries. Databases were largely national in coverage (8/11, 73%), encompassed all ages (9/11, 82%) with population size from 1.4 to 52 million persons. Vaccine exposure information varied particularly for standardized vaccine codes (5/11, 46%), brand (7/11, 64%) and manufacturer (5/11, 46%). Outcome data were integrated with vaccine data in 6 (55%) databases and available via linkage in 5 (46%) databases. Data approval processes varied, impacting on timeliness of data access.

CONCLUSIONS

Variation in vaccine data availability, complexities in data access including, governance and data release approval procedures, together with requirement for data linkage for outcome information, all contribute to the challenges in building a distributed network for vaccine safety assessment in the Asia-Pacific and globally. Common data models (CDMs) may help expedite vaccine safety research across the region.

18F-FDG-PET brain imaging may highlight brain metabolic alterations in dysautonomic syndrome after human papilloma virus vaccination

AIM

The aim of this study was to evaluate brain glucose metabolism by means of [18F]-fluoro-deoxygluycose (F-FDG) PET in a group of patients presenting dysautonomic syndrome after human papilloma virus (HPV) immunization.

METHODS

Medical records of patients, referred to the 'Second Opinion Medical Consulting Network' Medical Centre (Modena, Italy) diagnosed with dysautonomic syndrome were searched. Inclusion criteria were presence in the medical history of adverse drug reactions following HPV vaccine; a Montreal Cognitive Assessment score <25 and good quality of a F-FDG-PET brain scan performed within 12 months from the diagnosis of dysautonomic syndrome. F-FDG-PET images of patients (HPV-group) were compared to a control group, matched for age and sex, using statistical parametric mapping (SPM).

RESULTS

The F-FDG-PET study was available for five female patients. The SPM-group analysis revealed significant hypometabolism (P < 0.05 false discovery rate corrected) in the right superior and medial temporal gyrus (Brodmann areas 22, 21) and insula (Brodmann area 13). At a threshold of P < 0.001 (uncorrected), further hypometabolic regions were revealed in the right superior temporal gyrus (Brodmann area 42) and caudate head and in the left superior temporal gyrus (Brodmann area 22), frontal subcallosal gyrus (Brodmann area 47) and insula (Brodmann area 13). Relative hypermetabolism (P = 0.001) was revealed in the right premotor cortex (Brodmann area 6).

CONCLUSION

This study revealed the possibility of altered brain glucose metabolism in subjects with dysautonomic syndrome post-immunization with HPV vaccine. These results could reinforce the hypothesis of a causal relationship between HPV vaccine, or some component included in the vaccine and the development of clinical manifestations.

Association between quadrivalent human papillomavirus vaccination and selected syndromes with autonomic dysfunction in Danish females: population based, self-controlled, case series analysis

OBJECTIVE

To evaluate the association between quadrivalent human papillomavirus vaccination and syndromes with autonomic dysfunction, such as chronic fatigue syndrome, complex regional pain syndrome, and postural orthostatic tachycardia syndrome.

DESIGN

Population-based self-controlled case series.

SETTING

Information on human papillomavirus vaccinations and selected syndromes with autonomic dysfunction (chronic fatigue syndrome, complex regional pain syndrome, and postural orthostatic tachycardia syndrome) identified using ICD-10 (international classification of diseases, revision 10) diagnostic codes from Danish nationwide registers.

PARTICIPANTS

869 patients with autonomic dysfunction syndromes from a cohort of 1 375 737 Danish born female participants aged 10 to 44 years during 2007-16.

MAIN OUTCOME MEASURES

Self-controlled case series rate ratios (95% confidence intervals) of the composite outcome of chronic fatigue syndrome, complex regional pain syndrome, and postural orthostatic tachycardia syndrome, adjusted for age and season, comparing female participants vaccinated and unvaccinated with the quadrivalent human papillomavirus vaccine. Chronic fatigue syndrome, complex regional pain syndrome, and postural orthostatic tachycardia syndrome were also considered separately in secondary analyses.

RESULTS

During 10 581 902 person years of follow-up, 869 female participants with syndromes of autonomic dysfunction (136 with chronic fatigue syndrome, 535 with complex regional pain syndrome, and 198 with postural orthostatic tachycardia syndrome) were identified. Quadrivalent human papillomavirus vaccination did not statistically significantly increase the rate of a composite outcome of all syndromes with autonomic dysfunction in a 365 day risk period following vaccination (rate ratio 0.99, 95% confidence interval 0.74 to 1.32) or the rate of any individual syndrome in the risk period (chronic fatigue syndrome (0.38, 0.13 to 1.09), complex regional pain syndrome (1.31, 0.91 to 1.90), or postural orthostatic tachycardia syndrome (0.86, 0.48 to 1.54)).

CONCLUSIONS

When vaccination is introduced, adverse events could occur in close temporal relation to the vaccine purely by chance. These results do not support a causal association between quadrivalent human papillomavirus vaccination and chronic fatigue syndrome, complex regional pain syndrome, or postural orthostatic tachycardia syndrome, either individually or as a composite outcome. An increased risk of up to 32% cannot be formally excluded, but the statistical power of the study suggests that a larger increase in the rate of any syndrome associated with vaccination is unlikely.

Human Papillomavirus Vaccination and Physical and Mental Health Complaints Among Female Students in Secondary Education Institutions in Denmark

BACKGROUND

Previous studies have not explored the effect of HPV vaccination on health status at a longer time interval. Similarly, self-reported physical and mental health in recipients of the HPV vaccine has not been studied.

OBJECTIVE

To evaluate whether HPV vaccination was associated with physical and mental health complaints among girls in secondary education institutions.

DESIGN

Prospective cohort study.

PARTICIPANTS

This study used data from girls aged 15-20 years who participated in the Danish National Youth Study (DNYS) 2014. Data on HPV vaccination was retrieved from the Danish Vaccination Register.

MAIN MEASURES

Participants were asked whether they had experienced headaches, stomachache, neck pain, menstrual cramps, sore throat, sadness, irritation, nervousness and sleep problems in the past 6 months.

KEY RESULTS

Of 41,333 girls, 39,145 (94.7%) received at least one dose of HPV vaccine. The most prevalent health complaint among the vaccinated and not vaccinated females was "been irritable" (88.2% and 88.4%, respectively). The lowest proportion of health complaints was stomachache (49.6% in vaccinated and in 50.4% in unvaccinated girls). Regression model, adjusted for socio-demographic characteristics and health behavior, showed that HPV vaccination was associated with a lower likelihood of reporting sore throat (odd ratio [OR] 0.86, 95% confidence interval [CI] 0.78-0.95) and being sad (OR 0.86, 95%CI 0.76-0.97). Similar results were observed when HPV vaccination status was analyzed according to the number of doses received.

CONCLUSION

We conclude that HPV vaccination was not associated with physical and mental health complaints among girls in secondary education institutions in Denmark after a median of 5.3 years since HPV vaccination.

Vaccination With Moderate Coverage Eradicates Oncogenic Human Papillomaviruses If a Gender-Neutral Strategy Is Applied

BACKGROUND

Human papillomavirus (HPV) vaccination of girls with very high (>90%) coverage has the potential to eradicate oncogenic HPVs, but such high coverage is hard to achieve. However, the herd effect (HE) depends both on the HPV type and the vaccination strategy.

METHODS

We randomized 33 Finnish communities into gender-neutral HPV16/18 vaccination, girls-only HPV16/18 vaccination, and hepatitis B virus vaccination arms. In 2007-2010, 11 662 of 20 513 of 40 852 of 39 420 resident boys/girls from 1992 to 1995 birth cohorts consented. In 2010-2014, cervicovaginal samples from vaccinated and unvaccinated girls at age 18.5 years were typed for HPV6/11/16/18/31/33/35/39/45/51/52/56/58/59/66/68. Vaccine efficacy for vaccinated girls, HE for unvaccinated girls, and the protective effectiveness (PE) for all girls were estimated. We extended the community-randomized trial results about vaccination strategy with mathematical modeling to assess HPV eradication.

RESULTS

The HE and PE estimates in the 1995 birth cohort for HPV18/31/33 were significant in the gender-neutral arm and 150% and 40% stronger than in the girls-only arm. Concordantly, HPV18/31/33 eradication was already predicted in adolescents/young adults in 20 years with 75% coverage of gender-neutral vaccination. With the 75% coverage, eventual HPV16 eradication was also predicted, but only with the gender-neutral strategy.

CONCLUSIONS

Gender-neutral vaccination is superior for eradication of oncogenic HPVs.

Hospital Records of Pain, Fatigue, or Circulatory Symptoms in Girls Exposed to Human Papillomavirus Vaccination: Cohort, Self-Controlled Case Series, and Population Time Trend Studies

Human papillomavirus (HPV) vaccination has been associated with subsequent diffuse symptoms in girls, reducing public confidence in the vaccine. We examined whether girls have nonspecific outcomes of HPV vaccination, using triangulation from cohort, self-controlled case series (SCCS), and population time trend analyses carried out in Denmark between 2000 and 2014. The study population consisted of 314,017 HPV-vaccinated girls and 314,017 age-matched HPV-unvaccinated girls (cohort analyses); 11,817 girls with hospital records (SCCS analyses); and 1,465,049 girls and boys (population time trend analyses). The main outcome measures were hospital records of pain, fatigue, or circulatory symptoms. The cohort study revealed no increased risk among HPV vaccine-exposed girls, with incidence rate ratios close to 1.0 for abdominal pain, nonspecific pain, headache, hypotension/syncope, tachycardia (including postural orthostatic tachycardia syndrome), and malaise/fatigue (including chronic fatigue syndrome). In the SCCS analyses, we observed no association between HPV vaccination and subsequent symptoms. In time trend analyses, we observed a steady increase in these hospital records in both girls and (HPV-unvaccinated) boys, with no relationship to the 2009 introduction of HPV vaccine to Denmark's vaccination program. This study, which had nationwide coverage, showed no evidence of a causal link between HPV vaccination and diffuse autonomic symptoms leading to hospital contact.

Systematic Review and Meta-analysis of Postlicensure Observational Studies on Human Papillomavirus Vaccination and Autoimmune and Other Rare Adverse Events

BACKGROUND

Because of the limited number of subjects in prelicensure studies, autoimmune diseases and other rare adverse effects of vaccines may go undetected. Since 2006, millions of human papillomavirus (HPV) vaccine doses have been distributed and a considerable amount of postlicensure safety data has been generated. The objective of this study was to review available HPV postlicensure safety studies and to summarize risk estimates of autoimmune and other rare diseases.

METHODS

For this systematic review and meta-analysis, we searched literature databases to identify any postlicensure safety studies related to HPV vaccination and autoimmune adverse events from inception to April 16, 2019. Pooled risk estimates were computed using fixed- or random-effects models if at least 2 estimates per disease and per HPV vaccine were available.

RESULTS

Twenty-two studies met our inclusion criteria. The studies applied various methodologies and used different types of data sources and outcome definitions. Quadrivalent HPV vaccine (4vHPV) was most commonly assessed. Type 1 diabetes mellitus, immune thrombocytopenia purpura and thyroiditis diseases were most frequently reported. The meta-analysis was conducted on 35 diseases corresponding to 48 pooled risk estimates. Majority of the pooled estimates showed no significant effect (n = 43). Three negative (paralysis, immune thrombocytopenia purpura and chronic fatigue syndrome) and 2 positive (Hashimoto and Raynaud diseases) associations were detected.

CONCLUSION

Our study demonstrated an absence of clear association between HPV vaccines and autoimmune and other rare diseases. The review also highlights the need for more systematic collaborations to monitor rare safety adverse events.

Vaccine Safety: Myths and Misinformation

The World Health Organization has named vaccine hesitancy as one of the top ten threats to global health in 2019. The reasons why people choose not to vaccinate are complex, but lack of confidence in vaccine safety, driven by concerns about adverse events, has been identified as one of the key factors. Healthcare workers, especially those in primary care, remain key influencers on vaccine decisions. It is important, therefore, that they be supported by having easy access to trusted, evidence-based information on vaccines. Although parents and patients have a number of concerns about vaccine safety, among the most common are fears that adjuvants like aluminum, preservatives like mercury, inactivating agents like formaldehyde, manufacturing residuals like human or animal DNA fragments, and simply the sheer number of vaccines might be overwhelming, weakening or perturbing the immune system. As a consequence, some fear that vaccines are causing autism, diabetes, developmental delays, hyperactivity, and attention-deficit disorders, amongst others. In this review we will address several of these topics and highlight the robust body of scientific evidence that refutes common concerns about vaccine safety.

The science of vaccine safety: Summary of meeting at Wellcome Trust

Vaccines are everywhere hugely successful but are also under attack. The reason for the latter is the perception by some people that vaccines are unsafe. However that may be, vaccine safety, life any other scientific subject, must be constantly studied. It was from this point of view that a meeting was organized at the Wellcome Trust in London in May 2019 to assess some aspects of vaccine safety as subjects for scientific study. The objective of the meeting was to assess what is known beyond reasonable doubt and conversely what areas need additional studies. Although the meeting could not cover all aspects of vaccine safety science, many of the most important issues were addressed by a group of about 30 experts to determine what is already known and what additional studies are merited to assess the safety of the vaccines currently in use. The meeting began with reviews of the current situation in different parts of the world, followed by reviews of specific controversial areas, including the incidence of certain conditions after vaccination and the safety of certain vaccine components. Lastly, information about the human papillomavirus vaccine was considered because its safety has been particularly challenged by vaccine opponents. The following is a summary of the meeting findings. In addition to this summary, the meeting organizers will explore opportunities to perform studies that would enlarge knowledge of vaccine safety.

Safety of the AS04-adjuvanted human papillomavirus (HPV)-16/18 vaccine in adolescents aged 12-15 years: end-of-study results from a community-randomized study up to 6.5 years

This manuscript discloses end-of-study safety data of a community-randomized controlled trial in Finland (NCT00534638), assessing the effectiveness of two vaccination strategies (gender-neutral versus females only) using the AS04-adjuvanted human papillomavirus (HPV)-16/18 (AS04-HPV-16/18) vaccine. The total vaccination cohort included 32,175 adolescents aged 12–15 y at vaccination of whom 14,837 received the AS04-HPV-16/18 vaccine and 17,338 received the hepatitis-B virus vaccine (control). Spontaneous reporting of serious adverse events (SAEs) combined with surveillance using nation-wide health registries showed an acceptable safety profile of the AS04-HPV-16/18 vaccine. During the study period (up to 6.5 y), the incidences (per 100,000 person-years) of reported SAEs considered as possibly related to vaccination were 39.1 (95% confidence interval [CI]: 25.3–57.7) and 39.8 (95%CI: 26.8–56.8) in the HPV and control groups, respectively. The most frequently reported new-onset autoimmune diseases (NOADs) were ulcerative colitis (incidence rates of 28.2 and 33.1 per 100,000 person-years in the HPV and control groups, respectively), insulin-dependent diabetes mellitus (21.9 and 37.1), Crohn’s disease (15.6 and 22.5), celiac disease (15.6 and 21.2), and juvenile idiopathic arthritis (14.1 and 15.9). Of 1,344 pregnancies reported (777 and 567 in the HPV and control groups, respectively), most resulted in elective termination (58.4% and 58.6%), birth of a live infant (32.7% and 32.3%), or in spontaneous abortion (8.0% and 7.9%). No major, registered congenital anomalies were identified. The incidence rates of NOADs and pregnancy outcomes were generally balanced between groups. No specific safety signals were identified in the population-based health registry surveillance.

Plain Language Summary

What is the context?

● Since first licensure in 2007 of the AS04-adjuvanted human papillomavirus (HPV)-16/18 vaccine (Cervarix, GSK), large quantity of safety data has been collected and confirmed its safety profile. This study provides further unique, population-based safety data from vaccinated Finnish adolescents monitored via health registries up to 6.5 y of follow-up.

What is new?

● The vaccine has shown an acceptable safety profile in girls and boys. The risk of new-onset autoimmune diseases (NOADs) was similar between the HPV vaccine group and the control group and in line with the expectations for the studied population.

● The study supports that safety surveillance via national health registries is in general more sensitive than the conventional safety reporting, notably for monitoring specific chronic diseases, e.g. autoimmune disorders.

What is the impact?

● This study highlights the importance of health registries in long-term vaccination safety surveillance. The population-based safety data reported in this study further support the routine administration of the HPV vaccine to girls and boys.

Human papillomavirus (HPV) vaccine and autonomic disorders: a position statement from the American Autonomic Society

INTRODUCTION

Human papillomavirus (HPV) vaccination has been anecdotally connected to the development of dysautonomia, chronic fatigue, complex regional pain syndrome and postural tachycardia syndrome.

OBJECTIVES

To critically evaluate a potential connection between HPV vaccination and the above-noted conditions.

METHODS

We reviewed the literature containing the biology of the virus, pathophysiology of infection, epidemiology of associated cancers, indications of HPV vaccination, safety surveillance data and published reports linking HPV vaccination to autonomic disorders.

RESULTS

At this time, the American Autonomic Society finds that there are no data to support a causal relationship between HPV vaccination and CRPS, chronic fatigue, and postural tachycardia syndrome to other forms of dysautonomia.

CONCLUSION

Certain conditions are prevalent in the same populations that are vaccinated with the HPV vaccine (peri-pubertal males and females). This association, however, is an insufficient proof of causality.

Ten years of HPV vaccination in the Netherlands: current evidence and future challenges in HPV-related disease prevention

INTRODUCTION

Girls-only vaccination against human papillomavirus (HPV) type 16 and 18 was implemented in the Netherlands in 2009. Despite the evidence of the efficacy against precancerous lesions, cross-protection induced by the vaccine and a greater potential for cancer prevention than cervical cancer only, vaccine coverage in the girls-only program has remained below target levels.

AREAS COVERED

In this paper, we review the literature from the Netherlands on the effectiveness and cost-effectiveness of HPV vaccination since vaccine introduction, give an account of the coverage, safety and effectiveness of HPV vaccination as has been reported in the Dutch surveillance program and discuss challenges of the current HPV vaccination program.

EXPERT COMMENTARY

Girls-only HPV vaccination may confer a substantial health gain in HPV-related disease prevention. However, vaccine coverage declined remarkably recently possibly related to safety concerns, limiting the benefits from girls' vaccination and increasing the potential additional benefit of sex-neutral HPV vaccination. Considering the emergence of novel vaccination and screening options and the change from cytology- to HPV-based screening in 2017, further research is required to inform decisions on the optimization of an integrated vaccination and screening program.