No association between HPV vaccine and reported post-vaccination symptoms in Japanese young women: Results of the Nagoya study

Bivalent Human Papillomavirus Vaccine Effectiveness in a Japanese Population: High Vaccine-Type-Specific Effectiveness and Evidence of Cross-Protection

Background

Proactive recommendations for human papillomavirus (HPV) vaccines in Japan have been suspended for 5 years because of safety concerns. While no scientific evidence exists to substantiate these concerns, one reason given for not reinstating recommendations is the lack of reliable vaccine effectiveness (VE) data in a Japanese population. This study reports the VE of the bivalent HPV vaccine in Japanese women aged 20–22 years.

Methods

During cervical screening between 2014 and 2016, women had Papanicolaou smears and HPV tests performed and provided data about their sexual history. Estimates of VE for vaccine-targeted HPV type 16 (HPV16) and 18 and cross-protection against other types were calculated.

Results

Overall, 2197 women were tested, and 1814 were included in the analysis. Of these, 1355 (74.6%) were vaccinated, and 1295 (95.5%) completed the 3-dose schedule. In women sexually naive at vaccination, the pooled VEs against HPV16 and 18 and for HPV31, 45, and 52 were 95.5% (P < .01) and 71.9% (P < .01), respectively. When adjusted for number of sex partners and birth year, pooled VEs were 93.9% (P = .01) and 67.7% (P = .01) for HPV16 and 18 and HPV31, 45, and 52, respectively.

Conclusions

The bivalent HPV vaccine is highly effective against HPV16 and 18. Furthermore, significant cross-protection against HPV31, 45, and 52 was demonstrated and sustained up to 6 years after vaccination. These findings should reassure politicians about the VE of bivalent HPV vaccine in a Japanese population.

Reduction in HPV16/18 prevalence among young women with high-grade cervical lesions following the Japanese HPV vaccination program

The Japanese government began a human papillomavirus (HPV) vaccination program for girls aged 12‐16 years in 2010 but withdrew its recommendation in 2013 because of potential adverse effects, leading to drastically reduced vaccination uptake. To evaluate population‐level effects of HPV vaccination, women younger than 40 years of age newly diagnosed with cervical intraepithelial neoplasia grade 1‐3 (CIN1‐3), adenocarcinoma in situ (AIS), or invasive cervical cancer (ICC) have been registered at 21 participating institutes each year since 2012. A total of 7709 women were registered during 2012‐2017, of which 5045 were HPV genotyped. Declining trends in prevalence of vaccine types HPV16 and HPV18 during a 6‐year period were observed in CIN1 (50.0% to 0.0%, P_trend < .0001) and CIN2‐3/AIS (83.3% to 45.0%, P_trend = .07) only among women younger than 25 years of age. Overall, HPV vaccination reduced the proportion of HPV16/18‐attributable CIN2‐3/AIS from 47.7% to 33.0% (P = .003): from 43.5% to 12.5% as routine vaccination (P = .08) and from 47.8% to 36.7% as catch‐up vaccination (P = .04). The HPV16/18 prevalence in CIN2‐3/AIS cases was significantly reduced among female individuals who received their first vaccination at age 20 years or younger (P = .02). We could not evaluate vaccination effects on ICC owing to low incidence of ICC among women aged less than 25 years. We found HPV vaccination to be effective in protecting against HPV16/18‐positive CIN/AIS in Japan; however, our data did not support catch‐up vaccination for women older than 20 years. Older adolescents who skipped routine vaccination due to the government’s suspension of its vaccine recommendation could benefit from receiving catch‐up vaccination before age 20 years.

Stopping the HPV vaccine crisis in Japan: Quantifying the benefits and risks of HPV vaccination in quality-adjusted life-years for appropriate decision-making

BACKGROUND

The human papilloma virus (HPV) vaccination coverage rate in Japan has dropped dramatically from more than 70% to less than 1% since 2013. With conflicting information and a lack of quantification of the benefits and risks of the HPV vaccine, parents have been hindered in making their decision. We quantified the benefits and risks of the HPV vaccine in terms of quality-adjusted life-years (QALYs), to help their informed decision.

METHOD

A literature search was performed to determine the incidence and burden of each outcome in a decision tree model. The benefits and the risks of the HPV vaccination were determined in QALY change with a sensitivity analysis.

RESULT

The benefits of the HPV vaccine in terms of QALYs gained were 703.72, 14.45, and 30.83/100,000 persons for cervical cancer, cervical intraepithelial neoplasm 3 (CIN 3), and genital warts, respectively. The QALY loss due to acute adverse reactions, chronic adverse reactions without assistance needs, and chronic adverse reactions with assistance needs were 0.07, 5.83, and 5.82/100,000 persons, respectively. The risk/benefit ratio in QALY change in the base case was 0.0156. In all scenarios, the benefit of the HPV vaccine was significantly greater than the risk.

CONCLUSION

The benefits are much greater than the risks, even if it is assumed that all reported adverse events were due to the vaccination. The Japanese government and health care providers should immediately recommend the HPV vaccine to all adolescent girls irrespective of any causal links between the vaccine and reported adverse events.

Bodily distress syndrome after receiving vaccines: A case report

A 48-year-old woman presented with various symptoms, including widespread body pains, insomnia, palpitations, and shortness of breath, after receiving tetanus toxoid. After going through multiple visits to clinicians of various subspecialties, she was referred to our infectious diseases clinic. She was diagnosed with bodily distress syndrome (BDS), possibly triggered by tetanus toxoid injection. Her symptoms improved shortly after reassurance and medical management. Functional disorders such as BDS can occur after vaccinations, and one must be aware of this possibility in patients with multiple symptoms after receiving vaccines.

Autonomic dysfunction and HPV immunization: an overview

This article reviews the case series reported from several countries describing patients with suspected severe side effects to the HPV vaccines. The described symptom clusters are remarkably similar and include disabling fatigue, headache, widespread pain, fainting, gastrointestinal dysmotility, limb weakness, memory impairment episodes of altered awareness, and abnormal movements. This constellation of symptoms and signs has been labeled with different diagnoses such as complex regional pain syndrome (CRPS), postural orthostatic tachycardia syndrome (POTS), small fiber neuropathy (SFN), myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), or fibromyalgia. It is known that autoimmunity and autoantibodies are present in a subset of patients with CRPS, POTS, SFN, ME/CFS, and fibromyalgia. This article proposes that vaccine-triggered, immune-mediated autonomic dysfunction could lead to the development of de novo post-HPV vaccination syndrome possibly in genetically susceptible individuals. Being cognizant that a temporal relationship between vaccination and symptom onset does not necessarily equate to causality, mounting evidence of case series calls for well-designed case-control studies to determine the prevalence and possible causation between these symptom clusters and HPV vaccines. Since personalized medicine is gaining momentum, the use of adversomics and pharmacogenetics may eventually help identify individuals who are predisposed to HPV vaccine adverse events.

Human papillomavirus (HPV) vaccination: from clinical studies to immunization programs

Cervical cancer incidence and mortality have decreased in high-income countries, but low- and middle-income countries continue to bear a significant burden from the disease. Human papillomavirus (HPV) vaccines are a promising alternative for disease control; however, their introduction is slow in settings with greater need. We conducted a review of HPV vaccine efficacy and effectiveness reported in clinical trials and population-based studies. Efficacy of HPV vaccines is close to 100% when using a three-dose schedule in HPV-negative young women (<25 years old) for protection against persistent infection and HPV vaccine-type associated pre-cancerous lesions. Furthermore, sustained protection for up to 12 years of follow-up has been demonstrated; cross-protection against non-vaccine types is particularly observed for the bivalent vaccine, and preliminary data regarding impact on invasive cancer have emerged. Given its lower efficacy, catch-up vaccination beyond 19 years of age and proposals for vaccinating adult women deserve careful evaluation in accurately designed studies and economic analyses. Despite positive results regarding immunogenicity and post-hoc analysis for cervical intra-epithelial neoplasia in clinical trials, population-based data for prime and booster two-dose schedules are not available. Evaluation of vaccine safety from surveillance systems in immunization programs that have already distributed more than 270 million doses found no association of HPV vaccination with serious side effects. The introduction of HPV vaccination in national immunization programs remains the main challenge in tackling the burden of cervical cancer (up to 2018, only 89 countries have introduced vaccination worldwide, and most of these are high-income countries). Access models and technical capacity require further development to help low- and middle-income countries to increase the pace of vaccine delivery. Alternative approaches such as one-dose schedules and vaccination at younger ages may help reduce the programmatic and economic challenges to adolescent vaccination.

Current knowledge of and attitudes toward human papillomavirus-related disease prevention among Japanese: A large-scale questionnaire study

AIM

The human papillomavirus (HPV) vaccination rate in Japan fell to nearly 0% following widespread coverage of possible adverse events. Developing a next approach to promote the effective prevention of HPV-related diseases including cervical cancer (CC) in Japan requires comprehensive understanding of knowledge and attitudes regarding CC prevention, HPV infection and HPV vaccination among the population including laypersons and medical professions in Japan.

METHODS

A questionnaire survey was administered in a wide variety of settings in Japan. The questionnaire contained items on knowledge about CC, HPV infection and HPV vaccination; awareness of the HPV vaccine's effectiveness and associated adverse events; and attitudes toward the HPV vaccination for their daughters and for men/boys.

RESULTS

Of 3033 targeted people, complete survey responses were received from 1182 men and 1602 women (total: 2784). The male laypersons' group had significantly lower knowledge than did the female laypersons' group (adjusted odds ratio, aOR = 3.86, P < 0.001). Compared with the male laypersons' group, the female laypersons' group tended to have less positive attitudes toward HPV vaccination for their daughters (aOR = 0.78, P = 0.006), but the female laypersons' group showed more positive attitudes toward vaccinating men/boys (aOR = 1.93, P < 0.001).

CONCLUSION

The survey results indicated that men in Japan generally lacked knowledge and awareness of HPV-related diseases and their prevention. However, women had more negative attitudes toward HPV vaccination for their daughters than did men. Increasing male involvement in HPV prevention and changing women's perceptions of the HPV vaccine are essential steps to increase the HPV vaccination rate.

Safety concerns with human papilloma virus immunization in Japan: Analysis and evaluation of Nagoya City's surveillance data for adverse events

Aim

To assess the safety of human papilloma virus (HPV) vaccines by using data from the “Nagoya City Cervical Cancer Immunization Program Survey”.

Methods

Unadjusted odds ratios (OR) were calculated between HPV‐vaccinated cases and un‐vaccinated controls. Age‐stratified analyses were performed to evaluate the interaction between age and events. Adjusted ORs were also estimated with multiple logistic regression models.

Results

In the 15–16‐year‐old group, the unadjusted ORs were significantly higher for symptoms of memory impairment, dyscalculia, and involuntary movement. The age‐adjusted multivariate analyses demonstrated that the vaccinated cases were less likely than the unvaccinated controls to have experienced symptoms in almost all symptoms, except for two symptoms such as involuntary movement and weakness. However, study period‐adjusted multivariate analyses demonstrated that the vaccinated cases were significantly more likely than un‐vaccinated controls to have experienced symptoms of memory impairment and involuntary movement.

Conclusions

Based on our analysis using data from the Nagoya City surveillance survey, a possible association between HPV vaccination and distinct symptoms such as cognitive impairment or movement disorders exists. A consistent causal relationship between HPV vaccination and these symptoms remains uncertain. However, given the seriousness of symptoms, we believe that a more comprehensive and large‐scale study is essential to confirm the safety of HPV vaccination.

Effectiveness of HPV vaccination against high grade cervical lesions in Japan

The effectiveness of HPV vaccine against HSIL+ (pathologically diagnosed CIN2+) in the first cohort in Japan was investigated in 22,743 women aged 20 to 29 years (parts of national cervical cancer screening program of FY [fiscal year] 2015, the Japan Cancer Society). Vaccinated women had a statistically significant 69% lower risk of HSIL+ as compared to the unvaccinated women; the crude relative risk estimate was 0.31 (95% CI: 0.11-0.83; p-value = 0.013) by normal approximation and 0.31 (95% CI: 0.08-0.80; p-value = 0.009) by the exact Poisson regression. The effect of age was not significant (chisq = 7.7 (df = 9), p-value = 0.569) and the estimate of relative risk remained essentially intact after adjustment for age. This study brings scientific evidence on the effectiveness of HPV vaccine on development of cervical high grade lesions.

A Review of HPV-Related Head and Neck Cancer

Head and neck squamous cell carcinomas (HNSCCs) arise in the mucosal lining of the upper aerodigestive tract. Tobacco and alcohol use have been reported to be associated with HNSCC. Infection with high-risk human papillomaviruses (HPVs) has recently been implicated in the pathogenesis of HNSCCs. It is now widely accepted that high-risk HPV is a cause of almost all cervical cancers as well as some forms of HNSCCs. HPV-related HNSCCs are increasing. HPV-related HNSCCs and HPV-unrelated HNSCCs differ with respect to the molecular mechanisms underlying their oncogenic processes. HPV-related HNSCCs are known to have a better prognosis response to treatment as compared with HPV-unrelated HNSCCs. Therefore, in recent years, it has been required to accurately discriminate between HPV-related and HPV-unrelated HNSCCs. To diagnose the HPV-related HNSCCs, various methods including P16 immunohistochemistry, FISH, and genetic analyses of the HPV gene from histopathological and liquid biopsy specimens have been employed. Based on the results of the differential diagnosis, various treatments employing EGFR TKI and low-dose radiation have been employed. Here, we review the involvement of the HPV virus in HNSCCs as well as the molecular mechanism of carcinogenesis, classification, prognosis, diagnostic procedures, and therapy of the disease.

Progress and challenges for the Japanese immunization program: Beyond the "vaccine gap"

The Japanese immunization program has made considerable recent progress. The introduction of several new vaccines, especially foreign-produced vaccines, and the inclusion of important new vaccines in the National Immunization Program (NIP) are closing the "vaccine gap", i.e., the delay in the Japanese immunization program relative to programs in other developed countries. Major progress in the Japanese immunization program since 2014 includes (1) elimination of measles in March 2015, (2) introduction of a varicella vaccine as a routine immunization in the NIP in October 2015, and (3) introduction of hepatitis B virus vaccines as routine immunizations in the NIP in October 2016. Despite these promising developments, important issues remain. First, the government withdrew the active recommendation for human papilloma virus vaccines temporarily in 2013. The withdrawal has continued and unresolved despite new scientific evidence confirming the safety of these vaccines. Second, a few important voluntary vaccines, including vaccines for mumps and rotavirus, have not been included in the NIP since their introduction to Japan. Finally, there are concerns related to a shortage of mandatory domestic vaccines, which was caused by a natural disaster in the area where a vaccine-producing factory was located. Additionally, the manufacturer included unauthorized additives in some vaccine products with falsifying the production-process records. To avoid problems related to vaccine shortages, essential vaccines need to be stockpiled, and the future vaccine needs for children should to be discussed. New initiatives must continue to close the vaccine gap, as this will protect children living in Japan from vaccine-preventable diseases.