Safety of Human Papillomavirus Vaccines: A Review

Adverse events from HPV vaccination in Taiwan

The safety of human papillomavirus (HPV) vaccines has been evaluated continuously in pre-licensure clinical trials, post-marketing surveillance systems, and observational studies. Most studies have found no significant association between serious adverse events and HPV vaccination. However, these studies have focused on Western populations; similar studies focusing on Asian populations are insufficient. Our retrospective cohort study used the HPV-vaccination records of junior high-school adolescent girls aged 12-15 years between 2013 and 2018 in Taiwan's National Immunization Information System and linked them to a registry for beneficiaries in Taiwan's National Health Insurance Database (NHID) to establish the vaccinated group. We selected 19 serious diseases as serious adverse events. We compared the incidence rates of these serious adverse events between the vaccinated group and girls in the same age group population, and we calculated the standardized incidence ratio (SIR) to evaluate the risk of serious adverse events after HPV vaccination. Because of the onset of different types of diseases, we set three periods after the subjects received HPV vaccination: within 3 months, within 1 year, and during the study period (2013-2018). The results showed the incidence rates and the SIRs of 19 selected adverse events. Among the 19 selected serious adverse events, the disease with the highest incidence rate during the study period was fibromyalgia (73.23 cases per million population), and the disease with the lowest incidence rate during the study period was Crohn's disease (0.15 cases per million population). The results showed no statistically significant increases in the risk of 19 selected serious adverse events and indicated no association between HPV vaccination and serious adverse events. Given the benefits and safety of HPV vaccination, our research can reduce concerns about vaccine side effects, inform health policies and improve public and clinician's acceptance of HPV vaccine policy.

Can human papillomavirus vaccination during pregnancy result in miscarriage and stillbirth? A meta-analysis and systematic review

INTRODUCTION

Contradictory results regarding the safety of human papillomavirus (HPV) vaccination during pregnancy have been obtained, which has cast doubt on the use of this method. This review and meta-analysis were conducted to evaluate the safety of HPV vaccination during pregnancy.

METHODS

Complying with the inclusion and exclusion criteria, we searched Web of Science, Scopus, Medline, EMBASE, PubMed and Google Scholar databases for articles published in the past decade using the following keywords: 'papilloma human virus', 'HPV vaccine', 'pregnancy' and 'safety and prevention'. The minimum report quality of the articles was 16 based on the STROBE checklist.

RESULTS

Seven articles were included in the study, three of which were included in the meta-analysis, and the rest were reviewed systematically. The results of the meta-analysis showed that vaccination against HPV during pregnancy or around this period does not increase the risk of miscarriage (RR=2.01; 95% CI: 0.66-6.13) and stillbirth (RR=2.02: 95% CI: 0.65-6.27). No significant difference between miscarriage and stillbirth was observed in women vaccinated against HPV versus those not vaccinated.

CONCLUSIONS

The study of 1380424 individuals showed that HPV vaccination during pregnancy is better postponed until after this period. However, no significant evidence was found to indicate that vaccination was dangerous and unsafe during pregnancy. Further studies are needed to draw a more definitive conclusion.

Virus-like Particles as Antiviral Vaccine: Mechanism, Design, and Application

Virus-like particles (VLPs) are viral structural protein that are noninfectious as they do not contain viral genetic materials. They are safe and effective immune stimulators and play important roles in vaccine development because of their intrinsic immunogenicity to induce cellular and humoral immune responses. In the design of antiviral vaccine, VLPs based vaccines are appealing multifunctional candidates with the advantages such as self-assembling nanoscaled structures, repetitive surface epitopes, ease of genetic and chemical modifications, versatility as antigen presenting platforms, intrinsic immunogenicity, higher safety profile in comparison with live-attenuated vaccines and inactivated vaccines. In this review, we discuss the mechanism of VLPs vaccine inducing cellular and humoral immune responses. We outline the impact of size, shape, surface charge, antigen presentation, genetic and chemical modification, and expression systems when constructing effective VLPs based vaccines. Recent applications of antiviral VLPs vaccines and their clinical trials are summarized.

Prophylactic and Therapeutic HPV Vaccines: Current Scenario and Perspectives

Persistent human papillomavirus (HPV) infection is recognized as the main cause of cervical cancer and other malignant cancers. Although early detection and treatment can be achieved by effective HPV screening methods and surgical procedures, the disease load has not been adequately mitigated yet, especially in the underdeveloped areas. Vaccine, being regarded as a more effective solution, is expected to prevent virus infection and the consequent diseases in the phases of both prevention and treatment. Currently, there are three licensed prophylactic vaccines for L1-VLPs, namely bivalent, quadrivalent and nonavalent vaccine. About 90% of HPV infections have been effectively prevented with the implementation of vaccines worldwide. However, no significant therapeutic effect has been observed on the already existed infections and lesions. Therapeutic vaccine designed for oncoprotein E6/E7 activates cellular immunity rather than focuses on neutralizing antibodies, which is considered as an ideal immune method to eliminate infection. In this review, we elaborate on the classification, mechanism, and clinical effects of HPV vaccines for disease prevention and treatment, in order to make improvements to the current situation of HPV vaccines by provoking new ideas.

Immunogenicity and safety of a bivalent, adjuvant system 04-adjuvanted human papillomavirus vaccine in healthy female volunteers aged 15-25: a randomized, double-blind, phase III, noninferiority clinical trial

OBJECTIVE

Vaccination is proven to significantly reduce the risk of human papillomavirus (HPV)-related complications, especially cervical cancer. This study aimed to assess the immunogenicity and safety of the investigational bivalent HPV vaccine (16/18), named Papilloguard (Noyan Pajouhan Biopharma, Tehran, Iran), in comparison with the reference product (Cervarix, bivalent HPV vaccine (16/18) manufactured by GlaxoSmithKline, Rixensart, Belgium) in a three-dose regimen.

METHODS

This trial was a randomized, controlled, double-blind, phase III study of two HPV vaccines in healthy female volunteers aged 15-25. The primary endpoint was to test the noninferiority of Papilloguard (Noyan Pajouhan Biopharma) to Cervarix (GlaxoSmithKline) as measured by the geometric mean titer (GMT) ratios of HPV-16 and HPV-18 7 months after the first vaccination. Secondary endpoints were the proportion of local and systemic solicited and unsolicited events, and the number of females with seroconversion against HPV-16 and HPV-18 7 months after the first vaccination.

RESULTS

Out of 504 screened women, 218 were enrolled. Seven months after the first vaccination, GMT ratios of HPV-16 and HPV-18 were 0.59 and 0.93, respectively. The seroconversion rates of both Papilloguard (Noyan Pajouhan Biopharma) and Cervarix (GlaxoSmithKline) were more than 96%. Both vaccinated groups had a generally good profile of solicited and unsolicited adverse events (AEs). The most common AE was discomfort at the injection site, which was well tolerated.

CONCLUSION

The result analysis of this study supports the noninferiority of Papilloguard (Noyan Pajouhan Biopharma) to Cervarix (GlaxoSmithKline) in terms of safety and immunogenicity based on the GMT ratio. However, long-term comparative studies to evaluate the sustainability of GMT response and risk of cervical intraepithelial neoplasia grades 2-3 are needed.

Human Papillomavirus Vaccine Hesitancy Highly Evident among Caregivers of Girls Attending South African Private Schools

The viral spread of social media misinformation and disinformation regarding human papillomavirus (HPV) vaccination safety has resulted in widespread vaccine hesitancy and suboptimal HPV vaccination uptake. We previously reported that only 19.4% of age-eligible private school girls in South Africa in 2018 had received ≥1 HPV vaccine dose. Here, we report on reasons given by caregivers for why their daughters were unvaccinated. An online survey targeting caregivers of girls in grades 4–7 attending South African private schools was conducted. Caregivers of unvaccinated girls provided the most important reason for their daughter not being vaccinated by either selecting from a list of coded reasons or providing a free text reason. Free text reasons were analysed, coded and added to the list of coded reasons, which were categorised according to broad themes. Frequency distributions of reasons and categories were calculated. Most reasons were related to vaccine hesitancy (61.4%), followed by lack of access to the vaccine (21.3%) and lack of information (15.7%). HPV vaccination coverage among age-eligible girls can be improved by including private-sector schools in the South African HPV vaccination programme, training healthcare providers to advocate for HPV vaccination and extending HPV vaccination advocacy campaigns to include private-sector educators.

Analgesic and adjuvant properties of exercise with vaccinations in healthy young population

Introduction: Exercise holds the potential to be beneficial if used during vaccination processes by 1)exercise-induced analgesia to reduce pain associated with vaccination, 2)immune-enhancing effects, improving antibody responses to the vaccine, and 3)reducing local and systemic adverse reactions to the vaccine. This study examines whether analgesic responses could be enhanced locally in the exercising limb to further benefit the use of exercise during influenza vaccination processes to minimize vaccine-related pain and improve antibody response to inactivated influenza vaccines.Methods: 57 participants (22.6 ± 3.2 years, 33 females) randomized into a control (n = 19) or one of two exercise groups: pre-vaccine arm (n = 19) or pre-vaccine leg (n = 19). Intervention groups performed exercise (15 minutes), prior to administration of the vaccine. Vaccine-related pain and pressure pain threshold (PPT) were measured at baseline and post-vaccination for all groups. Blood samples were taken on the day of vaccination and one month later to measure serum antibody titers to influenza.Results: No significant difference in vaccine-related pain or change in PPT was found with exercise, however, there was a trend in higher reports of vaccine-related pain in females compared to males(p = .06). Significantly higher fold increase (p = .02) of the B/Brisbane/60/2008 strain was found in the exercise group compared to the control group.Conclusion: The current study failed to observe an analgesic effect of exercise to improve vaccine-related pain in young adults. However, immune-enhancing effects in one of four strains suggest potential adjuvant effects of exercise. Importantly, the sex difference in pain sensitivity suggests the need for separate analysis, especially when examining pain perception.Australian New Zealand Clinical Trial Registry (ACTRN:12617000374369).

Vaccination against HPV: boosting coverage and tackling misinformation

The availability of human papillomavirus (HPV) vaccines and screening tests has raised the possibility of globally eliminating cervical cancer, which is caused by HPV. Cervical cancer is a very common malignancy worldwide, especially among deprived women. High vaccination coverage is key to the containment and eventual elimination of the infection. Public HPV vaccination programmes in Italy and Denmark were swiftly established and are among the most successful worldwide. Still, in both countries, it has been challenging to achieve and maintain the recommended coverage of > 80% in girls. In a well-studied Italian region, vaccination coverage in girls at age 15 years (World Health Organization's gold standard) reached 76% in 2015 but decreased to 69% in 2018, likely due to work overload in public immunization centres. In Denmark, doubts about safety and efficacy of the HPV vaccine generated a decline in coverage among girls age 12-17, from 80% in 2013 down to 37% in 2015, when remedial actions made it rise again. Insights from these two countries are shared to illustrate the importance of monitoring coverage in a digital vaccine registry and promptly reacting to misinformation about vaccination.

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 development of dysautonomia, chronic fatigue, complex regional pain syndrome and postural tachycardia syndrome.

OBJECTIVES

To critically evaluate a potential connection between HPV vaccination and 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, POTS or other forms of dysautonomia.

CONCLUSIONS

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

From the Infection to the Immunotherapy in Cervical Cancer: Can We Stop the Natural Course of the Disease?

Cervical cancer (CC) is the second leading cause of cancer death in women aged 20–39 years. Persistent infection with oncogenic types of human papillomavirus (HPV) represents the most important risk factor for the development of cervical cancer. Three HPVs vaccines are currently on the global market: bivalent, quadrivalent, and nonavalent. The nonavalent vaccine provides protection against almost 90% of HPV-related CC. Despite availability of primary and secondary prevention measures, CC persists as one of the most common cancers among women around the world. Although CC is a largely preventable disease, management of persistent or recurrent CC no longer amenable to control with surgery or radiation therapy has not improved significantly with the progress of modern chemotherapy and disseminated carcinoma of the cervix remains a discouraging clinical entity with a 1-year survival rate between 10% and 15%. Over the last few years, there has been increasing interest in immunotherapy as a strategy to fight tumors. This article focuses on recent discoveries about the HPV vaccine and immunotherapies in the prevention and treatment of CC, highlighting the future view.

Scientific evidence supporting recommendations on the use of the 9-valent HPV vaccine in a 2-dose vaccine schedule in Australia

The Australian Technical Advisory Group on Immunisation (ATAGI) updated recommendations on the use of human papillomavirus (HPV) vaccines in the Australian Immunisation Handbook in 2018, regarding the use of the recently available 9-valent (9vHPV) vaccine, Gardasil 9, and a 2-dose schedule for young adolescents for HPV vaccines. This report provides an overview of the relevant scientific evidence that underpinned these updated recommendations. The 9vHPV vaccine includes 5 HPV types (HPV 31, 33, 45, 52 and 58) additional to the 4 that are also covered by the 4vHPV (Gardasil) vaccine (HPV 6,11,16,18). Accordingly, the 9vHPV vaccine is expected to prevent an additional 15% of cervical cancers and up to 20% of other HPV-related cancers. Non-inferior antibody responses after two 9vHPV vaccine doses given 6-12 months apart in girls and boys aged 9-14 years compared to women aged 16-26 years after three doses support the 2-dose schedule for adolescents of this age group. In clinical trials 9vHPV vaccine was well-tolerated with a similar safety profile to 4vHPV vaccine. The switch to 9vHPV vaccine and a 2-dose schedule is anticipated to improve public acceptability of the program and reduce HPV-related disease in the long-term.

Summary of the evidence on the safety, efficacy, and effectiveness of human papillomavirus vaccines: Umbrella review of systematic reviews

BACKGROUND

This objective of this umbrella review was to summarize the evidence on safety, efficacy, and effectiveness of human papillomavirus (HPV) vaccines in the general population.

METHODS

The authors conducted a literature search and selected systematic reviews if they were published from January 2006 through November 2018, included randomized controlled trials or observational studies, related to the general population, and evaluated HPV vaccine-related clinical outcomes. The authors independently and in duplicate screened literature, extracted data, and appraised reviews using AMSTAR 2, a critical appraisal tool for systematic reviews.

RESULTS

The authors selected 30 systematic reviews that included male and female participants aged 9 through 76 years from multiple countries. Reviews evaluated postvaccine seroconversion, HPV infection rates, precancerous or benign lesions, and adverse events; none of the researchers reported on oral or oropharyngeal lesions. Results from the reviews showed that, compared with those who received a placebo or non-HPV-type vaccine, HPV-vaccinated participants had statistically significantly higher rates of seroconversion and local adverse events, statistically significantly lower rates of HPV infection and condylomata lesions, and decreased rates of HPV-related precancerous lesions, which did not always attain statistical significance.

CONCLUSIONS

Systematic reviews have found evidence that the available HPV vaccines are safe, effective, and efficacious against vaccine-type HPV infection and HPV-associated cellular changes, including precancerous and benign lesions.

PRACTICAL IMPLICATIONS

Dentists may use this resource to better understand the literature on the potential harms and benefits of HPV vaccination.

[HPV vaccination: not only female adolescents and not only prophylactic. Review and position paper of the Italian HPV Study Group (IHSG)]

HPV vaccination has been introduced in clinical practice in recent years and represents the most effective strategy of primary prevention of cervical carcinoma and of female genital preneoplastic conditions. One of the major issues of the subject is represented by vaccination coverage of the target population. Since its introduction, HPV vaccine efficacy has been progressively demonstrated also towards extragenital HPV-correlated conditions and in males too. Moreover, even subjects of older age groups or subjects who already had HPV infections have been demonstrated to received benefits from vaccination, due to improvements of their immunological response. Recently, vaccine efficacy has also been investigated in terms of adjuvant administration after treatments of preneoplastic or benign conditions of the female lower genital tract caused by HPVs; preliminary results indicate an interesting and promising field of application. On this basis, in this article an analysis of the state of the art has been performed, with specific regard to the Italian scenario and with the focus of future perspectives of implementation of the HPV vaccination policy. From the available evidences, the Italian HPV Study Group recommends the extension of systematic HPV vaccination to males too, to adult subjects and also after conservative treatment of genital HPV correlated conditions.

Facilitators and barriers of human papillomavirus vaccine uptake in young females 18-26 years old in Singapore: A qualitative study

BACKGROUND

Around 70% of cervical cancers are caused by Types 16 and 18 of human papillomavirus (HPV). Vaccines against HPV have been shown to be safe and effective in preventing HPV and cervical cancer.

OBJECTIVE

To explore the facilitators and barriers of HPV vaccination in young females aged 18-26 years in Singapore, and to describe their recommended strategies to improve the uptake of HPV vaccination.

DESIGN

Qualitative, descriptive design guided by the socio-ecological model.

PARTICIPANTS

Young women studying in National University of Singapore (NUS), aged 18-26 (N = 40). Purposive sampling was used to recruit participants from various socio-economic levels and faculties, both vaccinated against HPV and unvaccinated.

METHODS

In-depth interviews (IDIs) and focus group discussions (FGDs) were conducted with the participants. IDIs and FGDs were transcribed and coded using NVIVO software. Thematic data analysis was performed using an inductive approach.

RESULTS

Barriers to HPV vaccination included lack of awareness, lack of perceived risk for cervical cancer, cost, lack of parental support, inconvenience of getting the vaccination, stigma associated with connection with sexual activity, and concern regarding safety. Facilitators include parental encouragement, protection of one's health, lack of logistical barriers, and perceived safety and efficacy of the vaccine. Participants recommended increasing awareness of HPV vaccination and cervical cancer, reducing cost of vaccination and making the vaccine compulsory to increase vaccine uptake.

CONCLUSION

Barriers and facilitators exist at different levels to influence vaccine uptake. Public education on cervical cancer and the vaccine should be stepped up to increase public awareness. A school-based national vaccination programme was proposed by the target group to increase the rate of uptake of HPV vaccination in Singapore.

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.

Incorporation of CD40 ligand or granulocyte-macrophage colony stimulating factor into Hantaan virus (HTNV) virus-like particles significantly enhances the long-term immunity potency against HTNV infection

PURPOSE

Hantavirus infections cause severe haemorrhagic fever with renal syndrome (HFRS) in humans and are associated with high fatality rates. In 2017, numerous outbreaks were reported in China and Germany. This represents a significant public-healthcare issue with no effective HFRS vaccines that offer a long-term immune response. In this study, we investigated the long-term humoral and cellular immune responses and protective immunity of Hantaan virus (HTNV) granulocyte-macrophage colony stimulating factor (GM-CSF) and CD40 ligand (CD40L) virus-like particles (VLPs) in mice.

METHODOLOGY

GM-CSF and CD40L VLPs were constructed via co-transfection of pCI-S and pCI-M-CD40L, and pCI-S and pCI-M-GM-CSF, into dihydrofolatereductase (dhfr)-deficient Chinese hamster ovary cells, respectively. Mice were immunized with HTNV VLPs 2 weeks apart. The animals were challenged 6 months after immunization. Specific and neutralizing antibodies were assessed by ELISA; IFN-γ was measured by enzyme-linked immunospot (ELISpot) assay and effectiveness by cytotoxic T lymphocyte (CTL) cytotoxicity assays. Nucleic acid loads of HTNV were tested by quantitative real-time PCR and viral antigen was detected via indirect ELISA. Pathological alterations were detected via haematoxylin-eosin staining.

RESULTS

GM-CSF and CD40L VLPs provided stable, long-term protection with a high titre of neutralizing antibody in mice 6 months after immunization. Furthermore, VLPs increased HTNV-specific cellular immune responses via higher expression of IFN-γ and CTL responses. HTNV challenge assay results showed long-term protection against HFRS. No significant pathological alteration was observed in the organs of mice after immunization.

CONCLUSION

This is, to the best of our knowledge, the first report demonstrating the long-term potency of HTNV VLP vaccines against HTNV infection and offers new insights into HTNV vaccine development.

Development of an Intervention to Reduce Pain and Prevent Syncope Related to Adolescent Vaccination

INTRODUCTION

There is a lack of research into the perspectives of patients, parents, and clinicians regarding strategies for vaccine-related pain and syncope prevention that may improve the adolescent vaccination experience and encourage future vaccination.

OBJECTIVE

To develop an intervention on the basis of preference for strategies to reduce pain and prevent syncope associated with adolescent vaccination.

METHODS

We conducted focus groups and interviews with 8 recently vaccinated Kaiser Permanente Northwest (KPNW) members aged 11 to 17 years and their parents to explore perceptions of pain and syncope after vaccination as well as receptivity to potential interventions. Additionally, we interviewed 7 clinical staff who routinely vaccinate children. We conducted content analysis to identify promising interventions and conducted a data synthesis workshop to select a final intervention for piloting.

RESULTS

All participants expressed willingness to use previsit education, breathing exercises, social support or distraction, and water consumption. Patients and parents expressed a need for verbal education and messaging about potential vaccine-related outcomes, and clinicians noted a need to identify patients who are anxious before a vaccination visit. Most participants suggested a "comfort menu" intervention, to include comfort and distraction items that medical staff offer adolescents before and during vaccination.

CONCLUSION

Patients, parents, and clinicians acknowledged the value of interventions to reduce pain and syncope after adolescent vaccination. Stakeholders identified a comfort menu as the intervention to be piloted at 2 KPNW pediatric clinics. Further research is needed to test the effectiveness of the "Vaccination Comfort Menu" intervention in improving vaccination experiences and continued receipt of vaccinations.

Predictors of cervical cancer screening among Kenyan women: results of a nested case-control study in a nationally representative survey

BACKGROUND

Cervical cancer is a major public health concern in Kenya. It is the leading cause of cancer morbidity and mortality among women. Although screening is an effective prevention method, uptake is low among eligible women. Little is known about predictors of cervical cancer screening uptake. This study explored relationship between uptake of cervical cancer screening, socio-demographic, behavioral and biological risk factors.

METHODS

Nested case-control study within STEPS survey, a population-based cross-sectional household survey conducted between April and June 2015.Cases were women who had undergone cervical cancer screening and controls were unscreened women. Study participants were women eligible for cervical cancer screening (30-49 years). Variables included socio-demographic; behavioral risk factors such as physical activity, tobacco and alcohol use diet and biological factors like diabetes and hypertension. Outcome of interest was cervical cancer screening. Data analysis was done using STATA version 14. Logistic regression model was used to assess relationship between cervical cancer screening and socio-demographic, behavioral and biological risk factors.

RESULTS

Of 1180 women interviewed, 16.4% (n = 194) had been screened for cervical cancer. Of unscreened women (n = 986), 67.9% were aware of cervical cancer screening. Higher screening rates were observed in more educated women (25.2%), highest income quintile (29.6%) and living in urban areas (23%) than in women with no formal education (3.2%), poorest (3.6%) and living in rural areas (13.8%). Younger women (35-39) and those with low High-density lipoprotein (HDL) were less likely to be screened [OR = 0.56; 95% CI = (0.34, 0.93); p-value = 0.025] and [OR = 0.51; 95% CI = (0.29, 0.91); p = value 0.023] respectively. Self-employed women, those in the fourth wealth quintile, binge drinkers, high sugar consumption and insufficient physical activity were more likely to be screened [OR 2.55 (1.12, 5.81) p value 0.026], [OR 3.56 (1.37, 9.28) p value 0.009], [OR 5.94 (1.52, 23.15) p value 0.010], [OR 2.99 (1.51, 5.89) p value 0.002] and [OR 2.79 (1.37, 5.68) p value 0.005] respectively.

CONCLUSION

Uptake of cervical cancer screening is low despite high awareness. Strategies to improve cervical cancer screening in Kenya should be implemented with messages targeting persons with both risky and non-risky lifestyles especially younger women with no formal education living in rural areas.

Safety of Human Papillomavirus Vaccines: An Updated Review

Human papillomavirus (HPV) vaccines are now included in immunisation programmes in 71 countries. Unfortunately, uptake has been impacted in some countries by reduced confidence in the safety of the HPV vaccine. In 2013, we published an extensive review demonstrating a reassuring safety profile for bivalent (2vHPV) and quadrivalent (4vHPV) vaccines. A nonavalent (9vHPV) vaccine is now available and HPV immunisation programmes have been extended to males in 11 countries. The aim of this updated narrative review was to examine the evidence on HPV vaccine safety, focusing on the 9vHPV vaccine, special populations and adverse events of special interest (AESI). The previous searches were replicated to identify studies to August 2016, including additional search terms for AESI. We identified 109 studies, including 15 population-based studies in over 2.5 million vaccinated individuals across six countries. All vaccines demonstrated an acceptable safety profile; injection-site reactions were slightly more common for 9vHPV vaccine than for 4vHPV vaccine. There was no consistent evidence of an increased risk of any AESI, including demyelinating syndromes or neurological conditions such as complex regional pain or postural orthostatic tachycardia syndromes. The risk-benefit profile for HPV vaccines remains highly favourable.

Risk of human papillomavirus infection in women with rheumatic disease: cervical cancer screening and prevention

Human Papillomavirus (HPV) is the most common sexually transmitted infection in the USA, with over 14 million people acquiring HPV each year. HPV is also the cause of most anogenital cancers. About 90% of HPV infections spontaneously resolve over 3 years. However, about 10% remain as persistent infection defined as repeatedly detected in cervical samples. As HPV is controlled by local and systemic immune responses, individuals with immunosuppression are at risk for cervical cancer. It is hypothesized that immunosuppressed individuals are more likely to have HPV persistence, which is necessary for malignant transformation. Accordingly, women with rheumatic diseases such as SLE and RA are likely vulnerable to HPV infection and the progression of cervical disease. The HPV vaccine, given as a series of vaccinations, is safe and effective that can prevent HPV infection and cervical cancer. There is no contraindication to HPV vaccination for women to age 26 with rheumatic disease, as it is not live. As in the general population, timing is key for the efficacy of the HPV vaccine as the goal is to vaccinate prior to sexual debut and exposure to HPV. There are no formal recommendations for cervical cancer screening in women with rheumatic disease but recommendations for the HIV-positive population can be adopted, meaning to screen with a Pap test annually for three consecutive years and if all normal, to extend the interval to every 3 years with the option of co-testing with HPV at 30 years and older.

Recommendations for cervical cancer prevention and control in Ghana: public education and human papillomavirus vaccination

Globally, cervical cancer is a major public health issue causing increasing morbidity and mortality especially in low- and middle-income countries where preventive and control measures are lacking. In Ghana, it is the most common cancer among women. Approaches to reduce the incidence and mortality of the disease in Ghana have had little success due to lack of accurate data on the disease among other factors, to inform policies on prevention, early detection, diagnosis and treatment. Additionally, the lack of clear commitment, policy direction and resources has hindered the scale-up of some of the initiatives implemented to curb the cervical cancer situation in Ghana. In this paper, we make recommendations on cervical cancer education and human papillomavirus vaccination. A collaborative approach is needed involving both private and government organizations, health professionals and the general public. Public education on cervical cancer and HPV vaccination needs to be delivered through a mixture of systems including both healthcare facilities and outreach programs, involving teachers, youth groups, community members and professional bodies. The vaccination of adolescents aged 10-14 years using the nonavalent HPV vaccine will be important in reducing the incidence and mortality of cervical cancer in Ghana. The integration of public education on cervical cancer prevention, HPV vaccination and screening programs into both medical and public health services is critical in achieving high coverage of these programs.

FUNDING

None.

Human papillomavirus vaccination of adult women and risk of autoimmune and neurological diseases

BACKGROUND

Since 2006, human papillomavirus (HPV) vaccines have been introduced in many countries worldwide. Whilst safety studies have been reassuring, focus has been on the primary target group, the young adolescent girls. However, it is also important to evaluate safety in adult women where background disease rates and safety issues could differ significantly.

OBJECTIVE

We took advantage of the unique Danish and Swedish nationwide healthcare registers to conduct a cohort study comparing incidence rate ratios (RRs) of 45 preselected serious chronic diseases in quadrivalent HPV (qHPV)-vaccinated and qHPV-unvaccinated adult women 18-44 years of age.

METHODS

We used Poisson regression to estimate RRs according to qHPV vaccination status with two-sided 95% confidence intervals (95% CIs).

RESULTS

The study cohort comprised 3 126 790 women (1 195 865 [38%] Danish and 1 930 925 [62%] Swedish) followed for 16 386 459 person-years. Vaccine uptake of at least one dose of qHPV vaccine was 8% in the cohort: 18% amongst Danish women and 2% amongst Swedish. We identified seven adverse events with statistically significant increased risks following vaccination-Hashimoto's thyroiditis, coeliac disease, localized lupus erythematosus, pemphigus vulgaris, Addison's disease, Raynaud's disease and other encephalitis, myelitis or encephalomyelitis. After taking multiple testing into account and conducting self-controlled case series analyses, coeliac disease (RR 1.56 [95% confidence interval 1.29-1.89]) was the only remaining association.

CONCLUSION

Unmasking of conditions at vaccination visits is a plausible explanation for the increased risk associated with qHPV in this study because coeliac disease is underdiagnosed in Scandinavian populations. In conclusion, our study of serious adverse event rates in qHPV-vaccinated and qHPV-unvaccinated adult women 18-44 years of age did not raise any safety issues of concern.

Association between Human Papilloma Virus (HPV) vaccination and risk of Multiple Sclerosis: A systematic review

INTRODUCTION

The vaccination against Humanpapilloma Virus (HPV) is an effective strategy to prevent high-risk HPV infection and subsequent cervical carcinogenesis. Although the safety profile has been ascertained, the relation with the development of central nervous system (CNS) autoimmune disorders (AD) appears still controversial. Multiple Sclerosis (MS) is the most common cause of chronic neurological impairment in young people, typically striking females. The main purpose of this review was to assess the association between HPV vaccination and MS.

METHODS

The systematic review of the literature was carried out using 5 search engines: MEDLINE, SCOPUS, ISI WEB OF KNOWLEDGE, GOOGLE SCHOLAR and ClinicalTrial.gov. The web search was updated on January 2017. PRISMA checklist was adopted to address the content of the systematic review. The measures of outcome were reported as relative risk (RR) in cohort studies and odds ratio (OR) in case-control studies.

RESULTS

The systematic review identified 5 observational studies, 9 reviews, and 1 randomized clinical trials (RCT) pooled analysis. The RR of MS onset detected by cohort studies ranged from 1.54 (95%CI, 0.04-8.59) to 1.37 (95%CI, 0.74-3.20). Concerning case-control studies, the OR spanned from 0.3, (95%CI 0.1-0.9) to 1.60 (95%CI = 0.79-3.25) for the group exposed to HPV vaccination. No result was significant.

CONCLUSION

This review showed no significant association between HPV vaccination and MS. The low statistical power of the studies agreed with the low incidence of MS disease among general population. In order to overcome the shortcoming the research may be extended to the entire pattern of CNS ADs.

Diverse Families' Experiences with HPV Vaccine Information Sources: A Community-Based Participatory Approach

Current sources of publicly available human papillomavirus (HPV) information may not adequately meet the needs of diverse families. This study sought to describe associations between sociodemographic and acculturation factors, and sources of HPV information among diverse parents and caregivers. Community organizations purposively recruited participants from African American, African refugee, Hispanic/Latino, American Indian, and Native Hawaiian and Pacific Islander communities for a 21-item survey (N = 228). Ninenty-three of these participants also participated in ten focus groups conducted in three languages. Descriptive statistics and Fishers' Exact Test for Count Data were produced and triangulated with focus group data to provide additional context. Overall, HPV vaccine awareness and knowledge in the five communities was low. This study found that a greater proportion of lower-acculturated participants had heard of HPV through personal networks (foreign-born = 50 % vs US-born = 30 %, p < 0.05; medium acculturation = 60 % vs high acculturation = 26 %, p = 0.01), while greater proportions of US-born participants reported media sources (49 % vs foreign-born = 29 %, p < 0.05). Across communities, healthcare system sources were described as important and preferred sources of HPV information. Hearing about the HPV vaccine from healthcare settings was significantly associated with increased accuracy in HPV vaccine knowledge (p < 0.05). Communities described a need for more in-depth information about the HPV vaccine, and culturally and linguistically appropriate educational materials. Culturally-competent delivery of HPV information through the healthcare system sources may be important in improving knowledge and acceptability of the HPV vaccine among diverse families.

Drinking Water to Prevent Postvaccination Presyncope in Adolescents: A Randomized Trial

BACKGROUND AND OBJECTIVES

Postvaccination syncope can cause injury. Drinking water prephlebotomy increases peripheral vascular tone, decreasing risk of blood-donation presyncope and syncope. This study evaluated whether drinking water prevaccination reduces postvaccination presyncope, a potential syncope precursor.

METHODS

We conducted a randomized trial of subjects aged 11 to 21 years receiving ≥1 intramuscular vaccine in primary care clinics. Intervention subjects were encouraged to drink 500 mL of water, with vaccination recommended 10 to 60 minutes later. Control subjects received usual care. Presyncope symptoms were assessed with a 12-item survey during the 20-minutes postvaccination. Symptoms were classified with a primary cutoff sensitive for presyncope, and a secondary, more restrictive cutoff requiring greater symptoms. Results were adjusted for clustering by recruitment center.

RESULTS

There were 906 subjects randomly assigned to the control group and 901 subjects randomly assigned to the intervention group. None had syncope. Presyncope occurred in 36.2% of subjects by using the primary definition, and in 8.0% of subjects by using the restrictive definition. There were no significant differences in presyncope by intervention group for the primary (1-sided test, P = .24) or restrictive outcome (1-sided test, P = .17). Among intervention subjects vaccinated within 10 to 60 minutes after drinking all 500 mL of water (n = 519), no reduction in presyncope was observed for the primary or restrictive outcome (1-sided tests, P = .13, P = .17). In multivariable regression analysis, presyncope was associated with younger age, history of passing out or nearly passing out after a shot or blood draw, prevaccination anxiety, receiving >1 injected vaccine, and greater postvaccination pain.

CONCLUSIONS

Drinking water before vaccination did not prevent postvaccination presyncope. Predictors of postvaccination presyncope suggest opportunities for presyncope and syncope prevention interventions.

9-Valent human papillomavirus vaccine: a review of the clinical development program

INTRODUCTION

The 9-valent human papillomavirus (9vHPV) vaccine covers the same HPV types (6/11/16/18) as the quadrivalent HPV (qHPV) vaccine and 5 additional cancer-causing types (31/33/45/52/58). Epidemiological studies indicate that the 9vHPV vaccine could prevent approximately 90% of cervical cancers, 70-85% of high-grade cervical dysplasia (precancers), 85-95% of HPV-related vulvar, vaginal, and anal cancers, and 90% of genital warts. Areas covered: Study design features and key findings from the 9vHPV vaccine clinical development program are reviewed. In particular, 9vHPV vaccine efficacy was established in a Phase III study in young women age 16-26 years. Efficacy results in young women were extrapolated to pre- and young adolescent girls and boys and young men by immunological bridging (i.e., demonstration of non-inferior immunogenicity in these groups versus young women). Expert commentary: The development of the 9vHPV vaccine is the outcome of 20 years of continuous clinical research. Broad vaccination programs could help substantially decrease the incidence of HPV-related disease.

Cervical Cancer Prevention Through HPV Vaccination in Low- and Middle-Income Countries in Asia

Cervical cancer is ranked the first or second most common cancer in women of low- and middle-income countries (LMICs) in Asia. Cervical cancer is almost exclusively caused by human papillomavirus (HPV), and majority of the cases can be prevented with the use of HPV vaccines. The HPV vaccines have demonstrated high vaccine efficacies against HPV infection and cervical cancer precursors in clinical and post-marketing studies, and are in use in most high-income countries. However, their use in LMICs are limited mainly due to the high costs and logistics in delivering multiple doses of the vaccine. Other issues such as the safety of the vaccines, social and cultural factors, as well as poor knowledge and awareness of the virus have also contributed to the low uptake of the vaccine. This mini-review focuses on the need for HPV vaccine implementation in Asia given the substantial disease burden and underuse of HPV vaccines in LMICs in this region. In addition, the progress towards HPV vaccine introduction, and barriers preventing further rollout of these essential, life-saving vaccines are also discussed in this article.

Population-based HPV vaccination programmes are safe and effective: 2017 update and the impetus for achieving better global coverage

Persistent oncogenic human papillomavirus (HPV) is the cause of cervical cancer, as well as cancers of the anus, penis, vulva, vagina and oropharynx. There is good evidence that prophylactic HPV vaccines are immunogenic and effective against targeted-type HPV infections and type-specific genital lesions, including high-grade cervical intraepithelial neoplasia (CIN), when administered prior to HPV infection. There is good evidence that HPV vaccines are safe in population usage, with the most frequent adverse event being injection-site reactions. There is evidence to support some cross-protection against non-targeted types occurring following the administration of HPV vaccines. There is limited evidence suggesting that HPV vaccines may be beneficial in preventing future disease in women treated for high-grade CIN. This chapter focuses on the accumulated evidence regarding the global use of the three licensed HPV vaccines including safety, immunogenicity, duration of protection, effectiveness, coverage to date and barriers to higher coverage.

Major findings and recent advances in virus-like particle (VLP)-based vaccines

Virus-like particles (VLPs) have made giant strides in the field of vaccinology over the last three decades. VLPs constitute versatile tools in vaccine development due to their favourable immunological characteristics such as their size, repetitive surface geometry, ability to induce both innate and adaptive immune responses as well as being safe templates with favourable economics. Several VLP-based vaccines are commercially available including vaccines against Human Papilloma Virus (HPV) such as Cervarix^®, Gardasil^® & Gardasil9^® and Hepatitis B Virus (HBV) including the 3rd generation Sci-B-Vac™. In addition, the first licensed malaria-VLP-based vaccine Mosquirix™ has been recently approved by the European regulators. Several other VLP-based vaccines are currently undergoing preclinical and clinical development. This review summarizes some of the major findings and recent advances in VLP-based vaccine development and technologies and outlines general principles that may be harnessed for induction of targeted immune responses.

Human papillomavirus first and second generation vaccines-current status and future directions

It has been more than 10 years that the first prophylactic papillomavirus vaccine became available, although distribution has been mainly limited to the more affluent countries. The first two vaccines have been a great success, hundreds of millions of women and a much smaller number of men have been vaccinated ever since. In a few countries with high vaccination coverage, in particular Australia but also parts of Great Britain and others, clinical impact of vaccination programs is already visible and there are indications for herd immunity as well. Vaccine efficacy is higher than originally estimated and the vaccines have an excellent safety profile. Gardasil9 is a second generation HPV virus-like particle vaccine that was licensed in 2015 and there are more to come in the near future. Currently, burning questions in respect to HPV vaccination are the duration of protection - especially in regard to cross-protection - reduction of the three-dose regimen and its impact on cross-protection; and duration of response, as well as protection against oropharyngeal HPV infections. Furthermore, researchers are seeking to overcome limitations of the VLP vaccines, namely low thermal stability, cost, invasive administration, limited coverage of non-vaccine HPV types, and lack of therapeutic efficacy. In this review we summarize the current status of licensed VLP vaccines and address questions related to second and third generation HPV vaccines.

Human papillomavirus vaccination and risk of autoimmune diseases: A large cohort study of over 2million young girls in France

BACKGROUND

Whether human papillomavirus (HPV) vaccination could induce or trigger autoimmune diseases (AID) has been questioned, and potentially contributes to low immunization coverage in France. This study evaluated the association between HPV vaccination and the risk of AID using routinely collected data sources.

METHODS

All girls aged 13-16years between 2008 and 2012, covered by the general health insurance scheme and without history of HPV vaccination or AID, were included and followed using French nationwide databases. Fourteen neurological, rheumatological, haematological, gastrointestinal or endocrine AID, were identified from ICD-10 codes allocated to hospital stays and long-term illnesses or by marker drugs. Their incidence was compared between girls exposed and non-exposed to HPV vaccination, using a Cox model adjusted for inclusion year, geographic area, socio-economic indicators, healthcare use level and other immunizations.

RESULTS

Among 2,252,716 girls, 37% received HPV vaccine and 4,096 AID occurred during a mean follow-up time of 33months. The incidence of AID was not increased after exposure to HPV vaccination, except for Guillain-Barré syndrome (GBS) (incidence rate of 1.4 among exposed [20 cases] versus 0.4 per 100,000 PY among unexposed [23 cases]; adjusted HR: 3.78 [1.79-7.98]). This association persisted across numerous sensitivity analyses and was particularly marked in the first months following vaccination. Under the hypothesis of a causal relationship, this would result in 1-2 GBS cases attributable to HPV vaccine per 100,000 girls vaccinated.

CONCLUSIONS

Our study provides reassuring results regarding the risk of AID after HPV vaccination, but an apparently increased risk of GBS was detected. Further studies are warranted to confirm this finding.

Vaccination and autoimmune diseases: is prevention of adverse health effects on the horizon?

Autoimmune diseases, including multiple sclerosis and type 1 diabetes mellitus, affect about 5% of the worldwide population. In the last decade, reports have accumulated on various autoimmune disorders, such as idiopathic thrombocytopenia purpura, myopericarditis, primary ovarian failure, and systemic lupus erythematosus (SLE), following vaccination. In this review, we discuss the possible underlying mechanisms of autoimmune reactions following vaccinations and review cases of autoimmune diseases that have been correlated with vaccination. Molecular mimicry and bystander activation are reported as possible mechanisms by which vaccines can cause autoimmune reactions. The individuals who might be susceptible to develop these reactions could be especially not only those with previous post-vaccination phenomena and those with allergies but also in individuals who are prone to develop autoimmune diseases, such as those with a family history of autoimmunity or with known autoantibodies, and the genetic predisposed individuals. Further research is encouraged into the direct associations between vaccines and autoimmune conditions, and the biological mechanisms behind them.

Evaluation of optic neuritis following human papillomavirus vaccination

To assess the relationship between human papillomavirus (HPV) vaccination and occurrence of optic neuritis (ON) and to evaluate a claims-based algorithm for identification of ON. Females of 9-26 year olds in the HealthCore's Integrated Research Database (HIRDSM) with and without claims evidence of HPV vaccination between 2007 and 2012 were included in this study. Potential ON cases were identified using the claims-based algorithm, positive predictive value (PPV) was determined using medical chart review. For the claims analysis, two study designs, a self-controlled temporal scan statistic and a retrospective matched cohort analysis, were used. ON was defined based on an algorithm developed using diagnosis and procedure codes from the medical claims. The PPV for ON cases using charts that had enough information for reviewers to make a determination was 62.5% (95% CI: 49.5%-74.3%). With the self-controlled temporal scan statistic, the primary analysis restricting on recommended vaccination schedule timing showed an increased risk of potential ON after second dose (RR = 3.39; p = 0.03), this finding was not confirmed for any of the additional analyses performed for individual or combined doses. With the cohort design, there was no increased risk of potential ON following vaccination in either individual or combined dose analyses. The risk of potential ON was higher among participants with a history of prior autoimmune diseases. In conclusion, identifying confirmed ON cases through administrative claims data proved challenging. The claims-based analysis in this study did not provide evidence for an association of ON with HPV vaccination.

Incidence rates of Guillain Barré (GBS), chronic fatigue/systemic exertion intolerance disease (CFS/SEID) and postural orthostatic tachycardia syndrome (POTS) prior to introduction of human papilloma virus (HPV) vaccination among adolescent girls in Finland, 2002-2012

BACKGROUND

In Finland a vaccination programme against human papillomavirus (HPV) was introduced in November 2013 for girls aged 11-12 years with a catchup for girls 13-15 years. Allegations that HPV vaccine is causing Guillain Barré syndrome (GBS) and non-specific diagnostic entities, such as chronic fatigue syndrome/systemic exertion intolerance disease (CFS/SEID) and postural orthostatic tachycardia syndrome (POTS), continue to surface. We examined population register-based incidence rates of CFS/SEID, GBS and POTS to provide baseline data for future HPV vaccine safety evaluations.

METHODS

First diagnosis of CFS/SEID, GBS and POTS in girls aged 11-15 years were obtained from the National Hospital Discharge Register during 2002-2012. We considered the following ICD-10 codes: G93.3 for CFS; G61.0 for GBS and G90.9, G90.8, G93.3, I49.8 for POTS. We calculated incidence rates per 100,000 person-years with 95% confidence intervals (CI).

RESULTS

In total, 9 CFS/SEID, 19 GBS and 72 POTS cases were identified. The overall incidence rate was 0.53/100,000 (95% CI; 0.27-1.01) for CFS/SEID, 1.11 (95% CI; 0.71-1.74) for GBS and 4.21 (95%CI; 3.34-5.30) for POTS. Significant relative increase in annual incidence rate with a peak in 2012 was observed in CFS/SEID (33% (95% CI; 3.0-70.3: p=0.029) and POTS (16.5% (95% CI; 7.8-25.9: p<0.05), but not in GBS (5.4% (95% CI; -8.4-21.3: p=0.460).

CONCLUSIONS

Our findings provide baseline estimates of CFS/SEID, GBS and POTS incidences in Finland. However, rates based on register data should be interpreted with caution, especially for non-specific diagnostic entities for which internationally and even nationally agreed criteria are still being discussed. To assess the associations with HPV vaccine, methods using register linkage for cohort and self-controlled case series should be explored in addition to factors contributing to patients seeking care, treating physicians setting the diagnoses, and their preference of using of codes for these clinical entities.

Cervical cancer, human papillomavirus and vaccines: assessment of the information retrieved from general knowledge websites in Chile

OBJECTIVES

Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth cause of cancer death in Chile. Human papillomavirus (HPV) is responsible for most cervical cancers. Individuals seeking basic information about HPV frequently turn to health information websites. We hypothesized that some of their data may be inaccurate.

STUDY DESIGN

Comparative analysis of information.

METHODS

We analyze the content of highly accessed websites such as the Spanish version of Wikipedia and Yahoo Answers through the application of a questionnaire, as well as a website managed by the Chilean Ministry of Health (Minsal). The accuracy of each answer was confirmed by comparison with information retrieved from articles published by indexed journals.

RESULTS

The information provided by the Spanish version of Wikipedia was accurate; nevertheless a few omissions were detected. The quality of the information provided by the Spanish version of Yahoo Answers was inaccurate and confusing. The Minsal website lacked important information on several topics about HPV even though it is managed and endorsed by the government.

CONCLUSIONS

We suggest periodical content reviews to increase the completeness, transparency and correctness of the website.

Six-year multi-centre, observational, post-marketing surveillance of the safety of the HPV-16/18 AS04-adjuvanted vaccine in women aged 10-25 years in Korea

Purpose

To evaluate the safety of HPV‐16/18 AS04‐adjuvanted vaccine when administered as per the PI in Korea.

Methods

A total of 3084 women aged 10–25 years were enrolled in this post‐marketing surveillance from 2008 to 2014. Subjects were invited to receive three doses of the vaccine (0, 1 and 6 months), and participants who received at least one dose were included in the analysis. Adverse events (AEs), adverse drug reactions (ADRs) and serious AEs (SAEs) were recorded after each dose. All AEs, ADRs and SAEs were presented with exact 95% confidence intervals (CI) (NCT01101542).

Results

Injection‐site pain was the most frequent AE and ADR reported by 322 subjects (10.4% [95%CI: 9.4–11.6]); the local pain was transient and lasted 4–7 days in most cases. Dysmenorrhoea and vaginitis were the most common unexpected AEs reported by 30 (1.0% [95%CI: 0.7–1.4]) and 16 subjects (0.7% [95%CI: 0.3–0.8]), respectively. Pain (toe pain, leg pain and body pain [one case each]; foot pain [two cases]) was the most common unexpected ADR reported by five subjects (0.2% [95%CI: 0.1–0.4]). Four subjects reported a single SAE (one case each of exostosis, gastroenteritis, abortion and tonsillitis); none were fatal. All SAEs were assessed as unlikely to be related to vaccination; gastroenteritis, exostosis and tonsillitis resolved during the study period.

Conclusions

This is the first post‐marketing surveillance study in Korea that provides 6‐year safety data for HPV‐16/18 AS04‐adjuvanted vaccine. The vaccine showed an acceptable safety profile and favourable benefit/risk ratio when given to women aged 10–25 years in Korea. © 2017 The Authors. Pharmacoepidemiology & Drug Safety Published by John Wiley & Sons Ltd.

New approaches to VLP-based vaccines

Vaccination is a long and established field of research, and outputs from the research have saved countless millions of lives. The early vaccines were developed with scant regard for the immunological mechanisms at play, largely because they were unknown. We are now in a position to use our knowledge of immunology to rationally design vaccines. This article focusses on the use of virus-like particles (VLPs) as vaccines.

Adverse events following school-based vaccination of girls with quadrivalent human papillomavirus vaccine in Slovenia, 2009 to 2013

Adverse events following immunisation (AEFIs) with qHPV reported to the Slovenian AEFI Registry for the first four school years of the vaccination programme were analysed. We calculated annual reporting rates for 11-14 year-old vaccinees with AEFIs, using the number of qHPV doses distributed within the school-based vaccination programme as the denominator. Between September 2009 and August 2013, 211 AEFIs that occurred in 89 vaccinees were reported, a rate of 149.5 vaccinees with AEFI per 100,000 qHPV doses distributed. For five vaccinees, serious AEFIs (8.4 per 100,000 doses distributed) were reported. The highest reporting rates were for fatigue, headache, and fever (≥ 38.0⁰) (53.8, 40.3, and 35.3 per 100,000 qHPV doses distributed, respectively). As no AEFI resulted in permanent sequelae and they all were categorised as serious only due to the criterion of a minimum of one day of hospitalisation, this provides reassurance for the safety of our school-based HPV vaccination programme. Further AEFI surveillance is warranted to provide data for HPV vaccination programme monitoring and evaluation of its safety.

Safety Profile of the 9-Valent HPV Vaccine: A Combined Analysis of 7 Phase III Clinical Trials

OBJECTIVES

The overall safety profile of the 9-valent human papillomavirus (9vHPV) vaccine was evaluated across 7 Phase III studies, conducted in males and females (nonpregnant at entry), 9 to 26 years of age.

METHODS

Vaccination was administered as a 3-dose regimen at day 1, and months 2 and 6. More than 15 000 subjects received ≥1 dose of 9vHPV vaccine. In 2 of the studies, >7000 control subjects received ≥1 dose of quadrivalent HPV (qHPV) vaccine. Serious and nonserious adverse events (AEs) and new medical conditions were recorded throughout the study. Subjects testing positive for pregnancy at day 1 were not vaccinated; those who became pregnant after day 1 were discontinued from further vaccination until resolution of the pregnancy. Pregnancies detected after study start (n = 2950) were followed to outcome.

RESULTS

The most common AEs (≥5%) experienced by 9vHPV vaccine recipients were injection-site AEs (pain, swelling, erythema) and vaccine-related systemic AEs (headache, pyrexia). Injection-site AEs were more common in 9vHPV vaccine than qHPV vaccine recipients; most were mild-to-moderate in intensity. Discontinuations and vaccine-related serious AEs were rare (0.1% and <0.1%, respectively). Seven deaths were reported; none were considered vaccine related. The proportions of pregnancies with adverse outcome were within ranges reported in the general population.

CONCLUSIONS

The 9vHPV vaccine was generally well tolerated in subjects aged 9 to 26 years with an AE profile similar to that of the qHPV vaccine; injection-site AEs were more common with 9vHPV vaccine. Its additional coverage and safety profile support widespread 9vHPV vaccination.

Impact of 2-, 4- and 9-valent HPV vaccines on morbidity and mortality from cervical cancer

Cervical cancer causes significant morbidity and mortality worldwide. Most cervical cancers are associated with oncogenic human papillomavirus (HPV), and vaccination with any of 3 available HPV vaccines is anticipated to greatly reduce the burden of cervical cancer. This review provides an overview of the burden of HPV, the efficacy and clinical effectiveness of the bivalent (HPV 16, 18), quadrivalent (HPV 6, 11, 16, 18) and 9vHPV (HPV 6, 11, 16, 1831, 33, 45, 52, 58) vaccines in order to assess the anticipated impact on cervical cancer. All three vaccines show high efficacy in prevention of vaccine-specific HPV-type infection and associated high-grade cervical dysplasia in HPV-naïve women. Early clinical effectiveness data for the bivalent and quadrivalent vaccine demonstrate reduced rates of HPV 16 and 18 prevalence in vaccinated cohorts; data evaluating cervical dysplasia and cervical procedures as outcomes will shed further light on the clinical effectiveness of both vaccines. The bivalent vaccine has demonstrated cross-protection to non-vaccine HPV types, including the types in the 9vHPV vaccine. No clinical effectiveness data is yet available for the 9vHPV vaccine.  While HPV vaccination has great promise to reduce cervical cancer morbidity and mortality, estimated benefits are largely theoretical at present. Large population-based clinical effectiveness studies will provide long-term immunogenicity and effectiveness, as well as assessment of cervical cancer as an endpoint, particularly as young vaccinated women enter the appropriate age range to initiate screening for cervical cancer. Strengthening screening and treatment programs will likely have the greatest impact in the short-term on cervical cancer morbidity and mortality.

Current status of human papillomavirus vaccination

PURPOSE OF REVIEW

In this article, we review the impact of the quadrivalent and bivalent prophylactic human papillomavirus (HPV) vaccines on HPV infection and disease, review alternative vaccine dosing schedules, the vaccination of men and the nine-valent HPV vaccine.

RECENT FINDINGS

HPV vaccines have had dramatic impacts on the prevalence of targeted HPV types (6,11,16 and 18), genital warts and precancerous cervical lesions. Population coverage would be facilitated by adopting two-dose schedules, with recent findings that two-dose schedules in young adolescents are as immunogenic as three doses in young adults. Extension of vaccination to men, particularly for men who have sex with men, could further reduce population prevalence of HPV and provide direct protection to men against genital warts and anal, penile and oropharyngeal cancers. The nine-valent HPV vaccine has demonstrated equivalent protection against the four types in the quadrivalent vaccine and high efficacy against the next five commonest causes of cervical cancer (HPV types 31,33,45,52 and 58). If cost-effective, it may extend the spectrum of protection against cervical cancer available through vaccination.

SUMMARY

HPV vaccination is an effective strategy for reducing the burden of HPV-related disease. New schedules, target populations and vaccines promise to expand this potential further.

Adverse events following immunization: real causality and myths

INTRODUCTION

To assure the highest safety of immunization programs, detect adverse events following immunization (AEFIs), eliminate concerns, and reduce the risk of low vaccination coverage, authorities in industrialized countries have collected years of reports of suspected AEFIs and have systematically assessed their clinical importance.

AREAS COVERED

In this paper, the methods used to assess vaccine safety and the results obtained by the analysis of reports, studies, and meta-analyses are discussed.

EXPERT OPINION

Severe AEFIs are rare, and all evaluations of safety of vaccines recommended for both children and adults have demonstrated that the advantages of vaccines are always significantly higher than the problems that they cause, and there is no need to modify recommendations. However, the definition of AEFI is dependent on the vaccines themselves, complicating the definition of an AEFI and explaining why doubts and concerns have been raised. Presently, disease epidemiology data collected in healthy people and in subjects with underlying disease, general vaccine coverage, and the vaccination status of subjects with AEFIs are managed by many independent institutions. Only strict co-operation between these institutions will lead to the successful identification of AEFIs and to a reduction of the weight of anti-vaccine arguments.