Adverse events following Quadrivalent HPV vaccination reported in Sao Paulo State, Brazil, in the first three years after introducing the vaccine for routine immunization (March 2014 to December 2016)

Safety profile assessment of HPV4 and HPV9 vaccines through the passive surveillance system of the Veneto Region (Italy) between 2008 and 2022: A 15-year retrospective observational study

In Veneto Region, HPV vaccine has been actively offered to 12 year-old females since 2008, and to 12 year-old males since 2015. The study aims to analyze the safety profile of HPV4v and HPV9v vaccines and perform a case-by-case review of conditions of interest. Spontaneous reports related to HPV uploaded to the database of the Regional Pharmacovigilance Center between 2008-2022 were included. HPV vaccine doses administered until April 2022 in the Veneto Region were considered to calculate the reporting rate (RR). Potential "safety concerns" examined as conditions of interest were included through Standardized MedDRA or preferred terms searching queries. The level of diagnostic certainty was evaluated as per the Brighton Collaboration case definition criteria. A total of 637 reports and 1316 Adverse Events Following Immunizations (AEFI) were retrieved: 469 for HPV4v (73.6 %) and 168 for HPV9v (26.4 %). Serious reports were 71 (11.1 %): 49 (10.4 %) for HPV4v and 22 (13.1 %) for HPV9v. The RR for serious events between 2008-2022 was 6.9/100,000 administered doses, with no differences by vaccine type. Females and adults showed higher overall RR compared to males and to children and adolescents (p < 0.001), this result was confirmed by stratifying analysis by vaccine type. One case of Guillain Barré syndrome, anaphylactic shock, thrombocytopenia, Henoch Schoenlein purpura and four generalized seizures were reviewed. Vaccinovigilance data from the Veneto Region reaffirm a good safety profile for HPV vaccination and found no vaccine-related unexpected events. Such a detailed analysis may assist healthcare providers to advocate properly for HPV vaccination.

Thrombosis and thromboembolism: Brighton collaboration case definition and guidelines for data collection, analysis, and presentation of immunization safety data

This is a Brighton Collaboration case definition of thrombosis and thromboembolism to be used in the evaluation of adverse events following immunization, and for epidemiologic studies for the assessment of background incidence or hypothesis testing. The case definition was developed by a group of experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of SARS-CoV-2 vaccines. The case definition format of the Brighton Collaboration was followed to develop a consensus definition and defined levels of certainty, after an exhaustive review of the literature and expert consultation. The document underwent peer review by the Brighton Collaboration Network and by selected expert reviewers prior to submission.

Population-Based Incidence of Guillain-Barré Syndrome During Mass Immunization With Viral Vaccines: A Pooled Analysis

Misunderstanding temporal coincidence of adverse events during mass vaccination and invalid assessment of possible safety concerns have negative effects on immunization programs, leading to low immunization coverage. We conducted this systematic review and meta-analysis to identify the incidence rates of GBS that are temporally associated with viral vaccine administration but might not be attributable to the vaccines. By literature search in Embase and PubMed, we included 48 publications and 2,110,441,600 participants. The pooled incidence rate of GBS was 3.09 per million persons (95% confidence interval [CI]: 2.67 to 3.51) within six weeks of vaccination, equally 2.47 per 100,000 person-year (95%CI: 2.14 to 2.81). Subgroup analyses illustrated that the pooled rates were 2.77 per million persons (95%CI: 2.47 to 3.07) for individuals who received the influenza vaccine and 2.44 per million persons (95%CI: 0.97 to 3.91) for human papillomavirus (HPV) vaccines, respectively. Our findings evidence the GBS-associated safety of virus vaccines. We present a reference for the evaluation of post-vaccination GBS rates in mass immunization campaigns, including the SARS-CoV-2 vaccine.

Adolescents' knowledge of HPV and sexually transmitted infections at public high schools in São Paulo: A cross-sectional study

PURPOSE

To assess the knowledge of students from public high schools in poor communities about HPV and Sexually Transmitted Infections and their attitude towards and prevention of such diseases.

PATIENTS AND METHODS

Cross-sectional study with adolescents from public schools of São Paulo - Brazil. Participants were selected for an interview by a randomization program. A questionnaire about knowledge, attitudes, and preventive practices regarding STIs, including HPV, according to sex was administered and answers were analyzed by the Poisson regression model with robust variance.

RESULTS

Median age of the 269 participants was 16 years. The majority was of African descent (68.8%, n = 185), most (74%, n = 199) were religious and the vast majority (90.7%, n = 244) lived with their parents. The Poisson regression revealed statistically significant sex-related differences regarding the following questions: "Do you know how it is prevented?" (PR = 1.12 [1.03‒1.23], p = 0.007); "Have you ever been concerned with HPV?" (PR = 1.10 [1.02‒1.19], p = 0.011); "Have you ever sought health care due to concerns about HPV?" (PR = 1.09 [1.04‒1.14], p < 0.001); "Do you know what a Pap Smear is?" (PR = 1.24 [1.13‒1.36], p < 0.001); "Do you know what the cervix is?" (PR = 1.23 [1.13‒1.34], p < 0.001); "Do you know what cervical cancer is?" (PR = 1.13 [1.04‒1.22], p = 0.004).

CONCLUSIONS

The present results show that adolescents from public schools in poor communities in São Paulo City know little about HPV and cervical cancer. Male adolescents know less than female adolescents and are less concerned with health care.

Update on human papillomavirus - Part II: complementary diagnosis, treatment and prophylaxis

In this nonsystematic review, the complementary diagnosis, treatment, prevention, and control of human papillomavirus are discussed. The histopathology is addressed regarding its indications, main findings and limitations, as a complementary diagnostic method largely used by dermatologists. Electron microscopy is briefly reviewed, along with its contribution to the accumulated knowledge on HPV, as well as the relevance of research in using this technology for future advances in diagnosis and treatment. Molecular information about the virus is continuously increasing, and the practical applications of HPV serology, molecular identification and genotyping are discussed. Vaccines are a valuable tool in primary HPV infection prevention and are now available in many countries; their composition, indications, and adverse effects are revisited. Local and systemic treatment options are reviewed and off-label prescriptions are discussed. Finally, health education focusing on HPV infection as a sexually transmitted infection of worldwide relevance and the many barriers to improve primary and secondary prevention are addressed.

Potential Effects of Human Papillomavirus Type Substitution, Superinfection Exclusion and Latency on the Efficacy of the Current L1 Prophylactic Vaccines

There are >200 different types of human papilloma virus (HPV) of which >51 infect genital epithelium, with ~14 of these classed as high-risk being more commonly associated with cervical cancer. During development of the disease, high-risk types have an increased tendency to develop a truncated non-replicative life cycle, whereas low-risk, non-cancer-associated HPV types are either asymptomatic or cause benign lesions completing their full replicative life cycle. HPVs can also be present as non-replicative so-called “latent” infections and they can also show superinfection exclusion, where cells with pre-existing infections with one type cannot be infected with a different HPV type. Thus, the HPV repertoire and replication status present in an individual can form a complex dynamic meta-community which changes with respect to both time and exposure to different HPV types. In light of these considerations, it is not clear how current prophylactic HPV vaccines will affect this system and the potential for iatrogenic outcomes is discussed in light of recent outcome data.

Trends of Adverse Events Following Immunization (AEFI) Reports of Human Papillomavirus Vaccine in the Valencian Community—Spain (2008–2018)

Vaccine safety surveillance is essential in vaccination programs. We accomplished a descriptive study of surveillance AEFI-reporting rate in human papillomavirus (HPV) vaccine administered in the Valencian Community, Spain. Data were obtained from Spanish Pharmacovigilance Adverse Reactions Data (FEDRA). Reporting rates were calculated using local net doses distributed as the denominator. Trends were assessed using joinpoint regression with annual percent change (APC) reported. The AEFI-reports decreased between 2008 and 2018 in two periods, a fast decreasing rate from 2009 to 2011 (from 192.2 to 24.93 per 100000 doses; APC, −54.9%; 95%CI [−75.2; −17.7]), followed by a stable trend (−13% APC, 95%CI [−26.1; 2.4]). For the age group analysis, only the group aged 14–15 years old followed the same trend with -58.4% (95%CI [−73.9; −33.8]) APC during 2008–2011, and −8.8% (95%CI [−27.7; 15]) APC during 2011-2018. The majority of the reports (73.82%) were nonserious, involving reactions at or near the vaccination site, headache, and dizziness events. No death was reported. AEFI-reporting rates for HPV immunization in the Valencian Community have decreased considerably with two trend periods observed for girls aged 14–15 years old. Currently, the AEFI reporting rate shows a decreasing trend, perhaps following the Weber effect, and it could also be affected by media attention and coverage.