The comparative safety of human papillomavirus vaccines: A Bayesian network meta-analysis

Human papillomavirus infection: Epidemiology, biology, host interactions, cancer development, prevention, and therapeutics

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections worldwide. It is caused by the HPV, a DNA virus that infects epithelial cells in various mucous membranes and skin surfaces. HPV can be categorised into high-risk and low-risk types based on their association with the development of certain cancers. High-risk HPV types, such as HPV-16 and HPV-18, are known to be oncogenic and are strongly associated with the development of cervical, anal, vaginal, vulvar, penile, and oropharyngeal cancers. These types of HPV can persist in the body for an extended period and, in some cases, lead to the formation of precancerous lesions that may progress to cancer if left untreated. Low-risk HPV types, such as HPV-6 and HPV-11, are not typically associated with cancer but can cause benign conditions like genital warts. Genital warts are characterised by the growth of small, cauliflower-like bumps on the genital and anal areas. Although not life-threatening, they can cause discomfort and psychological distress. HPV is primarily transmitted through sexual contact, including vaginal, anal, and oral sex. It can also be transmitted through non-penetrative sexual activities that involve skin-to-skin contact. In addition to sexual transmission, vertical transmission from mother to child during childbirth is possible but relatively rare. Prevention of HPV infection includes vaccination and safe sexual practices. HPV vaccines, such as Gardasil and Cervarix, are highly effective in preventing infection with the most common high-risk HPV types. These vaccines are typically administered to adolescents and young adults before they become sexually active. Safe sexual practices, such as consistent and correct condom use and limiting the number of sexual partners, can also reduce the risk of HPV transmission. Diagnosis of HPV infection can be challenging because the infection is often asymptomatic, especially in men. In women, HPV testing can be done through cervical screening programs, which involve the collection of cervical cells for analysis. Abnormal results may lead to further diagnostic procedures, such as colposcopy or biopsy, to detect precancerous or cancerous changes. Overall, HPV infection is a prevalent sexually transmitted infection with significant implications for public health. Vaccination, regular screening, and early treatment of precancerous lesions are key strategies to reduce the burden of HPV-related diseases and their associated complications. Education and awareness about HPV and its prevention are crucial in promoting optimal sexual health. This study aimed to carry out a literature review considering several aspects involving HPV infection: Global distribution, prevalence, biology, host interactions, cancer development, prevention, therapeutics, coinfection with other viruses, coinfection with bacteria, association with head and neck squamous cell carcinomas, and association with anal cancer.

Comparative Effects of Bivalent, Quadrivalent, and Nonavalent Human Papillomavirus Vaccines in The Prevention of Genotype-Specific Infection: A Systematic Review and Network Meta-Analysis

BACKGROUND

Human papillomavirus (HPV) infection is a major global disease burden and the main cause of cervical cancer. Certain HPV genotypes, with are the most common etiologic pathogens and cause a significant disease burden, are being targeted for vaccine development. However, few studies have focused on the comparative effectiveness of the bivalent HPV (2v-HPV), quadrivalent HPV (4v-HPV), and nonavalent HPV (9v-HPV) vaccines against HPV strain-specific infection. This study investigated the comparative effects of these vaccines against genotype-specific infection.

MATERIALS AND METHODS

We conducted a pairwise and network meta-analysis of published randomized clinical trials of HPV vaccines according to sex and HPV infection status for nine HPV genotypes (HPV 6/11/16/18/31/33/45/52/58).

RESULTS

Overall, 10 randomized controlled trials (12 articles) were included in this study. In the network meta-analysis, no statistically significant differences were observed in the prevention of carcinogenic HPV strains (16/18/31/33/45/52/58) between the 2v-HPV and 4v-HPV vaccines in female HPV infection-naïve populations. However, the 9v-HPV vaccine showed a significantly superior effect compared with 2v-HPV and 4v-HPV vaccines in preventing HPV 31/33/45/52/58 infections. Although 2v-HPV and 4v-HPV vaccines provided some cross-protection against HPV 31/33/45/52/58 infections, the effect was significant only on HPV 31 infection. For HPV 16 and 18, neither statistically significant nor small differences were found in the prevention of HPV infection among the 2v-HPV, 4v-HPV, and 9v-HPV vaccines.

CONCLUSION

Our study complements previous understanding of how the effect of HPV vaccines differs according to the HPV genotype. This is important because HPV genotype prevalence varies among countries. We advocate for continued efforts in vaccinating against HPV, while public health agencies should consider the difference in the vaccine effect and HPV genotype prevalence when implementing HPV vaccination in public vaccination programs.

COVID-19 Vaccine: Predicting Vaccine Types and Assessing Mortality Risk Through Ensemble Learning Agorithms

Background: There is no doubt that vaccination is crucial for preventing the spread of diseases; however, not every vaccine is perfect or will work for everyone. The main objective of this work is to predict which vaccine will be most effective for a candidate without causing severe adverse reactions and to categorize a patient as potentially at high risk of death from the COVID-19 vaccine. Methods: A comprehensive analysis was conducted using a dataset on COVID-19 vaccine adverse reactions, exploring binary and multiclass classification scenarios. Ensemble models, including Random Forest, Decision Tree, Light Gradient Boosting, and extreme gradient boosting algorithm, were utilized to achieve accurate predictions. Class balancing techniques like SMOTE, TOMEK_LINK, and SMOTETOMEK were incorporated to enhance model performance. Results: The study revealed that pre-existing conditions such as diabetes, hypertension, heart disease, history of allergies, prior vaccinations, other medications, age, and gender were crucial factors associated with poor outcomes. Moreover, using medical history, the ensemble learning classifiers achieved accuracy scores ranging from 75% to 87% in predicting the vaccine type and mortality possibility. The Random Forest model emerged as the best prediction model, while the implementation of the SMOTE and SMOTETOMEK methods generally improved model performance. Conclusion: The random forest model emerges as the top recommendation for machine learning tasks that require high accuracy and resilience. Moreover, the findings highlight the critical role of medical history in optimizing vaccine outcomes and minimizing adverse reactions.

Effect of heat-clearing and dampness-eliminating Chinese medicine for high-risk cervical cancer papillomavirus infection: a systematic review and meta-analysis of randomized controlled trials

Background

Heat-clearing and dampness-eliminating Chinese medicine (HDCM) has been studied in clinical trials for cervical HPV infection for decades. However, there has been little comprehensive assessment of the strength and quality of the evidence. Therefore, this study conducted a systematic review and meta-analysis to assess the effectiveness and safety of HDCM in high-risk cervical HPV-infected patients.

Methods

The research focus questions were constructed in accordance with the criteria of participants, intervention, comparison, and outcomes (PICO), and a protocol was registered in PROSPERO. Comprehensive and systematic searches and inquiries in eight electronic databases were conducted from their inception to 30th June 2022. Further, a systematic review and meta-analysis of all randomized controlled trials (RCTs) were conducted to evaluate the HDCM therapy methods.

Results

A total of 12 studies were eligible for inclusion, including 1,574 patients. Data synthesis showed that the HPV clearance rate of HDCM groups was superior to both interferon and follow-up groups (RR = 1.40,95% CI:1.15, 1.71, P < 0.01) and (RR = 3.15, 95% CI:2.43,4.08, P < 0.01), respectively. HDCM was proven to exhibit greater potential in reducing HPV-DNA virus load (MD = -5.16, 95% CI: -5.91, -4.41, P < 0.01). The reversal rate of cervical intraepithelial neoplasia (CIN) for HDCM groups was approximately 2.8 times (RR = 2.80, 95% CI: 2.19, 3.57, P < 0.01), as high as the follow-up groups. Additionally, the recurrence rate of HR-HPV at the end of follow-up in this meta-analysis was reported to be lower in HDCM groups compared to follow-up groups [6.81% (16/235) and 14.65% (29/198), respectively]. The most commonly used Chinese herbal remedies were as follows: Huangbai (Phellodendron chinense var.Glabriusculum C.K. Schneid.), Kushen (Sophora flavescens Aiton), Daqingye (Isatis indigotica Fortune), Zicao (Arnebia hi-spidissima DC.), Baihuasheshecao (Hedyotis diffusa Spreng.), Banlangen (Isatis tinctoria subsp.tinctoria L.), Huzhang (Reynoutria japonica Houtt.), and Huangqi (Orobanche astragali Mouterde).

Conclusion

HDCM interventions appeared to generate significant effects on enhancing the rate of HR-HPV clearance, reducing the HPV-DNA virus load, and increasing the CIN regression rate. Some active components were confirmed to be responsible for this efficacy, which deserves further exploration.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022333226.

Reasons for refusal of the human papillomavirus vaccine among young cancer survivors

BACKGROUND

Cancer survivors are at risk for developing subsequent human papillomavirus (HPV)-related malignancies. HPV vaccination rates among survivors remain low, and the reasons for refusal of the vaccine are unclear in this population.

METHODS

The authors conducted a secondary analysis of data from an open-label clinical trial evaluating the immunogenicity and safety of the HPV vaccine among vaccine-naive cancer survivors who were 9-26 years old and 1-5 years from the completion of their cancer treatment. Survivors/parents who declined trial participation were asked their reasons for declining. Refusal reasons were categorized, and multivariable logistic regression models were developed to identify associations between survivor characteristics and primary refusal reasons.

RESULTS

Among the 301 survivors who refused participation in the clinical trial, 215 (71.4%) refused for reasons related to the HPV vaccine. Reasons for vaccine-related refusal included safety concerns, vaccine hesitancy/disinterest, external influences, vaccine-related information deficits, and health beliefs/family decisional processes. Compared with males, females were more likely to refuse for reasons related to health beliefs/family decisional processes (odds ratio [OR], 2.08; 95% confidence interval [CI], 1.12-3.93; p = .022) and were less likely to do so because of external influences (OR, 0.43; 95% CI, 0.19-0.92; p = .035). Survivors approached about participation during the latter years of the trial were more likely to refuse because of safety concerns (OR, 3.33; 95% CI, 1.55-7.69; p = .003).

CONCLUSIONS

Cancer survivors refused participation in an open-label trial evaluating the immunogenicity and safety of the HPV vaccine primarily because of vaccine-related concerns that were unrelated to the research study. Many of these concerns are potentially addressable by health care providers using evidence-based messages tailored to the cancer survivor population.

Comparative efficacy of human papillomavirus vaccines: systematic review and network meta-analysis

OBJECTIVES

Despite their use, differences in human papillomavirus (HPV) vaccine efficacies remain uncertain. This study assesses efficacy differences among bivalent, quadrivalent, and nine-valent HPV (2vHPV, 4vHPV, and 9vHPV) vaccines.

METHODS

PubMed, Web of Science, Embase, and the Cochrane Library were searched for randomized controlled trials comparing HPV vaccine efficacy against persistent infection (≥6 months) and cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Network meta-analysis yielded direct and indirect comparisons. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were reported, and robustness was evaluated via sensitivity analysis.

RESULTS

In 11 randomized controlled trials with 58,881 healthy women, for persistent infection with HPV 16, 9vHPV was most effective at 97% (RR = 0.03, 95% CI: 0.01-0.08); for HPV 18, 2vHPV (Cecolin) was most effective at 98% (RR = 0.02, 95% CI: 0.00-0.29); for CIN2+ associated with HPV 16 and 18, 4vHPV was most effective at 99% (RR = 0.01, 95% CI: 0.00-0.10) and 97% (RR = 0.03, 95% CI: 0.00-0.45), respectively; for persistent infection with HPV 31, 33, 45, 52, and 58, 9vHPV was ≥ 95% effective; both 2vHPV vaccines were cross-effective against HPV 31, 33, and 45; and 4vHPV was cross-effective against HPV 31.

CONCLUSIONS

HPV vaccine efficacies differ for different HPV types. Additional data are needed to determine the cross-efficacy of 2vHPV (Cecolin).

Neuralgic Amyotrophy with Concomitant Hereditary Neuropathy with Liability to Pressure Palsy as a Cause of Dropped Shoulder in a Child after Human Papillomavirus Vaccination: A Case Report

Hereditary neuropathy with liability to pressure palsy (HNPP) makes nerves increasingly susceptible to mechanical pressure at entrapment sites. Neuralgic amyotrophy (NA) can cause sudden regional weakness following events to which the patient is immunologically predisposed, such as vaccination. However, NA related to human papilloma virus (HPV) vaccination is seldom reported. We describe the case of a child with NA as the cause of a dropped shoulder following the administration of the HPV vaccine. Underlying asymptomatic HNPP was confirmed in this patient based on the electrodiagnostic findings and genetic analysis. We speculate that HPV vaccination elicited an immune-mediated inflammatory response, resulting in NA. Our patient with pre-existing HNPP might be vulnerable to the occurrence of an immune-mediated NA, which caused the dropped shoulder.