Human Papillomavirus Antibody Levels and Quadrivalent Vaccine Clinical Effectiveness in Perinatally Human Immunodeficiency Virus-infected and Exposed, Uninfected Youth

Efficacy, effectiveness and immunogenicity of reduced HPV vaccination schedules: A review of available evidence

Background

Current National Advisory Committee on Immunization (NACI) guidance recommends human papillomavirus (HPV) vaccines be administered as a two or three-dose schedule. Recently, several large clinical trials have reported the clinical benefit of a single HPV vaccine dose. As a result, the World Health Organization released updated guidance on HPV vaccines in 2022, recommending a two-dose schedule for individuals aged 9-20 years, and acknowledging the use of an alternative off-label single dose schedule.

Objective

The objective of this overview is to provide a detailed account of the available evidence comparing HPV vaccination schedules, which was considered by NACI when updating recommendations on HPV vaccines.

Methods

To identify relevant evidence, existing systematic reviews were leveraged where possible. Individual studies were critically appraised, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess the certainty of evidence.

Results

Available evidence suggests that a one, two, or three-dose HPV vaccine schedule may provide similar protection from HPV infection. While antibody levels against HPV vaccine types were statistically significantly lower with a single dose schedule compared to two or three doses, titres were sustained for up to 16 years. The clinical significance of lower antibody titres is unknown, as there is no established immunologic correlate of protection.

Conclusion

While the available evidence on single-dose HPV vaccination schedules shows a one-dose schedule is highly effective, continued follow-up of single-dose cohorts will be critical to understanding the relative duration of protection for reduced dose schedules and informing future NACI guidance on HPV vaccines.

Human papillomavirus infection among adolescents living with HIV: a focus on prevention

PURPOSE OF REVIEW

To highlight recent data on HPV infection and cervical precancerous lesions in adolescents with HIV, and priorities for primary and secondary HPV prevention.

RECENT FINDINGS

Incident and persistent high-risk HPV infections and cervical abnormalities are higher among young women with perinatally acquired HIV compared to their HIV-negative peers; data on HPV among males with perinatally acquired HIV are scarce. HPV vaccination is highly effective in preventing HPV-related disease, but antibody titers may decline in people with HIV. It remains unclear if emerging recommendations to reduce vaccine schedules from three doses to two or one dose are appropriate for children and adolescents with perinatally acquired HIV. Due to higher risks of HPV-related cancers, screening guidelines for cervical cancer differ in their frequency and age at initiation for women with HIV, but there are no recommendations for women with perinatally acquired HIV; nor for anal cancer screening for men with perinatally acquired HIV.

SUMMARY

Data on the effectiveness of reduced HPV vaccine schedules in children and adolescents with HIV are needed. Implementation research to guide strategies for vaccination, screening, and treatment should include children, adolescents, and young adults with perinatally acquired HIV to ensure they are not left behind.

HIV and skin infections

HIV infection alters the skin microbiome and predisposes to a wide range of cutaneous infections, from atypical presentations of common skin infections to severe disseminated infections involving the skin that are AIDS-defining illnesses. Bacterial infection of the skin, most commonly caused by Staphylococcus aureus, occurs frequently and can result in bacteremia. Nontuberculous mycobacterial infections that are usually localized to the skin may disseminate, and guidance on the treatment of these infections is limited. Herpes simplex can be severe, and less common presentations such as herpetic sycosis and herpes vegetans have been reported. Severe herpes zoster, including disseminated infection, requires intravenous antiviral treatment. Viral warts can be particularly difficult to treat, and in atypical or treatment-resistant cases a biopsy should be considered. Superficial candidosis occurs very commonly in people living with HIV, and antifungal resistance is an increasing problem in non-albicans Candida species. Systemic infections carry a poor prognosis. In tropical settings the endemic mycoses including histoplasmosis are a problem for people living with HIV, and opportunistic infections can affect those with advanced HIV in all parts of the world. Most cutaneous infections can develop or worsen as a result of immune reconstitution in the weeks to months after starting antiretroviral therapy. Direct microscopic examination of clinical material can facilitate rapid diagnosis and treatment initiation, although culture is important to provide microbiological confirmation and guide treatment.

State-of-the-Science of human papillomavirus vaccination in women with human immunodeficiency Virus: Summary of a scientific workshop

The burden of cervical cancer is disproportionately distributed globally, with the vast majority of cases occurring in low- and middle-income countries. Women with human immunodeficiency virus (HIV) (WWH) are at increased risk of human papillomavirus (HPV) infection and cervical cancer as compared to HIV-negative individuals. HPV vaccination remains a priority in regions with a high burden of cervical cancer and high HIV prevalence. With HPV vaccines becoming more accessible, optimal use beyond the initial World Health Organization-recommended target population of 9 to 14-year-old girls is an important question. In March 2022, a group of experts in epidemiology, immunology, and vaccinology convened to discuss the state-of-the-science of HPV vaccination in WWH. This report summarizes the proceedings: review of HIV epidemiology and its intersection with cervical cancer burden, immunology, HPV vaccination including reduced-dose schedules and experience with other vaccines in people with HIV (PWH), HPV vaccination strategies and knowledge gaps, and outstanding research questions. Studies of HPV vaccine effectiveness among WWH, including duration of protection, are limited. Until data from ongoing research is available, the current recommendation for WWH remains for a multi-dose HPV vaccination regimen. A focus of the discussion included the potential impact of HIV acquisition following HPV vaccination. With no data currently existing for HPV vaccines and limited information from non-HPV vaccines, this question requires further research. Implementation research on optimal HPV vaccine delivery approaches for WWH and other priority populations is also urgently needed.

Efficacy and Durability of Immune Response after Receipt of HPV Vaccines in People Living with HIV

People living with HIV (PLH) experience higher rates of HPV infection as well as an increased risk of HPV-related disease, including malignancies. Although they are considered a high-priority group for HPV vaccination, there are limited data regarding the long-term immunogenicity and efficacy of HPV vaccines in this population. Seroconversion rates and geometric mean titers elicited by vaccination are lower in PLH compared to immunocompetent participants, especially in individuals with CD4 counts below 200 cells/mm³ and a detectable viral load. The significance of these differences is still unclear, as a correlate of protection has not been identified. Few studies have focused on demonstrating vaccine efficacy in PLH, with variable results depending on the age at vaccination and baseline seropositivity. Although waning humoral immunity for HPV seems to be more rapid in this population, there is evidence that suggests that seropositivity lasts at least 2-4 years following vaccination. Further research is needed to determine the differences between vaccine formulations and the impact of administrating additional doses on durability of immune protection.

Lifetime prevalence and adherence rate of cervical cancer screening among women living with HIV: a systematic review and meta-analysis

INTRODUCTION

Women living with HIV (WLWH) are more likely to develop cervical cancer. Screening and available healthcare can effectively reduce its incidence and mortality rates. We aimed to summarize the lifetime prevalence and adherence rate of cervical cancer screening among WLWH across low- and middle-income countries (LMICs), and high-income countries (HICs).

METHODS

We systematically searched PubMed, Web of Science and Embase for studies published between database inception and 2 September 2022, without language or geographical restrictions. Those reporting the lifetime prevalence and/or adherence rate of cervical cancer screening among WLWH were included. Pooled estimates across LMICs and HICs were obtained using DerSimonian-Laird random-effects models. When the number of eligible studies was greater than 10, we further conducted stratified analyses by the World Health Organization (WHO) region, setting (rural vs. urban), investigation year, screening method, type of cervical cancer screening programme, age and education level.

RESULTS

Among the 63 included articles, 26 provided data on lifetime prevalence, 24 on adherence rate and 13 on both. The pooled lifetime prevalence in LMICs was 30.2% (95% confidence interval [CI]: 21.0-41.3), compared to 92.4% in HICs (95% CI: 89.6-94.6). The pooled adherence rate was 20.1% in LMICs (95% CI: 16.4-24.3) and 59.5% in HICs (95% CI: 51.2-67.2).

DISCUSSION

There was a large gap in cervical cancer screening among WLWH between LMICs and HICs. Further analysis found that those in LMICs had higher lifetime prevalence in subgroups with urban settings, with older age and with higher education levels; and those in HICs had higher adherence in subgroups with younger age and with higher education levels.

CONCLUSIONS

Cervical cancer screening among WLWH falls considerably short of the WHO's goal. There should be continuous efforts to further increase screening among these women, especially those residing in the rural areas of LMICs and with lower education levels.

Living with HIV and Getting Vaccinated: A Narrative Review

After 40 years of its appearance, human immunodeficiency virus (HIV) infection remains a leading public health challenge worldwide. Since the introduction of antiretroviral treatment (ART), HIV infection has become a chronic condition, and people living with HIV could have life expectancies close to those of the general population. People with HIV often have an increased risk of infection or experience more severe morbidity following exposure to vaccine-preventable diseases. Nowadays, several vaccines are available against bacteria and viruses. However, national and international vaccination guidelines for people with HIV are heterogeneous, and not every vaccine is included. For these reasons, we aimed to perform a narrative review about the vaccinations available for adults living with HIV, reporting the most updated studies performed for each vaccine among this population. We performed a comprehensive literature search through electronic databases (Pubmed-MEDLINE and Embase) and search engines (Google Scholar). We included English peer-reviewed publications (articles and reviews) on HIV and vaccination. Despite widespread use and guideline recommendations, few vaccine trials have been conducted in people with HIV. In addition, not all vaccines are recommended for people with HIV, especially for those with low CD4 cells count. Clinicians should carefully collect the history of vaccinations and patients' acceptance and preferences and regularly check the presence of antibodies for vaccine-preventable pathogens.

Prevention Strategies and Early Diagnosis of Cervical Cancer: Current State and Prospects

Cervical cancer ranks third among all new cancer cases and causes of cancer deaths in females. The paper provides an overview of cervical cancer prevention strategies employed in different regions, with incidence and mortality rates ranging from high to low. It assesses the effectiveness of approaches proposed by national healthcare systems by analysing data published in the National Library of Medicine (Pubmed) since 2018 featuring the following keywords: "cervical cancer prevention", "cervical cancer screening", "barriers to cervical cancer prevention", "premalignant cervical lesions" and "current strategies". WHO's 90-70-90 global strategy for cervical cancer prevention and early screening has proven effective in different countries in both mathematical models and clinical practice. The data analysis carried out within this study identified promising approaches to cervical cancer screening and prevention, which can further enhance the effectiveness of the existing WHO strategy and national healthcare systems. One such approach is the application of AI technologies for detecting precancerous cervical lesions and choosing treatment strategies. As such studies show, the use of AI can not only increase detection accuracy but also ease the burden on primary care.

Human Papillomavirus Vaccine Impact and Effectiveness in Six High-Risk Populations: A Systematic Literature Review

Specific adult populations known to be at high risk for human papillomavirus (HPV)-related disease, such as men who have sex with men, are inconsistently included in national immunization programs. No compilation of the evidence on the real-world impact and effectiveness of HPV vaccines across these populations exists. This systematic literature review identifies and synthesizes the evidence of the real-world impact and effectiveness of the quadrivalent and nonavalent HPV vaccines in high-risk populations: women with prior/current HPV-related anogenital disease, men who have sex with men, immunocompromised/immunosuppressed individuals, female sex workers, transgender and non-binary individuals, and patients with recurrent respiratory papillomatosis (RRP). The outcomes included anogenital precancers/cancers, head and neck cancers, genital warts, and RRP recurrence. From the 2216 records identified, 30 studies (25 effectiveness and 5 impact studies) were included in this systematic literature review. The results, quantity, and quality of these studies were highly variable. The evidence for effectiveness was of high quality only in women with prior/current cervical disease and in individuals with RRP, the most frequently studied populations. No studies of transgender/non-binary individuals or female sex workers were identified. The real-world evidence supports HPV vaccination among women with prior cervical disease and individuals with RRP. Significant real-world data gaps remain in these high-risk populations.

Long-term human papillomavirus vaccination effectiveness and immunity in Rwandan women living with and without HIV: a study protocol

INTRODUCTION

Prophylactic human papillomavirus (HPV) vaccines have been shown to be highly effective in protecting women against cervical infections, high-grade abnormalities and cancer caused by the targeted HPV types. However, the evidence for their effectiveness in women living with HIV (WLWH) is less clear.

METHODS

WLWH and HIV-negative women who likely did (birth cohorts 1996 and later) and WLWH and HIV(-) negative who likely did not (birth cohorts before 1996) receive HPV vaccination (n=3028; 757 participants for each of the four groups). Between groups, we will compare cervicovaginal, anal and oral prevalent and 6-12 month persistent HPV6/11/16/18 infections as measured using a modified AmpFire HPV genotyping assay that tests for 15 high-risk or intermediate-risk HPV genotypes, HPV6 and HPV11. We will also compare the HPV immune response in HPV-vaccinated WLWH to HPV-vaccinated HIV-negative women using an anti-HPV16 and anti-HPV18 ELISA. Vaccination status will be confirmed through national vaccination records.

ANALYSIS

We will calculate point prevalence and prevalence of 6-12 month persisting infections by individual HPV-type specific infections and groups of infections for each anatomic site and for each group of women. Results will be stratified by age at vaccination, age at enrolment and the number of doses (3 vs 2) as well as other factors possibly associated with HPV prevalence. Differences in endpoints between groups, overall and between subgroups, will be tested for statistical significance (p<0.05) using Fisher's exact or Pearson χ² test. Differences in geometric mean titres and seropositivity will be tested for statistical significance using the Mann-Whitney and Fisher's exact tests, respectively.

ETHICS AND DISSEMINATION

The study was approved by the Albert Einstein College of Medicine Institutional Review Board and the Rwanda National Ethics Committee. Results will be disseminated through publication in peer-reviewed journals.

A case study and proposal for publishing directed acyclic graphs: The effectiveness of the quadrivalent human papillomavirus vaccine in perinatally HIV Infected girls

BACKGROUND

Developing a causal graph is an important step in etiologic research planning and can be used to highlight data flaws and irreparable bias and confounding. As a case study, we consider recent findings that suggest human papillomavirus (HPV) vaccine is less effective against HPV-associated disease among girls living with HIV compared to girls without HIV.

OBJECTIVES

To understand the relationship between HIV status and HPV vaccine effectiveness, it is important to outline the key assumptions of the causal mechanisms before designing a study to investigate the effect of the HPV vaccine in girls living with HIV infection.

METHODS

We present a causal graph to describe our assumptions and proposed approach to explore this relationship. We hope to obtain feedback on our assumptions before data analysis and exemplify the process for designing causal graphs to inform an etiologic study.

CONCLUSION

The approach we lay out in this paper may be useful for other researchers who have an interest in using causal graphs to describe and assess assumptions in their own research before undergoing data collection and/or analysis.

Cervical cancer prevention and control in women living with human immunodeficiency virus

Despite being highly preventable, cervical cancer is the fourth most common cancer and cause of cancer death in women globally. In low-income countries, cervical cancer is often the leading cause of cancer-related morbidity and mortality. Women living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome are at a particularly high risk of cervical cancer because of an impaired immune response to human papillomavirus, the obligate cause of virtually all cervical cancers. Globally, approximately 1 in 20 cervical cancers is attributable to HIV; in sub-Saharan Africa, approximately 1 in 5 cervical cancers is due to HIV. Here, the authors provide a critical appraisal of the evidence to date on the impact of HIV disease on cervical cancer risk, describe key methodologic issues, and frame the key outstanding research questions, especially as they apply to ongoing global efforts for prevention and control of cervical cancer. Expanded efforts to integrate HIV care with cervical cancer prevention and control, and vice versa, could assist the global effort to eliminate cervical cancer as a public health problem.

Immunogenicity and Safety of the 9-Valent Human Papillomavirus Vaccine in Solid Organ Transplant Recipients and Adults Infected With Human Immunodeficiency Virus (HIV)

BACKGROUND

The burden of human papillomavirus (HPV) in human immunodeficiency virus (HIV)-infected persons and solid organ transplant (SOT) recipients is high. Clinical trials on HPV vaccines in persons living with HIV and particularly in SOT recipients have been sparse to date, included low numbers of participants, and none of them assessed the 9-valent HPV (9vHPV) vaccine. We investigated the immunogenicity with respect to HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58 and the safety of the 9vHPV vaccine in persons living with HIV and recipients of a kidney, lung, or heart transplant.

METHODS

This is a phase III investigator-initiated study in 100 persons living with HIV (age 18-45 years) and 171 SOT recipients (age 18-55 years). The 9vHPV vaccine was administered at day 1, month 2, and month 6. Primary outcome was seroconversion rates to the 9vHPV types at month 7. Secondary outcomes were geometric mean titers (GMTs) and frequency of adverse events (AEs).

RESULTS

All HIV-infected participants seroconverted for all HPV types, but seroconversion ranged from 46% for HPV45 to 72% for HPV58 in SOT recipients. GMTs ranged from 180 to 2985 mMU/mL in HIV-positive participants and from 17 to 170 mMU/mL in SOT recipients, depending on the HPV type. Injection-site AEs occurred in 62% of participants but were mostly mild or moderate in intensity. None of the reported serious adverse events were deemed vaccine related. No patients died during the study.

CONCLUSIONS

Immunogenicity of the 9vHPV vaccine is high in persons living with HIV but suboptimal in SOT recipients. The vaccine is safe and well tolerated in both groups.

Modelling the impact of prevention strategies on cervical cancer incidence in South Africa

In 2020, the World Health Organisation (WHO) published a strategy to eliminate cervical cancer as a public health concern. In South Africa, despite having a national screening policy in place since 2000, diagnosed cervical cancer incidence has shown no signs of decline. We extend a previously developed individual-based model for human immunodeficiency virus (HIV) and human papillomavirus (HPV) infection to include progression to cervical cancer. The model accounts for future reductions in HIV incidence and prevalence and includes a detailed cervical cancer screening algorithm, based on individual-level data from the public health sector. We estimate the impact of the current prevention programme and alternative screening scenarios on cervical cancer incidence. The South African screening programme prevented 8600 (95%CI 4700-12 300) cervical cancer cases between 2000 and 2019. At current levels of prevention (status quo vaccination, screening, and treatment), age-standardised cervical cancer incidence will reduce from 49.4 per 100 000 women (95%CI 36.6-67.2) in 2020, to 12.0 per 100 000 women (95%CI 8.0-17.2) in 2120. Reaching WHO's prevention targets by 2030 could help South Africa reach elimination (at the 10/100 000 threshold) by 2077 (94% probability of elimination by 2120). Using new screening technologies could reduce incidence to 4.7 per 100 000 women (95%CI 2.8-6.7) in 2120 (44% probability of elimination at the 4/100 000 threshold). HPV vaccination and decreasing HIV prevalence will substantially reduce cervical cancer incidence in the long term, but improvements to South Africa's current screening strategy will be required to prevent cases in the short term. Switching to new screening technologies will have the greatest impact.

A Review of Vaccinations in Adult Patients with Secondary Immunodeficiency

Vaccine-preventable diseases and their related complications are associated with increased morbidity and mortality in patients with altered immunocompetence. Optimised immunisation in this patient population is challenging because of limited data from vaccine trials, suboptimal vaccine efficacy and safety concerns. Reliable efficacy data are lacking among patients with altered immunocompetence, and existing recommendations are mainly based on expert consensus and may vary geographically. Inactivated vaccines can be generally used without risks in this group, but their efficacy may be reduced, and immunisation schedules vary according to local guidelines, age, and type and stage of the underlying disease. Live vaccines, if indicated, should be administered with care because of the risk of vaccine-associated disease. We have reviewed the current evidence on vaccination principles and recommendations in adult patients with secondary immunodeficiencies, including asplenia, HIV infection, stem cell and solid organ transplant, haematological malignancies, inflammatory bowel disease and other chronic disorders.

Considerations for Child Cancer Survivors and Immunocompromised Children to Prevent Secondary HPV-associated Cancers

Survivors of childhood cancer and other immunocompromised children are at high risk for the development of secondary human papillomavirus (HPV)-associated cancers. In this overview, the authors examine the epidemiology of vaccine efficacy, the natural history of HPV infections, and accelerated HPV-associated cancer development in these populations. The authors highlight the opportunities for preventive care and future research directives.

Antibody responses to prophylactic quadrivalent human papillomavirus vaccine at 48 months among HIV-infected girls and boys ages 9-14 in Kenya, Africa

OBJECTIVES

HIV infected children remain at increased risk of HPV associated malignancies as they initiate sexual activity. Though they mount a vigorous immune response to the quadrivalent human papillomavirus (QHPV-6, -11,-16, and -18; Gardasil®) vaccine, durability of the immune response is uncertain. We assessed antibody responses to HPV 6, -11, -16 and -18 for up to 48 months following administration of quadrivalent human papillomavirus vaccine in HIV-infected girls and boys ages 9-14 years in Kenya.

DESIGN

Of 178 girls and boys who had previously received three doses of the quadrivalent HPV vaccine, 176 enrolled into extended follow up for 4 years. HPV antibodies to -6, -11, -16 and -18 were measured at 24, 36 and 48 months after the first vaccine dose using the total immunoglobulin G immunoassay (IgG LIA). We evaluated the magnitude and trend in HPV vaccine response and the effect of plasma HIV-1 RNA on HPV vaccine response from month 24 to month 48 of follow up.

RESULTS

At re-enrollment, 24 months after initial vaccination, median age of participants was 14 years (range 11-17); 167 (95%) were receiving antiretroviral therapy and 110 (66%) had plasma HIV RNA < 40 copies/mL. The rate of HPV seropositivity at 48 months was 83% for HPV-6; 80% for HPV-11; 90% for HPV-16; and 77% for HPV-18. There was a plateau in mean log10 HPV-specific antibody titer between month 24 and 48. The mean log10 HPV-type specific antibody titer for children with undetectable HIV viral load (<40) at the time of vaccination consistently remained higher for the 48 months of follow up compared to children with detectable viral load.

CONCLUSION

Children with HIV infection may retain long term antibody response following HPV immunization. Further work to define whether HIV-infected children are protected from HPV acquisition with low levels of HPV antibodies is needed.

Primary Care Guidance for Persons With Human Immunodeficiency Virus: 2020 Update by the HIV Medicine Association of the Infectious Diseases Society of America

Advances in antiretroviral therapy (ART) have made it possible for persons with human immunodeficiency virus (HIV) to live a near expected life span, without progressing to AIDS or transmitting HIV to sexual partners or infants. There is, therefore, increasing emphasis on maintaining health throughout the life span. To receive optimal medical care and achieve desired outcomes, persons with HIV must be consistently engaged in care and able to access uninterrupted treatment, including ART. Comprehensive evidence-based HIV primary care guidance is, therefore, more important than ever. Creating a patient-centered, stigma-free care environment is essential for care engagement. Barriers to care must be decreased at the societal, health system, clinic, and individual levels. As the population ages and noncommunicable diseases arise, providing comprehensive healthcare for persons with HIV becomes increasingly complex, including management of multiple comorbidities and the associated challenges of polypharmacy, while not neglecting HIV-related health concerns. Clinicians must address issues specific to persons of childbearing potential, including care during preconception and pregnancy, and to children, adolescents, and transgender and gender-diverse individuals. This guidance from an expert panel of the HIV Medicine Association of the Infectious Diseases Society of America updates previous 2013 primary care guidelines.

Effectiveness of 'catch-up' human papillomavirus vaccination to prevent cervical neoplasia in immunosuppressed and non-immunosuppressed women

It is unknown whether the HPV vaccine is effective in immunocompromised women during catch-up ages. We performed a case-control study of 4,357 women with incident CIN2+ (cases) and 5:1 age-matched, incidence-density selected controls (N = 21,773) enrolled in an integrated health care system from 2006 to 2014. Vaccine effectiveness was estimated from multivariable conditional logistic regression models, with results stratified by immunosuppression history, defined as prior HIV infection, solid organ transplant history, or recently prescribed immunosuppressive medications. HPV vaccination resulted in a 19% reduction in CIN2+ rates for women without an immunosuppression history but a nonsignificant 4% reduction for women with an immunosuppression history. Further research is needed to evaluate whether catch-up HPV vaccine effectiveness varies by immunosuppression status, especially given the recent approval of the HPV vaccine for adults up to 45 years of age.

Anal canal cancer in Brazil: why should we pay more attention to the epidemiology of this rare disease?

Anal canal cancer is one of the human papilloma virus (HPV)-associated diseases with increasing incidence. High-risk sexual behaviour and the resurgence of human immunodeficiency virus (HIV) infection, associated with low HPV vaccine coverage, are risk factors for the increased incidence of this cancer. In this paper, the authors point out pertinent questions regarding the greater exposure of the population to some risk factors and discuss the latest epidemiological data of these factors, particularly those of concern to emerging countries like Brazil. The authors also discuss policies adopted that have not been successful to combat the HIV and HPV rise and that have direct consequences on the incidence of anal canal cancer.

HPV vaccination in HIV infection

Persons with HIV are at increased risk of HPV infection, HPV disease, and HPV-related cancers compared to HIV negative persons. In persons with HIV, immune responses to vaccination are often sub-optimal, and while these improve with ART, they often remain lower and decline more rapidly than in HIV-negative individuals. Although the evidence base to support the immunogenicity of HPV vaccines in HIV + ve persons is reasonable, the evidence base to support the efficacy of HPV vaccines in HIV + ve individuals is inconsistent. There is one study in HIV + ve men who have sex with men (MSM) which showed no effect, and two other studies, one in HIV + ve women and one in HIV + ve adolescents that showed reduced effectiveness. All these effectiveness studies used Gardasil 4 (G4). Two studies in HIV + ve persons have shown superior immunogenicity of Cervarix (which uses a TLR4 agonist adjuvant) compared to G4. Studies of Hepatitis B vaccines in HIV + ve persons have shown that either (i) increased number of doses (ii) increased vaccine dose, or (iii) TLR agonist adjuvanted vaccines, all produce increased immunogenicity compared to standard vaccine regimes. Therefore, questions remain as to optimal HPV vaccine regimes in HIV and further clinical trials with different HPV vaccine regimes are needed.