Prevalence of high-risk HPV genotypes in sub-Saharan Africa according to HIV status: a 20-year systematic review

OBJECTIVES

This review assessed the rate of high-risk human papillomavirus (HPV) infection among women living in sub-Saharan Africa. It also determined the prevalence of high-risk HPV (hrHPV) among human immunodeficiency virus (HIV) seropositive (HIV+) and seronegative (HIV-) women in sub-Saharan Africa, pre-2010 and post-2010.

METHODS

In this systematic review, Google Scholar, PubMed Central, and Embase were searched to identify cohort and case-control studies that investigated the relationship between HIV and HPV infection. The database searches yielded 17 studies published between 1999 and 2018.

RESULTS

In the general population, the prevalence of any HPV/multiple HPV infections was higher among HIV+ (53.6/22.6%) than among HIV- women (26.5/7.3%) with odds ratios of 3.22 and 3.71, respectively (95% confidence interval, 3.00 to 3.42 and 2.39 to 5.75, p<0.001). The prevalent HPV genotypes among HIV+ and HIV- women diagnosed with invasive cervical cancer (ICC) were HPV-16/18 and HPV-45. The prevalence of HPV-16, HPV-18, and HPV-45 was lower in 1999-2010 (3.8, 1.7, and 0.8%, respectively) than in 2011-2018 (19.1, 6.0, and 3.6%, respectively). Among women diagnosed with ICC, HIV+ women had a higher prevalence of HPV-56, HPV-31, and HPV-51 (7.3, 5.3, and 3.3%, respectively) than HIV- women (1.3, 2.2, and 0.4%, p<0.001, p=0.050, and p=0.013, respectively).

CONCLUSIONS

The prevalence of HPV infection, multiple HPV infections, and non-vaccine HPV types were higher among HIV+ women than among HIV- women in sub-Saharan Africa. Although HIV infection influences the distribution of HPV types, this study suggests that cervical cancer incidence in sub-Saharan Africa is primarily driven by the prevalence of vaccine hrHPVs, especially HPV-16 and HPV-18.

Natural and vaccine-induced B cell-derived systemic and mucosal humoral immunity to human papillomavirus

Introduction: Human papillomavirus (HPV) are the causative agent of mucosal neoplasia. Both cervical, anal and oropharyngeal cancers incidence is constantly increasing, making the HPV infection, a significant worldwide concern. Together, the CD8+ T cytotoxic cell-mediated response and the HPV-specific antibody response control most of the HPV infections before the development of cancers.Areas covered: We searched the MEDLINE and EMBASE databases and identified 228 eligible studies from 1987 to 2019 which examines both naturally acquired and vaccine induced humoral immunity against HPV infection in female and male subjects from worldwide origin. Herein, we synthesize current knowledge on the features of systemic and mucosal humoral immunity against HPV. We discuss the issues of the balance between the viral clearance or the escape to the host immune response, the differences between natural and vaccine-induced HPV-specific antibodies and their neutralizing capability. We also discuss the protection afforded after natural infection or following prophylactic vaccination.Expert opinion: Understanding the antibody response induced by HPV infection has led to the design of first-generation prophylactic vaccines. Now, prophylactic vaccination induces protective and long-lasting antibody response which would also strengthened the natural moderate humoral response in people previously exposed to the virus.

Self-collection based HPV testing for cervical cancer screening among women living with HIV in Uganda: a descriptive analysis of knowledge, intentions to screen and factors associated with HPV positivity

Background

Women living with HIV (WHIV) are disproportionately impacted by cervical dysplasia and cancer. The burden is greatest in low-income countries where limited or no access to screening exists. The goal of this study was to describe knowledge and intentions of WHIV towards HPV self-collection for cervical cancer screening, and to report on factors related to HPV positivity among women who participated in testing.

Methods

A validated survey was administered to 87 HIV positive women attending the Kisenyi Health Unit aged 30–69 years old, and data was abstracted from chart review. At a later date, self-collection based HPV testing was offered to all women. Specimens were tested for high risk HPV genotypes, and women were contacted with results and referred for care. Descriptive statistics, Chi Square and Fischer-exact statistical tests were performed.

Results

The vast majority of WHIV (98.9%) women did not think it necessary to be screened for cervical cancer and the majority of women had never heard of HPV (96.4%). However, almost all WHIV found self-collection for cervical cancer screening to be acceptable. Of the 87 WHIV offered self-collection, 40 women agreed to provide a sample at the HIV clinic. Among women tested, 45% were oncogenic HPV positive, where HPV 16 or 18 positivity was 15% overall.

Conclusions

In this group of WHIV engaged in HIV care, there was a high prevalence of oncogenic HPV, a large proportion of which were HPV genotypes 16 or 18, in addition to low knowledge of HPV and cervical cancer screening. Improved education and cervical cancer screening for WHIV are sorely needed; self-collection based screening has the potential to be integrated with routine HIV care in this setting.

The levels of anti-HPV16/18 and anti-HPV31/33/35/45/52/58 antibodies among AS04-adjuvanted HPV16/18 vaccinated and non-vaccinated Ugandan girls aged 10-16 years

BACKGROUND

Data on Human Papilloma virus (HPV) vaccine immune response in sub-Saharan Africa is still sparse yet such knowledge is critical for optimal implementation and monitoring of HPV vaccines. Our primary objective was to evaluate levels of anti-HPV-16/18 antibodies and six other 'high risk' HPV (hrHPV) types among the vaccinated and unvaccinated Ugandan girls.

METHODS

We conducted a cross sectional study among AS04-adjuvanted HPV-16/18 vaccinated and unvaccinated school girls aged 10-16 years in Western Uganda using purposive sampling. The vaccinated girls were at 18 months post vaccination. After consenting and assenting, data was collected using interviewer administered questionnaires for demographics and sexual history. Blood was drawn from which serum samples were analysed by the multiplex HPV serology technology to determine anti-HPV antibody levels to HPV-16/18 and six other hrHPV types (31, 33, 35, 45, 52 and 58). The antibody levels were expressed as Median Fluorescent Intensity (MFI). A total of 207 vaccinated [mean age 13.1 years (SD 1.5); range 10-16 years] and 197 unvaccinated girls [mean age 13.6 years (SD 1.3); range 10-16 years] participated in the study. Sexual activity was self reported among 14/207 (6.8%) vaccinated and 5/197 (2.5%) unvaccinated girls. The MFI levels for HPV-16 and HPV-18 were 15 and 20 times higher respectively in the vaccinated girls than in the unvaccinated girls. HPV-16 mean MFI level was 4691(SD 1812; 95% CI: 4438-4958) among the vaccinated compared to 218 (SD 685; 95% CI: 190-252) among the unvaccinated girls. For HPV-18 the mean MFI level was 1615 (SD 1326; 95% CI: 1470-1776) among the vaccinated compared to MFI 103 (SD 506; 95% CI: 88 -121) among unvaccinated girls. In addition antibody levels to non vaccine hrHPV types (31, 33, 35, 45, 52 and 58) were all significantly higher in the vaccinated group than in the unvaccinated group (p<0.01).

CONCLUSION

The AS04-Adjuvanted HPV-16/18 vaccinated girls showed a higher level of antibodies to HPV-16/18 and other non-vaccine hrHPV types compared to the unvaccinated girls. This may translate into protection against HPV-16/18 and other hrHPV types.

Is there an association between HIV-1 genital shedding and cervical intraepithelial neoplasia 2/3 among women on antiretroviral therapy?

OBJECTIVE

Given the high prevalence of cervical intraepithelial neoplasia (CIN) grade 2/3 among HIV-infected women, we sought to examine the relationship between CIN 2/3 and HIV-1 genital shedding among women on highly active antiretroviral therapy (HAART).

MATERIALS AND METHODS

Paired plasma and cervical wick specimens for HIV-1 RNA measurements were obtained from 44 HIV-infected women with biopsy-confirmed CIN 2/3 (cases) and 44 age-matched HIV-infected women with normal cervical findings on colposcopy (controls). All subjects tested negative for sexually transmitted infections and had been stable on HAART for at least 3 months. HIV-1 viral load was measured in both blood and cervical specimens using commercial real-time polymerase chain reaction assays.

RESULTS

Cervical intraepithelial neoplasia 2/3 was not significantly associated with the detection or magnitude of plasma or cervical HIV-1 RNA shedding. HIV was detected in the plasma in 10 cases (23%) and 10 controls (25%) (odds ratio = 1.0; 95% confidence interval = 0.33-3.1). Cervical HIV-1 was detected in 6 cases (13.6%) and 9 controls (20.4%) (odds ratio = 0.61; 95% confidence interval = 0.20-1.90). Mean HIV-1 concentration in cervical secretions among women with CIN 2/3 who shed was 2.93 log10 copies versus 2.72 among controls (p = .65).

CONCLUSIONS

Among women on HAART, we found no relationship between CIN 2/3 and HIV-1 genital shedding.

Anal intraepithelial neoplasia and squamous cell carcinoma in HIV-infected adults

Anal cancer is one of the most common non-AIDS-defining malignancies in the era of combination antiretroviral therapy. Its precursor lesion, anal intraepithelial neoplasia (AIN), is highly prevalent in HIV-infected populations. More than 90% of anal squamous cell cancers are attributable to human papillomavirus (HPV). While the biology of HPV-related intraepithelial neoplasia is consistent across lower anogenital sites, the natural history of AIN is not well established and cannot be assumed to be identical to that of cervical intraepithelial neoplasia. Screening strategies to prevent anal cancer should be developed based on robust natural history data in HIV-infected and uninfected populations. Likewise, treatments need to be tested in randomized clinical trials, and reserved for those at significant risk of progression to cancer. This review covers the epidemiology, pathogenesis and immunology of HPV infection, AIN and anal cancer, and summarizes the current diagnosis, screening and treatment strategies in HIV-infected adults.

Sexual and reproductive health and HIV services: integrating HIV/AIDS and cervical cancer prevention and control

People living with HIV are at an increased risk of acquiring HPV and of developing evolutive cervical cancers (women) and penile and anal cancers (men). Low-cost screening-visual inspection with acetic acid, HPV DNA diagnostics and primary care level treatment, cryotherapy for cervical intraepithelial neoplasia (CIN 2), and primary prevention through HPV vaccination of girls aged 9-13 years-makes the goal of eliminating cervical cancer possible in the long term. Integration of cervical cancer screening and treatment into a sexual and reproductive health service package raises programmatic questions and calls for a continuum of care. The latter is only possible when adequate cytopathology skills and treatment for advanced cancer conditions are available. The present paper highlights the role of member societies of the International Federation of Gynecology and Obstetrics (FIGO) in developing the base for an integrated package that responds to women's sexual and reproductive health needs.

Aspects of prophylactic vaccination against cervical cancer and other human papillomavirus-related cancers in developing countries

Cervical cancer and other human papillomavirus- (HPV-) related cancers are preventable, but preventive measures implemented in developing countries and especially in low-income rural regions have not been effective. Cervical cancer burden derived from sexually transmitted HPV infections is the heaviest in developing countries, and a dramatic increase in the number of cervical cancer cases is predicted, if no intervention is implemented in the near future. HPV vaccines offer an efficient way to prevent related cancers. Recently implemented school-based HPV vaccination demonstration programmes can help tackle the challenges linked with vaccine coverage, and access to vaccination and health services, but prevention strategies need to be modified according to regional characteristics. In urban regions WHO-recommended vaccination strategies might be enough to significantly reduce HPV-related disease burden, but in the rural regions additional vaccination strategies, vaccinating both sexes rather than only females when school attendance is the highest and applying a two-dose regime, need to be considered. From the point of view of both public health and ethics identification of the most effective prevention strategies is pivotal, especially when access to health services is limited. Considering cost-effectiveness versus justice further research on optional vaccination strategies is warranted.