An analysis of HPV infection incidence and clearance by genotype and age in men: The HPV Infection in Men (HIM) Study

High burden of human papillomavirus infection among men in Guangzhou, South China: Implications for HPV vaccination strategies

The epidemiological and clinical aspects of Human Papillomavirus (HPV) infection in women have been extensively studied. However, there is a lack of information regarding HPV characteristics in males. In this study, we conducted a retrospective and observational study of 3737 consecutive male individuals attending outpatient clinics of Guangdong Women and Children Hospital from 2012 to 2023 in Guangzhou, South China, to determine the age- and genotype-specific prevalence of HPV in men. The results showed the overall prevalence of HPV among men was 42.15% (1575/3737), with variations ranging from 29.55% to 81.31% across distinct diagnostic populations. Low-risk HPV6 (15.47%), HPV11 (8.94%), and high-risk HPV52 (5.51%) were the most common types. The annual HPV prevalence decreased significantly (Z = -3.882, p < .001), ranging from 31.44% to 52.90%. 28.77% (1075/3737) of men manifested infection with a singular HPV type, predominantly identified as a low-risk type. The age-specific distribution of HPV infections revealed distinctive peaks in the < 25 y age group (47.60%, 208/437) and the 40-44 y age group (44.51%, 154/346). Notably, the positive rate of Chlamydia trachomatis was significantly higher among HPV-positive individuals in comparison to HPV-negatives (16.14% vs. 11.25%, p < .05). Our findings reveal a substantial prevalence of HPV infection among outpatient men in Guangzhou, South China. It is recommended to consider the inclusion of HPV vaccination for adolescent males in national immunization schedules, once an adequate supply of vaccines is accessible.

Forecasting Disease Burden with a Dynamic Transmission Model of Human Papillomavirus and Recurrent Respiratory Papillomatosis in the United States

Juvenile- and adult-onset recurrent respiratory papillomatosis (JORRP and AORRP) are rare but serious conditions that are caused by oral human papillomavirus (HPV) infections. The proliferation of wart-like growths throughout the respiratory tract can result in medical problems, including death. The current treatment scheme is surgery, though prevention of HPV infection through vaccination is available. A previously developed model for JORRP and AORRP was adapted to the United States using data on disease burden and HPV infection. The model was validated against post-vaccination reductions in disease and used to forecast the future burden of JORRP and AORRP, estimating the impact that HPV vaccination will have on these diseases. Between 2007 (the beginning of HPV vaccination in the US) and 2021, this model estimates that approximately 1393 lives, 22,867 Quality-Adjusted-Life-Years, and over USD 672 million in treatment costs have been saved by HPV vaccination. There is also a substantial reduction in JORRP and AORRP burden, with a 95% reduction in incidence by 2040. Moreover, between 2040 and 2121, the model predicts 3-11 total cases of HPV6/11-related JORRP in the US, and 36-267 total cases of HPV6/11-related AORRP. HPV vaccination in the United States has driven, and will continue to drive, substantial reductions in the public health and economic burden of HPV6/11-related JORRP and AORRP.

Global and regional estimates of genital human papillomavirus prevalence among men: a systematic review and meta-analysis

BACKGROUND

The epidemiology of human papillomavirus (HPV) in women has been well documented. Less is known about the epidemiology of HPV in men. We aim to provide updated global and regional pooled overall, type-specific, and age-specific prevalence estimates of genital HPV infection in men.

METHODS

We conducted a systematic review and meta-analysis to assess the prevalence of genital HPV infection in the general male population. We searched Embase, Ovid MEDLINE, and the Global Index Medicus for studies published between Jan 1, 1995, and June 1, 2022. Inclusion criteria were population-based surveys in men aged 15 years or older or HPV prevalence studies with a sample size of at least 50 men with no HPV-related pathology or known risk factors for HPV infection that collected samples from anogenital sites and used PCR or hybrid capture 2 techniques for HPV DNA detection. Exclusion criteria were studies conducted among populations at increased risk of HPV infection, exclusively conducted among circumcised men, and based on urine or semen samples. We screened identified reports and extracted summary-level data from those that were eligible. Data were extracted by two researchers independently and reviewed by a third, and discrepancies were resolved by consensus. We extracted only data on mucosal α-genus HPVs. Global and regional age-specific prevalences for any HPV, high-risk (HR)-HPV, and individual HPV types were estimated using random-effects models for meta-analysis and grouped by UN Sustainable Development Goals geographical classification.

FINDINGS

We identified 5685 publications from database searches, of which 65 studies (comprising 44 769 men) were included from 35 countries. The global pooled prevalence was 31% (95% CI 27-35) for any HPV and 21% (18-24) for HR-HPV. HPV-16 was the most prevalent HPV genotype (5%, 95% CI 4-7) followed by HPV-6 (4%, 3-5). HPV prevalence was high in young adults, reaching a maximum between the ages of 25 years and 29 years, and stabilised or slightly decreased thereafter. Pooled prevalence estimates were similar for the UN Sustainable Development Goal geographical regions of Europe and Northern America, Sub-Saharan Africa, Latin America and the Caribbean, and Australia and New Zealand (Oceania). The estimates for Eastern and South-Eastern Asia were half that of the other regions.

INTERPRETATION

Almost one in three men worldwide are infected with at least one genital HPV type and around one in five men are infected with one or more HR-HPV types. Our findings show that HPV prevalence is high in men over the age of 15 years and support that sexually active men, regardless of age, are an important reservoir of HPV genital infection. These estimates emphasise the importance of incorporating men in comprehensive HPV prevention strategies to reduce HPV-related morbidity and mortality in men and ultimately achieve elimination of cervical cancer and other HPV-related diseases.

FUNDING

Instituto de Salud Carlos III, European Regional Development Fund, Secretariat for Universities and Research of the Department of Business and Knowledge of the Government of Catalonia, and Horizon 2020.

TRANSLATIONS

For the Spanish and French translations of the abstract see Supplementary Materials section.

Health impact and cost-effectiveness of implementing gender-neutral vaccination with the 9-valent HPV vaccine in Hong Kong

Human papillomavirus (HPV) can cause several diseases, including cancers, in both sexes. In January 2020, the Hong Kong government launched a school-based vaccination program for girls 10-12 years of age with the 9-valent HPV (9vHPV) vaccine for the prevention of HPV-related diseases; however, boys were not included. The current study estimated the potential health and economic impact of a routine gender-neutral vaccination (GNV) approach compared with the current female-only vaccination (FOV) strategy. We used a dynamic transmission model, adapted to Hong Kong. The model estimates changes in HPV-related disease incidence and mortality, treatment costs (in 2019 Hong Kong dollars), quality-adjusted life years (QALY), and incremental cost-effectiveness ratios (ICERs) over a 100-year time horizon. The base case analysis compared FOV with the 9vHPV vaccine with routine GNV (coverage rate 70%) for the prevention of HPV-related diseases. Compared with a FOV approach, routine GNV with the 9vHPV vaccine is predicted to provide greater reductions in cumulative HPV-related disease incidence and mortality, as well as lower HPV-related treatment costs. In the base case analysis, the ICER was $248,354 per QALY for routine GNV. As compared with FOV, routine GNV fell below the cost-effectiveness ceiling of $382,046/year for Hong Kong. These results highlight the potential value of a routine GNV program with the 9vHPV vaccine among 12-year-olds in Hong Kong to reduce the public health and economic burden of HPV-related diseases.

Effectiveness, immunogenicity, and safety of the quadrivalent HPV vaccine in women and men aged 27–45 years

Among women aged 27–45 years, the quadrivalent human papillomavirus (qHPV; HPV6/11/16/18) vaccine was generally well tolerated, efficacious, and immunogenic in the placebo-controlled FUTURE III study (NCT00090220; n = 3253). The qHPV vaccine was also generally well tolerated and highly immunogenic in men aged 27–45 years who participated in the single-cohort mid-adult male (MAM) study (NCT01432574; n = 150). Here, we report results of a long-term follow up (LTFU) extension of FUTURE III with up to 10 years follow-up. To understand the relevance of the mid-adult women LTFU study in the context of mid-adult men vaccination, we report results from post-hoc, cross-study immunogenicity analyses conducted to compare immunogenicity (geometric mean titers; GMTs) at 1-month post-qHPV vaccine dose 3 in women and men aged 27–45 years versus women and men aged 16–26 years from prior efficacy studies. The qHPV vaccine demonstrated durable protection against the combined endpoint of HPV6/11/16/18-related high-grade cervical dysplasia and genital warts up to 10 years (median 8.9) post-dose 3 and sustained HPV6/11/16/18 antibody responses through approximately 10 years in women aged 27–45 years. Efficacy of qHPV vaccine in men aged 27–45 years was inferred based on the cross-study analysis of qHPV vaccine immunogenicity demonstrating non-inferior HPV6/11/16/18 antibody responses in men aged 27–45 years versus 16–26 years. In conclusion, durable effectiveness of the qHPV vaccine was demonstrated in women 27–45 years of age, and vaccine efficacy was inferred in men 27–45 years of age based on the serological results.

Prevalence and Genotype Distribution of Human Papillomavirus Among Attendees at a Sexually Transmitted Diseases Clinic in Urban Tianjin, China

Background

Human papillomavirus (HPV) is linked to various cancers in males and females. The prevalence and genotype distribution of HPV vary depending on geographical region and the immunity provided by vaccines. Investigation of HPV epidemiology is of great meaning for the development of prevention programs.

Methods

From January 2017 to September 2019, using PCR-reverse dot blot hybridisation, we determined the HPV subtypes in 2801 patients 17-89 years old at the sexually transmitted diseases (STD) clinic of Tianjin Medical University General Hospital.

Results

The HPV infection rate was 50.79% in males and 50.64% in females. The most common HPV genotype in males and females was HPV6 (30.15% and 30.43%), followed by HPV16 (18.76% and 20.65%) and HPV11 (14.61% and 15.67%). Infection with a single HPV subtype predominated in both males and females, and the rate in males was higher than in females. By contrast, the rate of high-risk HPV (hrHPV) and low-risk HPV (lrHPV) mixed infection in females was higher than in males. Most HPV-positive patients were 20-39 years of age. The prevalence of infection with only hrHPV differed among the age groups; the peak age was 50 to 59 years.

Conclusion

The HPV prevalence was higher among the STD clinic outpatients than the general population. Therefore, a large-scale survey of high-risk populations is needed. It is anticipated that HPV vaccines, regular education and physical examinations may have a significant impact on the prevention of HPV-related diseases in high-risk groups.

Directionality of Genital Human Papillomavirus Infection Transmission Within Heterosexual Couples: A Systematic Review and Meta-analysis

BACKGROUND

Limited evidence indicates greater female-to-male (F-M) transmission of genital infection with human papillomavirus (HPV) relative to male-to-female (M-F). We verified the hypothesis of a differential transmission rate in couple-based studies by conducting a systematic review and meta-analysis.

METHODS

We searched MEDLINE, EMBASE, Scopus, and Cochrane Library databases for studies published until December 2019. We calculated pooled estimates of F-M and M-F transmission rates and their rate differences per 100 person-months, with 95% confidence intervals (CI), using a random-effects model. We counted occurrences of directionality preponderance for each HPV type.

RESULTS

We identified 7 eligible studies published between 2008 and 2019, providing data for 752 couples. Pooled estimates for F-M and M-F transmission rates were 3.01 (95% CI, 1.19-7.64; I2 = 97%) and 1.60 (95% CI, 0.86-2.98; I2 = 89%), respectively. The overall rate difference was 0.61 (95% CI, -0.27 to 1.49; I2 = 75%). Three studies provided rates by sex and HPV genotype; 2 favored a preponderance of F-M and 1 favored M-F transmission.

CONCLUSIONS

There was slight evidence for a differential transmission rate favoring higher F-M than M-F transmission with substantial statistical heterogeneity across studies.

Prevalence, Incidence, and Clearance of Human Papillomavirus Types Covered by Current Vaccines in Men With Human Immunodeficiency Virus in the SUN Study

BACKGROUND

High-risk anal human papillomavirus (HPV) infection is prevalent among men living with human immunodeficiency virus (HIV); the association between 9-valent (9v) high-risk HPV (HR-HPV) vaccine types and abnormal cytology has not been well characterized.

METHODS

We followed a prospective cohort study of persons with HIV at 7 HIV clinics in 4 US cities from March 2004 through June 2012. Annually, providers collected separate anal swabs for HPV detection and cytopathologic examination. Among men, we examined prevalence, incidence, and clearance of 9v HR-HPV vaccine types, compared with other HR types, and associations with abnormal cytology to assess potential vaccine impact.

RESULTS

Baseline prevalence of any anal 9v HR-HPV type among men who have sex with men (MSM) and men who have sex with women (MSW) was 74% and 25% (P < .001), respectively. Among 299 MSM, abnormal cytology was detected in 161 (54%) MSM and was associated with the presence of any 9v HR-HPV (relative risk [RR], 1.8 [95% confidence interval {CI}, 1.3-2.6]; P < .001). Among 61 MSW, abnormal anal cytology was detected in 12 (20%) and was associated with the presence of any 9v HR-HPV (RR, 4.3 [95% CI, 1.6-11.5]; P < .001).

CONCLUSIONS

Among men with HIV, the prevalence of the 7 HR-HPV types in the 9v vaccine was high and was associated with abnormal cytology. These findings indicate that men with HIV could benefit from prophylactic administration of the 9v HPV vaccine.

Comparison between anal cytology, high-resolution anoscopy and HPV DNA genotyping by polymerase chain reaction in the post-treatment follow-up of condylomata acuminata

AIM

to evaluate the presence of subclinical HPV-induced anal lesions with anal cytology, High-Resolution Anoscopy (HRA) and HPV genotyping by polymerase chain reaction (PCR) in the follow-up of treated condylomata acuminata (CA).

METHODS

seventy-nine male patients were included. One month after anal CA eradication, the patients underwent brush samples collection for anal cytology and PCR, and HRA with biopsy of acetowhite lesions. These methods were compared within all patients and between groups, according to Human Immunodeficiency Virus (HIV) infection status: HIV-negative; HIV-positive with TCD4 count above and below 350 cells/mm3.

RESULTS

the most frequent HPV types were 6 and 16. HPV DNA was isolated in 92%. HIV infection was associated with a higher number of oncogenic HPV types (p=0.038). All patients with negative PCR had negative HRA and cytology. There were no differences in cytological, HRA or histopathological findings between groups.

CONCLUSION

the association of the findings of cytopathology, HRA and genotyping of HPV refined the diagnosis of HPV-induced lesions. The degree of immunodeficiency was not associated with increase in remnant HPV-induced anal lesions.

[The consensus of the Portuguese Society of Andrology, Sexual Medicine and Reproduction on Male HPV: diagnosis]

HPV infection affects about 50% of sexually active individuals at least once in a lifetime. Diagnosis is made on careful inspection of the genital area and can be divided into benign lesions (genital warts or condyloma acuminatum) and pre-malignant lesions (intraepithelial neoplasia) that can lead to cancer (invasive neoplasia). Diagnostic recommendations are reviewed in Male, Female, Couple and in the immunocompromised host. Recent histological concepts are also discussed.

Estimating incidence rates of grouped HPV types: A systematic review and comparison of the impact of different epidemiological assumptions

BACKGROUND

Some studies on human papillomavirus (HPV) provide not only type-specific incidence rates (IR), but also IRs of HPV groupings (e.g. the nonavalent grouping). We made an inventory of the different approaches used to calculate such IRs and assessed their impact on the estimated IRs of HPV groupings.

METHODS

We performed a systematic review assessing all approaches used in literature to estimate IRs. Subsequently we applied these approaches to data of a Dutch cohort study on HPV in men who have sex with men (H2M). IRs were estimated for six different HPV groupings.

RESULTS

The systematic review yielded six different approaches (A-F) for estimating the IRs, varying in exclusion criteria at baseline, and the definitions of an incident event and person-time. Applying these approaches to the H2M dataset (n = 749), we found differences in the number of participants at risk, number of incidents events, person-time, and IR. For example, for the nonavalent grouping, depending on the approach chosen, the IR varied between 3.09 and 6.54 per 100 person-months.

CONCLUSION

In published studies different epidemiological assumptions are used to estimate IRs of grouped HPV types, leading to widely differing estimates of IRs. IRs between different studies may therefore not be comparable.

Untangling the dynamics of persistence and colonization in microbial communities

A central goal of community ecology is to infer biotic interactions from observed distributions of co-occurring species. Evidence for biotic interactions, however, can be obscured by shared environmental requirements, posing a challenge for statistical inference. Here, we introduce a dynamic statistical model, based on probit regression, that quantifies the effects of spatial and temporal covariance in longitudinal co-occurrence data. We separate the fixed pairwise effects of species occurrences on persistence and colonization rates, a potential signal of direct interactions, from latent pairwise correlations in occurrence, a potential signal of shared environmental responses. We first validate our modeling framework with several simulation studies. Then, we apply the approach to a pressing epidemiological question by examining how human papillomavirus (HPV) types coexist. Our results suggest that while HPV types respond similarly to common host traits, direct interactions are sparse and weak, so that HPV type diversity depends largely on shared environmental drivers. Our modeling approach is widely applicable to microbial communities and provides valuable insights that should lead to more directed hypothesis testing and mechanistic modeling.

Prevalence and Incidence of Anal and Cervical High-Risk Human Papillomavirus (HPV) Types Covered by Current HPV Vaccines Among HIV-Infected Women in the SUN Study

Background

Nonavalent (9v) human papilloma virus vaccine targets high-risk human papillomavirus (HR-HPV) types 16, 18, 31, 33, 45, 52, 58, and low-risk 6, 11. We examined prevalence, incidence, and clearance of anal and cervical HR-HPV in HIV-infected women.

Methods

The SUN Study enrolled 167 US women in 2004-2006. Anal and cervical specimens were collected annually for cytology and identification of 37 HPV types: 14 HR included: 9v 16, 18, 31, 33, 45, 52, 58; non-9v 35, 39, 51, 56, 59, 66, 68.

Results

Baseline characteristics of 126 women included: median age 38 years; 57% non-Hispanic black; 67% HIV RNA < 400 copies/mL; 90% CD4 counts ≥200 cells/mm3. HPV prevalence at anus and cervix was 90% and 83%; for 9v HR-HPV types, 67% and 51%; non-9v HR-HPV, 54% and 29%, respectively. The 9v and non-9v HR-HPV incidence rates/100 person-years were similar (10.4 vs 9.5; 8.5 vs 8.3, respectively); 9v clearance rates were 42% and 61%; non-9v 46% and 59%, in anus and cervix, respectively.

Conclusions

Anal HR-HPV prevalence was higher than cervical, with lower clearance; incidence was similar. Although prevalence of non-9v HR-HPV was substantial, 9v HR-HPV types were generally more prevalent. These findings support use of nonavalent vaccine in HIV-infected women.

Characteristics of HPV-unvaccinated undergraduate health students in Switzerland, a cross sectional study

Background

Human Papillomavirus (HPV) vaccination, intended for young women aged 11-14 years old, has been introduced in Switzerland in 2007. Ten years after its introduction, only a few studies have explored the reasons associated with uptake and non-uptake of the vaccination. Our objective was to identify the sociodemographic characteristics of a population of vaccinated and unvaccinated undergraduate healthcare female students, to define the reasons of non-uptake of vaccination, and compare our findings with those found in other Swiss cantons.

Methods

Between January and November 2017, women studying in Health Sciences School and Medical School in Geneva, aged 18-31 years old, were recruited in a large trial assessing HPV prevalence. As part of a smaller, observational study nested in this larger trial, women were invited to complete a questionnaire. Self-reported HPV vaccination uptake or non-uptake, as well as knowledge and attitude about HPV vaccination were assessed. T-Test and Chi square test were used to compare characteristics of vaccinated and unvaccinated women.

Results

Overall, 409 women were recruited in the study. The majority of them (69.1%) reported having been vaccinated for HPV, while 30.9% of them had never received any dose of the HPV vaccine. The only factor associated with a higher vaccination rate was the participants' origin, as women from Geneva were more represented in the vaccinated group than women from other Swiss regions or countries. Unvaccinated women were more likely to consider HPV vaccination as less important than the vaccinated ones (50.4% vs 3.5% p < 0.001).

Conclusion

Although no typical profile can be established in this studied population of unvaccinated women, a lack of information was a major reason of non-uptake of vaccination among the study participants. An effort by health authorities and carefully designed messages are essential to increase the population's awareness over cervical cancer and its prevention.

Trial registration

The trial was registered under cliniclatrials.gov with the identifier: NCT03474211.

Modeling HPV vaccination scale-up among urban young men who have sex with men in the context of HIV

INTRODUCTION

Young men who have sex with men (YMSM) are at high risk to contract human papillomavirus (HPV). While an effective vaccination exists, its use among YMSM is markedly lower compared to non-MSM and women. This study compares scaling up HPV vaccination in conjunction with other prevention strategies.

METHODS

An agent-based model of urban YMSM (≤26 years of age) reflective of the demography of Philadelphia, PA, simulated for up to ten years of follow-up to examine anal and oral transmission of the HPV genotypes covered in the nonavalent (9v) vaccine: 6, 11, 16, 18, 31, 33, 45, 52, 58. Starting HPV prevalences ranged from a high of 18% (type 6) to a low of 6% (type 31); overall 65% of individuals carried any HPV genotype. Simulated levels of vaccination were ranged from 0% to 13% (present-day level), 25%, 50%, 80% (Healthy People 2020 target), and 100% in conjunction with condom use and HIV seroadaptive practices. The primary outcome was the relative reduction in HPV infection.

RESULTS

Compared to present-day vaccination levels (13%), scaling-up vaccination led to expected declines in 10-year post-simulation HPV prevalence. Anal HPV (any 9v types) declined by 9%, 27%, 46%, and 58% at vaccination levels of 25%, 50%, 80%, and 100%, respectively. Similarly, oral HPV (any 9v types) declined by 11%, 33%, 57%, and 71% across the same levels of vaccine uptake. Comparing the prevention strategies, condoms blocked the greatest number of anal transmissions when vaccination was at or below present-day levels. For oral transmission, vaccination was superior to condom use at all levels of coverage.

CONCLUSIONS

Public health HPV preventions strategies should continue to emphasize the complementary roles of condoms and vaccination, especially for preventing oral infection. Improving vaccination coverage will ultimately have the greatest impact on reducing HPV infection among YMSM.

Acquisition, Persistence, and Clearance of Human Papillomavirus Infection Among Male Virgins Residing in Brazil, Mexico, and the United States

Background

Little is known about the natural history of human papillomavirus (HPV) infection in male virgins. This study estimated the incidence and clearance of genital HPV infection and the factors associated with these measures among men who denied at baseline ever having penetrative sex.

Methods

A cohort of 4123 men residing in Brazil, Mexico, and the United States were followed every 6 months for up to 10 visits. Genital exfoliated cells were collected and genotyped for 36 HPV types. Eighty-seven men were classified as virgins and included for analysis. Cox proportional hazards models identified factors associated with the incidence and clearance of genital HPV infection.

Results

The incidence rates for any HPV infection among virgins who did and those who did not initiate sex during follow-up were 26.2 and 14.6 cases/1000 person-months, respectively. After penetrative sex initiation, 45.5% of men acquired HPV within 24 months. Younger age, current smoking, no recent female sex partners, and prevalent HPV infection were associated with high-risk HPV clearance.

Conclusion

Virgins who did not initiate sex during follow-up still acquired HPV infection, possibly through nonpenetrative sexual contact. Further prospective cohort studies are needed to better understand factors associated with HPV acquisition and clearance in male virgins and recent nonvirgins.

Human Papillomavirus and Genital Disease in Men: What We Have Learned from the HIM Study

It is currently recognized that in addition to the major impact of human papillomavirus (HPV) infection in females, HPV causes considerable disease in men at the genitals, anal canal, and oropharynx. Specifically, genital HPV infections may progress to genital warts and penile carcinoma. Although studies concerning the natural history of HPV infections and associated neoplasias have mainly focused on women, during the last 2 decades considerable attention has been given in further understanding these infections in men. The HIM (HPV infection in men) Study, the only prospective multicenter study of male HPV natural history, consisted of a large prospective international cohort study in which men from Brazil, the United States, and Mexico were enrolled. The design and protocols of this study allowed unraveling crucial information regarding the relationship between HPV infection and clinical consequences in men, and associated risk factors at each of the anatomic sites where HPV is known to cause cancer in men.

Predicting Human miRNA-like Sequences within Human Papillomavirus Genomes

BACKGROUND

This study presents a prediction of putative miRNA within several Human Papillomavirus (HPV) types by using bioinformatics tools and a strategy based on sequence and structure alignment. Currently, little is known about HPV miRNAs.

METHODS

Computational methods have been widely applied in the identification of novel miRNAs when analyzing genome sequences. Here, ten whole-genome sequences from HPV-6, -11, -16, -18, -31, -33, -35, -45, -52, and -58 were analyzed. Software based on local contiguous structure-sequence features and support vector machine (SVM), as well as additional bioinformatics tools, were utilized for identification and classification of real and pseudo microRNA precursors.

RESULTS

An initial analysis predicted 200 putative pre-miRNAs for all the ten HPV genome variants. To derive a smaller set of pre-miRNAs candidates, stringent validation criteria was conducted by applying <‒10 ΔG value (Gibbs Free Energy). Thus, only pre-miRNAs with total scores above the cut-off points of 90% were considered as putative pre-miRNAs. As a result of this strategy, 19 pre-miRNAs were selected (hpv-pre-miRNAs). These novel pre-miRNAs were located in different clusters within HPV genomes and some of them were positioned at splice regions. Additionally, the 19 identified pre-miRNAs sequences varied between HPV genotypes. Interestingly, the newly identified miRNAs, 297, 27b, 500, 501-5, and 509-3-5p, were closely implicated in carcinogenesis participating in cellular longevity, cell cycle, metastasis, apoptosis evasion, tissue invasion and cellular growth pathways.

CONCLUSIONS

The novel putative miRNAs candidates could be promising biomarkers of HPV infection and furthermore, could be targeted for potential therapeutic interventions in HPV-induced malignancies.

Challenges of Human Papillomavirus Infection and Associated Diseases in Low-Resource Countries

Context.—

The prevalence of human papillomavirus (HPV) infection varies worldwide. The high-risk viruses are usually associated with cancers of the cervix, vagina, and vulva in women, cancer of the penis in men, and cancers of the anus, tonsils, oropharynx, and base of the tongue in both sexes.

Objectives.—

To review literature about the challenges and burden associated with HPV infection in low-resource (ie, developing) countries, focusing on sub-Saharan Africa. To review the prevention, incidence, prevalence, morbidity, and mortality of HPV infections in sub-Saharan Africa. To review the therapy and management of HPV infections in low-resource countries in comparison to developed countries.

Data Sources.—

Peer-reviewed literature and experience of some of the authors.

Conclusions.—

Sub-Saharan Africa has high HPV infection prevalence rates, with predominance of high-risk subtypes 16, 18, and 45. The difficulty of access to health care has led to higher morbidity and mortality related to HPV-related cancers. Improvement in screening programs will help in monitoring the spread of HPV infections. Survival studies can be more informative if reliable cancer registries are improved. HPV vaccination is not yet widely available and this may be the key to curtailing the spread of HPV infections in resource-poor countries.

Prevalence of anogenital HPV infection, related disease and risk factors among HIV-infected men in inner-city Johannesburg, South Africa: baseline findings from a cohort study

BACKGROUND

Persistent high-risk human papillomavirus (HR-HPV) infection is associated with the development of anogenital cancers, particularly in men living with HIV (MLWH). We describe the prevalence of anogenital HPV infection, abnormal anal cytology and anogenital warts (AGWs) in MLWH in Johannesburg, and explore whether HPV infection and receipt of antiretroviral treatment is associated with detection of abnormal anal cytology and AGWs.

METHODS

We enrolled a cohort of 304 sexually-active MLWH ≥18 years, who completed a questionnaire and physical examination. Genital swabs were collected from all men and intra-anal swabs from 250 (82%). Swabs were tested for HPV DNA and genotypes, and anal smears graded using the Bethesda classification. Factors associated with anogenital disease were assessed by logistic regression models.

RESULTS

Two thirds were receiving antiretroviral treatment, for a median 33 months (IQR = 15-58) and 54% were HIV-virologically suppressed. Only 5% reported ever having sex with men. Among 283 genital swabs with valid results, 79% had any HPV, 52% had HR-HPV and 27% had >1 HR-HPV infection. By comparison, 39% of the 227 valid intra-anal swabs had detectable HPV, 25% had any HR-HPV and 7% >1 HR infection. While most anal smears were normal (51%), 20% had ASCUS and 29% were LSIL. No cases had HSIL or cancer. Infection with >1 HR type (adjusted OR [aOR] = 2.39; 95%CI = 1.02-5.58) and alpha-9 types (aOR = 3.98; 95%CI = 1.42-11.16) were associated with having abnormal cytology. Prevalence of AGWs was 12%. Infection with any LR type (aOR = 41.28; 95%CI = 13.57-125.62), >1 LR type (aOR = 4.14; 95%CI = 1.60-10.69), being <6 months on antiretroviral treatment (aOR = 6.90; 95%CI = 1.63-29.20) and having a CD4+ count <200 cells/μL (aOR = 5.48; 95%CI: 1.60-18.78) were associated with having AGWs.

CONCLUSIONS

In this population, anogenital HR-HPV infection and associated low-grade disease is common, but severe anal dysplasia was not detected. Findings reinforce the need for HPV vaccination in men for preventing both AGWs and HR-HPV infection. Given the absence of anal HSILs, however, the findings do not support the use of anal screening programmes in this population.