Cervical human papillomavirus (HPV) infection in South African women: implications for HPV screening and vaccine strategies

Mapping the HPV Landscape in South African Women: A Systematic Review and Meta-Analysis of Viral Genotypes, Microbiota, and Immune Signals

This systematic review and meta-analysis evaluate human papillomavirus (HPV) prevalence, genotype distribution, and associations with cervicovaginal microbiota and cytokine profiles among South African women, where cervical cancer ranks as the second most common cancer. PubMed, SCOPUS, and Web of Science were searched for studies on HPV infection up to 21 September 2024. The pooled prevalence was estimated using a random-effects model, with subgroup analyses by province, sample type, and HIV status. Publication bias was evaluated using funnel plots and Egger's test. Of the 19,765 studies screened, 120 met the inclusion criteria, comprising 83,266 participants. Results indicate a high HPV burden, with a pooled prevalence of 58% (95% CI: 52-64%), varying regionally from 53% (95% CI: 41-65%) to 64% (95% CI: 55-73%), with some regions under-researched. Cervical samples had the highest HPV prevalence (60% (95% CI: 54-66%)), while non-genital samples were less studied. High-risk (HR) HPV types, notably HPV 16 (7.5%), HPV 35 (4.1%), and HPV 18 (3.9%), were prominent, with HPV 35 emphasizing the need for expanded vaccine coverage. HIV-positive women had a higher pooled HPV prevalence (63% (95% CI: 55-71%)). Funnel plot analysis and Egger's test suggested a potential publication bias (p = 0.047). HPV-positive women exhibited lower Lactobacillus levels and an increase in Bacterial Vaginosis (BV)-associated species like Gardnerella, potentially supporting HPV persistence. Cytokine analysis showed elevated MIP-1α and MIP-1β in HPV infections, though cytokine profiles may depend on HPV genotypes. These findings underscore the need for research on HPV-microbiome-immune interactions and call for comprehensive HPV-prevention strategies, including vaccines targeting regional HPV types and tailored interventions for HIV-positive populations.

FOXP3 serum concentration; a likely predictor of CIN and cervical cancer: Secondary analysis from a case control study at a clinic in South western Uganda

Biomarkers including Forkhead/winged-helix transcription factor box P3 have been proposed in immunohistochemical techniques to diagnose cervical lesions, but can be objectively quantified and measured in blood using methods that can be standardised. In this study we quantified the serum FOXP3 concentrations and assessed their association with cervical lesions at the cervical cancer clinic of Mbarara Regional Hospital (MRRH) Southwestern Uganda. We performed secondary analysis on archived serum samples from a previous unmatched case control study in which we recruited 90 cervical cancer (CC) cases, 90 cervical intraepithelial neoplasia (CIN) cases before any form of treatment and 90 controls. Clinical and demographic data were recorded. We measured FOXP3 concentrations using quantitative ELISA. We performed descriptive statistics and logistic regression in STATA 17 and took P-values of < 0.05 as statistically significant. The mean concentration of FOXP3 was higher in serum samples from CC cases compared with CIN cases and controls, and this difference was statistically significant (P value < 0.001). More than half (52/90,58 %) of serum samples from CC cases had FOXP3 concentrations greater than 0.0545 ng/ml (P value < 0.001). Increase serum FOXP3 expression was not associated with CIN. Increase in serum FOXP3 concentrations were observed to increase the chances of CC by 2 times (OR: 2.094, P value 0.038, 95 % CI: 1.042---4.209). Serum FOXP3 is likely associated with cervical lesions especially CC in our study population. Serum FOXP3 testing may be useful in resource limited settings to aid detection of such lesions given the challenges associated with cytology and VIA. We recommend diagnostic utility studies for circulating FOXP3 as a biomarker for detection of cervical cancer.

Prevalence and Risk Factors of Genital Human Papillomavirus Infections among Women in Lagos, Nigeria

Regional variations exist in HPV prevalence worldwide despite reports of high prevalence rates among African women. Limited data on genital HPV prevalence necessitated this study with the aim of determining the prevalence of genital HPV and associated risk factors among women in Lagos, Nigeria. Exfoliated cervical cells were collected with consent from 165 women using a cervical brush. Viral DNA was extracted and amplified by nested PCR using two sets of consensus primers (MY09/11 and GP5+/6+). An unconditional logistic regression model was used to identify predictors of HPV positivity. The HPV prevalence was 81.82% in all women and 87.59% in women with normal cytology. The risk of HPV infection was significantly increased among women who had a history of STI (odds ratio (OR) 3.94; 95% confidence interval (CI): 1.51-10.25, p = 0.005) while there was a significantly reduced risk of HPV infection among those who used condoms (odds ratio (OR) 3.94; 95% confidence interval (CI): 0.18-0.91, p = 0.03). The HPV prevalence observed shows an increased transmission of the virus in Lagos, Nigeria. Therefore, there is a need for intense public awareness and the implementation of early detection tests, treatment, and vaccination to prevent an increase in cervical cancer cases in Lagos, Nigeria.

Prevalence and distribution of selected cervical human papillomavirus types in HIV infected and HIV uninfected women in South Africa, 1989-2021: A narrative review

Background

Human papillomavirus infection, a causative agent of cervical cancer, is of great concern, more so in populations with high HIV prevalence, such as South Africa.

Aim

This review aimed to examine the prevalence and distribution of selected cervical human papillomavirus (HPV) types in HIV infected and HIV uninfected women in South Africa.

Methods

PubMed and Web of Science databases were searched using key words. For data integrity, data was assessed by two authors independently. The study inclusion criteria comprised records on cervical HPV, HPV genotyping and HPV type distribution among South African women. Statistical analysis was performed using Social Science Statistics.

Results

Sixty-nine articles met the inclusion criteria for analysis. Data on cervical HPV prevalence and type distribution was available only for five of the nine provinces of South Africa. Only 4/69 studies used sequencing as an approach to identify HPV types. In a general population, HPV type 16 was the most frequent (8.80%), followed by types 35 (4.86%), 18 (4.14%), 58 and 52 with the frequency of 3.65% and 3.62%, respectively. Furthermore, the least frequent type was HPV 70 (0.74%). Both HIV infected and HIV uninfected populations had a higher prevalence of high-risk human papillomavirus (hrHPV) types 16, 18 and 35 than other HPV types; while HPV types 6, 11 and 70 were the least frequent types from these populations. Lastly, HPV 16 was the most predominant type among women with normal (2.03%) and abnormal cervical cytology (6.60%).

Conclusion

Expanding on HPV genotyping will improve the knowledge in patterns of HPV type distribution in South Africa that will further help in decision making to improve current diagnostics, and future vaccine development and assessment.

Human papillomavirus prevalence and risk factors among HIV-negative and HIV-positive women residing in rural Eastern Cape, South Africa

OBJECTIVES

To investigate the prevalence of high-risk (HR) human papillomavirus (HPV) and factors associated with HR-HPV infection among women from rural Eastern Cape, South Africa.

METHODS

HPV prevalence was determined by Hybrid Capture 2 assay in cervical specimens from 417 women aged ≥30 years (median 46 years) recruited from the community health clinic in the Eastern Cape.

RESULTS

HR-HPV prevalence was 28.5% (119/417), and HIV-positive women had significantly higher HR-HPV prevalence than HIV-negative women (40.6%, 63/155 vs 21.4%, 56/262, respectively; p = 0.001). HIV-positive status (odds ratio (OR) 2.52, 95% confidence interval (CI) 1.63-3.90), having ≥3 lifetime sexual partners (OR 2.12, 95% CI 1.16-3.89), having ≥1 sexual partner in the last month (OR 1.89, 95% CI 1.21-2.92), ≥4 times frequency of vaginal sex in the past 1 month (OR 2.40, 95% CI 1.32-4.35), and having a vaginal discharge currently/in the previous week (OR 2.13, 95% CI 1.18-3.85) increased the risk of HR-HPV infection. In the multivariate analysis, HIV positivity remained strongly associated with HR-HPV infection (OR 1.94, 95% CI 1.17-3.22).

CONCLUSIONS

Risk factors related to sexual behaviors play a significant role in HR-HPV infection in this population. This report will inform health policymakers on HPV prevalence and contribute to discussions on the use of HPV testing as the primary cervical cancer screening test in South Africa.

Prevalence of cervical cancer and pre-cancerous lesions among unscreened Women in Kumasi, Ghana

Ghana does not have a universal population-based cervical cancer screening program and there is very limited information about the distribution of cervical epithelial cell lesions. This study provides evidence that a moderately high prevalence of cervical cancer and precancerous lesions exists among unscreened women in Kumasi.The prevalence of cervical epithelial cell abnormalities among a cross-section of women attending cervical cancer screening for the first time in a suburb of Ghana from 2011 to 2014 was studied. Cervical smears were prepared and examined independently by 2 cytotechnologists and confirmed by a pathologist. Cervical lesions were classified according to the Bethesda System for cervical cytology 2001.Out of the 592 women for whom a Pap smear was available for evaluation, 555 (93.8%) were negative for intraepithelial lesion or malignancy. Eight women (1.4%) showed atypical squamous cells of undetermined significance (ASCUS), 9 (1.4%) low-grade squamous intraepithelial lesions, and 2 (0.3%) high-grade squamous intraepithelial lesions. A total of 15 (2.5%) smears were unsatisfactory for cervical cytology. Additionally, 3 women (0.5%) had squamous cell carcinoma, giving an overall rate of 3.7% for epithelial cell abnormalities.Cervical cancer and precursor epithelial cell abnormalities are common among women in Kumasi for a disease that can be prevented by early detection through routine screening and management. This study provides adequate background data to recommend the implementation of cervical cancer screening in all eligible women in Ghana.

hrHPV prevalence and type distribution in rural Zimbabwe: A community-based self-collection study using near-point-of-care GeneXpert HPV testing

Objectives:

High-risk human papilloma viruses (hrHPV) are the causative agents of cervical cancer, the leading cause of cancer deaths among Zimbabwean women. The objective of this study was to describe the hrHPV types found in Zimbabwe for consideration in cervical cancer screening and vaccination efforts.

Design and methods:

To determine hrHPV prevalence and type distribution in Zimbabwe we implemented a community-based cross-sectional study of self-collected cervicovaginal samples with hrHPV screening using near-point-of-care Cepheid GeneXpert HPV.

Results:

The hrHPV prevalence was 17% (112/643); 33% (41/123) vs. 14% (71/520) among HIV-1-positive and -negative participants, respectively (p = 2.3E-07). Typing via Xpert HPV showed very good overall agreement (77.2%, kappa = 0.698) with the Seegene Anyplex II HPV HR Detection kit. The most common types were HPV16, HPV18, HPV35, HPV52, HPV58, HPV68, HPV18, and HPV51, each of which appeared in 14–20% of infections. 37% (28/76) of women with positive cytology results (ASCUS+) had a type not included in the basic vaccine and 25% (19/76) had a type not currently in the nine-valent vaccine.

Conclusions:

hrHPV type distribution includes less common high-risk types in rural Zimbabwe. The distribution and carcinogenicity of hrHPV type distribution should be considered during screening assay design, program development, as well as vaccine distribution and design.

Costs and cost-effectiveness of LEEP versus cryotherapy for treating cervical dysplasia among HIV-positive women in Johannesburg, South Africa

Background

Cervical cancer incidence is significant in countries, such as South Africa, with high burdens of both HIV and human papillomavirus (HPV). Cervical cancer is largely preventable if dysplasia is diagnosed and treated early, but there is debate regarding the best approaches for screening and treatment, especially for low-resource settings. Currently South Africa provides Pap smears followed by colposcopic biopsy and LEEP if needed in its public health facilities. We estimated the costs and cost-effectiveness of two approaches for treating cervical intraepithelial neoplasia grade 2 or higher (CIN2+) among HIV-infected women, most of whom were taking antiretroviral treatment, at a public HIV treatment facility in Johannesburg, South Africa.

Methods

Method effectiveness was derived from an intention-to-treat analysis of data gathered in a clinical trial completed previously at the study facility. In the trial, women who were diagnosed with CIN2+ and eligible for cryotherapy were randomized to cryotherapy or LEEP. If women were CIN2+ at six months as determined via Pap smear and colposcopic biopsy, all women—regardless of their original treatment assignment—received LEEP. “Cure” was then defined as the absence of disease at 12 months based on Pap smear and colposcopic biopsy. Health service costs were estimated using micro-costing between June 2013 and April 2014. Capital costs were annualized using a discount rate of 3%. Two different service volume scenarios were considered, and results from an as-treated analysis were considered in sensitivity analysis.

Results

In total, 166 women with CIN2+ were enrolled (86 had LEEP; 80 had cryotherapy). At 12 months, cumulative loss to follow-up was 12.8% (11/86) for the LEEP group and 13.8% (11/80) for cryotherapy. Based on the unadjusted intention-to-treat analysis conducted for this economic evaluation, there was no significant difference in efficacy. At 12 months, 83.8% (95% CI 73.8–91.1) of women with CIN2+ at baseline and randomized to cryotherapy were free of CIN2+ disease. In contrast, 76.7% (95% CI 66.4–85.2) of women assigned to LEEP were free from disease. On average, women initially treated with cryotherapy were less costly per patient randomized at US$ 118.00 (113.91–122.10), and per case “cured” at US$ 140.90 (136.01–145.79). Women in the LEEP group cost US$ 162.56 (157.90–167.22) per patient randomized and US$ 205.59 (199.70–211.49) per case cured. In the as-treated analysis, which was based on trial data, LEEP was more efficacious than cryotherapy; however, the difference was not significant. Cryotherapy remained more cost-effective than LEEP in all sensitivity and scenario analyses.

Conclusions

For this cost-effectiveness analysis, using an intention-to-treat approach and taking into consideration uncertainty in the clinical and cost outcomes, a strategy involving cryotherapy plus LEEP if needed at six months was dominant to LEEP plus LEEP again at six months if needed for retreatment. However, compared to other studies comparing LEEP and cryotherapy, the efficacy results were low in both treatment groups–possibly due to the HIV-positivity of the participants. Further research is needed, but at present choosing the “right” treatment option may be less important than ensuring access to treatment and providing careful monitoring of treatment outcomes.

Comparison of Four Human Papillomavirus Genotyping Methods: Next-generation Sequencing, INNO-LiPA, Electrochemical DNA Chip, and Nested-PCR

Background

Human papillomavirus (HPV) infection causes cervical cancer, thus necessitating early detection by screening. Rapid and accurate HPV genotyping is crucial both for the assessment of patients with HPV infection and for surveillance studies.

Methods

Fifty-eight cervicovaginal samples were tested for HPV genotypes using four methods in parallel: nested-PCR followed by conventional sequencing, INNO-LiPA, electrochemical DNA chip, and next-generation sequencing (NGS).

Results

Seven HPV genotypes (16, 18, 31, 33, 45, 56, and 58) were identified by all four methods. Nineteen HPV genotypes were detected by NGS, but not by nested-PCR, INNO-LiPA, or electrochemical DNA chip.

Conclusions

Although NGS is relatively expensive and complex, it may serve as a sensitive HPV genotyping method. Because of its highly sensitive detection of multiple HPV genotypes, NGS may serve as an alternative for diagnostic HPV genotyping in certain situations.

Therapeutic vaccines for high-risk HPV-associated diseases

Cancer is the second leading cause of death worldwide, and it is estimated that Human papillomavirus (HPV) related cancers account for 5% of all human cancers. Current HPV vaccines are extremely effective at preventing infection and neoplastic disease; however, they are prophylactic and do not clear established infections. Therapeutic vaccines which trigger cell-mediated immune responses for the treatment of established infections and malignancies are therefore required. The E6 and E7 early genes are ideal targets for vaccine therapy due to their role in disruption of the cell cycle and their constitutive expression in premalignant and malignant tissues. Several strategies have been investigated for the development of therapeutic vaccines, including live-vector, nucleic acid, peptide, protein-based and cell-based vaccines as well as combinatorial approaches, with several vaccine candidates progressing to clinical trials. With the current understanding of the HPV life cycle, molecular mechanisms of infection, carcinogenesis, tumour biology, the tumour microenvironment and immune response mechanisms, an approved HPV therapeutic vaccine seems to be a goal not far from being achieved. In this article, the status of therapeutic HPV vaccines in clinical trials are reviewed, and the potential for plant-based vaccine production platforms described.

Expression of unique chimeric human papilloma virus type 16 (HPV-16) L1-L2 proteins in Pichia pastoris and Hansenula polymorpha

Cervical cancer is ranked the fourth most common cancer in women worldwide. Despite two prophylactic vaccines being commercially available, they are unaffordable for most women in developing countries. We compared the optimized expression of monomers of the unique HPV type 16 L1-L2 chimeric protein (SAF) in two yeast strains of Pichia pastoris, KM71 (Mut^s ) and GS115 (Mut⁺ ), with Hansenula polymorpha NCYC 495 to determine the preferred host in bioreactors. SAF was uniquely created by replacing the h4 helix of the HPV-16 capsid L1 protein with an L2 peptide. Two different feeding strategies in fed-batch cultures of P. pastoris Mut^s were evaluated: a predetermined feed rate vs. feeding based on the oxygen consumption by maintaining constant dissolved oxygen levels (DO stat). All cultures showed a significant increase in biomass when methanol was fed using the DO stat method. In P. pastoris the SAF concentrations were higher in the Mut^s strains than in the Mut⁺ strains. However, H. polymorpha produced the highest level of SAF at 132.10 mg L^-1 culture while P. pastoris Mut^s only produced 23.61 mg L^-1 . H. polymorpha showed greater potential for the expression of HPV-16 L1/L2 chimeric proteins despite the track record of P. pastoris as a high-level producer of heterologous proteins.

Prevalence and Risk Factors for Genital Human Papillomavirus Infections Among Women in Southwest Nigeria

There is a great variation in the prevalence of cervical HPV infection worldwide with some of the highest rates being found in African women. Early onset of sexual activity (≤ 15 age), multiparity and sexual promiscuity have been recognized as some of the significant risk factors for HPV infection. In Nigeria, there is scarcity of data on the degree of relationship between these factors and the prevalence of HPV infection. Thus, this study was designed to determine the prevalence of genital HPV infection with its potential risk factors among women in Southwest Nigeria. Cervical swab specimen was collected from 295 consenting women including those presenting for routine cervical cancer screening, STI clinic attendees and women who attended community based outreach programmes. Viral DNA was extracted from the swab samples using commercially available DNA extraction Kit and amplified by PCR using two set of consensus primers (PGMY09/11 and degenerate GP-E6/E7). Fifty-five samples were positive to HPV DNA giving a prevalence of 18.6%. Risk factors such as lack of formal education (P-value: 0.003), divorcee (P-value: 0.019), polygamy (P-value: 0.027), unemployment (P-value: 0.023), low income earnings (P-value: 0.018), younger age (<18years) at sexual debut (P-value: 0.039) and passive smoking (P-value: 0.017) were significantly associated with HPV infection. High HPV prevalence and associated risk factors observed in this study shows the continuous transmission of the virus in Southwest Nigeria. Hence, enlarged monitoring including intense public awareness and cervical cancer screening is urgently needed for prevention and control strategies.

High-risk human papillomavirus types in HIV-infected and HIV-uninfected young women in KwaZulu-Natal, South Africa: implications for vaccination

BACKGROUND

High-risk human papillomavirus (hr-HPV) infections and low-grade squamous intraepithelial lesions occur frequently in young women. The available vaccines cover up to seven hr-HPV genotypes (HPV16, HPV18, HPV31, HPV33, HPV45, HPV52 and HPV58) and two low-risk HPV types (HPV6 and HPV11). The objective of this study was to describe the hr-HPV genotypes present among HIV-uninfected and HIV-infected young women in rural high schools.

METHODS

Cervicovaginal lavages were obtained from sexually active young women recruited from high schools in KwaZulu-Natal (n = 1223). HPV testing was done by the polymerase chain reaction using GP5+/GP6 + primers and enzyme immunoassay. HIV testing was done using rapid test kits.

RESULTS

Of the 1223 cervicovaginal lavages, 301 (25%) were positive for hr-HPV. The HPV prevalence was higher in HIV infected (32.20%, 95% CI: 0.27-0.38) than in HIV-uninfected women (22.50%, 95% CI: 0.21-0.26), (p = .001). Similarly, multiple infections were slightly more common in HIV infected (59.32%) than in HIV-uninfected women (53.51%), (p = .37). The nine predominant genotypes in descending order were HPV types 16 (n = 99, 22.10%), 51 (n = 58, 12.91%), 18 (n = 56, 12.50%), 35 (n = 50, 11.10%), 33 (n = 47, 10.82%), 56 (n = 42, 9.31%), 45 (n = 34, 7.60%), 52 (n = 32, 7.14%) and 59 (n = 31, 6.91%). HPV 35, 51, 56 and 59 (40.62%), which are not covered by any vaccine, were among the most prevalent in the schools of KwaZulu-Natal.

CONCLUSION

Four of the most predominant high-risk HPV types in this region are not covered by the new nine-valent HPV vaccine.

Genotypic characterisation of human papillomavirus infections among persons living with HIV infection; a case-control study in Kumasi, Ghana

OBJECTIVES

The objective of this study is to describe the burden of human papillomavirus (HPV) infection among women living with HIV and non-infected women in Ghana.

METHODS

A case-control study was conducted involving 107 women living with HIV aged between 18 and 59 years (cases) and 100 non-HIV-infected apparently healthy women (controls) who were recruited from the Kumasi South Hospital, from July to December, 2014. Cervicovaginal swabs were taken from study participants to characterise 28 high- and low-risk HPV genotypes using a multiplex real-time PCR.

RESULTS

The overall mean age for the participants was 40.10 ± 9.76 years. The prevalence of high-risk (hr)-HPV genotypes was significantly higher among the cases than the controls (77.4% vs. 41.6%, P < 0.0001). Overall, HPV 58 and 54 were the most predominant high-risk (18.8%) and low-risk (15.0%) genotypes detected. The two most common hr-HPV genotype isolates were 58 (18.8%) and 35 (15.9%) with 58 being the most prevalent among age group 35-44 years compared with hr-HPV 16, 18, 35 and 45, found predominantly among 18-34 age group.

CONCLUSIONS

Significant variations exist in HPV genotypes among HIV-infected and uninfected women.

Costs and Cost Effectiveness of Three Approaches for Cervical Cancer Screening among HIV-Positive Women in Johannesburg, South Africa

Background

South Africa has high rates of HIV and HPV and high incidence and mortality from cervical cancer. However, cervical cancer is largely preventable when early screening and treatment are available. We estimate the costs and cost-effectiveness of conventional cytology (Pap), visual inspection with acetic acid (VIA) and HPV DNA testing for detecting cases of CIN2+ among HIV-infected women currently taking antiretroviral treatment at a public HIV clinic in Johannesburg, South Africa.

Methods

Method effectiveness was derived from a validation study completed at the clinic. Costs were estimated from the provider perspective using micro-costing between June 2013-April 2014. Capital costs were annualized using a discount rate of 3%. Two different service volume scenarios were considered. Threshold analysis was used to explore the potential for reducing the cost of HPV DNA testing.

Results

VIA was least costly in both scenarios. In the higher volume scenario, the average cost per procedure was US$ 3.67 for VIA, US$ 8.17 for Pap and US$ 54.34 for HPV DNA. Colposcopic biopsies cost on average US$ 67.71 per procedure. VIA was least sensitive but most cost-effective at US$ 17.05 per true CIN2+ case detected. The cost per case detected for Pap testing was US$ 130.63 using a conventional definition for positive results and US$ 187.52 using a more conservative definition. HPV DNA testing was US$ 320.09 per case detected. Colposcopic biopsy costs largely drove the total and per case costs. A 71% reduction in HPV DNA screening costs would make it competitive with the conservative Pap definition.

Conclusions

Women need access to services which meet their needs and address the burden of cervical dysplasia and cancer in this region. Although most cost-effective, VIA may require more frequent screening due to low sensitivity, an important consideration for an HIV-positive population with increased risk for disease progression.

Prevalence and predictors of Pap smear cervical epithelial cell abnormality among HIV-positive and negative women attending gynecological examination in cervical cancer screening center at Debre Markos referral hospital, East Gojjam, Northwest Ethiopia

BACKGROUND

Cervical cancer is the leading cause of cancer related death among women in developing countries. Cervical cancer is preceded by cervical surface epithelial cell abnormalities (ECA) which can be detected by Pap smear test. Simultaneous human papillomavirus and human immunodeficiency virus (HIV) infection increases cervical cancer. Data on the prevalence and predictors of ECA among women in Ethiopia is limited. Hence, we aimed to determine the prevalence and associated factors of ECA among women.

METHODS

A comparative cross-sectional study was conducted among HIV+ and HIV- women attending gynecological examination in cervical cancer screening center at the Debre Markos referral hospital. The study subjects were stratified by HIV status and systematic random sampling method was used to recruit study participants. Cervical smears were collected for Pap smear examination. Logistic regression analysis was employed to examine the possible risk factors of cervical ECA.

RESULTS

A total of 197 HIV+ and 194 HIV- women were enrolled in the study. The overall prevalence of cervical ECA was 14.1 % of which the prevalence of atypical squamous cells undetermined significance (ASCUS), low grade squamous intraepithelial lesion (SIL), high grade SIL, squamous cell carcinoma and ASC, cannot exclude high grade SIL (ASCH) were 5.1, 3.8, 4.1 and 1.0 %, 0.0 % respectively. Significantly higher prevalence of ECA (17.8 %) was observed among HIV+ women (COR 1.9, 95 % CI: 1.1 - 3.4, p = 0.036) as compared to HIV-women (10.3 %). Multiple sexual partnership (AOR 3.2, 95 % CI: 1.1 - 10.0, p = 0.04), early ages of first sexual contact (<15 years) (AOR 5.2, 95 % CI: 1.5 - 17.9, p = 0.009), parity greater than three (AOR 10.9, 95 % CI: 4.2 - 16.8, p < 0.001) and long term oral contraceptive pills (OCP) use (AOR 11.9, 95 % CI: 2.1 - 16.7, p = 0.02) were significant predictors of prevalence of ECA.

CONCLUSIONS

Cervical ECA is a major problem among HIV-infected women. Lower CD4+ T-cell counts of below 350 cells/μl, HIV infection, multiple sexual partnership, early age at first sexual contact, parity greater than three and long term OCP use were significant predictors of prevalence of ECA. Strengthening screening program in HIV+ women should be considered.

Human papillomavirus genotypes distribution by cervical cytologic status among women attending the General Hospital of Loandjili, Pointe-Noire, Southwest Congo (Brazzaville)

HPV infection is associated with cervical cancer, one of the major public health problems in developing countries. In the Republic of Congo, despite of the high age-standardized incidence rate estimated at 25.2 per 100,000 women, molecular epidemiology data on HPV infections are very limited. We investigated HPV genotypes distribution in cervical smears among patients attending the General Hospital of Loandjili, Southwest Congo. A cross-sectional hospital-based study was conducted on 321 women. Liquid-based cytology samples were collected for cytological diagnosis and HPV detection. Nested-PCR was performed using MY09/MY11 and GP5+/GP6+ primers with genotyping by direct sequencing. Type-specific PCR for HPV-6, -11, -16, -18, -31 and -33 was also used to assess multiple infections. Out of 321 women examined, 189 (58.8%) had normal cytology, 16 (5.0%) had ASCUS and 116 (36.1%) had cytological abnormalities. HPV-DNA was detected in 22 (11.6%), 6 (37.5%), and 104 (89.6%) normal cytology, ASCUS and cytological abnormalities respectively. HPV16 was the most prevalent genotype regardless of cytological status followed by HPV70 in women without lesions and HPV33 among those with lesions. HR-HPV prevalence varied significantly according to the cervical cytology (P = 0.000). Among women without lesions, two peaks of HPV infections were observed in age group less than 30 years (60.0%) and in age group 50-59 years (7.1%). Age, age of first sex, multiple sexual partners and pregnancies were the risk factors for HPV infection in women without lesions. Our findings could be used as evidence data base for future epidemiological monitoring in this region.

Prevalence of human papillomavirus genotypes among African women with normal cervical cytology and neoplasia: a systematic review and meta-analysis

BACKGROUND

Several meta-analyses confirmed the five most prevalent human papillomavirus (HPV) strains in women with and without cervical neoplastic diseases are HPV16, 18, 31, 52, and 58. HPV16/18 are the predominant oncogenic genotypes, causing approximately 70% of global cervical cancer cases. The vast majority of the women studied in previous analyses were from Europe, North America, Asia, and most recently Latin America and the Caribbean. Despite the high burden of cervical cancer morbidity and mortality in Africa, a robust meta-analysis of HPV genotype prevalence and distribution in African women is lacking.

METHODS AND FINDINGS

We systematically searched 14 major databases from inception to August 2013 without language restriction, following the Meta-Analysis of Observational Studies in Epidemiology and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Seventy-one studies from 23 African countries were identified after screening 1162 citations and data abstracted and study quality appraised from 195 articles. HPV type-specific prevalence and distribution was estimated from 17,273 cases of women with normal cervical cytology; 1019 women with atypical squamous cells of undetermined significance (ASCUS); 1444 women with low-grade squamous intraepithelial lesion (LSIL); 1571 women with high-grade squamous intraepithelial lesion (HSIL); and 4,067 cases of invasive cervical carcinoma (ICC). Overall prevalence of HPV16/18 were 4.4% and 2.8% of women with normal cytology, 12.0% and 4.4% with ASCUS, 14.5% and 10.0% with LSIL, 31.2% and 13.9% with HSIL, and 49.7% and 18.0% with ICC, respectively. Study limitations include the lack of adequate data from Middle and Northern African regions, and variations in the HPV type-specific sensitivity of different genotyping protocols.

CONCLUSIONS

To our knowledge, this study is the most comprehensive assessment of the overall prevalence and distribution of HPV genotypes in African women with and without different cervical neoplasias. We have established that HPV16/18 account for 67.7% of ICC cases among African women. Based on our findings, we highly recommend the administration of existing prophylactic vaccines to younger women not infected with HPV16/18 and an increase in HPV screening efforts for high-risk genotypes to prevent cervical cancer.

REVIEW REGISTRATION

International Prospective Register of Systematic Reviews CRD42013006558.

The genetic regulation of infant immune responses to vaccination

A number of factors are recognized to influence immune responses to vaccinations including age, gender, the dose, and quality of the antigen used, the number of doses given, the route of administration, and the nutritional status of the recipient. Additionally, several immunogenetic studies have identified associations between polymorphisms in genes encoding immune response proteins, both innate and adaptive, and variation in responses to vaccines. Variants in the genes encoding Toll-like receptors, HLA molecules, cytokines, and cytokine receptors have associated with heterogeneity of responses to a wide range of vaccines including measles, hepatitis B, influenza A, BCG, Haemophilus influenzae type b, and certain Neisseria meningitidis serotypes, amongst others. However, the vast majority of these studies have been conducted in older children and adults and there are very few data available from studies conducted in infants. This paper reviews the evidence to date that host genes influencing vaccines responses in these older population and identifies a large gap in our understanding of the genetic regulation of responses in early life. Given the high mortality from infection in early life and the challenges of developing vaccines that generate effective immune responses in the context of the developing immune system further research on infant populations is required.

The preliminary study of p53 codon 72 polymorphism and risk of cervical carcinoma in Gabonese women

Cervical cancer is the leading cause of cancer-related death in Africa and the first most common cancer in Gabonese women due to infection of high-risk human papillomavirus (HPV). However, other cofactors such as genetic factors also come into play. A common polymorphism of the p53 codon 72 in exon 4 with two alleles encoding arginine or proline is known at this locus. The homozygous arginine form of this polymorphism has been associated with the development of cervical cancer as an increased genetic risk factor. However, the results are still controversial. This study aims to investigate whether the genotype distribution of p53 codon 72 may be a risk factor for cervical cancer among Gabonese women. Samples from 102 Gabonese women, 31 diagnosed with cervical cancer and 71 healthy controls, were used. HPV detection was done by nested PCR with MY09/11 and GP5+/6+ primers followed by sequencing for HPV genotyping. p53 codon 72 polymorphism determination was performed by allele-specific PCR assay. Viral DNA was detected in 87.1 % of cases and in 54.93 % of control. HPV 16 was the most predominant in cancer and controls cases. The distribution of Arg/Arg, Arg/Pro and Pro/Pro genotypes was 35.5, 51.6 and 12.9 % in the cervical cancer group and 22.5, 62 and 15.5 % in the control group. No significant association was found between polymorphism of p53 itself as well as in combination with HPV16/18 infection and risk of development of cervical cancer among Gabonese women. Thus, the polymorphism of p53 codon 72 in exon 4 does not seem to play a role in the development of cervical cancer among Gabonese women.

The burden of human papillomavirus infections and related diseases in sub-saharan Africa

Despite the scarcity of high quality cancer registries and lack of reliable mortality data, it is clear that human papillomavirus (HPV)-associated diseases, particularly cervical cancer, are major causes of morbidity and mortality in sub-Saharan Africa (SSA). Cervical cancer incidence rates in SSA are the highest in the world and the disease is the most common cause of cancer death among women in the region. The high incidence of cervical cancer is a consequence of the inability of most countries to either initiate or sustain cervical cancer prevention services. In addition, it appears that the prevalence of HPV in women with normal cytology is higher than in more developed areas of the world, at an average of 24%. There is, however, significant regional variation in SSA, with the highest incidence of HPV infection and cervical cancer found in Eastern and Western Africa. It is expected that, due to aging and growth of the population, but also to lack of access to appropriate prevention services and the concomitant human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) epidemic, cervical cancer incidence and mortality rates in SSA will rise over the next 20 years. HPV16 and 18 are the most common genotypes in cervical cancer in SSA, although other carcinogenic HPV types, such as HPV45 and 35, are also relatively more frequent compared with other world regions. Data on other HPV-related anogenital cancers including those of the vulva, vagina, anus, and penis, are limited. Genital warts are common and associated with HPV types 6 and 11. HIV infection increases incidence and prevalence of all HPV-associated diseases. Sociocultural determinants of HPV-related disease, as well as the impact of forces that result in social destabilization, demand further study. Strategies to reduce the excessive burden of HPV-related diseases in SSA include age-appropriate prophylactic HPV vaccination, cervical cancer prevention services for women of the reproductive ages, and control of HIV/AIDS. This article forms part of a regional report entitled "Comprehensive Control of HPV Infections and Related Diseases in the Sub-Saharan Africa Region" Vaccine Volume 31, Supplement 5, 2013. Updates of the progress in the field are presented in a separate monograph entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Oxymatrine induces apoptosis in human cervical cancer cells through guanine nucleotide depletion

Oxymatrine is an alkaloid obtained primarily from Sophora roots and has been shown to show anticancer effects in various cancers. However, the cellular and molecular effects of this agent on cervical cancer have been poorly characterized. Here, we investigated the antitumor effect of oxymatrine on a human cervical cancer cell line (HeLa). Our results showed that application of oxymatrine significantly inhibited the cell growth and tumorigenesis in a dose-dependent manner and induced apoptosis through caspase-dependent pathways as determined using flow cytometry and TUNEL staining analysis. To define the proteins potentially related to the mechanisms of action, proteomic analysis was utilized to detect proteins altered by oxymatrine. As the downregulated gene, inosine monophosphate dehydrogenase type II (IMPDH2) was responsible for oxymatrine-induced mitochondrial-related apoptosis. Moreover, oxymatrine depleted intracellular guanosine 5'-triphosphate (GTP) levels by effective IMPDH inhibition. Functional analyses further showed that oxymatrine and tiazofurin, an inhibitor of IMPDH2, sensitized resistant HeLa/DDP cells to cisplatin. In addition, the expression of IMPDH2 in cervical cancer was significantly higher than that in the normal cervical epithelium. Taken together, these findings suggest that targeting of IMPDH2 by potential pharmacological inhibitors, oxymatrine in combination with chemotherapy, might be a promising means of overcoming chemoresistance in cervical cancer with high IMPDH2 expression, and may thus provide new insights into the mechanism of oxyamtrine-induced anticancer effects.

Concordant Oral-Genital HPV Infection in South Africa Couples: Evidence for Transmission

Objective: Cervical cancer is a leading cause of cancer mortality in South Africa. However, little is known about oral human papillomavirus (HPV) infection in high human immunodeficiency virus (HIV) seroprevalence settings.

Method: Thirty-four adult heterosexual couples attending an HIV testing center in Soweto, South Africa were enrolled. Each participant provided an oral rinse sample and genital swab, which were tested for 37 types of HPV DNA, and completed a risk behavior survey.

Results: Median age was 31 years and 9% (3/34) of men and 29% (10/34) of women enrolled tested HIV-positive; median CD4 count was 437 cells/mm³. Oral HPV prevalence was similar in women and men (12 vs. 18%, p = 0.48), and was non-significantly higher in HIV-infected vs. HIV-uninfected (23 vs. 13%, p = 0.34) subjects. Most men (82%) and women (84%) reported ever performing oral sex. Median number of lifetime sexual partners was “2–5” while median number of lifetime oral sex partners was 1. Oncogenic HPV subtypes were detected in 4% of oral, 26% of penile, and 74% of vaginal samples, including HPV16 in 1, 12, and 21% of these samples respectively. Genital HPV prevalence was significantly higher than oral HPV prevalence (75 vs. 15%, p ≤ 0.001). Thirty-five percent of couples (12/34) had at least one type-specific concordant vaginal-penile HPV infection but only one of nine couples with oral HPV had concordant oral–oral infection. However, 67% (4/6) of men and 25% (1/4) of women with oral HPV infection had partners with concordant genital HPV infection.

Implications and Impact: Oral–oral HPV concordance between couples is low, but oral-genital and genital–genital HPV concordance is higher, including concordance of male oral HPV infection with their partners’ vaginal HPV infection. This data is consistent with possible transmission of vaginal HPV infection to the oral cavity of sexual partners performing oral sex.

Immunogenic assessment of plant-produced human papillomavirus type 16 L1/L2 chimaeras

Cervical cancer is caused by infection with human papillomaviruses (HPV) and is a global concern, particularly in developing countries, which have ~80% of the burden. HPV L1 virus-like particle (VLP) type-restricted vaccines prevent new infections and associated disease. However, their high cost has limited their application, and cytological screening programmes are still required to detect malignant lesions associated with the nonvaccine types. Thus, there is an urgent need for cheap second-generation HPV vaccines that protect against multiple types. The objective of this study was to express novel HPV-16 L1-based chimaeras, containing cross-protective epitopes from the L2 minor capsid protein, in tobacco plants. These L1/L2 chimaeras contained epitope sequences derived from HPV-16 L2 amino acid 108-120, 56-81 or 17-36 substituted into the C-terminal helix 4 (h4) region of L1 from amino acid 414. All chimaeras were expressed in Nicotiana benthamiana via an Agrobacterium-mediated transient system and targeted to chloroplasts. The chimaeras were highly expressed with yields of ~1.2 g/kg plant tissue; however, they assembled differently, indicating that the length and nature of the L2 epitope affect VLP assembly. The chimaera containing L2 amino acids 108-120 was the most successful candidate vaccine. It assembled into small VLPs and elicited anti-L1 and anti-L2 responses in mice, and antisera neutralized homologous HPV-16 and heterologous HPV-52 pseudovirions. The other chimaeras predominantly assembled into capsomeres and other aggregates and elicited weaker humoral immune responses, demonstrating the importance of VLP assembly for the immunogenicity of candidate vaccines.

Human papillomavirus seropositivity and subsequent risk of HIV acquisition in rural South African women

OBJECTIVE

This study aimed to provide a population-based estimate of human papillomavirus (HPV) seropositivity for women in a rural African context and to evaluate the impact of HPV serostatus on subsequent acquisition of HIV outside a clinical setting.

DESIGN

A random sample of women participating in a longitudinal, population-based HIV survey combined with a case-control study.

METHODS

Blood samples of women participating in a single round of population-based HIV surveillance (N = 1049) in a rural South African population were used to measure vaccine-preventable HPV seropositivity (types 6, 11, 16, and 18) in the general population in 2010. Using results from the repeat HIV surveys, a case-control analysis was then performed comparing HPV sero-status in samples taken from HIV sero-converting women (prior to infection with HIV) against samples from HIV-uninfected, sexually-active controls matched 1:1 according to 5-year age band (377:377). Unconditional multivariable logistic regression with multiple imputations was used to control for sociodemographic and behavioral variables associated with HIV acquisition.

RESULTS

Human papillomavirus seropositivity in the population-based sample of women was 20.8% (95% confidence interval [CI], 18.3-23.4), and HIV prevalence was 27.6% (95% CI, 24.9-30.4). In the case-control analysis, allowing for variables known to be associated with HIV incidence, HPV seropositivity was associated with nearly 2.5 times the odds of subsequent acquisition of HIV (adjusted odds ratio, 2.33 [95% CI, 1.61-3.39]; P < 0.001).

CONCLUSIONS

These results suggest that HPV vaccination before or soon after sexual debut could lower HIV infection risk. Randomized trials that quantify the impact of HPV vaccination in girls on the risk of acquiring HIV are urgently required.

High Rate of Multiple Concurrent Human Papillomavirus Infections among HIV-Uninfected South African Adolescents

BACKGROUND

The epidemiology and impact of multiple concurrent Human papillomavirus (HPV) infections on the natural history of cervical disease is uncertain, but could have significant implications for cervical cancer prevention and HPV vaccination strategies.

METHODS

A cross-sectional prevalence study was conducted to determine the overall prevalence of HPV and the rate of multiple concurrent HPV infections, in a cohort of sexually active HIV-uninfected South African adolescents. HPV genotyping was performed using the polymerase chain reaction.

RESULTS

Overall prevalence of HPV was 64.1%. Multiple concurrent HPV infections were found in 43.6% of participants and 68% of HPV-infected participants. Non-vaccine high-risk HPV (HR-HPV) genotypes were found much more often than vaccine types (HPV16 and HPV18).

CONCLUSIONS

Our cohort of young South African females was found to have a high overall prevalence of HPV and multiple concurrent HPV infections. Most HR-HPV infections found were genotypes other than HPV16 or HPV18.

Distribution of high-risk human papillomavirus genotypes among HIV-negative women with and without cervical intraepithelial neoplasia in South Africa

OBJECTIVE

Large studies describing the profile of high-risk Human papillomavirus (hrHPV) genotypes among women in sub-Saharan Africa are lacking. Here we describe the prevalence and distribution of hrHPV genotypes among HIV-negative women in South Africa, with and without cervical intraepithelial neoplasia (CIN).

METHODS

We report data on 8,050 HIV-negative women, aged 17-65 years, recruited into three sequential studies undertaken in Cape Town, South Africa. Women had no history of previous cervical cancer screening. Cervical samples were tested for hrHPV DNA using the Hybrid Capture 2 (HC2) assay and all positive samples were genotyped using a PCR-based assay (Line Blot). Women underwent colposcopy and biopsy/endocervical curettage to determine CIN status. The prevalence and distribution of specific hrHPV genotypes were examined by age and CIN status.

RESULTS

Overall, 20.7% (95% CI, 19.9-21.6%) of women were hrHPV-positive by HC2, with women with CIN having the highest rates of positivity. Prevalence decreased with increasing age among women without CIN; but, a bimodal age curve was observed among women with CIN. HPV 16 and 35 were the most common hrHPV genotypes in all age and CIN groups. HPV 45 became more frequent among older women with CIN grade 2 or 3 (CIN2,3). Younger women (17-29 years) had more multiple hrHPV genotypes overall and in each cervical disease group than older women (40-65 years).

CONCLUSION

HPV 16, 35, and 45 were the leading contributors to CIN 2,3. The current HPV vaccines could significantly reduce HPV-related cervical disease; however, next generation vaccines that include HPV 35 and 45 would further reduce cervical disease in this population.

Next-generation sequencing of cervical DNA detects human papillomavirus types not detected by commercial kits

Background

Human papillomavirus (HPV) is the aetiological agent for cervical cancer and genital warts. Concurrent HPV and HIV infection in the South African population is high. HIV positive (+) women are often infected with multiple, rare and undetermined HPV types. Data on HPV incidence and genotype distribution are based on commercial HPV detection kits, but these kits may not detect all HPV types in HIV + women. The objectives of this study were to (i) identify the HPV types not detected by commercial genotyping kits present in a cervical specimen from an HIV positive South African woman using next generation sequencing, and (ii) determine if these types were prevalent in a cohort of HIV-infected South African women.

Methods

Total DNA was isolated from 109 cervical specimens from South African HIV + women. A specimen within this cohort representing a complex multiple HPV infection, with 12 HPV genotypes detected by the Roche Linear Array HPV genotyping (LA) kit, was selected for next generation sequencing analysis. All HPV types present in this cervical specimen were identified by Illumina sequencing of the extracted DNA following rolling circle amplification. The prevalence of the HPV types identified by sequencing, but not included in the Roche LA, was then determined in the 109 HIV positive South African women by type-specific PCR.

Results

Illumina sequencing identified a total of 16 HPV genotypes in the selected specimen, with four genotypes (HPV-30, 74, 86 and 90) not included in the commercial kit. The prevalence’s of HPV-30, 74, 86 and 90 in 109 HIV positive South African women were found to be 14.6%, 12.8%, 4.6% and 8.3% respectively.

Conclusions

Our results indicate that there are HPV types, with substantial prevalence, in HIV positive women not being detected in molecular epidemiology studies using commercial kits. The significance of these types in relation to cervical disease remains to be investigated.

Cervical human papillomavirus (HPV) infection and HPV type 16 antibodies in South African women

There is a high incidence of cervical cancer in South African women. No large studies to assess human papillomavirus virus (HPV) infection or HPV type 16 (HPV-16) exposure have occurred in the region, a requirement for policy making with regards to HPV screening and the introduction of vaccines. Control women (n = 1,003) enrolled in a case control study of hormonal contraceptives and cervical cancer were tested for 27 cervical HPV types by reverse line blot analysis. The seroprevalence of HPV-16 immunoglobulin G (IgG) and IgA antibodies was assessed by a virus-like particle-based enzyme-linked immunoassay of 908 and 904 control women, respectively, and of 474 women with cervical cancer. The cervical HPV prevalence was 26.1%. The HPV-16 IgG seroprevalence was 44.4% and the HPV-16 IgA seroprevalence was 28.7% in control women, and these levels were significantly higher (61.8% and 52.7%, respectively) for women with cervical cancer (odds ratio [OR], 2.1 and 2.8, respectively). The cervical HPV prevalence showed an association with cervical disease, and the HPV-16 IgG prevalence decreased while the HPV-16 IgA prevalence increased with increasing age (P < 0.05). The prevalence of oncogenic HPV types (including HPV-16) decreased with age, whereas nononcogenic HPV types showed limited association with age. Multivariate analysis revealed cervical HPV infection to be associated with herpes simplex virus type 2 infection (OR, 1.7) and increasing years of education (OR, 1.9). HPV-16 IgG antibodies were inversely associated with current smoking status (OR, 0.6), and the presence of HPV-16 IgA antibodies was inversely associated with the use of alcohol (OR, 2.1) and inversely associated with the use of oral contraceptives (OR, 0.6). High levels of exposure to HPV, and particularly HPV-16, were evident in this population. The apparent increase of serum HPV-16 IgA with increasing age requires further investigation.