The age-specific prevalence of human papillomavirus and risk of cytologic abnormalities in rural Nigeria: implications for screen-and-treat strategies

Human papillomavirus serotypes and determinants among women with invasive cervical cancer in Katsina state, Northwest-Nigeria: a multicentre study

Background

Cervical cancer is the leading cause of gynaecological cancer death among women in developing countries and the most preventable of all gynaecological cancers as its infectious aetiological agent, human papillomavirus (HPV), is known. The knowledge of HPV serotype distribution in a sub-region is key to the implementation of an appropriate HPV vaccination programme.

Aim

To assess the prevalence of HPV-DNA, serotypes and risk-determinants among women with invasive cervical cancer (ICC) in Katsina State, Northwestern Nigeria.

Methods

This was a cross-sectional, multicenter study involving Federal Teaching Hospital Katsina, General Hospital Katsina and Turai Yar'adua Maternal and Child Hospital Katsina, Nigeria. Sixty-three women with histologically confirmed cervical cancer who fulfilled the criteria were recruited into the study. Tissue blocks with a confirmed diagnosis of ICC were taken to DNA Labs Kaduna for HPV-deoxyribonucleotide acid detection and typing. An interviewer-administered questionnaire developed for the study was used to obtain socio-demographic, reproductive characteristics and the other risk factors for HPV acquisition and persistence.

Results

The HPV-positivity rate in ICC was 95.5% while the prevalence of high-risk HPV (Hr-HPV)-DNA in the specimen was 54.6% with 13 HPV-serotypes detected, 9 Hr-HPV types (16,18,31,33,35,45,51,56,82) and 4 low-risk HPV types (6,44,81,89). The most commonly detected HPV serotype among women with a single HPV infection was HPV 81 (40.9%) followed by HPV 16 (28.8%). However, HPV 16 was the most common serotype among those with multiple HPV infections. Prevalence of other detected serotypes were HPV 31 (24.2%), 33 (24.2%), HPV 18 (10.6%), HPV 35 (3.0%), HPV 45 (9.1%), HPV 44 (1.5%), HPV 51 (3.0%), HPV 56 (3.0%), HPV 82 (1.5%), HPV 89 (1.5%) and HPV 6 (1.5%). Forty-four out of 63 women (69.8%) had a single HPV infection, 19 (30.2%) had multiple HPV infections and 15 (24.3%) were co-infected with HPV 16/31/33. There was a statistically significant association between HPV 16 and squamous cell carcinoma (SCC).

Conclusion

The study demonstrates a prevalence of HPV-DNA as 95.5% among women with ICC. The most commonly detected HPV serotype was HPV 81 seen in 41% which was an uncommon finding. Furthermore, statistically significant associations between HPV serotypes 16 and 82 with SCC were detected.

Redesign of a rapid, low-cost HPV typing assay to support risk-based cervical screening and management

Accelerated cervical cancer control will require widespread human papillomavirus (HPV) vaccination and screening. For screening, sensitive HPV testing with an option of self-collection is increasingly desirable. HPV typing predicts risk of precancer/cancer, which could be useful in management, but most current typing assays are expensive and/or complicated. An existing 15-type isothermal amplification assay (AmpFire, Atila Biosystems, USA) was redesigned as a 13-type assay (ScreenFire) for public health use. The redesigned assay groups HPV types into four channels with differential cervical cancer risk: (a) HPV16, (b) HPV18/45, (c) HPV31/33/35/52/58 and (d) HPV39/51/56/59/68. Since the assay will be most useful in resource-limited settings, we chose a stratified random sample of 453 provider-collected samples from a population-based screening study in rural Nigeria that had been initially tested with MY09-MY11-based PCR with oligonucleotide hybridization genotyping. Frozen residual specimens were masked and retested at Atila Biosystems. Agreement on positivity between ScreenFire and prior PCR testing was very high for each of the channels. When we simulated intended use, that is, a hierarchical result in order of clinical importance of the type groups (HPV16 > 18/45 > 31/33/35/52/58 > 39/51/56/59/68), the weighted kappa for ScreenFire vs PCR was 0.90 (95% CI: 0.86-0.93). The ScreenFire assay is mobile, relatively simple, rapid (results within 20-60 minutes) and agrees well with reference testing particularly for the HPV types of greatest carcinogenic risk. If confirmed, ScreenFire or similar isothermal amplification assays could be useful as part of risk-based screening and management.

The pattern of human papillomavirus infection and genotypes among Nigerian women from 1999 to 2019: a systematic review

BACKGROUND

There are no robust national prevalence of Human Papillomavirus (HPV) genotypes in Nigerian women despite the high burden of cervical cancer morbidity and mortality.

THE OBJECTIVE OF STUDY

This study aims to determine the pooled prevalence and risk factors of genital HPV infection in Nigeria through a systemic review protocol.

METHODS

Databases including PubMed, Scopus, Google Scholar and AJOL were searched between 10 April to 28 July 2020. HPV studies on Nigerian females and published from April 1999 to March 2019 were included. GRADE was used to assess the quality of evidence.

RESULTS

The pooled prevalence of cervical HPV was 20.65% (95%CI: 19.7-21.7). Genotypes 31 (70.8%), 35 (69.9%) and 16 (52.9%) were the most predominant HPV in circulation. Of the six geopolitical zones in Nigeria, northeast had the highest pooled prevalence of HPV infection (48.1%), while the least was in the north-west (6.8%). After multivariate logistic regression, duration (years) of sexual exposure (OR = 3.24, 95%CI: 1.78-9.23]), history of other malignancies (OR = 1.93, 95%CI: 1.03-2.97]), history of sexually transmitted infection (OR = 2.45, 95% CI: 1.31-3.55]), coital frequency per week (OR = 5.11, 95%CI: 3.86-14.29), the status of circumcision of the sexual partner (OR = 2.71, 95%CI: 1.62-9.05), and marital status (OR = 1.72, 95%CI: 1.16-4.72), were significant risk factors of HPV infection (p < 0.05). Irregular menstruation, post-coital bleeding and abdominal vaginal discharge were significantly associated with HPV infection (p < 0.05).

CONCLUSION

HPV prevalence is high in Nigeria and was significantly associated with several associated risk factors. Rapid screening for high-risk HPV genotypes is recommended and multivalent HPV vaccines should be considered for women.

Association of HPV35 with cervical carcinogenesis among women of African ancestry: Evidence of viral-host interaction with implications for disease intervention

HPV35 has been found in only ∼2% of invasive cervical cancers (ICC) worldwide but up to 10% in Sub-Saharan Africa, warranting further investigation and consideration of impact on preventive strategies. We studied HPV35 and ethnicity, in relation to the known steps in cervical carcinogenesis, using multiple large epidemiologic studies in the U.S. and internationally. Combining five U.S. studies, we measured HPV35 positivity and, in Northern California, observed HPV35 type-specific population prevalence and estimated 5-year risk of developing precancer when HPV35-positive. HPV35 genetic variation was examined for differences in carcinogenicity in 1053 HPV35+ cervical specimens from a U.S. cohort and an international collection. African-American women had more HPV35 (12.1% vs 5.1%, P < .001) and more HPV35-associated precancers (7.4% vs 2.1%, P < .001) compared to other ethnicities. Precancer risks after HPV35 infection did not vary by ethnicity (global P = .52). The HPV35 A2 sublineage showed an increased association with precancer/cancer in African-Americans (OR = 5.6 vs A1, 95% CI = 1.3-24.8) and A2 was more prevalent among ICC in Africa than other world regions (41.9% vs 10.4%, P < .01). Our analyses support a strong link between HPV35 and cervical carcinogenesis in women of African ancestry. Current HPV vaccines cover the majority of cervical precancer/cancer across all ethnic groups; additional analyses are required to determine whether the addition of HPV35 to the already highly effective nine-valent HPV vaccine would provide better protection for women in Africa or of African ancestry.

Design and feasibility of a novel program of cervical screening in Nigeria: self-sampled HPV testing paired with visual triage

Background

Accelerated global control of cervical cancer would require primary prevention with human papillomavirus (HPV) vaccination in addition to novel screening program strategies that are simple, inexpensive, and effective. We present the feasibility and outcome of a community-based HPV self-sampled screening program.

Methods

In Ile Ife, Nigeria, 9406 women aged 30-49 years collected vaginal self-samples, which were tested for HPV in the local study laboratory using Hybrid Capture-2 (HC2) (Qiagen). HPV-positive women were referred to the colposcopy clinic. Gynecologist colposcopic impression dictated immediate management; biopsies were taken when definite acetowhitening was present to produce a histopathologic reference standard of precancer (and to determine final clinical management). Retrospective linkage to the medical records identified 442 of 9406 women living with HIV (WLWH).

Results

With self-sampling, it was possible to screen more than 100 women per day per clinic. Following an audio-visual presentation and in-person instructions, overall acceptability of self-sampling was very high (81.2% women preferring self-sampling over clinician collection). HPV positivity was found in 17.3% of women. Intensive follow-up contributed to 85.9% attendance at the colposcopy clinic. Of those referred, 8.2% were initially treated with thermal ablation and 5.6% with large loop excision of transformation zone (LLETZ). Full visibility of the squamocolumnar junction, necessary for optimal visual triage and ablation, declined from 68.5% at age 30 to 35.4% at age 49. CIN2+ and CIN3+ (CIN- Cervical intraepithelial neoplasia), including five cancers, were identified by histology in 5.9 and 3.2% of the HPV-positive women, respectively (0.9 and 0.5% of the total screening population), leading to additional treatment as indicated. The prevalences of HPV infection and CIN2+ were substantially higher (40.5 and 2.5%, respectively) among WLWH. Colposcopic impression led to over- and under-treatment compared to the histopathology reference standard.

Conclusion

A cervical cancer screening program using self-sampled HPV testing, with colposcopic immediate management of women positive for HPV, proved feasible in Nigeria. Based on the collected specimens and images, we are now evaluating the use of a combination of partial HPV typing and automated visual evaluation (AVE) of cervical images to improve the accuracy of the screening program.

Prevalence and Type Distribution of Human Papillomavirus Recovered from the Uterine Cervix of Nigerian Women: A Systematic Review and Meta-Analysis

Background:

Infection with an oncogenic type of human papillomavirus is a prerequisite for the development of precancerous cervical lesions and its subsequent progression to cervical cancer. With an alarming increase in the detection of other suspicious papillomavirus genotypes in both healthy and women with cervical lesions, there is a need for comprehensive data on cervical papillomavirus infection to address cervical cancer and other associated disease burden, especially in Sub-Sarahan Africa, where the bulk of the problem exists. The present study was conducted to develop comprehensive data on the prevalence and circulating genotypes of human papillomavirus in various risk categories in Nigeria.

Methods:

A systematic review and meta-analysis of peer-reviewed publications on cervical papillomavirus infection were performed. Relevant data were extracted from eligible studies published in PubMed, Web of Science, Embase, Scopus, and Google Scholar, from inception to July 31, 2019. The random-effect model was used to estimate the pooled prevalence. We identified 327 potential studies and pooled data from 18, involving 5697 women aged 15-86 years.

Results:

The overall pooled prevalence of cervical papillomavirus infection was 42% (95%CI: 30-54%) in the general population and 37% (95%CI: 25-50%) among women living with HIV/AIDs, with the predominance of genotypes 16, 18, 31, 35, 52, 58 and 45. The highest prevalence was observed in teenagers and young adults and the second peak in women 50 years and above.

Conclusion:

The prevalence of cervical human papillomavirus infection is cumulatively high in Nigeria and HIV is a strong co-factor. We, therefore, strongly recommend the co-screening of human papillomavirus and cervical cancer and integration of the intervention strategy into the existing HIV-care guideline in Nigeria.

Recruiting population controls for case-control studies in sub-Saharan Africa: The Ghana Breast Health Study

Background

In case-control studies, population controls can help ensure generalizability; however, the selection of population controls can be challenging in environments that lack population registries. We developed a population enumeration and sampling strategy to facilitate use of population controls in a breast cancer case-control study conducted in Ghana.

Methods

Household enumeration was conducted in 110 census-defined geographic areas within Ghana’s Ashanti, Central, Eastern, and Greater Accra Regions. A pool of potential controls (women aged 18 to 74 years, never diagnosed with breast cancer) was selected from the enumeration using systematic random sampling and frequency-matched to the anticipated distributions of age and residence among cases. Multiple attempts were made to contact potential controls to assess eligibility and arrange for study participation. To increase participation, we implemented a refusal conversion protocol in which initial non-participants were re-approached after several months.

Results

2,528 women were sampled from the enumeration listing, 2,261 (89%) were successfully contacted, and 2,106 were enrolled (overall recruitment of 83%). 170 women were enrolled through refusal conversion. Compared with women enrolled after being first approached, refusal conversion enrollees were younger and less likely to complete the study interview in the study hospital (13% vs. 23%). The most common reasons for non-participation were lack of interest and lack of time.

Conclusions

Using household enumeration and repeated contacts, we were able to recruit population controls with a high participation rate. Our approach may provide a blue-print for others undertaking epidemiologic studies in populations that lack accessible population registries.

Human papilloma virus genotype distribution and risk factor analysis amongst reproductive-age women in urban Gambia

PURPOSE

Cervical cancer is the most frequently diagnosed female cancer in The Gambia, representing approximately 30 % of cases. In 2014, the quadrivalent human papilloma virus (HPV) vaccine was introduced, which offers protection against HPV genotypes 6, 11, 16 and 18. To evaluate the potential effectiveness of this vaccine, genotype distribution and risk factor analysis were assessed.

METHODOLOGY

Endocervical samples (n=232) were collected from women aged 20-49 years residing in urban Gambia. A questionnaire was administered to capture socio-demographic and cervical cancer risk factors. HPV detection and genotyping was performed by PCR amplification of the L1 major capsid gene and analysis of sequenced PCR products.Results/Key findings. The prevalence of HPV was 12 % (28/232), and the high-risk (HR) genotype HPV 52 (5/28) was the most prevalent genotype. HR-HPV sequences had high identity (≥90 %) to isolates which originated from America, Europe and Asia but not from Africa. Half (14/28) of participants were co-infected with Ureaplasma urealyticum/parvum, which increases the risk of progression to cervical cancer. Female genital mutilation and the use of hormone contraception for >5 years were identified as potential risk factors for HPV infection. Ethnicity-associated differences were also noted; participants of the Fula ethnic group had a higher prevalence of HR-HPV infection (31.3 %) compared to the Mandinka (18.8 %) and Wollof (12.5 %) groups.

CONCLUSION

These data may have a significant public health impact as the HPV quadrivalent vaccine may be of limited value if the circulating non-HPV 16/18 HR-genotypes are responsible for cytological abnormalities of the cervix.

Comparison between self sampling and provider collected samples for Human Papillomavirus (HPV) Deoxyribonucleic acid (DNA) testing in a Nigerian facility

Introduction

The multiple visits required for an effective Pap smear screening program is difficult to replicate in many developing countries. This precludes early diagnosis and care for patients with cervical cancer and contributes to its high mortality in these countries. HPV screening has higher specificity and high negative predictive value and has the advantage that materials can be self-collected, which permits the screening of women who for various cultural and religious reasons would be reluctant to come to the clinic to expose themselves for screening. The aim of the study was to assess the degree of agreement between self sampling for HPV DNA with samples collected by a health provider.

Methods

Each respondent selected from women presenting for cervical cancer screening underwent both self- and provider sampling for HPV DNA testing using Hybribio GenoArray.

Results

Of the 194 women screened, 12 (6.2%) and 19 (9.8%) had HPV on self sampling and provider col-lected samples respectively. The commonest HPV type seen using both techniques was HPV 58 (2.6%). Multiple HPV genotypes were seen in 1 (0.5%) and 5 cases (2.6%) of provider and self-collected samples respectively. The high risk-HPV detection rate was 7.2% when self sampled and 6.8% when sampled by the provider. There was moderate correlation between both sampling techniques (κ = 0.47, 95% CI: 21.3 - 72.3%, P < 0.05).

Conclusion

Our study shows moderate correlation between both sampling techniques. Larger multicentre studies will be needed to provide results generalisable to the Nigerian population. Keywords: Pap smear, HPV screening, cervical cancer, sample collection, self-sampling, provider collected, PCR, HPV DNA, Ile-Ife Nigeria.

Prevalence and risk factors for genital high-risk human papillomavirus infection among women attending the out-patient clinics of a university teaching hospital in Lagos, Nigeria

Introduction

Cervical cancer is the second most common cancer among women in the developing countries and the seventh commonest cancer in the developed countries. Human papillomavirus (HPV) is now known to be the main factor in the aetiology of cervical cancer with over 99.7% of cases being associated with previous high risk HPV (hrHPV) infection. This study was aimed to determine the prevalence and risk factors for genital hrHPV infection among women attending the out-patient clinics of the Lagos University Teaching Hospital.

Methods

This was a cross-sectional study involving a total of 200 women. Questionnaires were administered to collect data such as sociodemographic, reproductive and sexual histories. Endocervical swab samples were then taken from each participant. Samples were analyzed by polymerase chain reaction (PCR) using consensus primers targeted against the hrHPV viruses.

Results

The prevalence of hrHPV in the study was 36.5%. The most predominant HPV subtypes were 31 (25.0%), 35 (8.0%) and 16 (3.5%) with the largest proportion (76.1%) of the tested samples being positive for only a single hrHPV subtype. The study showed statistically significant associations between early age at coitarche (P = 0.032) and increasing number of lifetime sexual partners (P = 0.001) with genital hrHPV infection.

Conclusion

The prevalence of hrHPV was high in Lagos with the majority of test positive samples having only a single HPV genotype. We demonstrated early age of sexual debut and increasing number of lifetime sexual partners as the most important factors associated with genital hrHPV infection.

HPV test by Hybrid Capture II for the diagnosis of HR-HPV persistent infection

INTRODUCTION

Persistent high-risk HPV (HR-HPV) infection is associated with a greater risk of cervical cancer.

PATIENTS AND METHODS

Statistical data on the prevalence of HR-HPV infections in the Algerian population is lacking. We conducted a prospective study of 300 women aged between 25 and 50 years, screened for cervical cancer from 2012 to 2015 in Sidi Bel Abbès, a western region of Algeria. We aimed to assess the reliability of the repeated use of the HC II test (three longitudinal HPV tests 9 months apart from each other) in diagnosing the persistence of HR-HPV infection.

RESULTS

The prevalence of HR-HPV infection was 7.33% and infected women were aged 37.9±3years. For 90.9% of HR-HPV-positive patients, the infection persisted for a mean of 18.5months [95% CI: 16.9-22.1months]. Among these patients, 55.55% developed CIN1 and 11.11% developed CIN2. The sensitivity of the HC II test was 81.74% [95% CI: 71.3-89.6] and its positive predictive value associated with abnormal cervical biopsy was 27.49% [95% CI: 16.0-33.33].

CONCLUSION

Repeating the HC II test is a good predictor for identifying women at high risk of cervical cancer.

Persistent Low-Risk and High-Risk Human Papillomavirus Infections of the Uterine Cervix in HIV-Negative and HIV-Positive Women

BACKGROUND

The prevalence, persistence, and multiplicity of human papillomavirus (HPV) infection appears different comparing HIV-positive to HIV-negative women. In this study, we examined prevalent, persistent, and multiple low- and high-risk cervical HPV infections in HIV-negative and HIV-positive women.

METHODS

We studied 1,020 women involved in a study of HPV infection using SPF₂₅/LiPA₁₀. Two study visits were scheduled, at enrollment and 6 months afterward. At each study visit, research nurses used a cervical brush to collect samples of exfoliated cervical cells from the cervical os, from all the study participants. Exact logistic regression models were used to estimate associations between HIV and HPV infections.

RESULTS

The mean (SD) age of the study participants was 38 (8) years, 56% were HIV-negative and 44% were HIV-positive. Among HIV-negative women at baseline, single low-risk HPV (lrHPV) infections occurred in 12%; multiple lrHPV in 2%; single high-risk human papillomavirus (hrHPV) infections in 9%, and multiple hrHPV infections in 2%. Single lrHPV infections were persistent in 6%, but there was no persistent multiple lrHPV infections. Single hrHPV infections were persistent in 4% while multiple hrHPV infections were persistent in 0.3%. Among HIV-positive women at baseline, single lrHPV infections occurred in 19%, multiple lrHPV in 6%, single hrHPV infections in 17%, and multiple hrHPV infections occurred in 12%. Single lrHPV infections were persistent in 9%, multiple lrHPV infections in 0.6%, single hrHPV infections in 13%, while multiple hrHPV were persistent in 3%. Prevalent, persistent, and multiple infections were more common in HIV-positive women, compared to HIV-negative women. In multivariate models adjusted for age, marital status, socioeconomic status, age at sexual initiation, and douching, the odds ratios comparing HIV-positive to HIV-negative women, were 2.09 (95% CI 1.47-2.97, p < 0.001) for prevalent lrHPV, 1.26 (95% CI 0.66-2.40, p 0.47) for persistent lrHPV infections, 3.38 (95% CI 2.34-4.87, p < 0.001) for prevalent hrHPV, and 4.49 (95% CI 2.26-8.91, p < 0.001) for persistent hrHPV infections.

CONCLUSION

HIV infection was associated with higher prevalence of lrHPV, hrHPV, and persistence hrHPV infections, but not persistent lrHPV infections.

Differences in age-specific HPV prevalence between self-collected and health personnel collected specimen in a cross-sectional study in Ghana

BACKGROUND

HPV infections are ubiquitous and particularly common among sexually active young women. However, there are regional and national variations in age-specific HPV prevalence, which have implications for cervical cancer control. Data on age-specific HPV prevalences for Ghana and most sub-Saharan countries are scanty. Therefore, this study primarily sought to determine the age-specific HPV prevalence among women in a Ghanaian community and to determine whether these prevalences determined with health-personnel and self-collected specimens were comparable.

METHODS

In this cross-sectional study, conducted between March 2012 and March 2013, cervical specimens were collected by self- and health-personnel collection from 251 women who were between the ages of 15 and 65 years. HPV present in these specimens were genotyped by a nested-multiplex PCR and Luminex fluoro-microspheres based method. Information on the demographic, sexual and reproductive characteristics of the women were also obtained. A Chi-square test of association was employed to determine the association of the distribution of age groups with each categorised sexual and reproductive characteristic and HPV risk type's status.

RESULTS

The age group distribution of the participants was significantly associated with overall (χ2 = 36.1; p = 0.001), high risk (χ2 = 26.09; p = 0.002) and low risk (χ2 = 21.49; p = 0.011) HPV prevalences. The age-specific HPV prevalence pattern for each of the HPV risk types, determined with self-collected specimen, showed three peaks (at 20-24 years; 40-44 years and ≥ 55 years), while those determined with health-personnel collected specimen, showed two peaks (at 20-24 years and ≥ 55 years) for each HPV risk type's prevalence pattern. The high risk HPV prevalences determined with self-collected specimen were often higher than those determined with health-personnel specimen for the age groups between 25 and 45 years, who are mostly targeted for screening by HPV testing. Additionally, there were interesting variations in patterns of age-specific HPV genotype-specific prevalence between the two specimen collection methods.

CONCLUSIONS

The usefulness of self-collected specimen for high risk HPV burden determination and the existence of a two peaked and three peaked age-specific HPV prevalences in Ghana have been clearly indicated.

Randomized trial evaluating self-sampling for HPV DNA based tests for cervical cancer screening in Nigeria

Background

Cervical cancer incidence and mortality rates in Sub-Saharan Africa (SSA) remain high due to several factors including low levels of uptake of cervical cancer screening. Self-collection of cervicovaginal samples for HPV DNA testing may be an effective modality that can increase uptake of cervical cancer screening in SSA and hard to reach populations in developed countries. We investigated whether self-collection of cervicovaginal samples for HPV DNA tests would be associated with increased uptake of screening compared with clinic based collection of samples. Furthermore, we compared the quality of samples collected by both approaches for use in HPV genotyping.

Methods

We conducted a community based randomized trial in a semi-urban district of Abuja, Nigeria with 400 women, aged 30 to 65 years randomized to either hospital-collection or self-collection of cervicovaginal samples. We compared cervical cancer screening uptake among the 2 groups and evaluated the concentration of human DNA in the samples by measuring RNase P gene levels using qPCR. High-risk HPV DNA detection and typing was done using the GP5+/6+ Luminex system.

Results

Most participants in the self-collection arm (93%, 185/200) submitted their samples while only 56% (113/200) of those invited to the hospital for sample collection attended and were screened during the study period (p value < 0.001). Human genomic DNA was detected in all but five (1.7%) participants, all of whom were in the self-collection arm. The prevalence of high-risk HPV in the study population was 10% with types 35, 52 and 18 being the commonest.

Conclusions

Our study shows that self-sampling significantly increased uptake of HPV DNA based test for cervical cancer screening in this population and the samples collected were adequate for HPV detection and genotyping. Cervical cancer screening programs that incorporate self-sampling and HPV DNA tests are feasible and may significantly improve uptake of cervical cancer screening in SSA.

Prevalence of and Associated Risk Factors for High Risk Human Papillomavirus among Sexually Active Women, Swaziland

BACKGROUND

High risk human papillomavirus (hr-HPV) infection and the dual burden of HIV remains a huge challenge in some low-income countries (LICs) such as Swaziland with limited or no data. We estimated the prevalence and investigated determinants of hr-HPV, including HIV infection among sexually active women in Swaziland.

METHODS

A total of 655 women aged between 15 and 49 years from five health facilities were randomly enrolled using a cross-sectional study design. Cervical cells were tested for hr-HPV types using GeneXpert HPV Assays.

RESULTS

The overall weighted hr-HPV prevalence was 46.2% (95%CI: 42.8-49.5). Of hr-HPV infected women, 12.4% (95%CI: 8.6-17.5) were HPV16-positive, 13.8% (95%CI:12.0-15.8) were positive for HPV18/45, 26.7% (95%CI: 24.2-29.3) for HPV31/33/35/52/58, 7.6% (95%CI: 7.6-11.9) for HPV51/59 and 11.0%, (95%CI: 7.9-15.3) for HPV39/56/66/68. Prevalence of hr-HPV decreased with increasing age. Overall HIV prevalence remained high (42.7%; 95%CI: 35.7-46.2). HIV infection was associated with hr-HPV infection (Adjusted OR = 4.9, 95%CI: 3.043-7.8, p<0.001). Overall hr-HPV/HIV co-infection was 24.4% (95%CI: 20.3-29.1) which was significantly higher among younger age groups (p<0.001). Prevalence of multiple group hr-HPV infection was significantly higher in HIV-positive versus -negative women (27.7% and 12.7% respectively, p<0.001). The presence, absence or unknown of history of STI with HIV did not appear to modify the relationship with hr-HPV (OR = 4.2, 95%CI: 2.6-7.1, OR = 4.6, 95%CI: 2.8-7.7, p<0.001, p<0.001 and OR = 4.1, 95%CI: 1.3-13.4, p<0.021 respectively).

CONCLUSION

The prevalence of hr-HPV infection was high and significantly associated with HIV among sexually active women. Furthermore, the study has provided essential information about the HIV link with hr-HPV infections which may explain the high prevalence among HIV infected women. This can contribute to policy development and planning of prevention strategies incorporating HPV infection prevention especially among youth and HIV infected people.

Human papillomavirus infection in Rwanda at the moment of implementation of a national HPV vaccination programme

BACKGROUND

Cervical cancer is the most common female cancer in Rwanda that, in 2011, became the first African country to implement a national vaccination programme against human papillomavirus (HPV).

METHODS

To provide a robust baseline for future evaluations of vaccine effectiveness, cervical cell specimens were obtained from 2508 women aged 18-69 years from the general population in Kigali, Rwanda, during 2013/14. 20 % of women were HIV-positive. Samples were used for liquid-based cytology and HPV testing (44 types) with GP5+/6+ PCR.

RESULTS

HPV prevalence was 34 %, being highest (54 %) in women ≤19 years and decreasing to 20 % at age ≥50. Prevalence of high risk (HR) HPV and cytological abnormalities was 22 and 11 % respectively (including 2 % with high-grade squamous intraepithelial lesions, HSIL) decreasing with age. Age-standardised prevalence of HR HPV was 22 % (or 19 % among HIV-negative women), and HPV16 was the most common type. Prevalence of HPV and cytological abnormalities were significantly higher in HIV-positive than HIV-negative women, and the difference increased with age. Other significant risk factors for HPV positivity in multivariate analyses were high lifetime number of sexual partners, receiving cash for sex, and being a farmer. 40 % of women with HSIL were infected with HPV16/18 and there was no significant difference between HIV-positive and HIV-negative women.

CONCLUSIONS

This study confirms Rwanda to be a setting of high prevalence of HPV and cervical disease that is worsened by HIV. These data will serve as a robust baseline for future evaluations of HPV vaccine programme effectiveness.

Prevalence of IgG Antibodies against Human Papillomavirus (HPV) type 6, 11, 16, and 18 Virus-Like Particles in Women of Childbearing Age in Port Harcourt, Nigeria

Most HPV prevalence studies have been carried out in high-resource countries with few studies focused on low-resource regions where highest HPV prevalence in the world occurs. This study reports on prevalence of IgG antibodies against HPVs among women of childbearing age in Port Harcourt, Nigeria. One hundred and eighty-two consented women (age-range 19-45 years) were consecutively recruited. Demographic/behavioral data and 5 mL blood samples were collected from each woman. Plasma of each sample was assayed for HPV-6/11/16/18 virus-like particles using a HPV IgG ELISA kit. The overall anti-HPV prevalence was 4.9% while 7.7% with itching/wound in the private part tested positive. Most (88.9%) of the seropositive women were sexually active. Group-specific seropositivity was low (0.0-10.0%). It also showed that all the 9(100.0%) who tested positive to the HPV responded "yes" to no information on the source of HPV information. Being younger, married, high educational level, religion, and lack of information on HPV were the main correlates of HPV positivity among these women. None was vaccinated and would have been naturally exposed to at least one of HPV-6/11/16/18. With 4.9% seropositivity and lack of information regarding HPV among these women, this study recommends a statewide enlightenment campaign and vaccination.

Epidemiological patterns of cervical human papillomavirus infection among women presenting for cervical cancer screening in North-Eastern Nigeria

Background

Sub-Saharan countries including Nigeria have the highest burden of Human Papillomavirus (HPV) infection in the world. Most studies on HPV surveillance in Nigeria were done in the southern part of the country. Geographical and socio-cultural diversity of Nigeria makes these data unlikely to be universally representative for the entire country. Northern Nigeria especially the North-East carries a higher prevalence of cervical cancer and many of its risk factors. The region may be harbouring a higher prevalence of HPV infection with a possibility of different genotypic distribution. This study was carried out to determine the burden and confirm the predominant HPV genotypes among women presenting for cervical cancer screening at the Federal Teaching Hospital Gombe (FTHG), North-eastern, Nigeria.

Methods

The study was an observational hospital based cross sectional study among women who presented for cervical cancer screening in FTHG. A total of 209 consenting women were tested for cervical HPV infection using PCR. DNA sequencing was carried out on positive samples to determine the prevalent HPV genotypes.

Results

The prevalence of cervical HPV infection among the participants with mean age of 39.6 ± 10.4 years was 48.1 %. The five most predominant genotypes were 18, 16, 33, 31 and 35, with prevalence of 44.7 %, 13.2 %, 7.9 %, 5.3 % and 5.3 % respectively. Other genotypes observed were 38, 45, 56, 58, 82 and KC5. Multiple HPV infections were detected among 7.9 % of participants. Risk factors such as level of education (X² = 15.897; p = 0.007), age at sexual debut (X² = 6.916; p = 0.009), parity (X² = 23.767; p = 0.000), number of life time sexual partners (X² = 7.805; p = 0.005), age at first pregnancy (X² = 10.554; p = 0.005) and history of other malignancies (X² = 7.325; p = 0.007) were found to have a statistically significant association with HPV infection.

Conclusion

This study identified a high burden of HPV infection in Northern Nigeria while also confirming HPV 18 and 16 as the most predominant genotypes. It further justifies the potential benefit of the currently available HPV vaccines in the area. A larger and community based study is however recommended for better representation of the area.

Electronic supplementary material

The online version of this article (doi:10.1186/s13027-015-0035-8) contains supplementary material, which is available to authorized users.

Nationwide prevalence of human papillomavirus infection and viral genotype distribution in 37 cities in China

Background

Type-specific high-risk HPV (hrHPV) infection is related to cervical carcinogenesis. The prevalence of hrHPV infection varies geographically, which might reflect the epidemiological characteristics of cervical cancer among different populations. To establish a foundation for HPV-based screening and vaccination programs in China, we investigated the most recent HPV prevalence and genotypic distributions in different female age groups and geographical regions in China.

Methods

In 2012, a total of 120,772 liquid-based cytological samples from women enrolled for population- or employee-based cervical screening in 37 Chinese cities were obtained by the Laboratory of Molecular Infectious Diseases of Guangzhou KingMed. A total of 111,131 samples were tested by Hybrid Capture II and the other 9,641 were genotyped using the Tellgenplex™ HPV DNA Assay.

Results

The total positive rate for hrHPV was 21.07 %, which ranged from 18.42 % (Nanchang) to 31.94 % (Haikou) and varied by region. The regions of Nanchang, Changsha, Hangzhou, Chengdu, Fuzhou, Guangdong, and Guiyang could be considered the low prevalence regions. Age-specific prevalence showed a “two-peak” pattern, with the youngest age group (15–19 years) presenting the highest hrHPV infection rate (30.55 %), followed by a second peak for the 50–60-year-old group. Overall, the most prevalent genotypes were HPV16 (4.82 %) and HPV52 (4.52 %), followed by HPV58 (2.74 %). Two genotypes HPV6 (4.01 %) and HPV11 (2.29 %) were predominant in the low-risk HPV (lrHPV) type, while the mixed genotypes HPV16 + 52 and HPV52 + 58 were most common in women with multiple infections.

Conclusions

This study shows that HPV infection in China has increased to the level of an “HPV-heavy-burden” zone in certain regions, with prevalence varying significantly among different ages and regions. Data from this study represent the most current survey of the nationwide prevalence of HPV infection in China, and can serve as valuable reference to guide nationwide cervical cancer screening and HPV vaccination programs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-0998-5) contains supplementary material, which is available to authorized users.

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.

Cervical human papillomavirus prevalence and genotype distribution among hybrid capture 2 positive women 15 to 64 years of age in the Gurage zone, rural Ethiopia

Background

Human papillomavirus (HPV) infection is a prerequisite of cervical cancer, the leading cause of cancer mortality in Ethiopian women today. Data on Ethiopian cervical HPV prevalence and genotype distribution are rare, but essential as pre-vaccine baseline data to monitor changes after initiating HPV vaccination. The objectives of this study were to assess the cervical HPV prevalence, genotype distribution and associated correlates among female hospital outpatients in rural Ethiopia.

Methods

We examined a consecutive sample of 537 women 15–64 years of age in rural Ethiopia between November and December 2006. Screening for low risk (LR) and high-risk (HR) cervical HPV infection was performed and HR positive samples were genotyped with a GP5+/6 + − and SPF10-primer based system.

Results

The age-standardized prevalence of HPV, HPV HR and HPV LR infection was 17.3% (95% CI 14.1-20.5), 15.8% (95% CI 12.7-18.9) and 3.9% (95% CI 2.3-5.6), respectively. Among HC2 HPV HR positive infections (n = 86), the most common genotype was HPV 16 (24.4%), followed by 52 (11.6%), 56 (10.5%) and 31 (10.5%). Non-married relationship and widowhood, increasing number of lifetime sexual partners, human immunodeficiency virus infection and non-traditional housing type, but not age, were significantly associated with HR HPV infection.

Conclusions

These results on cervical HPV prevalence and genotype distribution may serve as baseline data in evaluating the impact of future HPV vaccination programmes in rural Ethiopia.

Electronic supplementary material

The online version of this article (doi:10.1186/1750-9378-9-33) contains supplementary material, which is available to authorized users.

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.

Age-specific prevalence of human papilloma virus infection among Nigerian women

BACKGROUND

Inconsistent trends in HPV prevalence by age have been described in Africa. We examined the age prevalence pattern and distribution of 37 HPV-DNA types among urban Nigerian women.

METHODS

The study population was a sample of 278 women who presented to cervical cancer screening programs in Abuja, Nigeria, between April and August 2012. Using a nurse administered questionnaire, information on demographic characteristics and risk factors of cervical cancer was collected and samples of cervical exfoliated cells were obtained from all participants. Roche Linear Array HPV Genotyping Test® was used to characterize prevalent HPV and log-binomial regression models were used to examine the association between potential correlates and the prevalence of HPV infection.

RESULTS

The mean age (SD) of the women enrolled was 38 (8) years. The overall prevalence of HPV was 37%. HPV 35 was the most prevalent HPV type in the study population. Among women age ≤ 30 years, 52% had HPV infection compared to 23% of those women who were older than 45 years (p = 0.006). We observed a significant linear association between age and the prevalence of HPV infections. The prevalence ratio (PR) and 95% confidence interval (CI) was 2.26 (1.17, 4.34) for any HPV infection, 3.83 (1.23, 11.94) for Group 1 HPV (definite carcinogens), and 2.19 (0.99, 4.84) for Group 2a or 2b HPV (probable or possible carcinogens) types, among women aged 18-30 years, compared to women who were older than 45 years.

CONCLUSION

The prevalence of HPV infection was highest among younger women and decreased steadily with age among this population of urban Nigerian women.

HPV self-sampling as primary screening test in sub-Saharan Africa: implication for a triaging strategy

Our objective was (i) to assess if a self-collected test for human papillomavirus (HPV) may serve as a primary cervical cancer screening method in a low-resource setting, (ii) to evaluate its implication in a screen and treat approach and (iii) to identify the most eligible age group in a screening program. Women were recruited through a cervical cancer screening campaign conducted in Cameroon. Written and oral instructions were given to participants by a health-care professional to carry out an unsupervised self-collected HPV-test (Self-HPV), followed by a physician-collected cervical sample for HPV testing (Physician-HPV) and cytology. Differences in performance between Self-HPV versus Physician-HPV and their ability to detect abnormal cytology results (ASC-US+) were evaluated. Descriptive analyses were used to examine the correlation between HPV positivity and cervical abnormalities by age. A sample of 789 women was prospectively enrolled. HPV prevalence was 14.6% and 12.7% for Self-HPV and Physician-HPV, respectively (Cohen's kappa = 0.74). HPV positivity by cytological diagnosis for ASC-US+ was similar with the two tests. positive predictive value of the Self-HPV for ASC-US+ was 20.4; odds ratio and number needed to treat were 6.5 (3.2-13.4) and 6 (4.2-10.9), respectively. We observed a trend of increasing cytological abnormalities in 30-49 year-old women and a concomitant trend of decreasing HPV prevalence supporting that this age group might be the most eligible group for screening. In conclusion, Self-HPV can be used as a primary screening test but needs to be followed by a triaging test that would identify the subset of women affected by clinically significant precancer or cancer.

The burden, distribution and risk factors for cervical oncogenic human papilloma virus infection in HIV positive Nigerian women

BACKGROUND

The expected reduction in cervical cancer incidence as a result of increased access to antiretroviral therapy is yet to be seen. In this study we investigated the effect of HIV infection and treatment on high-risk (hr) human papilloma virus (HPV) prevalence and distribution.

METHODS

Cervical cells from 515 (220 HIV positive and 295 HIV negative) women, recruited during community cervical cancer screening programme in states of Ogun and Lagos and at the cervical cancer screen clinic, Nigerian Institute of Medical Research Lagos were evaluated for the presence of 13 hr HPV genotypes by polymerase chain reaction based assay.

RESULTS

The prevalence of high-risk HPV was 19.6% in the studied population. HPV 16 (3.9%), 35 (3.5%), 58 (3.3%) and 31 (3.3%) were the most common hr HPV infections detected. We observed that the prevalence of hr HPV was higher in HIV positives (24.5%) than 15.9% in HIV negative women (OR = 1.7; 95% CI: 1.1-2.7). A multivariate logistic regression analysis showed a lower hr HPV prevalence in HIV positive women on antiretroviral drugs (OR = 0.4; 95% CI: 0.3-0.5) and with CD4 count of 500 and above (OR = 0.7; 95% CI: 0.5-0.8). A higher prevalence of hr HPV was also noted in HIV positive women with CD4 count < 200 cells/mm³ (OR = 2.4; 95% CI: 1.7-5.9).

CONCLUSION

HPV 16, 35, 58 and 31 genotypes were the most common hr HPV infection in our study group, which could be regarded as high risk general population sample; with higher prevalence of HPV 16 and 35 in HIV positive women than in HIV negative women. The use of antiretroviral drugs was found to be associated with a lower prevalence of hr HPV infection, compared to those not on treatment. This study raises important issues that should be further investigated to enable the development of robust cervical cancer prevention and control strategies for women in our setting.

HIV associated high-risk HPV infection among Nigerian women

BACKGROUND

In developed countries, the incidence of cervical cancer has remained stable in HIV+ women but the prevalence and multiplicity of high-risk HPV (hrHPV) infection, a necessary cause of cervical cancer, appears different comparing HIV+ to HIV- women. Little is known about HIV and HPV co-infection in Africa.

METHODS

We enrolled women presenting at our cervical cancer screening program in Abuja, Nigeria between April and August 2012, and collected information on demographic characteristics, risk factors of HPV infection and samples of exfoliated cervical cells. We used Roche Linear Array HPV Genotyping Test® to characterize prevalent HPV and logistic regression models to estimate the association between HIV and the risk of hrHPV infection.

RESULTS

There were 278 participants, 54% (151) were HIV+, 40% (111) were HIV-, and 6% (16) had unknown HIV status. Of these, data from 149 HIV+ and 108 HIV- women were available for analysis. The mean ages (± SD) were 37.6 (± 7.7) years for HIV+ and 36.6 (± 7.9) years for HIV- women (p-value = 0.34). Among the HIV+ women, HPV35 (8.7%) and HPV56 (7.4%) were the most prevalent hrHPV, while HPV52 and HPV68 (2.8%, each) were the most prevalent hrHPV types among HIV- women. The multivariate prevalence ratio for any hrHPV and multiple hrHPV infections were 4.18 (95% CI 2.05 - 8.49, p-value <0.0001) and 6.6 (95% CI 1.49 - 29.64, p-value 0.01) respectively, comparing HIV + to HIV- women, adjusted for age, and educational level.

CONCLUSIONS

HIV infection was associated with increased risk of any HPV, hrHPV and multiple HPV infections. Oncogenic HPV types 35, 52, 56 and 68 may be more important risk factors for cervical pre-cancer and cancer among women in Africa. Polyvalent hrHPV vaccines meant for African populations should protect against other hrHPV types, in addition to 16 and 18.

Plasma cytokine levels and human papillomavirus infection at the cervix in rural Nigerian women

INTRODUCTION

We conducted a study to test the hypothesis that systemic dysregulation of Th1/Th2 cytokine levels was associated with detection of carcinogenic or overall human papillomavirus (HPV) at the cervix among 964 women residing in a rural village in Nigeria.

METHODS

Levels in plasma were measured for 19 cytokines, including Th1-like cytokines IL-2, IL-12 (p40), TNF-a, IFN-g; Th2-like cytokines IL-4, IL-5, IL-6, IL-10, IL-13; innate/inflammation cytokines IL-1a, IL-1b, IL-8, eotaxin, MCP-1, MIP-1a, and IL-7; and cell development cytokines G-CSF, VEGF, and IL-17. Analysis was restricted to 5 cytokines, TNF-α (Th1), IL-8 (Th2), eotaxin and MCP-1 (innate/inflammation), and G-CSF (cell development), whose levels were detected in 80% or more of the samples measured as well as had a coefficient of variation of <30%.

RESULTS

Strong correlations were noted between levels of eotaxin and TNF-α (r=0.75), IL-8 and MCP-1 (r=0.60), eotaxin and G-CSF (r=0.44), and G-CSF and IFN-γ (r=0.43). Detection of carcinogenic or non-carcinogenic HPV DNA was unrelated to cytokine levels, except for levels of eotaxin and TNF-α, which were inversely correlated, albeit weakly, with detection of any carcinogenic HPV (P=0.048 and P=0.067, respectively). In analyses stratified by age group, levels of eotaxin were inversely correlated with detection of any HPV DNA (P=0.026) and carcinogenic HPV (P=0.042) in older, but not younger, women.

CONCLUSIONS

Our results do not support the hypothesis of association between systemic cytokine dysregulation and detection of HPV at the cervix in Nigerian women, but subgroup analyses raise questions about inverse associations between eotaxin and TNF-α in older women.

Difference in overall and age-specific prevalence of high-risk human papillomavirus infection in Italy: evidence from NTCC trial

BACKGROUND

Although among women a decreasing prevalence of human papillomavirus (HPV) infection with increasing age has been consistently observed in high-resource countries, different age profiles have been reported elsewhere.

METHODS

We compared the age profile of high-risk (HR)-HPV prevalence in nine different areas of Northern and Central Italy by studying the women recruited in the intervention arm of the New Technologies in Cervical Cancer study and tested by Hybrid Capture 2. Differences in the age-distribution of HPV infection were investigated in each centre by the joinpoint approach in a logistic model. 46,900 women aged 25 to 60 years were included in the analysis.

RESULTS

The HR-HPV age-standardised (on Italian population) prevalence ranged from 5.7% (Trento) to 10.3% (Ravenna). HR-HPV prevalence decreased as a logistic function of increasing age in 6 of 9 centres (Trento, Verona, Florence, Bologna, Imola, and Viterbo). The effect of age on HR-HPV prevalence slopes did not differ significantly among these 6 centres, whereas significant heterogeneity in intercepts (p < 0.001) was found, reflecting different overall HR-HPV prevalence between centres. One significant joinpoint was observed in 2 centres (Padua and Ravenna), indicating that the decrease in HR-HPV prevalence by age was better described using a function composed with two logistic segments. In Padua HR-HPV prevalence decreased only slightly up to 39 years but showed a steep downturn thereafter. In Ravenna HR-HPV prevalence decreased steeply down to 45 years of age and then showed a plateau. Finally, in Turin two significant joinpoints were observed: prevalence decreased only after age 29 and showed a plateau after age 39.

CONCLUSIONS

Our results showed substantial differences in overall and age-specific HR-HPV prevalence across Italian areas. These findings may be related to different timing of changes in sexual behaviours across regions. Age-specific HR-HPV prevalence in Italy does not support an influence of age per se.

HPV-based Tests for Cervical Cancer Screening and Management of Cervical Disease

Current cervical cancer screening programs are changing due to the development of tests that detect the presence of human papillomavirus (HPV), the cause of cervical cancer. These tests are more sensitive than cytology-based methods for detecting cervical precancer and a negative test offers long-term assurance that cervical cancer will not develop and therefore longer screening intervals can be achieved. In screening programs, HPV-based tests have been approved to triage women with equivocal cytology results and as a primary testing method in conjunction with cytology. HPV-based tests also have a role in determining risk of recurrence after treatment for cervical precancer as well as in surveillance for vaccine-related changes in HPV genotype prevalence.

A population-based study of visual inspection with acetic acid (VIA) for cervical screening in rural Nigeria

OBJECTIVE

Cervical cancer is the most common gynecological cancer in developing countries. Visual inspection with acetic acid (VIA) was introduced to screen for cervical premalignant lesions in developing countries owing to the inability of many countries to implement high-quality cytologic services. We sought to compare VIA performance among different health workers in Nigeria.

METHODS

In a population-based project, 7 health workers who had been screening women with VIA for approximately 2 years at local government health centers in rural Nigeria were retrained in a 2-week program using the International Agency for Research on Cancer training manual. Women from a rural village who had never had cervical cancer screening were recruited into the study. Each woman had cervical cancer screening by VIA, liquid-based cytologic test, and oncogenic human papillomavirus (HPV) DNA test.

RESULTS

Despite similar participant characteristics, across all age groups, providers had wide ranges of VIA results; 0% to 21% suspect cancer and 0% to 25% were VIA positive. Visual inspection with acetic acid was insensitive compared to a combination of cytologic and HPV tests.

CONCLUSION

In our study, VIA was not reproducible, nor was it sensitive compared to cytologic and HPV tests.

Prevalence and determinants of human papillomavirus infection and cervical lesions in HIV-positive women in Kenya

Background:

We assessed the association of human papillomavirus (HPV) infection and cervical intraepithelial neoplasia (CIN) with various characteristics, CD4 count and use of combination antiretroviral therapy (cART) among HIV-positive women.

Methods:

Cross-sectional study of 498 HIV-positive women who underwent HPV PCR-based testing, cytology, and systematic cervical biopsy.

Results:

In all, 68.7% of women were HPV-positive, 52.6% had high-risk (hr) HPV, and 40.2% multiple type infections. High-risk human papillomavirus-positivity did not vary significantly by age but it was negatively associated with education level. The most frequent types in 113 CIN2/3 were HPV16 (26.5%), HPV35 (19.5%), and HPV58 (12.4%). CD4 count was negatively associated with prevalence of hrHPV (P<0.001) and CIN2/3 among non-users of cART (P=0.013). Combination antiretroviral therapies users (⩾2 year) had lower hrHPV prevalence (prevalence ratio (PR) vs non-users=0.77, 95% confidence interval (CI): 0.61–0.96) and multiple infections (PR=0.68, 95% CI: 0.53–0.88), but not fewer CIN2/3. The positive predictive value of hrHPV-positivity for CIN2/3 increased from 28.9% at age <35 years to 53.3% in ⩾45 years.

Conclusion:

The burden of hrHPV and CIN2/3 was high and it was related to immunosuppression level. Combination antiretroviral therapies ( ⩾2 year) use had a favourable effect on hrHPV prevalence but cART in our population may have been started too late to prevent CIN2/3.

Cervical human papillomavirus and HIV infection in women of child-bearing age in Abidjan, Côte d'Ivoire, 2010

Background:

We sought to document the association of Human immunodeficiency Virus (HIV) infection and immunodeficiency with oncogenic Human Papillomavirus (HPV) infection in women with no cervical neoplastic lesions identified through a cervical cancer screening programme in Côte d’Ivoire.

Methods:

A consecutive sample of women stratified on their HIV status and attending the national blood donor clinic or the closest HIV clinic was recruited during a cervical cancer screening programme based on the visual inspection. Diagnosis of HPV infection and genotype identification were based on the Linear Array; HPV test.

Results:

A total of 445 (254 HIV-positive and 191 HIV-negative) women were included. The prevalence of oncogenic HPV infection was 53.9% (95% confidence interval (CI) 47.9–59.9) in HIV-positive women and 33.7% (95% CI 27.1–40.3) in HIV-negative women (odds ratio (OR)=2.3 (95% CI 1.5–3.3)). In multivariate analysis, HIV-positive women with a CD4 count <200 cells mm³ or between 200 and 499 cells mm³ were more likely to harbour an oncogenic HPV compared with women with a CD4 count ⩾500 cells mm³ with OR of 2.8 (95% CI 1.1–8.1) and 1.7 (95% CI 1.0–2.9), respectively.

Conclusion:

A high prevalence of oncogenic HPV was found in women with no cervical neoplastic lesions, especially in HIV-positive women. Despite antiretroviral use, immunodeficiency was a main determinant of the presence of oncogenic HPV.

Effectiveness of a simple rapid human papillomavirus DNA test in rural Nigeria

Success of the new human papillomavirus (HPV) DNA test for low-resource settings (careHPV™ test; QIAGEN Gaithersburg Inc., Gaithersburg, MD) requires good test performance when operated by personnel with limited laboratory experience. We evaluated the transferability, reliability, and accuracy of the careHPV test nested within a cervical screening project in a large Nigerian village. CareHPV testing was performed on screen-positive (n = 345) and screen-negative (n = 42) women attending colposcopy (68.3% of referred). Biopsies of abnormal-appearing areas were processed and read in the U.S. CareHPV specimens taken immediately before colposcopy were processed up to four times (in the field) by two secondary school graduates without laboratory experience, trained for this study. Specifically, QIAGEN Gaithersburg trained a laboratory-inexperienced U.S. researcher, who trained the first local technician who, in turn, trained the second. Residual specimens were sent to the U.S. for MY09/MY11 PCR testing for 13 carcinogenic genotypes (HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68) plus HPV66 (included in careHPV). Intrarater agreement was 98.8% (κ = 0.97) and 98.9% (κ = 0.97) for Technicians 1 and 2, respectively, while inter-rater agreement was 96.3% (κ = 0.90). Agreement with MY09/MY11 PCR (virologic reference standard) was 89.3% (κ = 0.73) with 74.2% sensitivity and 95.7% specificity. The careHPV test detected 12 (80%) of 15 histologically confirmed cervical intraepithelial neoplasia Grade 2 (CIN2) or worse lesions, with an estimated 83.0% specificity to detect <CIN2. In a challenging low-resource setting with minimal intervention, the careHPV test performed adequately with high specificity but possibly lower sensitivity than HPV DNA tests currently used in controlled situations.

Prevalence of human papillomavirus and cervical intraepithelial neoplasia in China: a pooled analysis of 17 population-based studies

High-risk (HR) human papillomavirus (HPV) prevalence has been shown to correlate well with cervical cancer incidence rates. Our study aimed to estimate the prevalence of HR-HPV and cervical intraepithelial neoplasia (CIN) in China and indirectly informs on the cervical cancer burden in the country. A total of 30,207 women from 17 population-based studies throughout China were included. All women received HPV DNA testing (HC2, Qiagen, Gaithersburg, MD), visual inspection with acetic acid and liquid-based cytology. Women positive for any test received colposcopy-directed or four-quadrant biopsies. A total of 29,579 women had HR-HPV testing results, of whom 28,761 had biopsy confirmed (9,019, 31.4%) or assumed (19,742, 68.6%) final diagnosis. Overall crude HR-HPV prevalence was 17.7%. HR-HPV prevalence was similar in rural and urban areas but showed dips in different age groups: at age 25-29 (11.3%) in rural and at age 35-39 (11.3%) in urban women. In rural and urban women, age-standardized CIN2 prevalence was 1.5% [95% confidence interval (CI): 1.4-1.6%] and 0.7% (95% CI: 0.7-0.8%) and CIN3+ prevalence was 1.2% (95% CI: 1.2-1.3%) and 0.6% (95% CI: 0.5-0.7%), respectively. Prevalence of CIN3+ as a percentage of either all women or HR-HPV-positive women steadily increased with age, peaking in 45- to 49-year-old women. High prevalence of HR-HPV and CIN3+ was detected in both rural and urban China. The steady rise of CIN3+ up to the age group of 45-49 is attributable to lack of lesion removal through screening. Our findings document the inadequacy of current screening in China while indirectly raising the possibility that the cervical cancer burden in China is underreported.

Burden of cancer in Malawi; common types, incidence and trends: national population-based cancer registry

Background

Cancer is a leading cause of morbidity and mortality worldwide with a majority of cases and deaths occurring in developing countries. While cancer of the lung, breast, colorectum, stomach and prostate are the most common types of cancer globally, in east and southern Africa these are less common and comprehensive data to inform policies are lacking.

Methods

Nationwide cancer registry was conducted between September and October 2010 in Malawi. New cancer cases registered from 2007 to 2010 were identified from hospital and clinic registers of 81 out of 84 health facilities providing cancer diagnosis, treatment or palliative care services. Demographic and cancer data were extracted from registers and case notes using a standard form.

Results

A total of 18,946 new cases of cancer were registered in Malawi from 2007-2010. Of these 55.9% were females, 7.2% were children aged less than 15 years, 76.5% were adults aged 15-59 years and 16.4% were elderly aged 60 years or more. Only 17.9% of the cases had histologically verified diagnosis, 33.2% were diagnosed clinically and 49.6% based on clinical and some investigations. Amongst females, cancer of the cervix was the commonest accounting for 45.4% of all cases followed by Kaposi sarcoma (21.1%), cancer of the oesophagus (8.2%), breast (4.6%) and non-Hodgkin lymphoma (4.1%). In males, Kaposi sarcoma was the most frequent (50.7%) then cancer of oesophagus (16.9%), non-Hodgkin lymphoma (7.8), prostate (4.0%) and urinary bladder (3.7%). Age-standardised incidence rate per 100,000 population for all types of cancer in males increased from 31 in 1999-2002 to 56 in 2007-2010. In females it increased from 29 to 69. Kaposi sarcoma and cancer of the oesophagus, cervical cancer and Kaposi sarcoma were the main causes for the increased incidence in males and females respectively. It was estimated that, annually at least 8,151 new cases of cancer (all types) occur in Malawi.

Conclusions

This study provided data on common types and trends of cancer that could be used to focus prevention, treatment and control interventions in the context of limited resources. The problem of under-reporting and misdiagnosis of cancer cases has been highlighted.

A population-based cross-sectional study of age-specific risk factors for high risk human papillomavirus prevalence in rural Nigeria

Background

Cervical cancer, caused by persistent infection with carcinogenic human papillomavirus (HR-HPV), is particularly prevalent in Sub-Saharan Africa and is associated with a high mortality rate. Some studies in West Africa, including our own, have found unusually high HR-HPV across all ages with a slight peak in older women. This increased prevalence at older ages may complicate screen-and-treat programs, which are implemented in regions where HPV prevalence declines with age and typically target women between 30-49 years. A better understanding of the determinants of high HR-HPV prevalence at older ages is needed. The goal of this study is to explore risk factors for HR-HPV prevalence by age among women in our population-based study in Irun, a rural town in southwestern Nigeria.

Methods

1,420 women were administered a clinic-based questionnaire regarding sexual and reproductive behavior, marital status (including co-wives), and malaria exposure. Logistic regression compared questionnaire responses and PCR positivity for a set of 13 carcinogenic HR-HPV types. Results were stratified by age (15-29, 30-45, 46-55, and 56+ years).

Results

Birth control use and age at first pregnancy were associated with HR-HPV (p-value = 0.03 and 0.05, respectively). Early age at sexual debut and multiple sex partners were risks for HR-HPV, but did not reach significance (p-value = 0.1 and 0.07, respectively). Neither self-reported malaria nor presence of co-wives in the household was associated with HR-HPV (p-value = 0.85 and 0.24, respectively). In age sub-categories, early age at sexual debut was a significant risk factor for HR-HPV among women 35-45 years (p-value = 0.02). Early age at first pregnancy remained a significant risk factor for women aged 56+ years (p-value = 0.04). Greater than 2 sex partners and use of birth control were associated (though not significantly) with HR-HPV in women aged 30-45 (p-value = 0.08, respectively).

Conclusions

In this high-risk region with elevated HR-HPV prevalence at older ages, we confirmed previously described, behavioral determinants of HR-HPV. There was no association with self-reported malaria or co-wives, which we had hypothesized might correlate with HR-HPV at older ages.