Human papillomavirus genotype prevalence in high-grade squamous intraepithelial lesions and colposcopically normal women from Zimbabwe

Human papillomavirus spectrum of HPV-infected women in Nigeria: an analysis by next-generation sequencing and type-specific PCR

BACKGROUND

Human papillomavirus (HPV) infection and cervical cancer are leading health problems and causes of death in many parts of the world. There are ~ 200 HPV types that can infect humans. This study aims to understand the spectrum of HPV infections in Nigerian women with normal or abnormal cytology.

METHODS

We screened cervical samples from 90 women with possible HPV infections collected in two regional hospitals in Nigeria. The first screening was done using next-generation DNA sequencing (NGS), identifying multiple HPV types in many samples. Thereafter, type-specific PCR analysis was used to verify the NGS-identified HPV types in each sample.

RESULTS

NGS analysis of the 90 samples from the Nigerian cohort identified 44 HPV types. The type-specific PCR confirmed 25 HPV types out of the 44 HPV types detected by NGS, and ~ 10 of these types were the most prevalent. The top five prevalent types found in the Nigerian cohort were HPV71 (17%), HPV82 (15%), HPV16 (16%), HPV6 (10%), and HPV20 (7%). Among the PCR-confirmed HPV types, we found 40.98% high-risk HPV types, 27.22% low-risk HPV types, and 31.15% undetermined HPV types. Among these 25 HPV types in Nigeria, only six were included in the current nine-valent HPV vaccine. We also observed strikingly high multiple HPV infections in most patients, with as many as nine HPV types in a few single samples.

CONCLUSIONS

Our NGS-PCR approach of HPV typing in the Nigerian cohort samples unveiled all possible HPV types currently circulating in Nigerian people. We confirmed 25 HPV types using NGS and PCR, with many samples infected with multiple HPV types. However, only six of these types are part of the nine-valent HPV vaccines indicating the need to develop region-specific selective vaccines.

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 Genotype Distribution of High-Risk Human Papillomavirus Infection Among Sub-Saharan African Women: A Systematic Review and Meta-Analysis

Background

Among sub-Saharan African women, cervical cancer is steadily increasing with more than 75,000 new cases and 50,000 deaths annually. Due to the vast ethno geography variation, Africa harbors heterogeneous genotypes of HPV. High-risk HPV [hr HPV] genotypes such as hr HPV-16,−18,-35, and−52 are abundantly reported in sub-Saharan Africa. The purpose of this systematic review and meta-analysis is to generate an evidence on the prevalence and the genotype distribution of hr HPV among sub-Saharan African countries.

Methods

The review was conducted by following the preferred reporting items for systematic reviews and Meta-analysis. PubMed/Medline, Embase, Scopus, Google Scholar, Heath Technology assessment and Cochrane Library databases were used to retrieve published original studies between 2001 and 2021. It included studies that used PCR-based or hybrid testing to assess the presence of HPV DNA in a cervical biopsy, cervical swelling, and vaginal swelling. Statistical software for data science (STATA V16) software using a random-effects model was used to determine the pooled prevalence and type-specific distribution of HPV with 95% confidence intervals (CI). The I-squared statistic was used to describe the level of heterogeneity. The study protocol is registered on PROSPERO with reference number CRD42022311157.

Results

The review included 27 studies conducted in 19 sub-Saharan countries. A total of 16,506 study participants from 27 studies were included in a systematic review and 5,303 of them were infected with the hr HPV infection. Out these, only 3,075 of them were eligible for meta-analysis. The incidence proportion of estimatesof hr HPV infection among study participants with different health conditions ranges from 10.7 to 97.2% while the pooled incidence proportion of estimates is 34% (95%CI: 29–39). Among 3,075 women, 424 (13.8%), 305 (9.9%) and 279 (9%) were infected with HPV-16,−52 and−18, respectively. HPV-16 and−52 are the main genotypes causing the hr HPV infection in the Eastern and Southern African sub-contents, whereas HPV-16 and−35 are the main genotypes in the Western African countries.

Conclusions

Depending on several factors, especially women's health conditions, the high rate of hr HPV infection with inconsistent genotype distribution shows that it is a growing public health challenge in sub-Saharan African countries. Therefore, to implement a vaccination-based prevention strategy and be effective, considering factors associated with hr HPV infection is crucial.

Prevalence and Distribution of Vaccine-Preventable Genital Human Papillomavirus(HPV) Genotypes in Ghanaian Women Presenting for Screening

BACKGROUND

Cervical cancer is the most common gynaecologic cancer in Ghana where it is also the second most common cause of all female cancers. A number of vaccines are available to provide both individual and population-level protection against persistent infection with high-risk human papillomaviruses (HR-HPV) and reduce the burden of cervical cancer. Data on the epidemiology of vaccine-preventable papillomaviruses in Ghana is scant.

METHODS

A cross-sectional observational study was implemented from May 2011 to November 2014 to understand the epidemiology of genital human papillomavirus (HPV) genotypes and cervical dysplasia in the Greater Kumasi area of Ghana. A nested multiplex polymerase chain reaction (NMPCR) assay incorporating degenerate E6/E7 consensus primers and type-specific primers was used for the detection and typing of eighteen (18) HPV genotypes among women who had never attended cervical screening prior to this study.

RESULTS

The general prevalence of HPV infection in Kumasi was 37.2%. The age-standardized prevalence was 40.9% overall. The frequency of HR-HPV genotypes present in decreasing order were HPV-52, -56, -35, -18, -58, -68, -51, -39, -45, -16, -59, -33 and -31. Low-risk HPVs were also detected in the following order: HPV-42, -43, -66, -6/11 and -44.

CONCLUSIONS

The study shows that currently available prophylactic vaccines have the potential to be useful in the primary prevention of HPV infections in the country. This study strengthens the belief that prophylactic HPV vaccination could be a long-term strategy to reduce the burden of HPV infections and potentially reduce the burden of HPV-associated cancers and epithelial cell abnormalities among health-seeking women in Kumasi. Efforts to make vaccines available to young girls should be prioritized.

Prevalence of vaccine and non-vaccine human papillomavirus types among women in Accra and Kumasi, Ghana: a cross-sectional study

BACKGROUND

Human Papillomavirus (HPV) infection is the main etiological factor for pre-invasive and invasive cervical cancer. HPV type-specific vaccination is being widely recommended to control the burden of disease, but the genotype-specific distribution of HPV may vary in different countries. The aim of the study was to determine the prevalence and distribution of HPV genotypes among women attending reproductive health services in Ghana, their associated risk factors, and to assess the potential coverage of identified HPV genotypes by three licensed vaccines among these women.

METHOD

Women presenting for reproductive health services in two regional hospitals in Accra and Kumasi from October 2014 to March 2015 were conveniently recruited into the study (n = 317). HPV-DNA detection and genotype identification were carried out by a nested multiplex PCR assay that combines degenerate E6/E7 consensus primers and type-specific primers for the detection and typing of eighteen HPV genotypes. Cytology was performed to screen women for cervical cancer lesions. Risk factors for HPV infection were analyzed by logistic regression. Statistical significance was accepted for p < 0.05.

RESULTS

The age of study participants ranged from 21 to 76 years. Among women positive for HPV, 35.0% were infected with high-risk HPV, 14.5% with probable high-risk HPV, and 17.0% with low-risk HPV. The prevalence of HPV 16/18 was 8.2%, HPV 6/11/16/18 was 9.1% and HPV 6/11/16/18/31/33/45/52/58 was 28.4%. The most prevalent among HR-HPV were types 52 (18.3%) and 58 (8.8%). HPV positivity may be associated with educational background (p < 0.001), age at first pregnancy (p = 0.028), and age at coitarche (p = 0.016).

CONCLUSIONS

Our study revealed a high prevalence of HR-HPV infection among women. The high prevalence of HR HPV indicates that multivalent vaccines will be useful for controlling HPV burden in general population contexts. The distribution of HPVs in this population suggests that of the three currently available vaccines the nonavalent vaccine, which protects against seven HPV types in addition to HPV 16 and 18, has the highest coverage of HPV infections among Ghanaian women. Healthcare officials planning to reduce the transmission of HPV and cervical cancer must consider the coverage of the nonavalent vaccine as an advantage.

Spectrum of high risk human papillomavirus types in women in Kaduna State, Nigeria

Context:

Infection with oncogenic or high-risk human papillomavirus (hrHPV) types acts as carcinogens in the development of cervical cancer.

Aim:

The aim of the study was to detect the genotypes of some hrHPVs among women attending selected hospitals in Kaduna State, Nigeria.

Settings and Design:

Hospital-based and cross-sectional that involved the use of structured questionnaires to obtain sociodemographic and clinical data.

Materials and Methods:

Two hundred and seventy-six cervical scraping samples were screened for both HPV and squamous intraepithelial lesion (SIL) using enzyme-linked immunosorbent assay and conventional Pap smear, respectively. Samples positive for HPV antigen and SIL were subjected to polymerase chain reaction (PCR) to detect the viral type.

Statistical Analysis Used:

Data were analyzed using the frequency procedure of Statistical Analysis System version 9.2, at 0.05 level of significance and 95% confidence interval.

Results:

Of the 276 cervical scraping samples, only 24 (8.7%) were positive for HPV antigen, whereas 17 (6.2%) were positive for SIL. When thirty of these positive samples were subjected to PCR, the DNA of hrHPV was detected in 20 (66.6%) of the positive samples. The HPV types detected in the study were 16 (36.7%), 18 (40.0%), 31 (16.7%), and 45 (3.3%).

Conclusion:

The findings from this study have shown that there is a high possibility of detecting the DNA of hrHPV in women that are infected with HPV and those that have cervical dysplasia, which points out the possibility of these women developing cervical cancer.

Molecular characterisation of genital human papillomavirus among women in Southwestern, Nigeria

Background

Persistent infections with high-risk genital Human papillomavirus (HPV) especially types 16 and 18, are associated with cervical cancer. However, distribution of HPV types varies greatly across geographical regions and the available vaccines target only few types. This study was designed to determine the HPV types circulating in Southwestern Nigeria, thereby providing necessary information for effective control of the virus.

Methods

Endocervical swab samples were collected from a total of 295 consenting women attending routine cervical cancer screening, STI clinics and community-based outreach programme. Viral DNA was extracted from the samples and the consensus region of the HPV DNA was amplified by PCR using GP-E6/E7 primers. Type-specific nested multiplex PCR and Sanger sequencing were used to genotype the HPV isolates.

Results

In this study, 51 (17.3%) individuals were positive for HPV DNA using consensus primers that target the E6/E7 genes but only 48 (16.3%) were genotyped. A total of 15 HPV types (HPV-6, 16, 18, 31, 33, 35, 42, 43, 44, 52, 58, 66, 74, 81, 86) were detected, with HPV-31 being the most predominant (32.8%), followed by HPV-35 (17.2%) and HPV-16 (15.5%). Two rare HPV types; 74 and 86 were also detected. The HPV-74 isolate had three nucleotide (CCT) insertions at E7 gene that translated into amino acid proline. Highest nucleotide substitutions (n = 32) were found in HPV-44 genotype. Among positive individuals, 20.8% had dual infections and 86.2% had High-risk HPV types.

Conclusions

Multiple Human papillomavirus types co-circulated in the study. Most of the circulating Human papillomavirus are high-risk type with type 31 being the most predominant. Although the implication of HPV-74 with proline insertion detected for the first time is unknown, it may have effect on the transformation potential of the virus. Polyvalent HPV vaccine will be more effective for the infection control in Nigeria.

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.

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.

PEG1/MEST and IGF2 DNA methylation in CIN and in cervical cancer

INTRODUCTION

Although most invasive cervical cancer (ICC) harbor <20 human papillomavirus (HPV) genotypes, use of HPV screening to predict ICC from HPV has low specificity, resulting in multiple and costly follow-up visits and overtreatment. We examined DNA methylation at regulatory regions of imprinted genes in relation to ICC and its precursor lesions to determine if methylation profiles are associated with progression of HPV-positive lesions to ICC.

MATERIALS AND METHODS

We enrolled 148 controls, 38 CIN and 48 ICC cases at Kilimanjaro Christian Medical Centre from 2008 to 2009. HPV was genotyped by linear array and HIV-1 serostatus was tested by two rapid HIV tests. DNA methylation was measured by bisulfite pyrosequencing at regions regulating eight imprinted domains. Logistic regression models were used to estimate odd ratios.

RESULTS

After adjusting for age, HPV infection, parity, hormonal contraceptive use, and HIV-1 serostatus, a 10 % decrease in methylation levels at an intragenic region of IGF2 was associated with higher risk of ICC (OR 2.00, 95 % CI 1.14-3.44) and cervical intraepithelial neoplasia (CIN) (OR 1.51, 95 % CI 1.00-2.50). Methylation levels at the H19 DMR and PEG1/MEST were also associated with ICC risk (OR 1.51, 95 % CI 0.90-2.53, and OR 1.44, 95 % CI 0.90-2.35, respectively). Restricting analyses to women >30 years further strengthened these associations.

CONCLUSIONS

While the small sample size limits inference, these findings show that altered DNA methylation at imprinted domains including IGF2/H19 and PEG1/MEST may mediate the association between HPV and ICC risk.

Associations between methylation of paternally expressed gene 3 (PEG3), cervical intraepithelial neoplasia and invasive cervical cancer

Cytology-based screening for invasive cervical cancer (ICC) lacks sensitivity and specificity to discriminate between cervical intraepithelial neoplasia (CIN) likely to persist or progress from cases likely to resolve. Genome-wide approaches have been used to identify DNA methylation marks associated with CIN persistence or progression. However, associations between DNA methylation marks and CIN or ICC remain weak and inconsistent. Between 2008-2009, we conducted a hospital-based, case-control study among 213 Tanzania women with CIN 1/2/3 or ICC. We collected questionnaire data, biopsies, peripheral blood, cervical scrapes, Human papillomavirus (HPV) and HIV-1 infection status. We assessed PEG3 methylation status by bisulfite pyrosequencing. Multinomial logistic regression was used to estimate odds ratios (OR) and confidence intervals (CI 95%) for associations between PEG3 methylation status and CIN or ICC. After adjusting for age, gravidity, hormonal contraceptive use and HPV infection, a 5% increase in PEG3 DNA methylation was associated with increased risk for ICC (OR = 1.6; 95% CI 1.2-2.1). HPV infection was associated with a higher risk of CIN1-3 (OR = 15.7; 95% CI 5.7-48.6) and ICC (OR = 29.5, 95% CI 6.3-38.4). Infection with high risk HPV was correlated with mean PEG3 differentially methylated regions (DMRs) methylation (r = 0.34 p<0.0001), while the correlation with low risk HPV infection was weaker (r = 0.16 p = 0.047). Although small sample size limits inference, these data support that PEG3 methylation status has potential as a molecular target for inclusion in CIN screening to improve prediction of progression. Impact statement: We present the first evidence that aberrant methylation of the PEG3 DMR is an important co-factor in the development of Invasive cervical carcinoma (ICC), especially among women infected with high risk HPV. Our results show that a five percent increase in DNA methylation of PEG3 is associated with a 1.6-fold increase ICC risk. Suggesting PEG3 methylation status may be useful as a molecular marker for CIN screening to improve prediction of cases likely to progress.

Distribution of HPV genotypes in cervical intraepithelial lesions and cervical cancer in Tanzanian women

Background

Infection with human papillomavirus (HPV) is associated with uterine cervical intraepithelial neoplasia (CIN) and invasive cancers (ICC). Approximately 80% of ICC cases are diagnosed in under-developed countries. Vaccine development relies on knowledge of HPV genotypes characteristic of LSIL, HSIL and cancer; however, these genotypes remain poorly characterized in many African countries. To contribute to the characterization of HPV genotypes in Northeastern Tanzania, we recruited 215 women from the Reproductive Health Clinic at Kilimanjaro Christian Medical Centre. Cervical scrapes and biopsies were obtained for cytology and HPV DNA detection.

Results

79 out of 215 (36.7%) enrolled participants tested positive for HPV DNA, with a large proportion being multiple infections (74%). The prevalence of HPV infection increased with lesion grade (14% in controls, 67% in CIN1 cases and 88% in CIN2-3). Among ICC cases, 89% had detectable HPV. Overall, 31 HPV genotypes were detected; the three most common HPV genotypes among ICC were HPV16, 35 and 45. In addition to these genotypes, co-infection with HPV18, 31, 33, 52, 58, 68 and 82 was found in 91% of ICC. Among women with CIN2-3, HPV53, 58 and 84/83 were the most common. HPV35, 45, 53/58/59 were the most common among CIN1 cases.

Conclusions

In women with no evidence of cytological abnormalities, the most prevalent genotypes were HPV58 with HPV16, 35, 52, 66 and 73 occurring equally. Although numerical constraints limit inference, findings that 91% of ICC harbor only a small number of HPV genotypes suggests that prevention efforts including vaccine development or adjuvant screening should focus on these genotypes.

Cervical human papillomavirus infection in accra, ghana

BACKGROUND

This study was aimed at estimating the human papillomavirus (HPV) prevalence and its determinants among a sample of Ghanaian women.

DESIGN

Cross-sectional observational study.

SETTING

Gynaecology outpatient clinic of the Korle-Bu Teaching Hospital, Accra, Ghana; the largest tertiary care gynaecology outpatient clinic in Ghana.

PARTICIPANTS

Convenient sample of 75 consenting women visiting the clinic.

METHODS

Information was obtained through personal interviews using structured questionnaire, Pap smears obtained, and laboratory testing of cervical exfoliated cells was performed. HPV DNA was detected using a GP5+/6+ polymerase chain reaction assay. These data were analyzed using both univariate and bivariate techniques.

RESULTS

The mean age of participants was 33.3 years (standard deviation, 9.2) and the percentage of lifetime monogamy was 21.3%. The crude HPV DNA prevalence was 10.7%. Unlike most populations studied so far, HPV prevalence was high not only among young women, but also in middle and old age. Independent HPV determinants were being illiterate (prevalence odds ratio [POR], 13.9; 95% confidence interval [95%CI], 1.9-100) and reporting more than three lifetime sexual partners (POR, 4.6; 95% CI, 1.0-22.2).

CONCLUSIONS

The study indicates a high crude prevalence of HPV in a largely polygamous Ghanaian population with a high crude prevalence in older age groups, which may be a distinctive feature of polygamous populations where HPV transmission continues into middle age and cervical cancer incidence is very high.

The prevalence of human papillomavirus infection in Mombasa, Kenya

OBJECTIVES

A human papillomavirus (HPV) prevalence survey was done in Mombasa, Kenya, to improve the knowledge of HPV prevalence and genotype distribution in sub-Saharan African countries overall, and in women of different ages.

METHODS

HPV prevalence was assessed using PCR in women older than 15 years attending family planning and mother-child care services.

RESULTS

Among 496 women, HPV prevalence was high (42.3%; 95% CI: 37.9-46.8; world age-standardized). Moreover, 46% of HPV-positive women harbored multiple-type infections. The most common types were HPV58 (10.5% of women), HPV16 (7.7%), HPV53 (6.7%), HPV18 (4.6%), and HPV6 (4.4%), and the prevalence of any high-risk HPV type was 28.8%. HPV prevalence was elevated among all age-groups (range 36.4-45.7%). Independent associations with HPV positivity were found for being in a polygamous marriage (OR = 1.7) and lifetime number of sexual partners (OR for ≥ 3 vs. 1 = 1.5), although they were of only borderline statistical significance.

CONCLUSIONS

These findings differ from other world regions, showing a high HPV burden in all age-groups with a high proportion of multiple-type infections. Our data strengthen the urgency of HPV vaccination in Kenya but also highlight the elevated number of women who would have positive results in an HPV-based screening program in the country.

Human papillomavirus infection and cervical cytology in HIV-infected and HIV-uninfected Rwandan women

BACKGROUND

Data on human papillomavirus (HPV) prevalence are essential for developing cost-effective cervical cancer prevention programs.

METHODS

In 2005, 710 human immunodeficiency virus (HIV)-positive and 226 HIV-negative Rwandan women enrolled in an observational prospective cohort study. Sociodemographic data, CD4+ cell counts, and cervical specimens were obtained. Cervicovaginal lavage specimens were collected from each woman and tested for >40 HPV types by a polymerase chain reaction assay; HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68 were considered primary carcinogenic HPV types.

RESULTS

The prevalence of HPV was higher in HIV-positive women than in HIV-negative women in all age groups. Among HIV-infected women, 69% were positive for >or=1 HPV type, 46% for a carcinogenic HPV type, and 10% for HPV-16. HPV prevalence peaked at 75% in the HIV-positive women aged 25-34 years and then declined with age to 37.5% in those >or=55 years old (Ptrend<.001). A significant trend of higher prevalence of HPV and carcinogenic HPV with lower CD4+ cell counts and increasing cytologic severity was seen among HIV-positive women.

CONCLUSIONS

We found a higher prevalence of HPV infection in HIV-positive than in HIV-negative Rwandan women, and the prevalence of HPV and carcinogenic HPV infection decreased with age.

Age-specific prevalence of infection with human papillomavirus in females: a global review

PURPOSE

Global data on age-specific prevalence of human papillomavirus (HPV) infection overall, and for high-risk HPV types 16 and 18, are essential for the future implementation of HPV prophylactic vaccines for cervical cancer prevention.

METHODS

A systematic review of peer-reviewed publications was conducted to summarize worldwide data on genital HPV-DNA prevalence in women. Studies with clear descriptions of polymerase chain reaction or hybrid capture detection assays were included.

RESULTS

A total of 346,160 women were included in 375 studies. Of 134 studies with age-stratified HPV prevalence data (116 low sexual risk populations, 18 high sexual risk populations), over 50% were from Europe and the Middle East (38%) and North America (19%), with smaller proportions from Asia and Australia (21%), Central and South America (11%), and Africa (10%). Across all geographical regions, data on HPV prevalence were generally limited to women over 18 years of age. Consistently across studies, HPV infection prevalence decreased with increasing age from a peak prevalence in younger women (< or =25 years of age). In middle-aged women (35-50 years), maximum HPV prevalence differed across geographical regions: Africa (approximately 20%), Asia/Australia (approximately 15%), Central and South America (approximately 20%), North America (approximately 20%), Southern Europe/Middle East (approximately 15%), and Northern Europe (approximately 15%). Inconsistent trends in HPV prevalence by age were noted in older women, with a decrease or plateau of HPV prevalence in older ages in most studies, whereas others showed an increase of HPV prevalence in older ages. Similar trends of HPV 16 and/or 18 prevalence by age were noted among 12 populations with available data.

DISCUSSION

Genital HPV infection in women is predominantly acquired in adolescence, and peak prevalence in middle-aged women appears to differ across geographical regions. Worldwide variations in HPV prevalence across age appear to largely reflect differences in sexual behavior across geographical regions. Further studies of HPV prevalence in adolescents are needed for all geographic regions.

The prevalence of cervical HPV and cytological abnormalities in association with reproductive factors of rural Nigerian women

OBJECTIVE

To estimate the prevalence of cervical human papillomavirus (HPV) and cytological abnormalities while addressing demographic and reproductive variables in a sample of rural Nigerian patients.

METHODS

In March 2004, a medical project was conducted in Okene, Nigeria. The obstetrics/gynecology team collected demographics of 231 patients and 199 ThinPrep Pap smears (Cytyc, Marlborough, MA), which were analyzed cytologically and for the presence of HPV DNA.

RESULTS

Of 231 patients (mean age 32.2), 76% had seen a physician four times or less. From 199 Pap smears performed, 21.6% had high-risk (HR) HPV, low-risk (LR) HPV, or both. HR HPV was present in 16.6% of the women. There were 13 (6.5%) abnormal Pap smears, of which 9 (4.5%) had atypical squamous cells of undetermined significance (ASCUS), 1 (0.5%) had atypical glandular cells (AGC), 2 (1%) had low-grade squamous intraepithelial lesions (LSIL), and 1 (0.5%) had a high-grade SIL (HSIL). Other findings were Trichomonas vaginalis in 18 patients (9%) and Candida in 27 patients (13.5%).

CONCLUSIONS

The prevalence of cervical HPV and SIL in Okene, Nigeria, is consistent with reports from other African regions. Improved access to healthcare and cervical cancer screening programs may help to decrease transmission of HPV and subsequent cervical cancer in underprivileged areas.

Prevalence of human papillomavirus genotypes and their variants in high risk West Africa women immigrants in South Italy

BACKGROUND

The distribution of human papillomaviruses (HPVs) varies greatly across populations and HPV surveys have been performed in different geographical regions in order to apply appropriate vaccine strategies. Little information, however, exists regarding HPV genotypes distribution in immigrant women from countries at high incidence for cervical cancer. The aim of this study was to determine the spectrum of HPVs and their variants among HIV-positive and HIV-negative women immigrants in South Italy mainly from West Africa and with a history of prostitution.

RESULTS

Cervical cytological samples have been collected from 14 HIV-positive and 31 HIV-negative immigrants (38 out of 45 were born in Nigeria), attending a gynecological outpatient clinic in the Campania region. Human papillomaviruses were detected by broad spectrum consensus-primer-pairs MY09/MY11 and GP5+/GP6+-based polymerase chain reaction and characterized by nucleotide sequence analysis. Altogether, 42.2% (19/45) of samples were HPV positive with detection rates of 57.1% (8/14) in HIV-positive and 35.5% (11/31) in HIV-negative women. Among the twelve different viral genotypes identified, HPV33, 58, 70 and 81 were the prevalent genotypes with a frequency of 6.7% each, followed by HPV16, 35, 42, 54, 31, 52, 56 and 67, in descending order of prevalence. Sequence homology studies performed on the L1 amplified fragments of HPV16, 52 and 58 isolates allowed the identification of nucleotide changes distinctive of non-European variants.

CONCLUSION

The overall HPV prevalence (42.2%) was high in this immigrant women group with the most common viral types other than HPV16 and 18, against which current vaccine strategies have been developed. The distribution of HPV genotypes and their variants in high-risk immigrants reflects that of their original countries. The surveillance of risk groups that may act as viral reservoirs of uncommon genotypes within different countries are necessary to determine the severity of HPV infection with the different viral types and to monitor a possible shift of prevalent strains following vaccination.

Oncogenic human papillomavirus (HPV) type distribution and HPV type 16 E6 variants in two Spanish population groups with different levels of HPV infection risk

The aim of this study is to determine oncogenic human papillomavirus (HPV) types and HPV type 16 (HPV16) variant distribution in two Spanish population groups, commercial sex workers and imprisoned women (CSW/IPW) and the general population. A multicenter cross-sectional study of 1,889 women from five clinical settings in two Spanish cities was conducted from May to November 2004. Oncogenic HPV infection was tested by an Hybrid Capture II (HC2) test, and positive samples were genotyped by direct sequencing using three different primer sets in L1 (MY09/11 and GP5+/GP6+) and E6/E7. HPV16 variants were identified by sequencing the E6, E2, and L1 regions. Four hundred twenty-five samples were positive for the HC2 test, 31.5% from CSW/IPW and 10.7% from the general population. HPV16 was the most frequent type. Distinct profiles of oncogenic HPV type prevalence were observed across the two populations. In order of decreasing frequency, HPV types 16, 31, 58, 66, 56, and 18 were most frequent in CSW/IPW women, and types 16, 31, 52, 68, 51, and 53 were most frequent in the general population. We analyzed HPV16 intratype variants, and a large majority (78.7%) belonged to the European lineage. AA variants were detected in 16.0% of cases. African variants belonging to classes Af1 (4.0%) and Af2 (1.3%) were detected. Different HPV types and HPV16 intratype variants are involved in oncogenic HPV infections in our population. These results suggest that HPV type distribution differs in CSW/IPW women and in the general population, although further analysis is necessary.

Human papillomavirus genotype distribution and cervical squamous intraepithelial lesions among high-risk women with and without HIV-1 infection in Burkina Faso

Human papillomavirus (HPV) infection and cervical squamous intraepithelial lesions (SILs) were studied in 379 high-risk women. Human papillomavirus DNA was detected in 238 of 360 (66.1%) of the beta-globin-positive cervical samples, and 467 HPV isolates belonging to 35 types were identified. Multiple (2-7 types) HPV infections were observed in 52.9% of HPV-infected women. The most prevalent HPV types were HPV-52 (14.7%), HPV-35 (9.4%), HPV-58 (9.4%), HPV-51 (8.6%), HPV-16 (7.8%), HPV-31 (7.5%), HPV-53 (6.7%), and HPV-18 (6.4%). Human immunodeficiency virus type 1 (HIV-1) seroprevalence was 36.0%. Human papillomavirus prevalence was significantly higher in HIV-1-infected women (87 vs 54%, prevalence ratio (PR) = 1.61, 95% confidence interval (CI): 1.4-1.8). High-risk HPV types (71 vs 40%, PR = 1.79, 95% CI: 1.5-2.2), in particular HPV-16+18 (22 vs 9%, PR = 2.35, 95% CI: 1.4-4.0), and multiple HPV infections (56 vs 23%, PR = 2.45, 95% CI: 1.8-3.3) were more prevalent in HIV-1-infected women. High-grade SIL (HSIL) was identified in 3.8% of the women. Human immunodeficiency virus type 1 infection was strongly associated with presence of HSIL (adjusted odds ratio = 17.0; 95% CI 2.2-134.1, P = 0.007) after controlling for high-risk HPV infection and other risk factors for HSIL. Nine of 14 (63%) HSIL cases were associated with HPV-16 or HPV-18 infection, and might have been prevented by an effective HPV-16/18 vaccine.

Cervical human papillomavirus infection and squamous intraepithelial lesions in rural Gambia, West Africa: viral sequence analysis and epidemiology

The development of effective strategies against cervical cancer in Africa requires accurate type specific data on human papillomavirus (HPV) prevalence, including determination of DNA sequences in order to maximise local vaccine efficacy. We have investigated cervical HPV infection and squamous intraepithelial lesions (SIL) in an unselected cohort of 1061 women in a rural Gambian community. Squamous intraepithelial lesions was diagnosed using cytology and histology, HPV was typed by PCR-ELISA of DNA extracts, which were also DNA sequenced. The prevalence of cervical HPV infection was 13% and SIL were observed in 7% of subjects. Human papillomavirus-16 was most prevalent and most strongly associated with SIL. Also common were HPV-18, -33, -58 and, notably, -35. Human papillomavirus DNA sequencing revealed HPV-16 samples to be exclusively African type 1 (Af1). Subjects of the Wolof ethnic group had a lower prevalence of HPV infection while subjects aged 25-44 years had a higher prevalence of cervical precancer than older or younger subjects. This first report of HPV prevalence in an unselected, unscreened rural population confirms high rates of SIL and HPV infection in West Africa. This study has implications for the vaccination of Gambian and other African populations in the prevention of cervical cancer.

High prevalence of high-risk oncogenic human papillomaviruses harboring atypical distribution in women of childbearing age living in Libreville, Gabon

The extent of human papillomavirus (HPV) genital shedding and type-specific diversity were evaluated in 354 consecutive women of childbearing age living in Libreville, Gabon. Detection of HPV DNA was performed by PCR using the MY09/MY11 primer set on DNA extracted from endocervical swabs. All PCR positive specimens were subjected to direct sequencing and HPV genotypes were identified on the basis of >95% sequence homology in the L1 region. Reverse line blot hybridization assay was used when a genotype could not be resolved by sequencing alone. HPV DNA was detected in 163 (46%) women, all clinically asymptomatic for HPV-related lesions. The highest prevalence of genital HPV detection (45%) was in the age group from 22 to 29 years. A total of 90 women (55%) harbored high-risk (HR) genotypes, with the most common being HPV-53 (19; 12%), HPV-58 (17; 11%), and HPV-16 (16; 10%). Low-risk genotypes were found in 36 (22%) women with HPV-54 and HPV-70 being the most frequently detected (17; 11% and 10; 6%, respectively). Finally 37 women (23%) tested positive for genotypes of unknown oncogenic risk, the most common in this category being HPV-83 (20; 12%). Multiple infections were detected in 35 (21%) women. By multivariate analysis, HPV genital shedding was significantly associated with young age (OR: 0.34; P < 0.007). The multivalent vaccine currently available against cervical carcinomas, is only active against HPV-16 and HPV-18, and will thus have a low impact in this setting.

Prevalence of papillomavirus infection in women in Ibadan, Nigeria: a population-based study

To investigate the prevalence of and the risk factors for cervical infection with human papillomavirus (HPV) in an inner-city area of Ibadan, Nigeria, we interviewed and obtained a sample of cervical cells from 932 sexually active women aged 15 years or older. A total of 32 different HPV types were identified with an HPV prevalence of 26.3% overall and 24.8% among women without cervical lesions; or age-standardised to the world standard population of 28.3 and 27.3%, respectively. High-risk HPV types predominated, most notably HPV 16, 31, 35 and 58. In all, 33.5% of infections involved more than one HPV type. Unlike most populations studied so far, HPV prevalence was high not only among young women, but also in middle and old age. Single women (odds ratio, OR=2.1; 95% confidence interval, CI=1.1–3.9) and illiterate women (OR=1.7; 95%CI=1.1–2.5) showed increased HPV positivity. Associations were also found with anti-Herpes simplex-2 antibodies (OR=1.6; 95% CI: 1.1–2.1) and with the husband's extramarital relationships (OR=1.6: 95% CI: 1.0–2.6). High prevalence of HPV in all age groups may be a distinctive feature of populations where HPV transmission continues into middle age and cervical cancer incidence is very high.

Human papillomavirus in a rural community in Zimbabwe: The impact of HIV co-infection on HPV genotype distribution

Cervical cancer is a leading cause of cancer-related deaths in developing countries, and the human papillomavirus (HPV) is linked etiologically to cervical cancer. Hence, a vaccine which prevents HPV-associated cervical cancer would have the most impact in developing countries, including the African continent. The type-specific immune response towards HPV virus-like particles, in combination with geographical variation in the prevalence of HPV, necessitates the presence of multiple HPV type antigens in a single vaccine cocktail in order to provide relevant protection. We aimed to investigate whether co-infection with HIV, which is highly prevalent in Africa, plays a role in HPV genotype distribution. After informed consent, HPV detection by GP5+/6+ PCR and HIV detection by serology was carried out on 236 women from the rural north-western part of Zimbabwe. The prevalence of HPV was higher in HIV positive women (54%) than in HIV negative women (27%). Certain HPV types (HPV types 11, 39, 43, 51, and 59, P-values ranging from 0.017 to 0.067) occurred more frequently in HIV positive women. Only high-risk HPV, and not HIV, was associated significantly with cervical intraepithelial neoplasia in multiple regression analysis. In conclusion, a high prevalence of HPV was found in a rural community, where regular Papanicolaou (Pap) smears would be a logistic and economic impossibility, but where free vaccination programmes against other infections are already established. The results suggest that HIV co-infection may have an impact on HPV genotype distribution.

Prevalence of human papillomavirus genotypes in women from three clinical settings

Prevalence of 27 human papillomavirus (HPV) genotypes was assessed in 1,331 women in three clinical settings: Family planning clinic (low-risk HIV-, n = 202, 21.3% HPV+), colposcopy clinic (high-risk HIV-, n = 854, 34.3% HPV+), and HIV outpatient clinic (HIV+, n = 275, 48.7% HPV+). Compared to women from both family planning and colposcopy clinics, HIV+ women revealed significantly higher prevalence of infection with oncogenic, non-oncogenic, and multiple HPV types. HPV types 52 and 51 were most prevalent in the low-risk HIV- women, whereas in the high-risk HIV- women, HPV types 16, 52, 58, and 35 were most prevalent. Interestingly, in the HIV+ women, less characterized types 83, 53, and 54 were most prevalent. The distinct profiles of genotype prevalence persisted after stratification by Pap smear status. After adjustment for concurrent infections with other types, HPV type 51 in the low-risk HIV- women, and types 16, 35, 39, 45, 52, and 58 in the high-risk HIV- women were significantly associated with cytologic abnormalities (exact P < 0.05). In HIV+ women across CD4 cell count strata, HPV types 42, 16, and 82 revealed significant decreasing trends with increasing CD4 counts (exact P for trend < 0.05). These data suggest distinct genotypic prevalence profiles in women at diverse risk for cervical cancer. The association of several genotypes with cytologic abnormalities underscores the need for vaccines targeting a wide range of HPV types.

Genital human papillomavirus genotypes in northwestern Tanzania

Using MY09-MY11 PCR and human papillomavirus (HPV) typing by reverse blot hybridization, we found a 34% cervical HPV prevalence among 561 pregnant women in Tanzania. One hundred three of 123 women (84%) with typeable samples harbored high-risk oncogenic strains. HPV type 16 (HPV-16) was the most prevalent subtype (18%) among HPV-infected women and among women with cervical neoplasia (3 of 19). A multivalent vaccine for HPV-16, -18, -31, -33, and -35 would be necessary to prevent 50% of the neoplasia in this population.