Epidemiology Of Human Papillomavirus Infection Research Articles

Human Papillomavirus (HPV) Prevalence and Types among Women Attending Regular Gynecological Visit in Tehran, Iran

Persistent infection by HPV is now recognized as the main cause of cervical cancer. HPV prevalence data is not yet available in Iran. This study is organized to evaluate type-specific HPV prevalence and to compare it with Pap smear results among Iranian women attending regular gynecological visits. A total of 851 women aged 18 - 65 years, attending regular gynecological visits, were retrospectively evaluated. HPV detection and genotyping was performed by use of Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP). Cytological evaluation was done by Papanicolaou method and the association between cytological results and HPV status was analyzed. 19 different HPV types were detected in 265 of the 851 specimens (31.1%). Overall HPV infection as well as infection with High Risk (HR) HPV types was highest in women aged 18 - 25 years and decreased with age. Type-specific prevalence of HPV-16 and 18 was 7.3% and 2.8%, respectively, and a large number of women (20.2%) were infected by HR HPV types other than HPV-16 and/or HPV-18. There was also an upward trend in the prevalence of HR HPV infections as the abnormality in cytology increased. The prevalence of HPV co-infection was 29.1% of HPV positive patients and declined from LSIL (18.2%) to HSIL (3.9%). Our study indicated that the burden of HPV infection among Iranian females was higher in comparison with previous estimates reported from Iran. Furthermore, higher prevalence of premalignant changes in Iranian women infected with HR HPV types, other than vaccine types, should be considered in immunization programs and development of population-specific HPV vaccines. This remarkable difference in prevalence of HPV types among previous studies, confirms our need to further investigations on epidemiology of HPV infection in Iran.

Prevalence and Distribution of Human Papillomavirus Infection in Korean Women as Determined by Restriction Fragment Mass Polymorphism Assay

The development of a prophylactic vaccine that targets human papillomaviruses (HPV) 6, 11, 16, and 18 to prevent cervical cancer has increased interest in the ethnic and geographical distributions of HPV genotypes. We investigated HPV prevalence and type distribution by restriction fragment mass polymorphism (RFMP) testing a total of 60,775 specimens (aged 18-79 yr, median 44) taken from liquid-based cytology. Overall HPV positive rate of total patients was 34.2%. Among the positive patients, 87.7% was single type infections, and 12.3% was multiple HPV types. HPV-16 was the most prevalent genotype observed in 2,307 (26.0%), followed by type 52 in 2,269 (25.5%), type 58 in 1,090 (12.3%), type 18 in 633 (7.1%), type 56 in 436 (4.9%). The pattern of high risk-HPV positive rate according to age showed U-shape with a peak in HPV prevalence among women less than 30 yr of age, and a second peak among the older females aged 70 to 79 yr. The leading four high-risk HPV genotypes were HPV-16, HPV-52, HPV-58, and HPV-18 in descending order. In conclusion, this study provides the most representative prevalence and type-specific distribution of HPV among Korean women, and demonstrates that the epidemiology of HPV infection is different from that of other regions of the world.

The epidemiology of human papillomavirus infection in HIV-positive and HIV-negative high-risk women in Kigali, Rwanda

BackgroundThe prevalence, incidence and persistence of human papillomavirus (HPV) types in sub-Saharan Africa are not well established. The objectives of the current study are to describe (predictors of) the epidemiology of HPV among high-risk women in Kigali, Rwanda.MethodsHIV-negative, high-risk women were seen quarterly for one year, and once in Year 2. HIV serostatus, clinical, and behavioral information were assessed at each visit, HPV types at Month 6 and Year 2, and other sexually transmitted infections (STI) at selected visits. HPV prevalence was also assessed in HIV-positive, high-risk women.ResultsPrevalence of any HPV was 47.0% in HIV-negative women (median age 25 years) compared to 72.2% in HIV-positive women (median age 27 years; OR 2.9, 95% CI 1.9-4.6). Among HIV-negative women, cumulative incidence of high-risk (HR)-HPV was 28.0% and persistence 32.0% after a mean period of 16.6 and 16.9 months, respectively. Prior Chlamydia trachomatis and Neisseria gonorrhoeae infection, concurrent low-risk (LR)-HPV infection and incident HSV-2 were associated with HR-HPV prevalence among HIV-negative women; prior C. trachomatis infection and co-infection with LR-HPV and HPV16-related HPV types with HR-HPV acquisition. HPV16-related types were the most prevalent and persistent.ConclusionsHigh HPV prevalence, incidence and persistence were found among high-risk women in Kigali. HPV52 had the highest incidence; and, together with HPV33 and HPV58, were strongly associated with acquisition of other HR-HPV types in HIV-negative women.

Prevalence of human papillomavirus infection in women in Benin, West Africa

BackgroundCervical cancer ranks as the first most frequent cancer among women in Benin. The major cause of cervical cancer now recognized is persistent infection of Human Papillomavirus (HPV). In Benin there is a lack of screening programs for prevention of cervical cancer and little information exists regarding HPV genotype distribution.MethodsCervical cells from 725 women were examined for the presence of viral DNA by means of a polymerase chain reaction (PCR) multiplex-based assay with the amplification of a fragment of L1 region and of E6/E7 region of the HPV genome, and of abnormal cytology by Papanicolaou method. The association between HPV status and Pap test reports was evaluated. Socio-demographic and reproductive characteristics were also related.ResultsA total of 18 different HPV types were identified, with a prevalence of 33.2% overall, and 52% and 26.7% among women with and without cervical lesions, respectively. Multiple HPV infections were observed in 40.2% of HPV-infected women. In the HPV-testing group, the odds ratio for the detection of abnormal cytology was 2.98 (95% CI, 1.83-4.84) for HPV positive in comparison to HPV negative women. High risk types were involved in 88% of infections, most notably HPV-59, HPV-35, HPV-16, HPV-18, HPV-58 and HPV-45. In multiple infections of women with cytological abnormalities HPV-45 predominated.ConclusionsThis study provides the first estimates of the prevalence of HPV and type-specific distribution among women from Benin and demonstrates that the epidemiology of HPV infection in Benin is different from that of other world regions. Specific area vaccinations may be needed to prevent cervical cancer and the other HPV-related diseases.

Pre‐vaccination epidemiology of human papillomavirus infections in Japanese women with abnormal cytology

To investigate the pre-vaccination epidemiology of genital human papillomavirus (HPV) infections and genotypes in women with abnormal cytology in Nagasaki, Japan. We performed Pap smear tests, biopsies and HPV genotype testing in Nagasaki Prefecture from August 2007 through November 2009. During the study period, serial samples of uterine cervical specimens were obtained from 539 subjects with abnormal cytology and/or squamous intraepithelial lesions (SIL) confirmed previously, or with clinically suspected invasive cervical cancer. In 119 HPV-positive subjects with low-grade SIL, the three most prevalent high-risk HPV genotypes were HPV52 (21.8%; 26/119), HPV16 (20.2%; 24/119) and HPV56 (17.6%; 21/119). In 199 women, 127 HPV-positive subjects with high-grade SIL and 67 HPV-positive subjects with squamous cell carcinoma (SCC), the three most prevalent high-risk HPV genotypes were HPV16 (44.3%; 86/194), HPV52 (20.6%; 40/194) and HPV58 (16.0%; 31/194). Compared with the distribution of high-risk HPV genotypes in other countries, HPV52 was a more common genotype in Nagasaki. With disease progression to SCC, the distribution of high-risk HPV56 belonging to the A6 HPV family decreased, while HPV16 and HPV52 belonging to the A9 HPV family persisted. Our data provide an important resource to address the case for vaccination against HPV genotypes other than HPV16 and HPV18 in Japan.

Human papillomavirus, cancer and vaccination

HIV-positive men and women are at greater risk of human papillomavirus (HPV)-related cancers compared with the general population. This study describes recent findings in HPV-related cancers and precancerous lesions and discuss the potential benefit of recently developed prophylactic HPV vaccines. Despite improving access to antiretroviral therapy (ART), particularly in developing countries, the incidence of cervical cancer has not declined and the incidence of anal cancer is still rising in HIV-infected individuals. HIV appears to affect the history of HPV infection, and the distribution of genotypes detected in precancerous lesions in HIV-infected women is not similar to that of the general population. The use of the quadrivalent HPV vaccine has been shown to prevent cervical precursor lesions caused by the vaccine types in women in the general population. Safety and immunogenicity studies of the quadrivalent HPV vaccine in HIV-infected individuals are underway. Efficacy has to be proven in the context of both a different epidemiology of HPV infection and of immunosuppression. Recent data imply that the issue of HPV-related cancers will not decline in HIV-infected individuals. Therefore, efficacy studies of HPV vaccines are sorely needed in the setting of HIV.

Seroprevalence of human papillomavirus 6, 11, 16, and 18 in young primiparous women in Sao Paulo, Brazil.

Data on epidemiology of HPV infection are needed for the development of human papillomavirus (HPV) vaccine recommendations, especially in countries where HPV vaccination is not yet included in public vaccination programs. The aim of this study was to determine the prevalence of serum antibodies to HPV types 6, 11, 16, and 18 and associated factors among young women after birth of the first child. This cross-sectional study was carried out in a large public maternity hospital in Sao Paulo, Brazil. Three hundred one women aged 15 to 24 years who gave birth to their first child were recruited between 43 and 60 days after delivery. Seroprevalence was performed using a type-specific enzyme-linked immunosorbent assay based on HPV Late protein 1 viruslike particles. The association of seroreactivity with these 4 HPV types with selected demographic and behavioral factors was assessed by Generalized Linear Model analysis. Fifty-eight (19.3%) women (95% confidence interval, 15.0%-24.2%) had antibodies to any of the 4 viruslike particles tested. The overall seroprevalence rates of the HPV types were: HPV16, 9.0%; HPV18, 7.0%; and HPV 6+11, 7.7%, which are targeted by the HPV prophylactic vaccines. In the multivariate analysis, only age (inversely, P = 0.044 for trend) and previous sexually transmitted disease (P = 0.008) were 2 factors independently associated with HPV seropositivity. These data offer additional information on the epidemiology of HPV in a group of young Brazilian women after first delivery and contribute to establish a baseline of HPV seroprevalence against which post-HPV vaccine era seroprevalence can be compared.

The human papillomavirus (HPV) vaccine, HPV related diseases and cervical cancer in the post-reproductive years

Prophylactic HPV vaccines have demonstrated high efficacy against a range of HPV related diseases. They have been widely adopted as population health interventions in many jurisdictions and their routine use has been endorsed by the WHO. The development of these vaccines comes after an increased understanding of the natural history and epidemiology of HPV infection and disease in both males and females. Persistent HPV infection with oncogenic types induces malignant transformation in a range of epithelia including the cervix, anogenital regions, the penis and a number of head and neck sites. In relation to HPV disease prevention in the post-reproductive years, most infections occur soon after commencement of sexual activity but new infections do occur throughout the age spectrum. This reduces the likely impact of prophylactic vaccines in this population. The major impact on HPV related disease in this age group will come from advances in screening and early detection of HPV and neoplastic precursors. The most appropriate prevention for any individual man or women in this age group will be an individualised combination of vaccination, screening and early detection depending on the individual's own circumstances.

Human Papillomavirus Infection: Low-Risk and High-Risk Genotypes in Women in Catania, Sicily

Human papillomavirus (HPV) infection has been strongly and consistently associated with cervical carcinoma and its cytologic precursors, such as squamous intraepithelial lesions. A cross-sectional survey was conducted with the aim of estimating the prevalence of cervical HPV infection in women attending a service of colposcopy in Catania, Eastern Sicily, Italy. The prevalence of type-specific HPV was examined in women with negative colposcopic results and cervical intraepithelial neoplasia grades 1, 2, or 3, with the aim of providing some cross-sectional figures on the local epidemiology of HPV infection. Human papillomavirus DNA was found in 62.1% of women with negative colposcopic results and in 73.2% with positive colposcopic results. Among high-risk types, a predominance of HPV-16 (51.5% of infected women) was shown followed by HPV-56 (29.7%). An age-related pattern was described with a peak in HPV prevalence among women younger than 25 years, followed by the expected decline in prevalence and a second characteristic peak in the perimenopausal or postmenopausal years, useful to design future control strategies. The age-related pattern of HPV prevalence and the presence of uncommon high-risk genotypes and their role in the pathogenesis of cervical cancer need to be addressed by specific epidemiologic studies to design large-scale screening programs and multivalent vaccine strategies.

Human papillomavirus vaccine and adolescents

The present review describes recent advances in our understanding about the epidemiology of human papillomavirus infection among female adolescents and describes several adolescent-specific issues related to administering human papillomavirus vaccines. National estimates demonstrate that human papillomavirus infection is most prevalent among adolescents and young adults. Parents, patients, and providers have a high interest in vaccination against this virus, but current patterns of adolescent healthcare utilization suggest that changes in adolescent preventive care delivery may be needed to provide these vaccines in a timely manner. Debate over whether adolescents should be legally allowed to self-consent to vaccination is another issue that remains unresolved and could have a substantial impact on vaccination rates. Legislation on school entry requirements related to human papillomavirus vaccination has been introduced in many states as a mechanism to circumvent some of these concerns, but the details of this legislation and its effect on adolescent vaccine utilization remain to be determined. Female adolescents are at a high risk for human papillomavirus infection and are likely to derive significant benefits from vaccination against this virus. However, administering human papillomavirus vaccines to this age group will require providers to be familiar with several issues unique to the adolescent population.

Epidemiology of Human Papillomavirus Infection in Men, Cancers other than Cervical and Benign Conditions

Human papillomavirus (HPV) infection is commonly found in the genital tract of men and women with or without any clinical lesion. The association of HPV DNA with several different ano-genital cancers other than cervical has been reported for the vulva, vagina, anus and penis. HPV DNA has also been identified in head and neck cancers in the oral cavity, the oropharynx and the larynx in both sexes. In men, 80-85% of anal cancers and close to 50% of penile cancers are associated with HPV infection. In women, HPV DNA is prevalent in 36–40% vulvar cancer cases and close to 90% of vaginal cancers. There is limited data available on the natural history and HPV-related diseases in the genital tract in men, although studies are ongoing. Efficacy of HPV vaccines in the prevention of HPV infection and disease among men also remains unknown. Among HPV DNA positive ano-genital cancer cases, HPV-16 is the most frequently found followed distantly by HPV-18. In benign HPV-related diseases such as genital warts or recurrent respiratory papillomatosis HPV-6 and 11, the two most frequent non-oncogenic types, are the predominant types detected. Oncogenic types are rarely detected. In this article we summarize and review studies describing the natural history of HPV infections among men and its impact on HPV related disease in women. We summarize the evidence linking HPV in the epidemiology and etiology of cancers of the vulva, vagina, anus and oropharynx and present recent estimates of the burden of and HPV type distribution in genital warts and in cases of HPV infection of the airways.

Epidemiology of Human Papillomavirus Infection and Cervical Cancer and Future Perspectives in Hong Kong, Singapore and Taiwan

Hong Kong, Singapore and Taiwan are three island states that are newly emerged affluent economic areas in Asia. The majority of the populations are ethnically Chinese with a total population of 6.98, 4.5 and 23 million, respectively. Cervical cancer has been declining over the last thirty years in all three states and is largely attributable to widespread opportunistic cervical cancer screening. The age-standardized incidence rates of cervical cancer are 9.6 per 100,000 women in Hong Kong in 2004, 10.6 per 100,000 women in Singapore in 2002 and 18.6 per 100,000 women in Taiwan in 2003. High prevalence of human papillomavirus (HPV) was observed in all three states. In cervical cancer, HPV 16 and 18 are the two most prevalent HPV types, but HPV 58 and 52 are also highly prevalent in these three states. Important epidemiological risk factors for invasive cervical cancer include smoking and age at sexual debut for women, although this is changing towards an earlier age. Of the three states, Taiwan was the first to have a comprehensive national screening programme in 1995 followed by Hong Kong in 2002 and Singapore in 2004. Women in these three states are well aware of cervical cancer and the preventative means by Pap smear screening, although their awareness and understanding of the role of HPV in cervical carcinogenesis is low. Prophylactic HPV vaccines have been licensed in the three states. Routine comprehensive public vaccination programme for adolescent girls has yet to be adopted by the governmental agency, despite an affirmative recommendation by medical professional bodies.

Epidemiology of human papillomavirus infection among fishermen along Lake Victoria Shore in the Kisumu District, Kenya

Objectives:The epidemiology of human papillomavirus (HPV) infection in men in Kenya is largely uncharacterised. We set out to determine the prevalence and determinants of HPV infection among sexually active fishermen...

The Epidemiology of Human Papillomavirus Infection and Cervical Cancer

Cervical cancer has been recognized as a rare outcome of a common Sexually Transmitted Infection (STI). The etiologic association is restricted to a limited number of viral types of the family of the Human Papillomaviruses (HPVs). The association is causal in nature and under optimal testing systems, HPV DNA can be identified in all specimens of invasive cervical cancer. As a consequence, it has been claimed that HPV infection is a necessary cause of cervical cancer. The evidence is consistent worldwide and implies both the Squamous Cell Carcinomas (SCC), the adenocarcinomas and the vast majority (i.e. > 95%) of the immediate precursors, namely High Grade Squamous Intraepithelial Lesions (HSIL)/Cervical Intraepithelial Neoplasia 3 (CIN3)/Carcinoma in situ. Co-factors that modify the risk among HPV DNA positive women include the use of oral contraceptives (OC) for five or more years, smoking, high parity (five or more full term pregnancies) and previous exposure to other sexually transmitted diseases such as Chlamydia Trachomatis (CT) and Herpes Simplex Virus type 2 (HSV-2). Women exposed to the Human Immunodeficiency Virus (HIV) are at high risk for HPV infection, HPV DNA persistency and progression of HPV lesions to cervical cancer.

CHAPTER 2 The epidemiology of human papillomavirus infection and its association with cervical cancer

Cervical cancer has been recognized as a rare outcome of a common, sexually transmitted infection whose etiologic association is restricted to a few human papillomavirus (HPV) types. With optimal testing systems HPV DNA can be identified in nearly all specimens of invasive cervical cancer, and it is claimed that infection of the cervix with HPV is a necessary cause of cervical cancer. The evidence is consistent worldwide for squamous cell carcinomas (SCC), adenocarcinomas, and the vast majority (>95%) of the immediate cervical cancer precursors, namely high-grade squamous intraepithelial lesions (HSILs)—also known as cervical intraepithelial neoplasia 3 (CIN 3) or carcinoma in situ. Cofactors that modify the risk for HPV DNA-positive women include the use of oral contraceptives (OCs) for 5 or more years, smoking, high parity (5 or more full-term pregnancies), and previ-ous exposure to other sexually transmitted diseases such as Chlamydia trachomatis and herpes simplex virus type 2 (HSV-2). Women exposed to the human immuno-deficiency virus (HIV) are at high risk for HPV infection, HPV DNA persistence, and progression of HPV lesions to cervical cancer.

The development of cervical cancer and its precursors: what is the role of human papillomavirus infection?

Human papillomavirus (HPV) is a significant health care burden in the United States. The majority of sexually active men and women will be infected with HPV at some point in their lives and are subject to developing human papillomavirus-associated disease. Current estimates suggest that 20 million Americans are currently infected, and more than 5 million new infections occur each year. The prevalence of human papillomavirus is highest in populations in their late teens and early twenties, with nearly half of all new human papillomavirus infections occurring within 3 years of first intercourse. HPV is the necessary cause of genital warts, cervical intraepithelial neoplasia, and invasive cervical cancer. As such, human papillomavirus is responsible for significant medical morbidity and health care costs. Screening with cervical cytology has significantly reduced mortality rates; however, approximately 3900 women will die in 2005 from cervical cancer in the United States. Human papillomavirus DNA testing has shown promise in identifying high-grade abnormalities as an adjunct to traditional cytology, and should be used according to guidelines established by the American Cancer Society and the American College of Obstetricians and Gynecologists. The epidemiology of HPV infection and a brief introduction to the natural history of HPV infection will be presented here.

Evidence of human papilloma virus infection and its epidemiology in esophageal squamous cell carcinoma.

To look for the evidence of human papilloma virus (HPV) infection in esophageal squamous cell carcinomas (ESCC) and to investigate the potential role and epidemiology of HPV infection in the pathogenesis of esophageal carcinomas in Henan emigrants. Papilloma virus(PV) and HPV were determined by Ultrasensive S-P immunohistochemistry (IHC) and in situ hybridization (ISH)in esophageal carcinoma tissues (82 cases) and the normal mucosa (40 cases). IHC revealed that the positive rate of PV was 75.0%, 68.18% and 72.5% respectively while the HPV (16/18-E6) positive rate was 45.0%,36.36%, 37.5%, respectively in esophageal carcinoma tissue specimens from Henan emigrants,the local citizens and patients in Hubei Cancer Hospital. The PV and HPV (16/18-E6) were negative in all normal esophageal mucosa specimens. No correlation was found between HPV in esophageal squamous cell carcinoma tissues and in grade 1-3 esophageal squamous cell carcinoma cells. In situ hybridization showed that the HPV (16/18) DNA positive rate was 30.0%, 31.8%, 25.0%, respectively in the 3 groups of samples. No positive hybridization signal was found in 40 normal esophageal mucosa specimens. The positive rate of HPV (16/18) DNA in the esophageal carcinoma specimens was significantly higher than that in normal mucosa specimens (P<0.05). The positive rate was not different among the 3 groups of esophageal carcinoma tissue specimens (P>0.05). HPV infection is high in esophageal carcinoma of Henan emigrants, local residents and patients in Hubei Cancer Hospital.HPV is closely related with esophageal squamous cell carcinoma. HPV infection may play an important role in esophageal squamous cell carcinoma.

Epidemiology of HPV infection among Mexican women with normal cervical cytology.

Cervical cancer is caused by human papillomavirus (HPV) and is the most common cancer among Mexican women, but no population-based studies have reported the prevalence and determinants of HPV infection in Mexico. A population-based study was carried out between 1996 and 1999, based on an age-stratified random sample of 1,340 women with normal cytologic diagnoses from 33 municipalities of Morelos State, Mexico. The prevalence of cervical HPV DNA was determined by reverse line blot strip assay to detect 17 cancer-associated and 10 non-cancer-associated HPV types. Two peaks of HPV DNA prevalence were observed. A first peak of 16.7% was observed in the age group under 25 years. HPV DNA prevalence declined to 3.7% in the age group 35-44 years, then increased progressively to 23% among women 65 years and older. Cancer-associated HPV types were the most common in all age groups; non-cancer-associated HPV types were rare in the young and became more common linearly with age. Twenty-four types of HPV were detected; HPV 16, HPV 53, HPV 31 and HPV 18 were the most common, but none was present in more than 1.7% of subjects. The main determinant of infection with both cancer-associated and non-cancer-associated HPV types was the number of sexual partners in all age groups. Less-educated women were at an increased risk of infection with cancer-associated but not with non-cancer-associated HPV types; low socioeconomic status was associated with detection of non-cancer-associated HPV types. Among young women an increasing number of pregnancies was associated with lower HPV detection and among older women low socioeconomic status was related to increased HPV detection, particularly for the age group 35-54 years. Among women with cancer-associated HPV types, there was a higher intensity of polymerase chain reaction signal in younger than in older age groups (p < 0.001). We present additional evidence for the sexually transmitted nature of HPV infection, regardless of age group and HPV type. We confirm previous findings of a second peak of high-risk HPV infections in postmenopausal women, in this case with a clear predominance of cancer-associated HPV types. In populations with this pattern, which can be related to reactivation of latent HPV infections or high previous exposure in older women, screening with HPV testing can have a reduced specificity among older women if proper cut-off points for HPV positivity are not used. Longitudinal studies of immune responses to HPV infection in different age groups are warranted.

Epidemiology of Human Papillomavirus Infections

(1997). Epidemiology of Human Papillomavirus Infections. Hospital Practice: Vol. 32, No. 11, pp. 39-41.

New Epidemiology of Human Papillomavirus Infection and Cervical Neoplasia

New Epidemiology of Human Papillomavirus Infection and Cervical Neoplasia