939 resultados para genital human papillomavirus


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Background: A strong association between persistent infection with oncogenic types of human papillomavirus (HPV) and cervical cancer is well established. Small numbers of international studies examining adolescent HPV infection and the risk factors associated are published, but there is currently no evidence on the prevalence and risk factors for HPV in an Australian, sexually active female adolescent population. Methods: To provide prevalence and risk factors for HPV in a female sexually active, senior high school population in the Australian Capital Territory (ACT), a convenience sample of 161, 16–19-year-old females attending a senior high school was evaluated. The sample formed part of a larger sample recruited for a study of sexually transmitted infections and blood-borne viruses in senior high school students. A clinical record was used to collect information about sexual and other risk behaviours, while self-collected vaginal swabs were tested for HPV DNA detection and genotyping using polymerase chain reaction. Results: The prevalence of HPV DNA in this sample overall was 11.2%, with multiple genotypes in 38%. No statistically significant associations were found between HPV DNA and the number of male partners, age of coitarche, time since first sexually active, condom use, smoking or alcohol intake. Conclusions: This is the first Australian study that has examined the prevalence and risk factors for genital HPV in this demographic group. The prevalence of HPV infection is slightly lower than reported in similar age groups overseas and is lower than other Australian studies in older women and those attending sexual health centres. Of HPV-positive young women, high-risk genotypes were found in over half, with more than one-third of HPV existing as multiple genotypes. Large community-based prevalence studies are needed to guide the development of recommendations for the vaccination of young women against HPV and to support other health promotion initiatives.

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Background: With over 440 million cases of infections worldwide, genital HPV is the most frequent sexually transmitted infection. There are several types including high risk types 16, 18, 58 and 70 among others, which are known to cause cervical cell abnormality and if persistent, can lead to cervical cancer which globally, claims 288,000 lives annually. 33.4 million people worldwide are currently living with HIV/AIDS, with 22.4 million in sub-Saharan Africa where 70% of the female population living with HIV/AIDS is also found. Similar risk factors for HPV, cervical cancer and HIV/AIDS include early age at sexual debut, multiple sexual partners, infrequent condom use, history of STI and immune-suppression. ^ Objectives: To describe the role of HPV in cervical cancer development, to describe the influence of HIV/AIDS on HPV and in the development of cervical cancer and to describe the importance of preventive measures such as screening. ^ Methods: This is a literature review where data were analyzed qualitatively and a descriptive narrative style used to evaluate and present the information. The data came from searches using Pub Med, Cochrane Library, EBSCO Medline databases as well as websites such as the CDC and WHO. Articles selected were published in English over the last 10 years. Keywords used included: 'HPV, cervical cancer and HIV', 'HIV and HPV', 'HPV and cervical cancer', 'HPV infection', 'HPV vaccine', 'genital HPV', 'HIV and cervical cancer', 'prevalence of HIV and cervical cancer' and 'prevalence of cervical cancer'. ^ Results: Women with HIV/AIDS have multiple HPV types, persistent infection, are more likely to present with cervical neoplasia and are at higher risk for cervical cancer. Research also shows that HIV could affect the transmissibility of HPV and that HPV itself could also increase the susceptibility to HIV acquisition. ^ Conclusion: HIV, genital HPV and cervical cancer are all preventable. Need to emphasize programs that aim to increase HIV/AIDS, HPV and cervical cancer awareness. Stress importance of behavior modification such as frequent use of condoms, decreased sexual partners and delayed first intercourse. Facilitate programs for screening and treating HPV, male circumcision, effective management of HAART and HPV vaccination.^

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The purpose of this study was to investigate women's knowledge and attitudes regarding genital human papillomavirus (n=100). Using a descriptive design, the Health Education Questionnaire was administered to 100 female patients (Mean Age = 33, SD = 7.17) at a physicians office in South Florida. The results indicated a lack of knowledge regarding genital human papillomavirus with 21 patients (21%) reported having knowledge and 79 (79%) having never heard of this disease. In addition, the group familiar with genital human papillomavirus also possessed a low level of knowledge with only 57% acknowledging an association of genital human papillomavirus and cervical cancer, 52% aware that a pap smear can detect the virus, 42% knowing that antibiotics can not treat the disease and 57% aware that it is not associated with a family history. An association was found between attitudes and health seeking behaviors. Subjects stating that they would take all measures to prevent genital human papillomavirus, were more likely to have a pap smear within the last year (Chi-square (1) = 4.33, p < .05). Higher levels of education and income were associated with increased knowledge regarding genital human papillomavirus when subjects were categorized according to sociodemographic characteristic (Chi-square (1) =9.45, p < .05; Chi-square (1) = 6.75, p < .05). There was no significant correlation between knowledge and ethnicity, marital status or age. Findings indicated the need for improved education and promotion of positive attitudes regarding human papillomaviurs in order to improve health seeking behaviors among women.

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Background Human papillomavirus (HPV) is the aetiological agent for cervical cancer and genital warts. Concurrent HPV and HIV infection in the South African population is high. HIV positive (+) women are often infected with multiple, rare and undetermined HPV types. Data on HPV incidence and genotype distribution are based on commercial HPV detection kits, but these kits may not detect all HPV types in HIV + women. The objectives of this study were to (i) identify the HPV types not detected by commercial genotyping kits present in a cervical specimen from an HIV positive South African woman using next generation sequencing, and (ii) determine if these types were prevalent in a cohort of HIV-infected South African women. Methods Total DNA was isolated from 109 cervical specimens from South African HIV + women. A specimen within this cohort representing a complex multiple HPV infection, with 12 HPV genotypes detected by the Roche Linear Array HPV genotyping (LA) kit, was selected for next generation sequencing analysis. All HPV types present in this cervical specimen were identified by Illumina sequencing of the extracted DNA following rolling circle amplification. The prevalence of the HPV types identified by sequencing, but not included in the Roche LA, was then determined in the 109 HIV positive South African women by type-specific PCR. Results Illumina sequencing identified a total of 16 HPV genotypes in the selected specimen, with four genotypes (HPV-30, 74, 86 and 90) not included in the commercial kit. The prevalence's of HPV-30, 74, 86 and 90 in 109 HIV positive South African women were found to be 14.6 %, 12.8 %, 4.6 % and 8.3 % respectively. Conclusions Our results indicate that there are HPV types, with substantial prevalence, in HIV positive women not being detected in molecular epidemiology studies using commercial kits. The significance of these types in relation to cervical disease remains to be investigated.

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As cervical cancer is causally associated with 14 high-risk types of human papillomavirus (HPV), a successful HPV vaccine will have a major impact on this disease. Although some persistent HPV infections progress to cervical cancer, host immunity is generally able to clear most HPV infections. Both cell-mediated and antibody responses have been implicated in influencing the susceptibility, persistence or clearance of genital HPV infection. There have been two clinical trials that show that vaccines based on virus-like particles (VLPs) made from the major capsid protein, L1, are able to type specifically protect against cervical intra-epithelial neoplasia and infection. However, there is no evidence that even a mixed VLP vaccine will protect against types not included in the vaccine, and a major challenge that remains is how to engineer protection across a broader spectrum of viruses. Strategies for production of HPV vaccines using different vaccine vectors and different production systems are also reviewed. © 2005 Elsevier Ltd. All rights reserved.

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Recombinant human papillomavirus (HPV) virus-like particles (VLPs) made from the major capsid protein L1 are promising vaccine candidates for use as vaccines against genital and other HPV infections, and particularly against HPV-16. However, HPV-16 genotype variants have different binding affinities for neutralising mouse Mabs raised against HPV-16 L1 VLPs. This paper analyses, using a panel of well-characterised Mabs, the effects on the antigenicity of various C- and N-terminal deletants of HPV-16 L1 made in insect cells via recombinant baculovirus, of an A → T mutation at residue 266 (A266T), and of a C → G mutation at conserved position 428 (C428G). The effects of these changes on assembly of the variant L1s were studied by electron microscopy. Binding of Mab H16:E70 to A266T was reduced by almost half in comparison to wild type L1. Retention of the C-terminal region 428-483 was critical for the binding of conformation-specific Mabs (H16:V5, H16:E70, H16:U4 and H16:9A) whereas deletion of the nuclear localisation signal (NLS) or the C428G mutation or an N-terminal deletion (residues 2-9) did not affect the antigenicity. The N-terminal deletion resulted in a mixed population of 30 and 55 nm VLPs, which differs from the same construct expressed in Escherichia coli, whereas pentamer aggregates resulted from deletion of the 428-465 region or the C428G mutation. The results have implications both for considering use of single-genotype HPV vaccines, and for design of novel second-generation vaccines. © 2006 Elsevier B.V. All rights reserved.

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Most women acquire genital high risk human papillomavirus (HPV) infection during their lifetime, but seldom the infection persists and leads to cervical cancer. However, currently it is not possible to identify the women who will develop HPV mediated cervical cancer and this often results to large scale follow-up and overtreatment of the likely spontaneously regressing infection. Thus, it is important to obtain more information on the course of HPV and find markers that could help to identify HPV infected women in risk for progression of cervical lesions and ultimately cancer. Nitric oxide is a free radical gas that takes part both in immune responses and carcinogenesis. Nitric oxide is produced also by cervical cells and therefore, it is possible that cervical nitric oxide could affect also HPV infection. In the present study, including 801 women from the University of Helsinki between years of 2006 and 2011, association between HPV and cervical nitric oxide was evaluated. The levels of nitric oxide were measured as its metabolites nitrate and nitirite (NOx) by spectrophotometry and the expression of nitric oxide producing enzymes endothelial and inducible synthases (eNOS, iNOS) by Western blotting. Women infected with HPV had two-times higher cervical fluid NOx levels compared with non-infected ones. The expression levels of both eNOS and iNOS were higher in HPV-infected women compared with non-infected. Another sexually transmitted disease Chlamydia trachomatis that is an independent risk factor for cervical cancer was also accompanied with elevated NOx levels, whereas vaginal infections, bacterial vaginosis and candida, did not have any effect on NOx levels. The meaning of the elevated HPV related cervical nitric oxide was evaluated in a 12 months follow-up study. It was revealed that high baseline cervical fluid NOx levels favored HPV persistence with OR 4.1. However, low sensitivity (33%) and high false negative rate (67%) restrict the clinical use of the current NOx test. This study indicated that nitric oxide favors HPV persistence and thus it seems to be one of the cofactor associated with a risk of carcinogenesis.

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Background: Two clinically relevant high-risk HPV (HR-HPV) types 16 and 18 are etiologically associated with the development of cervical carcinoma and are also reported to be present in many other carcinomas in extra-genital organ sites. Presence of HPV has been reported in breast carcinoma which is the second most common cancer in India and is showing a fast rising trend in urban population. The two early genes E6 and E7 of HPV type 16 have been shown to immortalize breast epithelial cells in vitro, but the role of HPV infection in breast carcinogenesis is highly controversial. Present study has therefore been undertaken to analyze the prevalence of HPV infection in both breast cancer tissues and blood samples from a large number of Indian women with breast cancer from different geographic regions. Methods: The presence of all mucosal HPVs and the most common high-risk HPV types 16 and 18 DNA was detected by two different PCR methods - (i) conventional PCR assays using consensus primers (MY09/11, or GP5 +/GP6+) or HPV16 E6/E7 primers and (ii) highly sensitive Real-Time PCR. A total of 228 biopsies and corresponding 142 blood samples collected prospectively from 252 patients from four different regions of India with significant socio-cultural, ethnic and demographic variations were tested. Results: All biopsies and blood samples of breast cancer patients tested by PCR methods did not show positivity for HPV DNA sequences in conventional PCRs either by MY09/11 or by GP5+/GP6+/HPV16 E6/E7 primers. Further testing of these samples by real time PCR also failed to detect HPV DNA sequences. Conclusions: Lack of detection of HPV DNA either in the tumor or in the blood DNA of breast cancer patients by both conventional and real time PCR does not support a role of genital HPV in the pathogenesis of breast cancer in Indian women.

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Background: Human papillomavirus (HPV), the causal agent of cervical cancer, appears to be involved in the etiology of cancer of the oral cavity and oropharynx. To investigate these associations, we conducted a multicenter case-control study of cancer of the oral cavity and oropharynx in nine countries. Methods: We recruited 1670 case patients (1415 with cancer of the oral cavity and 255 with cancer of the oropharynx) and 1732 control subjects and obtained an interview, oral exfoliated cells, and blood from all participants and fresh biopsy specimens from case patients. HPV DNA was detected by polymerase chain reaction (PCR). Antibodies against HPV16 L1, E6, and E7 proteins in plasma were detected with enzyme-linked immunosorbent assays. Multivariable models were used for case-control and case-case comparisons. Results: HPV DNA was detected in biopsy specimens of 3.9% (95% confidence interval [CI]=2.5% to 5.3%) of 766 cancers of the oral cavity with valid PCR results and 18.3% (95% CI=12.0% to 24.7%) of 142 cancers of the oropharynx (oropharynx and tonsil combined) with valid PCR results. HPV DNA in cancer biopsy specimens was detected less frequently among tobacco smokers and paan chewers and more frequently among subjects who reported more than one sexual partner or who practiced oral sex. HPV16 DNA was found in 94.7% of HPV DNA-positive case patients. HPV DNA in exfoliated cells was not associated with cancer risk or with HPV DNA detection in biopsy specimens. Antibodies against HPV16 L1 were associated with risk for cancers of the oral cavity (odds ratio [OR]=1.5, 95% CI=1.1 to 2.1) and the oropharynx (OR=3.5, 95% CI=2.1 to 5.9). Antibodies against HPV16 E6 or E7 were also associated with risk for cancers of the oral cavity (OR=2.9, 95% CI=1.7 to 4.8) and the oropharynx (OR=9.2, 95% CI=4.8 to 17.7). Conclusions: HPV appears to play an etiologic role in many cancers of the oropharynx and possibly a small subgroup of cancers of the oral cavity. The most common HPV type in genital cancers (HPV16) was also the most common in these tumors. The mechanism of transmission of HPV to the oral cavity warrants further investigation.

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Tese de doutoramento, Biologia (Microbiologia), Universidade de Lisboa, Faculdade de Ciências, 2014

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To specifically induce a mucosal antibody response to purified human papillomavirus type 16 (HPV16) virus-like particles (VLP), we immunized female BALB/c mice orally, intranasally, and/or parenterally and evaluated cholera toxin (CT) as a mucosal adjuvant. Anti-HPV16 VLP immunoglobulin G (IgG) and IgA titers in serum, saliva, and genital secretions were measured by enzyme-linked immunosorbent assay (ELISA). Systemic immunizations alone induced HPV16 VLP-specific IgG in serum and, to a lesser extent, in genital secretions but no secretory IgA. Oral immunization, even in the presence of CT, was inefficient. However, three nasal immunizations with 5 microgram of VLP given at weekly intervals to anesthetized mice induced high (>10(4)) and long-lasting (>15 weeks) titers of anti-HPV16 VLP antibodies in all samples, including IgA and IgG in saliva and genital secretions. CT enhanced the VLP-specific antibody response 10-fold in serum and to a lesser extent in saliva and genital secretions. Nasal immunization of conscious mice compared to anesthetized mice was inefficient and correlated with the absence of uptake of a marker into the lung. However, a 1-microgram VLP systemic priming followed by two 5-microgram VLP intranasal boosts in conscious mice induced both HPV16 VLP-specific IgG and IgA in secretions, although the titers were lower than in anesthetized mice given three intranasal immunizations. Antibodies in serum, saliva, and genital secretions of immunized mice were strongly neutralizing in vitro (50% neutralization with ELISA titers of 65 to 125). The mucosal and systemic/mucosal HPV16 VLP immunization protocols that induced significant titers of neutralizing IgG and secretory IgA in mucosal secretions in mice may be relevant to genital HPV VLP-based human vaccine trials.

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Objectives To determine the effect of human papillomavirus (HPV) quadrivalent vaccine on the risk of developing subsequent disease after an excisional procedure for cervical intraepithelial neoplasia or diagnosis of genital warts, vulvar intraepithelial neoplasia, or vaginal intraepithelial neoplasia. Design Retrospective analysis of data from two international, double blind, placebo controlled, randomised efficacy trials of quadrivalent HPV vaccine (protocol 013 (FUTURE I) and protocol 015 (FUTURE II)). Setting Primary care centres and university or hospital associated health centres in 24 countries and territories around the world. Participants Among 17 622 women aged 15–26 years who underwent 1:1 randomisation to vaccine or placebo, 2054 received cervical surgery or were diagnosed with genital warts, vulvar intraepithelial neoplasia, or vaginal intraepithelial neoplasia. Intervention Three doses of quadrivalent HPV vaccine or placebo at day 1, month 2, and month 6. Main outcome measures Incidence of HPV related disease from 60 days after treatment or diagnosis, expressed as the number of women with an end point per 100 person years at risk. Results A total of 587 vaccine and 763 placebo recipients underwent cervical surgery. The incidence of any subsequent HPV related disease was 6.6 and 12.2 in vaccine and placebo recipients respectively (46.2% reduction (95% confidence interval 22.5% to 63.2%) with vaccination). Vaccination was associated with a significant reduction in risk of any subsequent high grade disease of the cervix by 64.9% (20.1% to 86.3%). A total of 229 vaccine recipients and 475 placebo recipients were diagnosed with genital warts, vulvar intraepithelial neoplasia, or vaginal intraepithelial neoplasia, and the incidence of any subsequent HPV related disease was 20.1 and 31.0 in vaccine and placebo recipients respectively (35.2% reduction (13.8% to 51.8%)). Conclusions Previous vaccination with quadrivalent HPV vaccine among women who had surgical treatment for HPV related disease significantly reduced the incidence of subsequent HPV related disease, including high grade disease.

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Objectives: Human papillomavirus (HPV) infection is a major risk factor for cervical disease. Using baseline data from the HIV-infected cohort of Evandro Chagas Clinical Research Institute at Fiocruz, Rio de Janeiro, Brazil, factors associated with an increased prevalence of HPV were assessed. Methods: Samples from 634 HIV-infected women were tested for the presence of HPV infection using hybrid capture 11 and polymerase chain reaction. Prevalence ratios (PR) were estimated using Poisson regression analysis with robust variance. Results: The overall prevalence of HPV infection was 48%, of which 94% were infected with a high-risk HPV. In multivariate analysis, factors independently associated with infection with high-risk HPV type were: younger age (<30 years of age; PR 1.5, 95% confidence interval (CI) 1.1-2.1), current or prior drug use (PR 1.3, 95% CI 1.0-1.6), self-reported history of HPV infection (PR 1.2, 95% CI 0.96-1.6), condom use in the last sexual intercourse (PR 1.3, 95% CI 1.1-1.7), and nadir CD4+ T-cell count <100 cells/mm(3) (PR 1.6, 95% CI 1.2-2.1). Conclusions: The estimated prevalence of high-risk HPV-infection among HIV-infected women from Rio de Janeiro, Brazil, was high. Close monitoring of HPV-related effects is warranted in all HIV-infected women, in particular those of younger age and advanced immunosuppression. (C) 2008 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

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Background: Human papillomavirus (HPV) knowledge has rarely been investigated in the context of a national vaccination program. The present study investigated HPV knowledge after the introduction of a national HPV vaccination program in Australia using a national sample of men and women. Methods: Questions assessing HPV knowledge were part of a broader national study of health and relationships administered via a computer-assisted telephone interview. These findings are from wave four of the study, conducted between 2007 and 2008. Knowledge questions about HPV included its association with cervical cancer, genital warts and abnormal Pap tests. Results: A total of 2634 women and 2556 men between the ages of 18 and 70 were interviewed. Overall, 62.8% (95% confidence interval (CI): 60.8–64.7%) of women and 38.3% (95% CI: 36.3–40.4%) of men had heard of HPV. Of these, 66.0% (95% CI: 64.1–67.9%) correctly answered that HPV is associated with cervical cancer, 50.2% (95% CI: 48.2–52.1%) answered that HPV is associated with abnormal Pap tests and 44.5% (95% CI:42.5–46.5%) answered that HPV causes warts. Predictors of good knowledge included being female, aged between 26 and 45, holding higher education levels and older age at first sex. Ever having a Pap test was also associated with awareness about HPV. Conclusion: One of the highest levels of knowledge about HPV in Australia to date is reported in the present study. Knowledge about the association between HPV and cervical cancer was particularly high, especially when compared with knowledge of the association with genital warts. This appears to be a consequence of the marketing of the HPV vaccine as a vaccination against cervical cancer.

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BACKGROUND: The National Human Papillomavirus (HPV) Vaccination Program in Australia commenced in 2007 for females and in 2013 for males, using the quadrivalent HPV vaccine (HPV 6,11,16,18). Thus far, we have demonstrated very substantial reductions in genital warts and in the prevalence of HPV among young Australian women, providing early evidence for the success of this public health initiative. Australia has a long history of school-based vaccination programs for adolescents, with comparatively high coverage. However, it is not clear what factors promote success in a school vaccination program. The HPV.edu study aims to examine: 1) student knowledge about HPV vaccination; 2) psycho-social outcomes and 3) vaccination uptake.

METHODS/DESIGN: HPV.edu is a cluster randomised trial of a complex intervention in schools aiming to recruit 40 schools with year-8 enrolments above 100 students (approximately 4400 students). The schools will be stratified by Government, Catholic, and Independent sectors and geographical location, with up to 20 schools recruited in each of two states, Western Australia (WA) and South Australia (SA), and randomly allocated to intervention or control (usual practice). Intervention schools will receive the complex intervention which includes an adolescent intervention (education and distraction); a decisional support tool for parents and adolescents and logistical strategies (consent form returns strategies, in-school mop-up vaccination and vaccination-day guidelines). Careful process evaluation including an embedded qualitative evaluation will be undertaken to explore in depth possible mechanisms for any observed effect of the intervention on primary and secondary outcomes.

DISCUSSION: This study is the first to evaluate the relative effectiveness of various strategies to promote best practice in school-based vaccination against HPV. The study aims to improve vaccination-related psychosocial outcomes, including adolescent knowledge and attitudes, decision-making involvement, self-efficacy, and to reduce fear and anxiety. The study also aims to improve school vaccination program logistics including reduction in time spent vaccinating adolescents and increased number of consent forms returned (regardless of decision). Less anxiety in adolescents will likely promote more efficient vaccination, which will be more acceptable to teachers, nurses and parents. Through these interventions, it is hoped that vaccination uptake will be increased.