Epidemiology and Natural History of Human Papillomavirus Infections and Type-Specific Implications in Cervical Neoplasia
ABSTRACT Worldwide human papillomavirus (HPV) prevalence in women with normal cytology at any given point in time is approximately 10% indicating that HPV is one of the most common sexually transmitted infections. HPV-16 is consistently the most common type and HPV-18 the second with some minor regional differences. Furthermore, across the spectrum of cervical lesions, HPV-16 is consistently the most common HPV type contributing to 50-55% of invasive cervical cancer cases strongly suggesting that this viral type has a biological advantage for transmission, persistency and transformation. The same phenomenon is observed albeit at a lower level for HPV-18 and HPV-45. Sexual behavioral patterns across age groups and populations are central to the description of the HPV circulation and of the risk of infection. The concept of group sexual behavior (in addition to individual sexual behavior) is important in exploring HPV transmission and has implications for defining and monitoring HPV and cancer prevention strategies. In natural history studies, the pattern of HPV DNA prevalence by age groups is similar to the patterns of HPV incidence. Rates of exposure in young women are high and often include multiple types. There is a spontaneous and rapid decrease of the HPV DNA detection rates in the middle-age groups followed by a second rise in the post-menopausal years. This article reviews: 1) the evidence in relation to the burden of HPV infections in the world and the contributions of each HPV type to the spectrum of cervical cellular changes spanning from normal cytology to invasive cervical cancer; 2) the critical role of the patterns of sexual behavior in the populations; and 3) selected aspects of the technical and methodological complexity of natural history studies of HPV and cervical neoplasia.
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- "Moreover, HPV-33 and 31 have high prevalences in some regions (Jin et al., 2010). In the current study, HPV-16, 52, 58 and 33 were the most common types among Tibetan and Naxi women; these findings are in line with previous research (Mayineur et al., 2011, Bosch et al., 2008, Li et al., 2008). Among Han women, HPV-33 (5.1%) is the most common genotype, followed by HPV-58, 16, and 52. "
ABSTRACT: The prevalence and genotype distribution of human papillomavirus (HPV) vary throughout the world. To assess the prevalence and genotype distribution of HPV among three ethnic groups in two geographic locations in northwestern Yunnan, we recruited 522 women in Shangri-le (n=255) and Lijiang (n=267). PCR amplification of HPV DNA was performed on cervical cells from these women using two consensus primer systems (MY09/11 and GP5/6). Amplified HPV DNA was genotyped using the HPV GenoArray test. Geographically, the HPV prevalence was significantly higher (P=0.002) among Shangri-le women than among Lijiang women. Infections with high-risk (HR)-HPV and with multiple HPV genotypes were also significantly more common (P=0.001) among women in Shangri-le than women in Lijiang. Additionally, the prevalence of overall, HR-HPV, and single genotype HPV infections was significantly higher (P=0.001) among Tibetan women than among Naxi and Han women. HPV-16 and HPV-33 were significantly more frequent in Shangri-le women compared with Lijiang (P=0.006) women. In addition, HPV-16 (9.81%) and HPV-33 (5.88%) were significantly more prevalent in Tibetan women than in Naxi and Han women. Here, for the first time, we highlight the significant variation in the prevalence and genotype distribution of HPV in various populations in the north-western region of Yunnan Province. This article is protected by copyright. All rights reserved.Journal of Medical Virology 08/2015; DOI:10.1002/jmv.24352 · 2.22 Impact Factor
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- "However, there remain around 500,000 new cases of cervical cancer each year worldwide, which results in about 274,000 deaths (Parkin et al., 2005). HPV-16 is present in around 50% of all cervical cancers (Bosch et al., 2008), and it is by far the most prevalent high-risk mucosal HPV. Consequently, the development of prophylactic vaccines to reduce HPV infections has mainly focused on this HPV genotype. "
ABSTRACT: Human papilloma virus (HPV)-16 is the prevalent genotype associated with cervical tumours. Virus-like-particle-based vaccines have proven to be effective in limiting new infections of high-risk HPVs, but their high cost has hampered their use, especially in the poor developing countries. Avipox-based recombinants are replication-restricted to avian species and represent efficient and safe vectors also for immunocompromised hosts, as they can elicit a complete immune response. A new fowlpox virus recombinant encoding HPV-L1 (FPL1) was engineered and evaluated side-by-side with a FP recombinant co-expressing L1 and green fluorescent protein (FPL1GFP) for correct expression of L1 in vitro in different cell lines, as confirmed by Western blotting, immunofluorescence, real-time PCR, and electron microscopy. Mice were also immunised to determine its immunogenicity. Here, we demonstrate that the FPL1 recombinant better expresses L1 in the absence of GFP, correctly assembles structured capsomers into virus-like particles (VLPs), and elicits an immune response in a preclinical animal model. To our knowledge, this is the first report of HPV VLPs assembled in eukaryotic cells using an avipox recombinant. Copyright © 2015. Published by Elsevier B.V.Antiviral Research 02/2015; 116. DOI:10.1016/j.antiviral.2015.01.012 · 3.94 Impact Factor
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- "Human Papillomavirus (HPV) and Chlamydia trachomatis are considered among the most common sexually transmitted infections worldwide [Bosch et al., 2012; Forman et al., 2012; Ferná ndez-Benítez et al., 2013; Gottlieb et al., 2013]. A persistent infection with an oncogenic high risk- HPV type is recognized as a crucial event for cervical cancer development [Bosch et al., 2008]. Although only a small number of females infected with HPV develop cervical cancer, cervical precursor lesions designed as squamous intraepithelial lesions are frequently diagnosed, a process influenced highly by the HPV genotype and by other factors. "
ABSTRACT: Chlamydia trachomatis causing chronic inflammatory diseases has investigated as possible human papillomavirus (HPV) cofactor in cervical cancer. The aim of this study is to evaluate the prevalence of Chlamydia trachomatis and HPV co-infection in different cohorts of asymptomatic women from a Northern Italy area at high incidence for cervical cancer. Cervical samples from 441 females were collected from Cervical Cancer Screening Program, Sexually Transmitted Infectious and Assisted Reproductive Technology centres. HPV and Chlamydia trachomatis were detected simultaneously and genotyped using a highly sensitive bead based assay. The overall prevalence of Chlamydia trachomatis was estimated 9.7%, in contrast with the reported national data of 2.3%, and co-infection with HPV was diagnosed in the 17% of the samples. In females ≤ 25 years of age, the infection reached a peak of 22% and co-infection with HPV of 45.8% (P < 0.001). Of note, in young females diagnosed with low grade cervical lesions, no significant difference between Chlamydia trachomatis and HPV distribution was observed, while differently, HPV co-infection was found significantly associated to the presence of intraepithelial lesions when compared to older females (20% vs. 1%; P < 0.001). In this study, the use of a high sensitive molecular technique exhibited higher analytical sensitivity than the referred assays for the diagnosis of Chlamydia trachomatis and HPV co-infection in asymptomatic females, leading to reduction of the potential to identify incorrectly the infection status. An active screening for timely treatment of Chlamydia trachomatis infection is suggested in young females to evaluate a possible decrease in incidence of pre-cancer intraepithelial lesions. J. Med. Virol. © 2014 Wiley Periodicals, Inc.Journal of Medical Virology 08/2014; 86(11). DOI:10.1002/jmv.24041 · 2.22 Impact Factor