Prevalence of human papillomavirus infection and phylogenetic analysis of HPV-16 E6 variants among infected women from Northern Brazil

Abstract

BackgroundThe main cause of cervical cancer in the world is high risks human papillomavirus infection (mainly represented by HPV-16 and HPV-18), that are associated to the development of malign transformation of the epithelium. HPV prevalence exhibits a wide geographical variability and HPV-16 variants have been related to an increased risk of developing cervical intraepithelial lesion. The aim of this study was to describe DNA-HPV prevalence and HPV-16 variants among a women population from Northern Brazil.MethodsOne hundred and forty three women, during routine cervical cancer screening, at Juruti Project, fulfilled an epidemiological inquiry and were screened through a molecular HPV test. HPV-16 variants were determined by sequencing the HPV-16 E6 open reading frame.ResultsForty two samples were considered HPV positive (29.4%). None of those had abnormal cytology results. HPV prevalence varied between different age groups (Z(U) = 14.62; p = <0.0001) and high-risk HPVs were more frequent among younger ages. The most prevalent type was HPV-16 (14%) and it variants were classified, predominantly, as European (87.5%).ConclusionsHPV prevalence in our population was higher than described by others and the most prevalent HPV types were high-risk HPVs. The European HPV-16 variant was the most prevalent among HPV-16 positive samples. Our study reinforces the fact that women with normal cytology and a positive molecular test for high-risk HPVs should be submitted to continuous follow up, in order to verify persistence of infection, promoting an early diagnosis of cervical cancer and/or its precursors.

Prevalence of type-specific HPV among female university students from northern Brazil

“…In Brazil, there is considerable variation in the prevalence of HPVs and the distribution of genotypes. The prevalence recorded here was much higher than that found in previous studies in southern (6.7 %) [ 17 ] and southeastern Brazil (11 %) [ 18 ], but lower than that described in a previous study in northern Brazil (29.4 %) [ 19 ]. However, all these previous studies recorded HPV-16 as the most prevalent genotype, whereas in the present study, HPV-61 and HPV-82 were the most common, although HPV-16 was the most frequent hrHPV genotype, together with HPV-59.…”

High frequency of HPV16 European variant E350G among Mexican women from Sinaloa

“…Although the identification of HPV16 variants in our study was done by assaying the E6 gene sequence, our results showed that all HPV16-positive samples were of the European variant, which was consistent with previously described results in America 23 . A study from Brazil observed that 29.4 per cent of women with normal cytology were HPV positive, with HPV16 being the most commonly observed genotype (14%), followed by HPV-52 and HPV-45 24 . In these studies, the observed HPV16 variants were classified predominantly as European (87.5%), but Asian, African and American variants were also reported 24 .…”

“…A study from Brazil observed that 29.4 per cent of women with normal cytology were HPV positive, with HPV16 being the most commonly observed genotype (14%), followed by HPV-52 and HPV-45 24 . In these studies, the observed HPV16 variants were classified predominantly as European (87.5%), but Asian, African and American variants were also reported 24 . In our study, HPV16 was also the primary viral genotype detected, followed by HPV18.…”

Frequência do Papilomavírus Humano na placenta, no colostro e no sangue do cordão umbilical

“…Isso está de acordo com os dados da literatura que mostram que esse genótipo está relacionado com a transmissão vertical 6,7 . Os outros dois genótipos encontrados (HPV-16 e HPV-18) são descritos na literatura como os mais frequentes 23,24 . Nas amostras de placenta e do sangue do cordão umbilical provenientes de uma parturiente, a determinação do genótipo não foi possível devido à sobreposição dos picos das sequências, o que indica a infecção por múltiplos genótipos 25 .…”