Distribution of 37 mucosotropic HPV types in women with cytologically normal cervical smears: The age‐related patterns for high‐risk and low‐risk types

Abstract

Before guidelines can be set for the use of high-risk human papillomavirus (HR HPV) testing in cervical cancer screening and vaccine preparation, age-related prevalence of HR HPV types in cytologically normal smears has to be known. Therefore, in a cross-sectional study the prevalence of 37 different HPV genotypes and putatively unidentified HPV types was determined in 3,305 cytologically normal cervical smears from the general female population (15-69 years of age) using an HPV general primer GP5+/bioGP6+ mediated PCR assay. Subsequently, HPV-positive cervical smears were typed for 19 HR and 18 low-risk (LR) HPVs with an enzyme immunoassay using HPV type-specific oligoprobes in cocktails and individually, respectively. Overall, -HR and -LR HPV prevalences appeared to be of 4.6%, 3.3%, and 1.0%, respectively. Twenty-six different HPV types were detected in the 152 HPV-positive samples, the most prevalent types being HPV 16, 31, and 18. With regard to age, a peak prevalence of 19.6% for all HPVs was found in women 25-29 years of age, which declined to a mean of 4.3% in women over 30 years. With regard cytologically normal cervical smears (n = 3, 011) of women participating in the population-based screening program in the Netherlands (30 to 60 years), all HR HPVs showed decreased occurrence with increasing age, whereas the prevalence of LR HPV types remained constant. We suggest that screening for abnormal cytology implies screening for HR HPV infections and the subsequent treatment results in a decline of HR HPV prevalence in contrast to LR HPV prevalence during the years of screening.

Prevalence of human papillomavirus infection in women in Turin, Italy

“…The frequency of multiple infections was lower than in other populations [6], especially Latin American ones in whom HPV infection is substantially more frequent [5,11]. In our study, half of the infections were due to types 16, 66, 45 and 31, in decreasing order.…”

“…The frequency of HPV 16 was high (32.6% of HPV-positive women), while type 18 was almost absent. Low-risk types were rare, but, as observed in other areas [5,6,12], they represented a larger proportion of infections in middle-aged women than in young women.…”

“…Infection with any of six high-risk HPV types (HPV 16, 18, 31, 33, 52 and 58) was found in 5.1% of 332 archival smears from women without CIN II, or more severe lesions [24]. The overall prevalence of HPV DNA among 3305 cytologically-negative women aged 15-70 years who participated in cervical screening in The Netherlands was 4.6%, and the rate peaked at 20% at age 25-29 years [6]. The incidence of invasive cervical cancer in that country in 1993-1997 (world-standardised rate 6.6/ 100 000) [25] was also similar to that in Turin (6.8/ 100 000).The rate of detection of HPV DNA in a random population sample of 1000 women aged 20-29 years with normal cytological appearance in Copenhagen, Denmark, was 15% [26], which is similar to the prevalence of 13% that we found in Turin among women aged 25-29 years.…”

“…PCR positivity was assessed by hybridisation of PCR products in an enzyme immunoassay (EIA) using two HPV oligoprobe cocktails that together contain the following 36 HPV types: 6 [6,19]. The sensitivity and specificity of EIA detection were determined previously using dilution lines of cloned HPVs or cervical smears in which these types were identified in earlier studies [6,20].…”

“…Few such studies have been conducted [5][6][7][8][9][10][11][12][13], particularly in Southern Europe [14,15], and no large population-based survey of the prevalence of type-specific HPV is available for Italy.…”