Sexual Behavior Patterns and Condom Use in Newly Sexually Active Female University Students.

Our objective was to describe sexual behavior patterns and condom use in newly sexually active female university students. We conducted a 4-year retrospective cohort study (2000-2007) of university women enrolled close to sexual debut (N = 250). Participants reported daily information on intercourse, condom use, and partner/partnership characteristics into Web-based biweekly sexual behavior diaries. We calculated intercourse frequency, proportion of condom-protected events, and incidence of new partner acquisition. We used logistic regression to examine factors associated with condom use at sexual debut; Kaplan-Meier methods to describe cumulative incidence of condom non-use after use at debut; and Cox proportional hazards ratios to examine factors associated with condom non-use. A total of 188 women had at least one male sex partner prior to enrollment or during follow-up. One-third (34.1%) of 27,736 intercourse events were condom-protected. Older age (20+ vs. < 20 years) and use of hormonal birth control were associated with lower likelihood of condom use at sexual debut (adjusted odds ratio [aOR] 0.41, 95% CI 0.17-0.97 and aOR 0.32, 95% CI 0.10-1.03, respectively). Women who reported partners with previous sex partners were less likely to discontinue using condoms after debut (hazard ratio = 0.35, 0.16-0.77) than those reporting partners without previous partners. In college-aged women, older age and hormonal contraceptive use were each inversely associated with condom use at first intercourse. Women with sexually experienced partners were more likely to continue using condoms. Continued efforts are necessary to promote condom use among college-aged women.

Type-dependent association between risk of cervical intraepithelial neoplasia and viral load of oncogenic human papillomavirus types other than types 16 and 18.

Studies of the clinical relevance of human papillomavirus (HPV) DNA load have focused mainly on HPV16 and HPV18. Data on other oncogenic types are rare. Study subjects were women enrolled in the atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL) triage study who had ≥1 of 11 non-HPV16/18 oncogenic types detected during a 2-year follow-up at 6-month intervals. Viral load measurements were performed on the first type-specific HPV-positive specimens. The association of cervical intraepithelial neoplasia grades 2-3 (CIN2/3) with type-specific HPV DNA load was assessed with discrete-time Cox regression. Overall, the increase in the cumulative risk of CIN2/3 per 1 unit increase in log10 -transformed viral load was statistically significant for four types within species 9 including HPV31 (adjusted hazard ratio [HR adjusted ] = 1.32: 95% confidence interval [CI], 1.14-1.52), HPV35 (HR adjusted = 1.47; 95% CI, 1.23-1.76), HPV52 (HR adjusted = 1.14; 95% CI, 1.01-1.30) and HPV58 (HR adjusted = 1.49; 95% CI, 1.23-1.82). The association was marginally significant for HPV33 (species 9) and HPV45 (species 7) and was not appreciable for other types. The per 1 log10 -unit increase in viral load of a group of species 9 non-HPV16 oncogenic types was statistically significantly associated with risk of CIN2/3 for women with a cytologic diagnosis of within normal limits, ASC-US, or LSIL at the first HPV-positive visit but not for those with high-grade SIL. Findings suggest that the viral load-associated risk of CIN2/3 is type-dependent, and mainly restricted to the species of HPV types related to HPV16, which shares this association.

Incident Detection of High-Risk Human Papillomavirus Infections in a Cohort of High-Risk Women Aged 25-65 Years.

BACKGROUND: The risk of incident high-risk human papillomavirus (HR-HPV) infection associated with recent sexual behaviors is undefined in mid-adult women (defined as women aged 25-65 years). METHODS: Triannually, 420 female online daters aged 25-65 years submitted vaginal specimens for HPV testing and completed health and sexual behavior questionnaires. The cumulative incidence of and risk factors for incident HR-HPV detection were estimated by Kaplan-Meier and Cox proportional hazards methods. RESULTS: The 12-month cumulative incidence of HR-HPV detection was 25.4% (95% confidence interval [CI], 21.3%-30.1%). Current hormonal contraceptive use was positively associated with incident HR-HPV detection. Lifetime number of male sex partners was also positively associated but only among women not recently sexually active with male partners. In analysis that adjusted for hormonal contraceptive use and marital status, women reporting multiple male partners or male partners who were new, casual, or had ≥1 concurrent partnership had a hazard of incident HR-HPV detection that was 2.81 times (95% CI, 1.38-5.69 times) that for women who reported no male sex partners in the past 6 months. Thus, among women with multiple male partners or male partners who were new, casual, or had ≥1 concurrent partnership, approximately 64% of incident HR-HPV infections were attributable to one of those partners. CONCLUSIONS: Among high-risk mid-adult women with recent new male partners, multiple male partners, or male partners who were casual or had ≥1 concurrent partnership, about two thirds of incident HR-HPV detections are likely new acquisitions, whereas about one third of cases are likely redetections of prior infections.

Variant-specific persistence of infections with human papillomavirus Types 31, 33, 45, 56 and 58 and risk of cervical intraepithelial neoplasia.

In our previous study of the etiologic role of oncogenic human papillomavirus (HPV) types other than HPV16 and 18, we observed a significantly higher risk of cervical intraepithelial neoplasia Grades 2-3 (CIN2/3) associated with certain lineages of HPV types 31/33/45/56/58 [called high-risk (HR) variants] compared with non-HR variants. This study was to examine whether these intra-type variants differ in persistence of the infection and persistence-associated risk of CIN2/3. Study subjects were women who had any of HPV types 31/33/45/56/58 newly detected during a 2-year follow-up with 6-month intervals. For each type, the first positive sample was used for variant characterization. The association of reverting-to-negativity with group of the variants and CIN2/3 with length of positivity was assessed using discrete Cox regression and logistic regression, respectively. Of the 598 newly detected, type-specific HPV infections, 312 became undetectable during follow-up. Infections with HR, compared with non-HR, variants were marginally more likely to become negative [adjusted hazard ratio = 1.3; 95% confidence interval (CI), 0.9-1.8]. The adjusted odds ratio associating with the development of CIN2/3 was 3.0 (95% CI, 1.2-7.4) for persistent infections with HR variants for 6 months and 10.0 (95% CI, 3.8-38.0) for persistent infections with HR variants for 12-18 months as compared with the first positive detection of HR variants. Among women with non-HR variants, there were no appreciable differences in risk of CIN2/3 by length of positivity. Findings suggest that the lineage-associated risk of CIN2/3 was not mediated through a prolonged persistent infection, but oncogenic heterogeneity of the variants.

Re-detection vs. new acquisition of high-risk human papillomavirus in mid-adult women.

To understand high-risk (hr) human papillomavirus (HPV) epidemiology in mid-adulthood, we assessed whether associations between incident detection of hrHPV DNA and recent sexual behavior differed according to whether or not there was serologic evidence of prior infection. From 2011 to 2012, we enrolled 409 women aged 30-50 years into a 6-month longitudinal study. We collected health and sexual behavior histories, enrollment sera for HPV antibody testing, and monthly self-collected vaginal swabs for HPV DNA genotyping. Generalized estimating equations logistic regression identified risk factors for type-specific incident hrHPV DNA, stratified by type-specific hrHPV serostatus at enrollment. Population attributable risks of hrHPV due to prior and recent exposure were estimated. When type-specific hrHPV serology was negative, recent sexual risk behavior was positively associated with incident hrHPV DNA (odds ratio in women reporting ≥3 recent sexual risk behaviors [e.g., new or multiple partners] vs. no recent sexual activity = 9.8, 95% CI: 2.4-40.6). No associations with recent sexual behavior were observed with positive type-specific hrHPV serology. Thirty percent of incident hrHPV DNA detection was attributable to prior infection (with positive serology) and 40% was attributable to recent sexual risk behavior (with negative serology). The proportion of incident hrHPV DNA detection attributable to recent sexual risk behavior decreased with increasing age. Among women with serologic evidence of prior infection, re-detection of the same hrHPV type is likely due to reactivation or intermittent detection of persistent infection. Without serologic evidence of prior infection, new detection is likely due to new acquisition or to intermittent detection of persisting infection.

Determinants of High-Risk Human Papillomavirus Seroprevalence and DNA Prevalence in Mid-Adult Women.

BACKGROUND: The epidemiology of high-risk human papillomavirus (hrHPV) infections in mid-adult women is not well understood. METHODS: We conducted a cross-sectional analysis of 379 women 30 to 50 years of age. Vaginal samples were tested for type-specific HPV DNA by polymerase chain reaction. Sera were tested for type-specific HPV antibodies by Luminex-based assay. Assays included 13 hrHPV types (16/18/31/33/35/39/45/51/52/56/58/59/68). Self-reported health and sexual history were ascertained. Risk factors for seropositivity and DNA positivity to hrHPV were assessed in separate Poisson regression models. RESULTS: The mean (SD) age of participants was 38.7 (6.1) years, and the median lifetime number of male sex partners was 7. Approximately two-thirds (68.1%) were seropositive for any hrHPV, 15.0% were DNA positive, and 70.7% were seropositive or DNA positive. In multivariate analyses, women who were married/living with a partner were less likely to be seropositive than single/separated women (adjusted prevalence ratio [aPR], 0.86; 95% confidence interval [CI], 0.75-0.98). Compared with never hormonal contraceptive users, current (aPR, 1.53; 95% CI, 1.01-2.29) or former (aPR, 1.64; 95% CI, 1.10-2.45) users were more likely to be seropositive. Women with a lifetime number of sex partners of 12 or more were more likely to be seropositive compared with those with 0 to 4 partners (aPR, 1.29; 95% CI, 1.06-1.56). Similar associations were seen with DNA positivity. In addition, there was a positive association between current smoking and hrHPV DNA (aPR vs. never smokers, 2.51; 95% CI, 1.40-4.49). CONCLUSIONS: Seventy-one percent of mid-adult women had evidence of current or prior hrHPV infection. Measures of probable increased exposure to HPV infection were associated with both seropositivity and DNA positivity to hrHPV, whereas current smoking was positively associated with hrHPV DNA only.

Short-term natural history of high-risk human papillomavirus infection in mid-adult women sampled monthly.

Characterizing short-term HPV detection patterns and viral load may inform HPV natural history in mid-adult women. From 2011-2012, we recruited women aged 30-50 years. Women submitted monthly self-collected vaginal samples for high-risk HPV DNA testing for 6 months. Positive samples were tested for type-specific HPV DNA load by real-time PCR. HPV type-adjusted linear and Poisson regression assessed factors associated with (i) viral load at initial HPV detection and (ii) repeat type-specific HPV detection. One-hundred thirty-nine women (36% of 387 women with ≥4 samples) contributed 243 type-specific HR HPV infections during the study; 54% of infections were prevalent and 46% were incident. Incident (vs. prevalent) detection and past pregnancy were associated with lower viral load, whereas current smoking was associated with higher viral load. In multivariate analysis, current smoking was associated with a 40% (95% CI: 5-87%) increase in the proportion of samples that were repeatedly positive for the same HPV type, whereas incident (vs. prevalent) detection status and past pregnancy were each associated with a reduction in the proportion of samples repeatedly positive (55%, 95% CI: 38-67% and 26%, 95% CI: 10-39%, respectively). In a separate multivariate model, each log10 increase in viral load was associated with a 10% (95% CI: 4-16%) increase in the proportion of samples repeatedly positive. Factors associated with repeat HPV detection were similar to those observed in longer-term studies, suggesting that short-term repeat detection may relate to long-term persistence. The negative associations between incident HPV detection and both viral load and repeat detection suggest that reactivation or intermittent persistence was more common than new acquisition.

Association of Human Papillomavirus 31 DNA Load with Risk of Cervical Intraepithelial Neoplasia Grades 2 and 3.

The association between human papillomavirus 31 (HPV31) DNA loads and the risk of cervical intraepithelial neoplasia grades 2 and 3 (CIN2-3) was evaluated among women enrolled in the atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) triage study (ALTS), who were monitored semiannually over 2 years and who had HPV31 infections detected at ≥1 visit. HPV31 DNA loads in the first HPV31-positive samples and in a random set of the last positive samples from women with ≥2 HPV31-positive visits were measured by a real-time PCR assay. CIN2-3 was histologically confirmed at the same time as the first detection of HPV31 for 88 (16.6%) of 530 women. After adjustment for HPV31 lineages, coinfection with other oncogenic types, and the timing of the first positive detection, the odds ratio (OR) per 1-log-unit increase in viral loads for the risk of a concurrent diagnosis of CIN2-3 was 1.5 (95% confidence interval [CI], 1.2 to 1.9). Of 373 women without CIN2-3 at the first positive visit who had ≥1 later visit, 44 had subsequent diagnoses of CIN2-3. The initial viral loads were associated with CIN2-3 diagnosed within 6 months after the first positive visit (adjusted OR, 1.5 [95% CI, 1.0 to 2.4]) but were unrelated to CIN2-3 diagnosed later. For a random set of 49 women who were tested for viral loads at the first and last positive visits, changes in viral loads were upward and downward among women with and without follow-up CIN2-3 diagnoses, respectively, although the difference was not statistically significant. Results suggest that HPV31 DNA load levels at the first positive visit signal a short-term but not long-term risk of CIN2-3.

Epidemiology of Human Papillomavirus Detected in the Oral Cavity and Fingernails of Mid-Adult Women.

BACKGROUND: Oral and fingernail human papillomavirus (HPV) detection may be associated with HPV-related carcinoma risk at these nongenital sites and foster transmission to the genitals. We describe the epidemiology of oral and fingernail HPV among mid-adult women. METHODS: Between 2011 and 2012, 409 women aged 30 to 50 years were followed up for 6 months. Women completed health and behavior surveys and provided self-collected oral, fingernail, and vaginal specimens at enrollment and exit for type-specific HPV DNA testing. Concordance of type-specific HPV detection across anatomical sites was described with κ statistics. Using generalized estimating equations or exact logistic regression, we measured the univariate associations of various risk factors with type-specific oral and fingernail HPV detection. RESULTS: Prevalence of detecting HPV in the oral cavity (2.4%) and fingernails (3.8%) was low compared with the vagina (33.1%). Concordance across anatomical sites was poor (κ < 0.20 for all comparisons). However, concurrent vaginal infection with the same HPV type (odds ratio [OR], 101.0; 95% confidence interval [CI], 31.4-748.6) and vaginal HPV viral load (OR per 1 log10 viral load increase, 2.2; 95% CI, 1.5-5.5) were each associated with fingernail HPV detection. Abnormal Papanicolaou history (OR, 11.1; 95% CI, 2.8-infinity), lifetime number of male vaginal sex partners at least 10 (OR vs. 0-3 partners, 5.0; 95% CI, 1.2-infinity), and lifetime number of open-mouth kissing partners at least 16 (OR vs. 0-15 partners, infinity; 95% CI, 2.6-infinity, by exact logistic regression) were each associated with oral HPV detection. CONCLUSIONS: Although our findings support HPV DNA deposition or autoinoculation between anatomical sites in mid-adult women, the rarity of HPV in the oral cavity and fingernails suggests that oral/fingernail HPV does not account for a significant fraction of HPV in genital sites.

Detection of Human Papillomavirus Infections at the Single-Cell Level.

OBJECTIVE: To explore the possibility of single-cell analysis of human papillomavirus (HPV) infection. METHODS: Two hundred and twenty cells were isolated by laser capture microdissection from formalin-fixed and paraffin-embedded cervical tissue blocks from 8 women who had HPV DNA detected in their cervical swab samples. The number of type-specific HPV copies in individual cells was measured by quantitative polymerase chain reaction with and without a prior reverse transcription. The cells were assayed and counted for more than once if the corresponding swab sample was positive for ≥2 HPV types. RESULTS: Infection with HPV16, HPV39, HPV51, HPV52, HPV58, HPV59 and HPV73 was detected in 12 (5.5%) of 220, 3 (9.4%) of 32, 3 (5.8%) of 52, 11 (22.9%) of 48, 9 (18.8%) of 48, 3 (9.4%) of 32 and none of 20 cells, respectively. The numbers of HPV genome copies varied widely from cell to cell. The coexistence of multiple HPV types was detected in 6 (31.6%) of 19 positive cells from 1 of the 6 women who had 2 or 3 HPV types detected in their swab samples. CONCLUSION: Given the heterogeneity of HPV status in individual cells, further clarification of HPV infection at the single-cell level may refine our understanding of HPV-related carcinogenesis.

High rates of incident and prevalent anal human papillomavirus infection among young men who have sex with men.

BACKGROUND: There are few published estimates of anal human papillomavirus (HPV) infection rates among young men who have sex with men (YMSM). METHODS: We estimated incidence and prevalence of type-specific anal HPV infection using clinician-collected anal swabs for HPV DNA testing obtained during a 1-year prospective study of 94 YMSM (mean age, 21 years) in Seattle. RESULTS: Seventy percent of YMSM had any HPV infection detected during the study, and HPV-16 and/or -18 were detected in 37%. The incidence rate for any new HPV infection was 38.5 per 1000 person-months and 15.3 per 1000 person-months for HPV-16/18; 19% had persistent HPV-16/18 infection. No participant tested positive for all 4 HPV types in the quadrivalent vaccine. The number of lifetime male receptive anal sex partners was significantly associated with HPV infection. The prevalence of HPV-16/18 was 6% among YMSM with a history of 1 receptive anal sex partner and 31% among YMSM with ≥ 2 partners. CONCLUSIONS: Although the high prevalence of HPV among YMSM highlights the desirability of vaccinating all boys as a strategy to avert the morbidity of HPV infection, most YMSM appear to remain naive to either HPV-16 or -18 well into their sexual lives and would benefit from HPV immunization.

Viral load and short-term natural history of type-specific oncogenic human papillomavirus infections in a high-risk cohort of midadult women.

Oncogenic human papillomavirus (HPV) viral load may inform the origin of newly detected infections and characterize oncogenic HPV natural history in midadult women. From 2007 to 2011, we enrolled 521 25-65-year-old-female online daters and followed them triannually with mailed health and sexual behavior questionnaires and kits for self-sampling for PCR-based HPV DNA testing. Samples from oncogenic HPV positive women were selected for type-specific DNA load testing by real-time PCR with adjustment for cellularity. Linear or logistic regression models were used to evaluate relationships between viral levels, health and sexual behavior, and longitudinal oncogenic HPV detection. Type-specific viral levels were borderline significantly higher in oncogenic HPV infections that were prevalent versus newly detected (p = 0.092), but levels in newly detected infections were higher than in infections redetected after intercurrent negativity (p < 0.001). Recent sex partners were not significantly associated with viral levels. Compared with prevalent infections detected intermittently, the likelihood of persistent (OR = 4.31, 95% CI: 2.20-8.45) or single-time (OR = 1.32, 95% CI: 1.03-1.71) detection increased per 1-unit increase in baseline log10 viral load. Viral load differences between redetected and newly detected infections suggest a portion of new detections were due to new acquisition, although report of recent new sex partners (a potential marker of new infection) was not predictive of viral load; oncogenic HPV infections in midadult women with new partners likely represent a mix of new acquisition and reactivation or intermittent detection of previous infection. Intermittent detection was characterized by low viral levels, suggesting that intermittent detection of persisting oncogenic HPV infection may be of limited clinical significance.

Would young women attending sexually transmitted disease clinics benefit from human papillomavirus vaccination? An assessment of human papillomavirus DNA and seropositivity from human papillomavirus sentinel surveillance, 2003-2005.

BACKGROUND: There are limited data on the proportion who have been exposed to vaccine-type human papillomavirus (HPV) among women attending sexually transmitted disease (STD) clinics; this information could inform the potential benefits of HPV vaccination for women attending this venue. METHODS: Human papillomavirus surveillance was conducted in STD clinics in Baltimore, MD; Boston, MA; Denver, CO; Los Angeles, CA; and Seattle, WA, among women receiving cervical cancer screening from January 2003 to December 2005. The women had specimens collected for cervical cytology HPV testing by L1 consensus polymerase chain reaction testing and serologic assessment for HPV 6, 11, 16, and 18 using the competitive Luminex immunoassay. Results from 880 women with adequate specimens were included. Women were HPV naïve if they were both HPV DNA negative and seronegative for a specific HPV type. RESULTS: One hundred seventy women (19.3%) had HPV 16, 18, 6, or 11 DNA, and 418 (47.5%) were HPV 16, 18, 6, or 11 seropositive. Four hundred ten (46.6%) women were naïve to all 4 types, 570 (64.8%) were naïve to both HPV 16 and 18, and 545 (61.9%) were naïve to both HPV 6 and 11. Almost all (99.3%) women were naïve to at least 1 vaccine HPV type. CONCLUSIONS: Almost half of young women age eligible for HPV vaccine and attending STD clinics were naïve to all 4 HPV types, and more than half were naïve to both HPV 16 and 18. This assessment suggests that most young women attending this venue might benefit from HPV vaccination.

Persistence of newly detected human papillomavirus type 31 infection, stratified by variant lineage.

Variants of human papillomavirus (HPV) type 31 have been shown to be related both to risk of cervical lesions and racial composition of a population. It is largely undetermined whether variants differ in their likelihood of persistence. Study subjects were women who participated in the ASCUS-LSIL Triage Study and who had a newly detected HPV31 infection during a two-year follow-up with six-month intervals. HPV31 isolates were characterized by sequencing and assigned to one of three variant lineages. Loss of the newly detected HPV31 infection was detected in 76 (47.5%) of the 160 women (32/67 with A variants, 16/27 with B variants and 28/66 with C variants). The adjusted hazard ratio associating loss of the infection was 1.2 (95% CI, 0.7-2.1) for women with A variants and 2.1 (95% CI, 1.2-3.5) for women with B variants when compared with those with C variants. Infections with A and C variants were detected in 50 and 41 Caucasian women and in 15 and 23 African-American women, respectively. The likelihood of clearance of the infection was significantly lower in African-American women with C variants than in African-American women with A variants (p = 0.05). There was no difference in the likelihood of clearance between A and C variants among Caucasian women. Our data indicated that infections with B variants were more likely to resolve than those with C variants. The difference in clearance of A vs. C variants in African-Americans, but not in Caucasians, suggests a possibility of the race-related influence in retaining the variant-specific infection.

Association of human papillomavirus type 31 variants with risk of cervical intraepithelial neoplasia grades 2-3.

Although the lineages of human papillomavirus type 31 (HPV31) variants are recognized, their clinical relevance is unknown. The purpose of our study was to examine risk of cervical intraepithelial neoplasia Grades 2-3 (CIN2/3) by HPV31 variants. Study subjects were women who participated in the atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion Triage Study and who had HPV31 infections detected at one or more visits. They were followed semi-annually over 2 years for detection of HPV DNA and cervical lesion. HPV31 isolates were characterized by DNA sequencing and assigned into 1 of 3 variant lineages. CIN2/3 was histologically confirmed in 127 (27.0%) of the 470 HPV31-positive women, 83 diagnosed at the first HPV31-positive visit and 44 thereafter. The odds ratio for the association of 2-year cumulative risk of CIN2/3 was 1.7 (95% CI: 1.0-2.9) for infections with A variants and 2.2 (95% CI: 1.2-3.9) for infections with B variants as compared to those with C variants. Among women without CIN2/3 at the first HPV31-positive visit, the risk of subsequent CIN2/3 was 2.2-fold greater for those with A variants (95% CI: 1.0-4.8) and 2.0-fold greater for those with B variants (95% CI: 0.9-4.9) as compared to those with C variants. Similar associations were observed when CIN3 was used as the endpoint. The findings from our study help to tag HPV31 variants that differ in risk of CIN2/3 and to explain in part why some HPV31 infections regress spontaneously and others lead to disease progression.

Prevalence and risk factors for oncogenic human papillomavirus infections in high-risk mid-adult women.

BACKGROUND: The epidemiology of high-risk (hr) human papillomavirus (HPV) infections in mid-adult women with new sex partners is undefined. METHODS: We analyzed baseline data from 518 25- to 65-year-old women online daters. Women were mailed questionnaires and kits for self-collecting vaginal specimens for polymerase chain reaction-based hrHPV testing. Risk factors for infection were identified using Poisson regression models to obtain prevalence ratios (PRs). RESULTS: The prevalence of hrHPV infection was 35.9%. In multivariate analysis restricted to sexually active women, the likelihood of hrHPV infection was associated with abnormal Papanicolaou test history (PR = 1.42, 95% confidence interval [CI]: 1.10-1.84), lifetime number of sex partners >14 (compared with 1-4; PR = 2.13, 95% CI: 1.13-4.02 for 15-24 partners; and PR = 1.91, 95% CI: 1.00-3.64 for ≥25 partners), male partners with ≥1 concurrent partnership (PR = 1.34, 95% CI: 1.05-1.71), and male partners whom the subject met online (PR = 1.39, 95% CI: 1.08-1.79). Age was inversely associated with infection only in women who were sexually inactive (PR = 0.67 per 5-year age difference, adjusted for Papanicolaou history and lifetime number of partners). Compared with sexually inactive women, the likelihood of infection increased with increasing risk level (from low-risk to hr partners; P < 0.0001 by trend test). In multivariate analysis, infection with multiple versus single hrHPV types was inversely associated with ever having been pregnant (PR = 0.64, 95% CI: 0.46-0.90) and recent consistent condom use (PR = 0.56, 95% CI: 0.32-0.97), and positively associated with genital wart history (PR = 1.43, 95% CI: 1.03-1.99). CONCLUSIONS: Measures of both cumulative and recent sexual history were associated with prevalent hrHPV infection in this hr cohort of mid-adult women.

Rates and determinants of oral human papillomavirus infection in young men.

BACKGROUND: Little is known about the rates and determinants of oral human papillomavirus (HPV) infection, an infection that is etiologically linked with oropharyngeal cancers. METHODS: A cohort of male university students (18-24 years) was examined every 4 months (212 men, 704 visits). Oral specimens were collected via gargle/rinse and swabbing of the oropharynx. Genotyping for HPV-16 and 36 other α-genus types was performed by polymerase chain reaction-based assay. Data on potential determinants were gathered via clinical examination, in-person questionnaire, and biweekly online diary. Hazards ratios (HR) were used to measure associations with incident infection. RESULTS: Prevalence of oral HPV infection at enrollment was 7.5%, and 12-month cumulative incidence was 12.3% (95% confidence interval [CI], 7.0, 21.3). Prevalence of oral HPV-16 was 2.8% and 12-month cumulative incidence was 0.8% (95% CI, 0.1%-5.7%). None of the incident oral HPV infections and 28.6% of the prevalent oral HPV infections were detected more than once. In a multivariate model, incident oral HPV infection was associated with recent frequency of performing oral sex (≥1 per week: HR, 3.7; 95% CI, 1.4-9.8), recent anal sex with men (HR, 42.9; 95% CI, 8.8-205.5), current infection with the same HPV type in the genitals (HR, 6.2; 95% CI, 2.4-16.4), and hyponychium (HR, 11.8, 95% CI, 4.1-34.2). CONCLUSIONS: Although nearly 20% of sexually active male university students had evidence of oral HPV infection within 12 months, most infections were transient. Human papillomavirus type 16 was not common. Sexual contact and autoinoculation appeared to play independent roles in the transmission of α-genus HPV to the oral cavity of young men.

Disclosure of genital human papillomavirus infection to female sex partners by young men.

A survey was administered to male university students who tested positive for high-risk human papillomavirus. Disclosure was more likely in men with fewer partners, in main partnerships, and in longer partnerships. Disclosure was associated with discussing the Pap test/human papillomavirus vaccine with female partners and not associated with a worsening relationship.

Serum antibody response following genital {alpha}9 human papillomavirus infection in young men.

Background. Although the prevalence of human papillomavirus (HPV) genital infection is similarly high in males and females, seroprevalence is lower in males. This study assessed rates and determinants of seroconversion after detection of genital HPV infection in young men. Methods. We investigated HPV type-specific seroconversion in a cohort of heterosexual male university students who had an α9 HPV type (HPV-16, -31, -33, -35, -52, -58, or -67) detected in the genital tract (n = 156). HPV DNA and antibodies were detected and typed using liquid bead-based multiplex assays. We calculated seroconversion using Kaplan-Meier survival analysis. Cox proportional hazards models with generalized estimating equations were used to examine associations with seroconversion. Results. Within 24 months of detecting genital HPV infection, type-specific seroconversion ranged from 4% for HPV-52 to 36% for HPV-31. HPV-16 seroconversion at 24 months was 13% (95% confidence interval [CI], 7%-25%). Among incident HPV infections, ever cigarette smoking and infection site(s) (shaft/scrotum and glans/urine vs shaft/scrotum or glans/urine only) were positively associated with type-specific seroconversion. Conclusions. For each of the α9 HPV types, type-specific seroconversion within 24 months was observed in 36% or less of infected men. Seroconversion might be related to cigarette smoking and genital site(s) infected.

Viral load in the natural history of human papillomavirus type 16 infection: a nested case-control study.

BACKGROUND: Viral load may influence the course of human papillomavirus type 16 (HPV-16) infection. METHODS: This case-control study was nested within the 2-year Atypical Squamous Cells of Undetermined Significance and Low-Grade Squamous Intraepithelial Lesion Triage Study, in which women were followed semiannually for HPV and cervical intraepithelial neoplasia (CIN). Case patients (n = 62) were women diagnosed with CIN3 following HPV-16-positive detection at a follow-up visit. HPV-16-positive controls (n = 152) without CIN2 or CIN3 were matched to cases based on the follow-up visit in which viral load was measured. Real-time polymerase chain reaction was used for HPV-16 DNA quantification. RESULTS: The risk of CIN3 increased with increasing HPV-16 DNA load at the follow-up visit (odds ratio, 1.63; 95% confidence interval, 1.33-1.99 per 1 log(10) unit increase); the association was not affected by whether HPV-16 was present at enrollment. When HPV-16 was present at both enrollment and follow-up, viral load remained high among cases (P = .77) but decreased substantially among controls (P = .004). Among women with HPV-16 found initially during follow-up, viral load in the first HPV-16-positive sample was associated with short-term persistence; load was higher in those with infection, compared with those without infection, 1 visit after the initial positivity (P = .001). CONCLUSIONS: Viral load of newly detected infections and changes in viral load predict persistence and progression of HPV-16 infections.