Prevalence of Alpha, Beta, and Gamma Human Papillomaviruses in Patients With Head and Neck Cancer and Noncancer Controls and Relation to Behavioral Factors.

BACKGROUND: Human papillomaviruses (HPVs) cause head and neck cancer (HNC), which is increasing in incidence in developed countries. We investigated the prevalence of alpha (α), beta (ß), and gamma (γ) HPVs among HNC cases and controls, and their relationship with sociodemographic, behavioral, and oral health factors. METHODS: We obtained oral rinse and brush samples from incident HNC cases (n = 369) and hospital-based controls (n = 439) and tumor samples for a subsample of cases (n = 121). We genotyped samples using polymerase chain reaction with PGMY09-PGMY11 primers and linear array for α-HPV and type-specific multiplex genotyping assay for ß-HPV and γ-HPV. Sociodemographic and behavioral data were obtained from interviews. RESULTS: The prevalence of α-, ß-, and γ-HPV among controls was 14%, 56%, and 24%, respectively, whereas prevalence among cases was 42%, 50%, and 33%, respectively. Prevalence of α- and γ-HPV, but not ß-HPV, increased with increase in sexual activity, smoking, and drinking habits. No HPV genus was associated with oral health. Tumor samples included HPV genotypes exclusively from the α-genus, mostly HPV-16, in 80% of cases. CONCLUSIONS: The distribution of α- and γ-HPV, but not ß-HPV, seems to vary based on sociodemographic and behavioral characteristics. We did not observe the presence of cutaneous HPV in tumor tissues.

Detection and Clearance of Type-Specific and Phylogenetically Related Genital Human Papillomavirus Infections in Young Women in New Heterosexual Relationships.

BACKGROUND: Understanding the natural history of human papillomavirus (HPV) infections is essential to cervical cancer prevention planning. We estimated HPV type-specific infection detection and clearance in young women. METHODS: The HPV Infection and Transmission among Couples through Heterosexual activity (HITCH) study is a prospective cohort of 502 college-age women who recently initiated a heterosexual relationship. We tested vaginal samples collected at 6 clinical visits over 24 months for 36 HPV types. Using rates and Kaplan-Meier analysis, we estimated time-to-event statistics with 95% confidence intervals (CIs) for detection of incident infections and clearance of incident and present-at-baseline infections (separately). We conducted analyses at the woman- and HPV-levels, with HPV types grouped by phylogenetic relatedness. RESULTS: By 24 months, we detected incident infections in 40.4% (CI, 33.4%-48.4%) of women. Incident subgenus 1 (43.4; CI, 33.6-56.4), 2 (47.1; CI, 39.9-55.5), and 3 (46.6; CI, 37.7-57.7) infections cleared at similar rates per 1000 infection-months. We observed similar homogeny in HPV-level clearance rates among present-at-baseline infections. CONCLUSIONS: Our analyses provide type-specific infection natural history estimates for cervical cancer prevention planning. HPV-level analyses did not clearly indicate that high oncogenic risk subgenus 2 infections persist longer than their low oncogenic risk subgenera 1 and 3 counterparts.

Use of a carrageenan-based gel had no impact on anal HPVs 16 and 18 viral loads in gay, bisexual, and other men who have sex with men.

The Lubricant Investigation in Men to Inhibit Transmission of human papillomavirus (HPV) Infection randomized control trial in gay, bisexual, and other men who have sex with men (gbMSM) found that carrageenan use neither reduced acquisition of anal HPV infections nor influenced infection clearance. To investigate carrageenan's lack of protective effect, we compared the change in anal HPV16 and HPV18 viral loads following carrageenan use against placebo. We restricted our analysis to participants who completed the first four study visits and had a valid baseline sample (n = 161, 54 HIV-positive). Samples were tested for HPV detection using the linear array PCR assay. HPV16- and/or HPV18-positive samples were tested for viral load using real-time PCR. For participants who tested HPV16- (n = 29) or HPV18-positive (n = 10) at least once across visits 1-4, we compared the change in type-specific viral load between study arms using the Mann-Whitney U test. Although the median net change in HPV16 and HPV18 viral loads across visits 1-4 was higher in the treatment than placebo arm (HPV16: 0.68 vs. 0.18 copies/cell, p = 0.60; HPV18: 18.32 vs. 10.12 copies/cell, p = 0.52), these differences were not statistically significant. Results were similar by HIV status. Carrageenan use did not impact anal HPV16 or HPV18 viral loads, which may further explain its lack of protective effect in gbMSM.

Impact of a carrageenan gel on viral load of genital human papillomavirus infections in sexually active women: Findings from the Carrageenan-gel Against Transmission of Cervical Human papillomavirus (CATCH) trial.

Previous research has shown that women's use of a carrageenan gel reduces the risk of acquiring genital human papillomavirus (HPV) infections but does not help to clear existing ones. Although gel use may not result in complete clearance, it may decrease the viral load of HPV infections. We tested this hypothesis in the Carrageenan-gel Against Transmission of Cervical Human papillomavirus (CATCH) randomized controlled trial. Participants of the CATCH study were selected for viral load testing if they had completed the first four study visits and tested positive for HPV42 or HPV51 in at least one of these visits. HPV42 and HPV51 were chosen as they were among the most abundant low- and high-risk types, respectively, in the study sample. We measured viral load with a type-specific real-time polymerase chain reaction. Results were displayed using summary statistics. Of 461 enrolled participants, 39 were included in the HPV42 analysis set and 56 in the HPV51 analysis set. The median time between visits 1 and 4 was 3.7 months. The viral load (copies/cell) of HPV42 ranged from <0.001 to 13 434.1, and that of HPV51 from <0.001 to 967.1. The net median change in HPV42 viral load over all four visits was -1.04 copies/cell in the carrageenan and -147 copies/cell in the placebo arm (Wilcoxon rank sum test, p = 0.26). There was no net median change in HPV51 viral load over all four visits in either arm (p = 0.45). The use of a carrageenan-based gel is unlikely to reduce the viral load of HPVs 42 or 51.

Efficacy of a Carrageenan Gel in Increasing Clearance of Anal Human Papillomavirus Infections in Men: Interim Analysis of a Double-Blind, Randomized Controlled Trial.

Preclinical studies have demonstrated carrageenan's anti-human papillomavirus (HPV) activity. We assessed efficacy of a carrageenan-based gel compared to a placebo gel in increasing the clearance of anal HPV infections among gay, bisexual, and other men who have sex with men (gbMSM). Of 255 enrolled gbMSM, 134 were HPV positive at baseline and had valid HPV results for ≥2 visits. Carrageenan did not differ from placebo in clearing all baseline infections (hazard ratio, 0.84 [95% confidence interval, .31-2.27]), based on having 2 consecutive HPV-negative visits following at least 1 HPV-positive visit. There were no remarkable differences for analyses at the HPV type level or by human immunodeficiency virus status. CLINICAL TRIALS REGISTRATION: NCT02354144.

Serologic Response to Human Papillomavirus Genotypes Among Unvaccinated Women: Findings From the HITCH Cohort Study.

BACKGROUND: Humoral immune responses may be critical for preventing, controlling, and/or eliminating human papillomavirus (HPV) infection. We analyzed humoral response to natural HPV infection considering phylogenetic relatedness among unvaccinated women. METHODS: We included 399 young women attending university/college in Montreal, Canada who were participants of the HITCH cohort. Participants provided blood samples at baseline and 5 follow-up visits. Antibody response to bacterially expressed L1 and E6 glutathione S-transferase (GST) fusion proteins, and virus-like particles (VLP-L1) of Alphapapillomavirus types were measured using multiplex serology. We assessed correlations and associations between HPV types at baseline using Pearson correlation coefficients (r) and univariable linear regressions. RESULTS: At baseline, > 40% were seropositive for GST-L1 antibodies of at least 1 HPV type. Strong correlations between GST-L1 were observed for α9 HPV types: 58-52 (r = 0.86), 58-33 (r = 0.75), 33-52 (r = 0.72), and between GST-E6: 52-11 (r = 0.84), 52-18 (r = 0.79), 58-33 (r = 0.78), 35-11 (r = 0.76). HPV16 VLP-L1 moderately explained variability in HPV16 GST-L1 (regression coefficient [b] = 0.38, R2 = 43.1%), and HPV45 GST-L1 in HPV18 GST-L1 (b = 0.68, R2 = 42.8%). GST-E6 antibodies accounted for a low to moderate proportion of variability in HPV16 and HPV18 GST-E6 (R2 = 6.4%-62.2%). CONCLUSIONS: Associations between naturally induced HPV-specific antibodies depend on phylogenetic relatedness.

Vaccine Effectiveness Against 12-Month Incident and Persistent Anal Human Papillomavirus Infection Among Gay, Bisexual, and Other Men Who Have Sex With Men.

BACKGROUND: Real-world evidence of human papillomavirus (HPV) vaccine effectiveness (VE) against longitudinal outcomes is lacking among gay, bisexual, and other men who have sex with men (GBM). We compared 12-month incidence and persistence of anal HPV infection between vaccinated and unvaccinated GBM. METHODS: We recruited GBM aged 16-30 years in Montreal, Toronto, and Vancouver, Canada, from 2017 to 2019. Participants were followed over a median of 12 months (interquartile range, 12-13 months). Participants self-reported HPV vaccination and self-collected anal specimens for HPV DNA testing. We calculated prevalence ratios (PR) for 12-month cumulative incidence and persistence with ≥1 quadrivalent vaccine type (HPV 6/11/16/18) between vaccinated (≥1 dose at baseline) and unvaccinated participants using a propensity score-weighted, modified Poisson regression. RESULTS: Among 248 participants, 109 (44.0%) were vaccinated at baseline, of whom 62.6% received 3 doses. PRs for HPV 6/11/16/18 were 0.56 (95% confidence interval [CI], .24-1.31) for cumulative incidence and 0.53 (95% CI, .25-1.14) for persistence. PRs were 0.23 (95% CI, .05-1.03) and 0.08 (95% CI, .01-.59) for incidence and persistence, respectively, among participants who received their first dose at age ≤23 years and 0.15 (95% CI, .03-.68) and 0.12 (95% CI, .03-.54) among participants who were sexually active for ≤5 years before vaccination. CONCLUSIONS: Findings support national recommendations for HPV vaccination at younger ages or soon after sexual debut.

Role of Human Leukocyte Antigen Allele Sharing in Human Papillomavirus Infection Transmission Among Heterosexual Couples: Findings From the HITCH Cohort Study.

BACKGROUND: Human leukocyte antigen (HLA) polymorphism influences innate and adaptive immune responses. Among heterosexual couples in the HPV Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) cohort study, we examined whether allele sharing in a couple predicted the partners' infections with the same human papillomavirus (HPV) type. METHODS: We tested genital samples from 271 couples for 36 HPV genotypes by polymerase chain reaction. We used direct DNA sequencing to type HLA-B07, -DRB1, -DQB1 and -G. Generalized estimating equations were used to examine the associations between the extent of allele sharing and HPV type concordance in which at least 1 of the partners was HPV positive. RESULTS: We identified 106 different HLA alleles. The most common HLA alleles among couples were G*01:01:01 (95.6%), G*01:01:02 (60.1%), DQB1*03:01 (57.2%), and DRB1*07:01 (46.9%). Allele sharing was as follows: 19.6% shared none, 43.2% shared 1 only, 25.1% shared 2, and 12.5% shared 3-5. Irrespective of HLA class, grouped or in combination, the extent of allele sharing was not a significant predictor of type-specific HPV concordance in a couple (odds ratio, 1.1 [95% confidence interval, .5-2.1], for 3-5 vs none). CONCLUSIONS: We found no evidence that the extent of HLA allele concordance influences the likelihood of HPV transmission in newly formed heterosexual couples.

Male Circumcision and Genital Human Papillomavirus (HPV) Infection in Males and Their Female Sexual Partners: Findings From the HPV Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) Cohort Study.

BACKGROUND: Previous studies examining the association between male circumcision (MC) and human papillomavirus (HPV) infections have reported inconsistent results. We used data from the HPV Infection and Transmission Among Couples Through Heterosexual Activity (HITCH) cohort study to examine the association between MC and HPV infections in males and their female sexual partners. METHODS: We enrolled monogamous couples in a longitudinal study between 2005 and 2011 in Montreal, Canada. We used logistic and Poisson regression models with propensity score adjustment to estimate odds ratios (ORs) and rate ratios for the association between MC and the prevalence, transmission, and clearance of HPV infections. RESULTS: Four hundred thirteen couples were included in our study. The prevalence OR for the association between MC and baseline infections was 0.81 (95% confidence interval [CI], .56-1.16) in males and 1.05 (95% CI, .75-1.46) in females. The incidence rate ratio for infection transmission was 0.59 (95% CI, .16-2.20) for male-to-female transmission and 0.77 (95% CI, .37-1.60) for female-to-male transmission. The clearance rate ratio for clearance of infections was 0.81 (95% CI, .52-1.24). CONCLUSIONS: We found little evidence of an association between MC and HPV infection prevalence, transmission, or clearance in males and females. Further longitudinal couple-based studies are required to investigate this association.

Proportion of Incident Genital Human Papillomavirus Detections not Attributable to Transmission and Potentially Attributable to Latent Infections: Implications for Cervical Cancer Screening.

BACKGROUND: Infections with human papillomaviruses (HPVs) may enter a latent state, and eventually become reactivated following loss of immune control. It is unclear what proportion of incident HPV detections are reactivations of previous latent infections vs new transmissions. METHODS: The HPV Infection and Transmission among Couples through Heterosexual activity (HITCH) cohort study prospectively followed young newly formed heterosexual partners recruited between 2005 and 2011 in Montréal, Canada. We calculated the fraction of incident HPV detections nonattributable to sexual transmission risk factors with a Bayesian Markov model. Results are the median (2.5th-97.5th percentiles) of the estimated posterior distribution. RESULTS: A total of 544 type-specific incident HPV detection events occurred in 849 participants; 33% of incident HPV detections occurred in participants whose HITCH partners were negative for that HPV type and who reported no other sex partners over follow-up. We estimate that 43% (38%-48%) of all incident HPV detections in this population were not attributable to recent sexual transmission and might be potentially reactivation of latent infections. CONCLUSIONS: A positive HPV test result in many cases may be a reactivated past infection, rather than a new infection from recent sexual behaviors or partner infidelity. The potential for reactivation of latent infections in previously HPV-negative women should be considered in the context of cervical cancer screening.

Human papillomavirus genotype concordance between Anyplex II HPV28 and linear array HPV genotyping test in anogenital samples.

Anyplex II HPV-28 (HPV-28) can detect individually 28 HPV genotypes. We assessed the agreement between linear array HPV genotyping (LA-HPV) and HPV-28 for detection of 27 HPV genotypes in 410 stored anogenital samples (75 anal samples, 335 physician-collected cervical samples) collected over 5 years from 410 individuals (13 men, 397 women), including 202 HIV-seropositive individuals. HPV DNA was detected in 393 (95.9%, 95% confidence interval [CI]: 93.4-97.4) and 382 (93.2%, 95% CI: 90.3-95.3) samples with HPV-28 and LA-HPV (p = 0.13), respectively, for a good agreement of 96.3% (κ = 0.65). Of the 10503 HPV typing results, 10195 (780 positive, 9577 negative) were concordant, for an agreement of 97.1% (95% CI: 96.7-97.4) and an excellent of κ = 0.82 (95% CI: 0.80-0.84). The mean type-specific concordance for 27 genotypes was 97.0%, 95% CI: 95.8-98.5 (κ = 0.86 ± 0.07, 95% CI: 0.83-0.88). Excellent agreement was obtained individually for all high-risk genotypes (κ = 0.81-0.97) and for most other genotypes except for types 42, 44, 54, 68, and 69. The mean number of types per sample in discordant samples detected with LA-HPV (3.0, 95% CI: 2.7-3.4) was greater than in concordant samples (1.4, 95% CI: 1.3-1.5; p< 0.001). In conclusion, HPV-28 compared favorably with LA-HPV, but was more frequently positive for HPV42 and HPV68.

Natural spring water gargle samples as an alternative to nasopharyngeal swabs for SARS-CoV-2 detection using a laboratory-developed test.

The objective of this study was to validate the use of spring water gargle (SWG) as an alternative to oral and nasopharyngeal swab (ONPS) for SARS-CoV-2 detection with a laboratory-developed test. Healthcare workers and adults from the general population, presenting to one of two COVID-19 screening clinics in Montréal and Québec City, were prospectively recruited to provide a gargle sample in addition to the standard ONPS. The paired specimens were analyzed using thermal lysis followed by a laboratory-developed nucleic acid amplification test (LD-NAAT) to detect SARS-CoV-2, and comparative performance analysis was performed. An individual was considered infected if a positive result was obtained on either sample. A total of 1297 adult participants were recruited. Invalid results (n = 18) were excluded from the analysis. SARS-CoV-2 was detected in 144/1279 (11.3%) participants: 126 from both samples, 15 only from ONPS, and 3 only from SWG. Overall, the sensitivity was 97.9% (95% CI: 93.7-99.3) for ONPS and 89.6% (95% CI: 83.4-93.6; p = 0.005) for SWG. The mean ONPS cycle threshold (Ct ) value was significantly lower for the concordant paired samples as compared to discordant ones (22.9 vs. 32.1; p < 0.001). In conclusion, using an LD-NAAT with thermal lysis, SWG is a less sensitive sampling method than the ONPS. However, the higher acceptability of SWG might enable a higher rate of detection from a population-based perspective. Nonetheless, in patients with a high clinical suspicion of COVID-19, a repeated analysis with ONPS should be considered. The sensitivity of SWG using NAAT preceded by chemical extraction should be evaluated.

Efficacy of a carrageenan gel in preventing anal human papillomavirus (HPV) infection: interim analysis of the Lubricant Investigation in Men to Inhibit Transmission of HPV Infection (LIMIT-HPV) randomised controlled trial.

BACKGROUND: Carrageenan, a non-toxic gelling agent derived from red algae, has potent anti-human papillomavirus (HPV) activity in in vitro and animal studies. We assessed, in an interim analysis, the efficacy of a carrageenan-based gel in reducing the risk of new detections of anal HPV among gay, bisexual and other men who have sex with men (gbMSM). METHODS: The LIMIT-HPV study (Lubricant Investigation in Men to Inhibit Transmission of HPV Infection) is a phase IIb, double-blind, placebo-controlled randomised controlled trial conducted in Montreal, Canada. gbMSM were randomly assigned (1:1) to receive a carrageenan-based or placebo gel. Participants were instructed to apply the gel to the anus, condom and/or partners' penis before and-as required-during receptive anal intercourse. Questionnaire data and anal samples were collected at 0, 1, 2, 3, 6, 9 and 12 months. We estimated new detections of anal HPV infection(s) detected via Linear Array using Cox proportional hazards models. RESULTS: Participants recruited from February 2016 to December 2019 were randomly assigned to the carrageenan (n=127) or placebo (n=128) arm. The efficacy and safety analyses included 201 and 210 participants. The median follow-up time was 7.6 months (range: 0-28.5) in the carrageenan group and 9.3 months (range: 0-40.7) in the placebo group. The HR for new detections was 1.21 (95% CI 0.86 to 1.70): 69.4% and 65.1% new detections of HPV in the carrageenan and placebo arms, respectively. More adverse events were reported in the carrageenan (59.8%) compared with the placebo (39.8%) arm. CONCLUSIONS: The interim analysis did not demonstrate a protective effect of carrageenan on the risk of new detections of anal HPV infection among gbMSM. Carrageenan gel use was associated with a higher proportion of adverse events. Given these findings and the (assumed) low probability that a beneficial effect would be found by the study's end, the trial was terminated as recommended by the Data Safety and Monitoring Board. TRIAL REGISTRATION NUMBER: NCT02354144.

Risk factors for placental human papillomavirus infection.

OBJECTIVE: Human papillomavirus (HPV) has been associated with adverse pregnancy outcomes but placental HPV infection has been rarely studied. The objective was to determine the proportion of HPV-positive placentas and the associated risk factors among HPV-positive women during pregnancy. METHODS: We analysed data from pregnant women enrolled in HERITAGE cohort study between 2010 and 2016 with positive vaginal HPV infection during the first trimester of pregnancy (n=354). Placental swabs and biopsies were collected. HPV genotyping was performed using Linear Array. The predictors of placental HPV detection were identified by generalised estimating equations models. RESULTS: HPV was detected in 78 placentas (22.0%) (one among 96 caesarean sections and 77 among 258 vaginal deliveries). Overall, 91% of HPV-positive placentas were positive for a genotype that was detected in vaginal samples during pregnancy. Among women who delivered vaginally, abnormal cytology (adjusted OR (aOR) 1.78 (95% CI 1.02 to 3.10)), other genitourinary infection (aOR 2.41 (95% CI 1.31 to 4.44)), presence of multiple HPV genotypes in the first trimester (aOR 2.69 (95% CI 1.76 to 4.12)) and persistence of high-risk HPV infections during pregnancy (HPV-16/18: aOR 3.94 (95% CI 2.06 to 7.55) and other than HPV-16/18: aOR 2.06 (95% CI 1.05 to 4.02)) were independently associated with placental HPV. CONCLUSIONS: HPV was frequently detected in the placenta of women who delivered vaginally and may be associated with host immune response characteristics.

Protection to Self and to One's Sexual Partner After Human Papillomavirus Vaccination: Preliminary Analysis From the Transmission Reduction And Prevention with HPV Vaccination Study.

BACKGROUND: It is unknown whether recently human papillomavirus (HPV)-vaccinated individuals confer protection against vaccine-preventable HPV types to their partners. METHODS: Participants 18 to 45 years old who were living in Montreal, Canada, and in a heterosexual relationship of 6 months or less were randomly assigned to receive the intervention HPV vaccine, Gardasil or Gardasil 9, or active control (AC), Avaxim, a hepatitis A vaccine. Couples attended a maximum of 6 clinic visits (baseline and at 2, 4, 6, 9, and 12 months) and provided genital samples for detection of 36 HPV genotypes. Participants were vaccinated at baseline and at 2 and 6 months. We used Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between the administered vaccine and infections at the HPV episode level. RESULTS: We restricted analyses to 273 participants (intervention: n = 141, AC: n = 132) who had at least 2 visits with valid HPV data. The HR of becoming positive for a given vaccine-preventable HPV type in the intervention group among those who received at least 1 dose compared with AC was 0.47 (95% CI, 0.23-0.97). Comparing individuals with HPV-vaccinated versus AC-vaccinated partners, there was no difference in risk of becoming positive for a given vaccine-preventable HPV type among those whose partners received at least 1 (HR, 1.46; 95% CI, 0.73-2.94) or 2 (HR, 0.78; 95% CI, 0.31-1.96) doses. CONCLUSIONS: Our study provides inconclusive evidence that individuals whose partner recently received an HPV vaccine are protected from vaccine-preventable types but demonstrates that vaccinated individuals are at a lower risk of incident infections.Trial Registration Number: NCT01824537.

Anal Human Papillomavirus Prevalence Among Vaccinated and Unvaccinated Gay, Bisexual, and Other Men Who Have Sex With Men in Canada.

BACKGROUND: Starting in 2015, human papillomavirus (HPV) vaccine has been publicly funded for gay, bisexual, and other men who have sex with men (GBM) 26 years or younger in Canada. METHODS: Self-identified GBM who reported having sex with another man within the past 6 months were enrolled using respondent-driven sampling (RDS) between February 2017 and August 2019 in Montreal, Toronto, and Vancouver, Canada. Men aged 16 to 30 years self-collected anal specimens for HPV-DNA testing. Prevalence was estimated using RDS-II weights. We compared the prevalence of quadrivalent (HPV-6/11/16/18) and 9-valent (HPV-6/11/16/18/31/33/45/52/58) vaccine types between GBM who self-reported HPV vaccination (≥1 dose) and those reporting no vaccination using a modified Poisson regression for binary outcomes. RESULTS: Among 645 GBM who provided a valid anal specimen (median age, 26 years; 5.9% HIV positive), 40.3% reported receiving ≥1 dose of HPV vaccine, of whom 61.8% received 3 doses. One-quarter were infected with ≥1 quadrivalent type (crude, 25.7%; RDS weighted, 24.4%). After adjustment for potential confounders, vaccinated GBM had a 27% lower anal prevalence of quadrivalent types compared with unvaccinated GBM (adjusted prevalence ratio [aPR], 0.73; 95% confidence interval [CI], 0.54-1.00). Lower prevalence ratios were found among vaccinated participants who were vaccinated >2 years before enrollment (aPR, 0.47; 95% CI, 0.25-0.86) or received their first vaccine dose at age ≤23 years (aPR, 0.64; 95% CI, 0.42-0.99). Point estimates were similar for ≥2 or 3 doses and 9-valent types. CONCLUSIONS: Human papillomavirus vaccination was associated with a lower anal prevalence of vaccine-preventable HPV types among young, sexually active GBM. Findings will help inform shared decision making around HPV vaccination for GBM and their healthcare providers.

Association of Serum 25-Hydroxyvitamin D With Prevalence, Incidence, and Clearance of Vaginal HPV Infection in Young Women.

BACKGROUND: We assessed the association between serum 25-hydroxyvitamin D levels and genital human papillomavirus (HPV) prevalence, incidence, and clearance among female participants in the HPV Infection and Transmission among Couples through Heterosexual activity (HITCH) Cohort Study. METHODS: We genotyped HPV DNA in vaginal samples and quantified baseline serum 25-hydroxyvitamin D levels using Roche's Linear Array and Total vitamin D assay, respectively. We used logistic and Cox proportional hazards models, respectively, to estimate adjusted odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: There was no association between vitamin D levels (every 10-ng/mL increase) at baseline and HPV prevalence (OR, 0.88; 95% CI, .73-1.03) or incidence (HR, 0.88; 95% CI, .73-1.06), but we observed a modest negative association with HPV clearance (HR, 0.76; 95% CI, .60-.96). Vitamin D levels <30 ng/mL, compared with those ≥30 ng/mL, were not associated with HPV prevalence (OR, 0.98; 95% CI, .57-1.69) or incidence (HR, .87; 95% CI, .50-1.43), but they were associated with a marginally significant increased clearance (OR, 2.14; 95% CI, .99-4.64). We observed consistent results with restricted cubic spline modeling of vitamin D levels and clinically defined categories. HPV type-specific analyses accounting for multiple HPV infections per participant showed no association between vitamin D levels and all study outcomes. CONCLUSIONS: This study provided no evidence of an association between low vitamin D levels and increased HPV prevalence, acquisition, or clearance.

Development and evaluation of a new non-competitive Luminex immunoassay detecting antibodies against human papillomavirus types 6, 11, 16 and 18.

Serum antibody levels can be used to measure the humoral immune response against human papillomaviruses (HPV). We developed and validated a rapid, technically simple and relatively inexpensive multiplex non-competitive Luminex-based immunoassay (ncLIA) to measure total IgG antibody levels against four HPV types. For the assay's solid phase, virus-like particles (VLPs) of HPV6, 11, 16 and 18 were bound to heparin-coated beads. HPV serum antibody levels binding to the VLPs were quantified using a phycoerithrin-conjugated secondary polyclonal donkey anti-human IgG antibody. Standardization and validation of the ncLIA were performed using 96 paired serum and genital samples from participants in the HITCH cohort study, including young women (aged 18-24 years) and their male sexual partners (aged 18+) in Montreal, Canada. Results from the ncLIA were compared to a validated Luminex immunoassay from PPD laboratories using Pearson's correlation coefficients, receiver operating characteristic curves and logistic regression. Our assay had good inter- and intra-assay variability. The correlation of serum antibody levels between the ncLIA and validation assay was highest for HPV16 and HPV11 (r=0.90), followed by HPV6 (r=0.86) and HPV18 (r=0.67). The ncLIA was better able to predict HPV DNA positivity in genital samples than the validation assay for HPV16 [area under the curve (AUC) 0.65 versus 0.52, P=0.001] and HPV18 [AUC 0.71 versus 0.57, P=0.024]. AUCs for HPV6 and HPV11 were similar between the two assays (0.70 versus 0.71, P=0.59, and 0.88 versus 0.96, P=0.08, respectively). The developed ncLIA is useful for measuring total IgG antibody response following natural infection or vaccination against four HPV VLPs included in the quadrivalent vaccine.

Assessment of the possible inhibitory effect of carrageenan in human papillomavirus DNA testing by polymerase chain reaction amplification.

We assessed carrageenan's potential to inhibit human papillomavirus (HPV) DNA extraction and amplification in vaginal swab samples collected in a trial, assessing the efficacy of a carrageenan-based gel against HPV infections. Experiment #1 consisted of adding gel (carrageenan-containing or placebo) to swabs and comparing HPV DNA detection by polymerase chain reaction (PCR) to unmanipulated samples collected from the same participants. For Experiments #2 and #3, we tested vaginal samples for inhibition by addition of an internal control and amplification by real-time PCR. Experiment #4 investigated carrageenan's interference with the extraction process by assessing HPV45 detectability in undiluted and diluted HPV45 positive samples (n = 3) with carrageenan versus no gel. In Experiment #1, there was a loss of HPV positivity with the addition of carrageenan (n = 9), but none with placebo gel (n = 5). In Experiments #2 and #3, the absence of the amplified product was observed in samples from the carrageenan arm: 3.3% (1/30) and 0.5% (1/199) of samples. In Experiment #4, HPV45 was not detected in undiluted carrageenan-containing samples, but after 1/50 dilution, the same HPV45 copy number was detected. Carrageenan does not affect the DNA extraction process, and inhibition of HPV DNA amplification by carrageenan occurs infrequently.

Comparison of SARS-CoV-2 detection with the Cobas® 6800/8800 system on gargle samples using two sample processing methods with combined oropharyngeal/nasopharyngeal swab.

BACKGROUND: Gargle samples have been proposed as a noninvasive method for detection of SARS-CoV-2 RNA. The clinical performance of gargle specimens diluted in Cobas® PCR Media and in Cobas® Omni Lysis Reagent was compared to oropharyngeal/nasopharyngeal swab (ONPS) for the detection of SARS-CoV-2 RNA. STUDY DESIGN: Participants were recruited prospectively in two COVID-19 screening clinics. In addition to the ONPS, participants gargled with 5 ml of natural spring water split in the laboratory as follows: 1 ml was added to 4.3 ml of polymerase chain reaction (PCR) media and 400 µl was added to 200 µl of lysis buffer. Testing was performed with the Cobas® SARS-CoV-2 test on the Cobas® 6800 or 8800 platforms. RESULTS: Overall, 134/647 (20.7%) participants were considered infected because the ONPS or at least one gargle test was positive. ONPS had, respectively, a sensitivity of 96.3% (95% confidence interval [CI]: 91.3-98.5); both gargle processing methods were slightly less but equally sensitive (90.3% [95% CI: 83.9-94.3]). When ONPS and gargle specimens were both positive, the mean cycle threshold (Ct ) was significantly higher for gargles, suggesting lower viral loads. CONCLUSION: Gargle specimens directly added in PCR Media provide a similar clinical sensitivity to chemical lysis, both having a slightly, not significantly, lower sensitivity to ONPS.