Longitudinal assessment of nonavalent vaccine HPV types in a sample of sexually active African American women from ten U.S. Cities

BACKGROUND

Chronic infection with high-risk human papillomavirus is a necessary cause for cervical carcinogenesis. This study examined prevalence of nonavalent vaccine preventable HPV types over four months among sexually active women in the United States.

METHODS

This sub-study obtained meta-data for 80 of the 1,365 women (18-25 years), enrolled in the BRAVO study, a randomized, open-label trial of home screening and treatment of asymptomatic bacterial vaginosis at high-risk for sexually transmitted infections conducted between 2008 and 2013. Participants were randomized to treatment or standard-of-care, and followed every 2-months for 12 months. Stored vaginal swabs from the first three visits were tested for the nine vaccine preventable HPV types using quantitative PCR. Prevalence and associated 95% confidence intervals for the HPV types were assessed using R (version 3.6.1).

RESULTS

The average age of the participants was 21.5 (SD ± 2.11) years, with 60% having ever been pregnant and all were African-American. Majority (71%) reported ≥ two sex partners in the prior year with 89% having unprotected vaginal sex and 45% having a new sex partner in the prior year. About 30% had ≥ one of the nine nonavalent vaccine HPV types at all three time points over a period of four months, 15% at two of any three visits, 19% at one of the three visits and 36% were negative for all nine vaccine HPV types at all time points. The most frequently detected HPV vaccine types were 52, 58, 16, and 18. The prevalence of any vaccine HPV types, and high-risk HPV types was 63.8% and 58.8%, respectively.

CONCLUSIONS

Our findings suggest that HPV vaccination which is currently recommended for all unvaccinated persons through age 26 years, is likely to be more beneficial than previously thought as nonavalent HPV vaccine was not available during the time these data were collected.

Composition of the Vaginal Microbiome Associated with High Risk HPV Infection and Increased Risk for Cervical Cancer

Persistent high-risk Human papillomavirus (HPV) is a necessary but not sufficient cause for development of cervical cancer. Changes in the vaginal microbiota including reduction of Lactobacillus and increased microbial diversity may facilitate HPV infection and persistence as well as the pathogenesis of cervical cancer. Our objective was to characterize the vaginal microbiota among women with and without persistent HPV infection with HPV 6, 11, 16, 18, 31, 33, 45, 52, 58 in a cohort of young U.S. women. Methods: This analysis used data from a longitudinal study of 1365 women followed for 12 months every two months apart from six locations across the US. HPV genotyping was performed using quantitative PCR using TaqMan probes in a customized plate (ThermoFisher Scientific). Bacterial communities were profiled by 16S rRNA gene sequences from the V3-V4 region using high-throughput pyrosequencing. Persistence was defined by examining for HPV presence in two consecutive visits. Results: Participants included 80 African-American women tested at 3 consecutive time-points. The mean age of participants was 21.4 years. About 43.7% (95% CI: 32.7%–55.3%) had persistent HPV infection, 20% (11.9%–30.4%) were able to clear the infection, and 36.2% (25.8%–47.8%) were consistently negative for HPV infection at all three time points. Atopobium and Peptoniphilus were significantly more abundant in women who were HPV negative suggesting possible protective effects. Prevotella bivia was enriched among women with persistent HPV. Conclusion: Based on these data, we can hypothesize that Prevotella richness is significantly associated with HPV persistence, suggesting a possible role in chronic HPV infection and development of cervical cancer.

Detection of mutagenic activity in textiles with Salmonella typhimurium

A hundred and ninety-six textile samples were tested in a modified version of the Salmonella/microsome assay for release of mutagenic contaminants. As heat sterilization of the samples can result in reduction of mutagenic activity, tests were performed with streptomycin resistant derivatives of Salmonella tester strains TA98 and TA100. Textile samples were preincubated in buffered saline (PBS), DMSO or ethanol. Subsequently, the fabrics were placed on streptomycin supplemented selective agar plates. In total, 18 samples (9.2%) exerted mutagenic activity. DMSO was the most effective solvent (15 positives) followed by ethanol (9 positive samples) and PBS (7 positives). Most fabrics (16) caused mutagenic effects only upon metabolic activation with liver S9 mix. Chemical analysis indicates that the positive results obtained with PBS are not due to release of histidine or formaldehyde. Three directly active samples gave negative results in strain TA98NR which is devoid of classical nitroreductase. With one exception all other textiles were negative in strain TA98/1,8-DNP6 (which lacks O-acetyltransferase). These findings indicate that nitroaromatics and amines might be responsible for the mutagenic effects of the textiles.