Grant: Travel Awards - Institute Community Support

The female genital tract contains protective bacteria called Lactobacilli whose composition changes over time due to several factors resulting in a condition called bacterial vaginosis. This condition creates a suitable environment whereby the high-risk human papilloma virus (HPV) can easily infect the women leading to development of genital cancers. We sought to understand how sexual behavior impacts the changes of genital bacteria i.e. the microbiome, and how this increases the risk of high-risk HPV. We carried out laboratory tests to test the microbiome types of 256 pilot samples from the HITCH cohort consisting of 18-24-year-old female university students and their male partners in Montréal, Canada (2005-2011). We used statistical analysis to investigate the associations between the microbiome, sex and behaviors associated with sex, and occurrence of high-risk HPV. The average age of the women was 21, while men was 22. Most men had Corynebacterium tuberculostearicum (34%). Most female participants had Lactobacillus dominant microbiome 70% while only 29% had species that cause bacterial vaginosis. A total of 36% of the participants were infected with cancer-causing HPV types, out of those only 15% were infected with HPV 16 which is strongly associated with genital cancers. We did not find any difference in similarity of microbiome between couples (mean:0.83) or random individuals (mean:0.78). We did not find any association between microbiome scores at individual level, or the microbiome clusters with increased risk acquiring HPV 16 in both males and females. In this analysis we did not identify any similarity between the microbiome of sex partners or their association with HPV. Ongoing longitudinal analysis involving the whole cohort hold promise for uncovering insights to fill in the gap in knowledge of how sexual behavior and microbiome between partners impacts transmission of HPV.