Investigating oral human papillomavirus co-infection with Neisseria gonorrhoeae and Chlamydia trachomatis.

Compared to cervical cancer, little is known about human papillomavirus (HPV)-driven oropharyngeal cancer and their cofactors. Here, we investigated potential associations between Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) with oral HPV and HPV persistence, which are known cofactors in cervical carcinogenesis, and also play a role in HPV-driven oropharyngeal cancer. Saliva samples (n = 547) from 312 people were tested for CT and NG and whom had previously been tested for oral HPV infection in a longitudinal study. Eight participants were positive for CT (2.6%) and one for NG (0.3%). Six of these nine participants were also positive for oral HPV in at least one of their samples. We found no significant associations between HPV, CT, or NG infection in the saliva samples analyzed. These preliminary data suggest CT and NG have little influence on oral HPV-positivity and persistence in a general population. However, larger studies focusing on 'at risk' population cohorts are necessary to assess potential associations between oral sexually transmissible infections and oral HPV infections, and their outcomes.

Oral human papillomavirus (HPV) infection and HPV vaccination in an Australian cohort.

Human papillomavirus (HPV)-related oropharyngeal cancer (OPC) is increasing in incidence, yet very little is known about oral HPV infection in the general population. In this Australian-based study we assess oral HPV prevalence according to HPV vaccination status. Participants of the Oral Diversity Study were Australian residents, aged 18 to 70 years, who filled out a questionnaire about lifestyle and sexual behaviour, and donated a saliva sample in 2020 to 2021. We obtained permission to access HPV vaccination status through record linkage with the Australian Immunisation Register. Saliva samples were DNA extracted, DNA quality checked and analysed for HPV. We recruited 1023 participants to the Oral Diversity Study. Nine hundred twenty-one returned a saliva sample for analysis, 911 passed the DNA quality check and were included in the study. The oral HPV prevalence was 7.2%, and was strongly associated with sexual behaviours. We identified 27 different HPV types; 53% of participants carried high-risk HPV types, with no difference between the vaccinated and the unvaccinated groups (53% both, P = .979). Two hundred thirty participants (26%) were HPV vaccinated. The oral prevalence of the nine HPV types included in the nonavalent HPV vaccine was significantly lower in the vaccinated participants compared to the unvaccinated (0.9% vs 3.4%; P = .022). These findings suggest that a sizeable minority of Australian residents harbour oral HPV infections, and many of these are high-risk subtypes. We found some evidence that HPV vaccination resulted in lower prevalence of oral HPV infections of vaccine-specific types. Larger surveys are required to confirm these findings.

Self-reported HPV vaccination and vaccination record linkage in the Australian Oral Diversity Study.

PURPOSE: Australia has a school-based human papillomavirus (HPV) vaccination scheme that was implemented for girls in 2007 and for boys in 2013. HPV vaccination status is important for many studies into HPV infection. Here we wanted to estimate the validity of self-reported HPV vaccination status by comparing self-report to data from the national vaccination register. METHODS: Australian residents aged 18-70 years were recruited for the Oral Diversity Study from October 2020 to November 2021. Participants were asked to provide consent for record linkage to the Australian Immunisation Register (AIR). They were also asked to fill out a questionnaire about HPV vaccination, lifestyle, and sexual behavior. RESULTS: 1,023 participants were recruited, permission was received from 911 participants for HPV vaccination record linkage, and 850 self-reported vaccination and were part of the validity analysis. Of those 233 (26%) were confirmed to be HPV vaccinated. Ninety-one percent of the vaccinated were females (n = 212), 19 males and two non-binary. The highest HPV vaccine uptake was seen in the youngest age group (18-29 years; 80%), followed by 66% in 30-39 year olds, 2% in 40-49 year olds and then dropped significantly to 0.7% for people 50-70 years old. The sensitivity of self-report was 99.0%, and the specificity 94.5%, and the positive predictive value was 85.7% and the negative predictive value 99.7%. CONCLUSION: We found that the correlation between self-reported Gardasil® vaccination and the AIR records were very good, with high sensitivity and specificity.

Sexual debut and association with oral human papillomavirus infection, persistence and oropharyngeal cancer-An analysis of two Australian cohorts.

Oropharyngeal cancer is increasingly caused by human papillomavirus (HPV), and this increase is believed to be caused by changing sexual behaviour. It has been hypothesised that an immune response to HPV through sexual intercourse is much stronger than an immune response elicited from oral sex. Therefore, people who have their debut of oral sex before or at the same time as sexual intercourse would have a weaker immune response to HPV and hence be more likely to develop a persistent oral HPV infection and oropharyngeal cancer. Drake et al (Cancer. 2021;127[7]:1029-1038) found some evidence that supported this hypothesis. We have reanalysed two of our Australian cohorts with similar data in order to provide a perspective of Drake and colleagues' publication, as sexual behaviour varies depending on culture and geographical location. We found that engaging in oral sex (OR 4.46, 95% CI [1.88-10.62]) and being younger than 20 years at oral sex debut (OR 9.46, 95% CI [3.53-25.31]) were both very strong risk factors for oropharyngeal cancer. Participants in the general population cohort who had their sexual intercourse debut before the age of 18 were more likely to be oral HPV positive (OR 2.69, 95% CI [1.50-4.83]). Oral sex debut before sexual intercourse debut was quite uncommon in our two Australian cohorts. However, timing of or sexual debuts may further add to risks of oropharyngeal cancer, and future studies should be designed to investigate timing and order of sexual debuts to help clarify the roles of these potential causal factors.

Associations of keratinocyte cancers with snp variants in the sonic hedgehog pathway.

BACKGROUND: Sonic Hedgehog (SHH) pathway dysregulation is implicated in basal cell carcinoma (BCC) development. To evaluate the possible wider role of SHH gene variants in skin carcinogenesis, we assessed associations of genes in the SHH pathway with lifetime development of any keratinocyte cancer (KC), and with developing either BCCs or squamous cell carcinomas (SCCs) exclusively, in a 25-year prospective, population-based study of 1,621 Australians. METHODS: We genotyped 795 unrelated adults with available blood samples: 311 cases with any KC (186 developing BCCs-only, 55 SCCs-only, 70 BCCs and SCCs) and 484 controls. We compared allele frequencies of 158 independent SNPs across 43 SHH genes between cases and controls, and performed a gene-based analysis. RESULTS: We found associations between SNP rs4848627 (GLI2) (related to DNA synthesis in keratinocytes) and development of any KC (OR = 1.53; 95% CI = 1.06-2.13, P < 0.01) and SCCs exclusively (OR = 2.12; 95%CI = 1.39-3.23, P < 0.01). SNP rs3217882 located in CCND2 was associated with exclusive BCC development (OR = 1.43, CI = 1.12-1.82, P < 0.01). The gene-based analysis suggested an association of PRKACG (protein kinase cAMP-activated catalytic subunit gamma) with any KC (P = 0.013). CONCLUSION: We conclude that variants located in genes in the SHH pathway may are involved in SCC as well as BCC development.

Dark Green Leafy Vegetable Intake, MTHFR Genotype, and Risk of Cutaneous Squamous Cell Carcinoma.

BACKGROUND: Evidence suggests that consumption of dark green leafy vegetables may influence the decrease in the risk of cutaneous squamous cell carcinoma (SCC). Dark green leafy vegetables contain folate as a main component among other nutrients; thus, we hypothesised that their possible observed protective effect on SCC, observed in previous studies, would be more evident in persons with specific genotypes related to folate metabolism. METHODS: Genotyping of methylenetetrahydrofolate reductase (MTHFR) gene variants rs1801133 (C677T) and rs1801131 (A1298C) was carried out for 1,128 participants in an Australian community-based longitudinal study of skin cancer. Dietary intakes were assessed through repeated Food Frequency Questionnaires (1992-1996), and all incident skin cancers were recorded in 1992-2007 and histologically confirmed. We assessed associations between intake of dark green leafy vegetables and SCC development in strata defined by genotype, by calculating relative risks (RRs) with 95% confidence intervals (CIs) using generalised linear models with negative binomial distribution and person-years of follow-up as offset. RESULTS: High versus low intake of dark green leafy vegetables was associated with a lower risk of SCC tumours in carriers of the C677T variant allele (RR = 0.42, 95% CI = 0.23-0.75), and within wild-type A1298C homozygotes (RR = 0.43, 95% CI = 0.22-0.85). CONCLUSION: The protective effect of dark green leafy vegetables on cutaneous SCC may be genotype-dependent. Folate metabolism-related gene polymorphisms should be considered when assessing the relation of green leafy vegetables to cancer risk.

An update on Heck's disease-a systematic review.

BACKGROUND: Previous research has suggested an ethnic association of Heck's disease with a prominent genetic and familial inheritance pattern, but no systematic review has been reported, which has collected all the evidence in one paper. The aim was estimation of the updated age estimates and gender predilection of this disease and also questioning its proposed link to ethnic and geographical factors. METHODS: Heck's disease from 1966 until present are tabulated, including various descriptive characteristics. After removal of duplicates and adhering to all the inclusion criteria, we shortlisted 95 case reports. The quality assessment of all included studies has been done following STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) guidelines. RESULTS: We found an age range of 3-92 years (mean: 23.1 years) with a male to female ratio of 3:4. Geographical distribution revealed one of the main findings of this study, which was an increased incidence of Heck's disease in the European region. CONCLUSIONS: As already observed and established, there is a much greater prevalence of this disease in the indigenous populations of the world and more research should be encouraged to understand the correct transmission and pattern of spread of this disease.

Natural history of oral HPV infection: Longitudinal analyses in prospective cohorts from Australia.

Oral infection with human papillomavirus (HPV) is likely to underpin the rapidly rising incidence of oropharyngeal squamous cell carcinoma; however, there are few data describing the natural history of oral HPV infection. We recruited 704 participants aged 20 to 70 years from worksites, universities and primary care practices in Brisbane, Australia. Participants completed questionnaires at baseline, 12 and 24 months and donate four saliva samples at baseline, 6, 12 and 24 months for HPV polymerase chain reaction testing and typing. We estimated the prevalence of oral HPV infection at baseline, incidence of new infections among those HPV-negative at baseline, clearance rate and persistent infections. At baseline, 10.7% of participants had oral HPV infections from 26 different HPV types. Sexual behaviours were associated with oral HPV infection, including more partners for passionate kissing (29 or more; odds ratio [OR] 3.4, 95% confidence interval [CI] 1.5-8.0), and giving and receiving oral sex (16 or more; OR 5.4, 95% CI 1.6-17.7 and OR 5.6, 95% CI 1.6-18.7, respectively). Of 343 participants, HPV-free at baseline and with subsequent saliva samples, 87 (25%) acquired new infections over the 24 months. Sixty-eight of 87 people included in the clearance analysis (78%) cleared their oral HPV infections. Clearance was associated with being a nonsmoker (OR 12.7, 95% CI 1.3-122.8), and no previous diagnosis of a sexually transmitted infection (OR 6.2, 95% CI 2.0-19.9). New oral infections with HPV in this sample were not rare. Although most infections were cleared, clearance was not universal suggesting a reservoir of infection exists that might predispose to oropharyngeal carcinogenesis.

Host genetic polymorphisms associated with beta human papillomavirus seropositivity.

Human papillomaviruses (HPVs) cause superficial epidermal infections and are only cleared if they trigger an immunological response. We analysed SNPs that had previously been investigated for association with HPV infection to determine whether they play a role in the serological response to cutaneous beta-HPVs in an Australian population. Serum samples from 1,142 participants were analysed for seropositivity against the L1 protein of 21 beta-HPV types. Associations between seropositivity to beta-HPV types and the SNPs rs9264942 (HLA-C; HPV-9, p = 0.022, HPV-15, p = 0.043 and HPV-17, p = 0.004), rs12449858 (EVER1; HPV-23, p = 0.029), and rs2981451 (FGFR2; HPV-22, p = 0.049) were identified. We found that certain SNPs could be involved in the serological response to beta-HPVs.

A systematic review and meta-analysis of the prevalence of human papillomavirus infection in Indigenous populations - A Global Picture.

BACKGROUND AND AIM: Recent trends have shown a decline in the rates of human papillomavirus (HPV)-associated cervical cancer in the vaccinated population but there has been a spike in the HPV-associated oropharyngeal, anal and penile cancers in the majority of the unvaccinated population which are young and middle-aged males. Indigenous populations at an international level carry a disproportionate burden of most diseases. The aim of this meta-analysis was to ascertain the worldwide prevalence of HPV infection in Indigenous populations stratified by sex and site and to document the most commonly reported HPV types. METHODS: Published articles on HPV infection in Indigenous populations from PubMed, Scopus, EMBASE and Web of Science were systematically searched from inception until 23 December 2019. RESULTS: A total of 41 studies were included in the final analysis. The pooled worldwide prevalence of HPV infection (for both oral and genital sites, both males and females) in Indigenous populations was 34.2% (95% CI: 28.9%-39.8%). Subgroup analysis (geographical) showed that the pooled prevalence for African Indigenous, American Indigenous and Asian-Oceanic Indigenous populations were 33.0% (95% CI: 12.8%-57.1%), 33.0% (95% CI: 27.4%-38.9%) and 33.3% (95% CI: 0.17.5%-51.3%), respectively. CONCLUSION: There are not enough data on the burden of the infection carried by males especially with respect to highly suspicious sites like oropharynx. Also, we conclude an overall high prevalence of HPV infection in the Indigenous populations and increasing their susceptibility to benign and malignant manifestations of HPV.

How many cancer cases and deaths are potentially preventable? Estimates for Australia in 2013.

Cancer is a leading cause of disease burden in Australia, particularly fatal burden, accounting for an estimated thirty percent of deaths. Many cancers develop because of exposure to lifestyle and environmental factors that are potentially modifiable. We aimed to quantify the proportions and numbers of cancer deaths and cases in Australia in 2013 attributable to 20 modifiable factors in eight broad groupings that are established causes of cancer, namely: tobacco smoke (smoking and second-hand), dietary factors (low intake of fruit, non-starchy vegetables and dietary fibre; and high intake of red and processed meat), overweight/obesity, alcohol, physical inactivity, solar ultraviolet radiation, infections (seven agents), and reproductive factors (lack of breastfeeding, menopausal hormone therapy use, combined oral contraceptive use). We estimated population attributable fractions (PAF) using standard formulae incorporating exposure prevalence and relative risk data. Of all cancer deaths in Australia in 2013, approximately 38% overall (males 41%, females 34%) could be attributed to the factors assessed; the corresponding PAF for cancer cases was 33% (males 34%, females 32%). Tobacco smoke was the leading cause of cancer deaths and cases, with PAFs of 23 and 13%, respectively, followed by dietary factors (5% deaths/5% cases), overweight/obesity (5%/4%) and infections (5%/3%). Cancer sites with the highest numbers of potentially preventable deaths/cases were lung (n = 6,776/9,272), colorectum (n = 1,974/7,380) and cutaneous melanoma (n = 1,390/7,918). We estimate that about 16,700 cancer deaths and 41,200 cancer cases could be prevented in Australia each year if people's exposures to 20 causal factors were aligned with levels recommended to minimise cancer risk.

Sexual behaviour, HPV status and p16INK4a expression in oropharyngeal and oral cavity squamous cell carcinomas: a case-case comparison study.

A significant proportion of mucosal squamous cell carcinomas of the head and neck (HNSCC; particularly of the oropharynx) are directly attributable to the human papillomavirus (HPV). The increase in the incidence of HPV-related tumours has been postulated to be due to changing sexual practices in the community. We analysed 136 formalin-fixed paraffin-embedded squamous cell carcinomas from the oral cavity (n=40) and oropharynx (n=96) recruited from the Princess Alexandra Hospital (Brisbane, Australia). Samples were analysed for the presence of HPV DNA using a combination of mucosal HPV general primer GP+ PCR and sequencing; p16INK4a expression was assessed by immunohistochemistry. Each patient completed a questionnaire detailing their lifestyle factors, such as tobacco smoking and alcohol consumption, marital status, and sexual behaviour and history. The HPV DNA prevalence was 5 % in the oral cavity cancers and 72 % in the oropharyngeal cancers (P<0.0001). HPV-16 was the most commonly detected HPV type (found in 91 % of all HPV-positive tumours). There was a strong correlation between HPV DNA positivity and positive p16INK4a staining in oropharyngeal tumours (P<0.0001). Having an HPV-related tumour was associated with being married or having been married previously (P=0.046), an increasing number of passionate kissing partners (P=0.046), ever having given oral sex (P=0.0007) and an increasing number of oral sex partners (P=0.0015). This study found a higher prevalence of HPV in oropharyngeal compared to oral cavity tumours, with a strong association being identified between oral sex behaviours and HPV-positive tumours. Further research is needed to establish that vaccines will reduce the transmission and carriage of oropharyngeal HPV infections.

An Update on Cellular MicroRNA Expression in Human Papillomavirus-Associated Head and Neck Squamous Cell Carcinoma.

Squamous cell carcinoma of mucosal sites in the head and neck (HNSCC) is the sixth most common cause of cancer worldwide, and despite advances in conventional management, it still has significant morbidity and mortality associated with both diagnosis and treatment. Advances in our understanding of the biological mechanisms underlying this disease have demonstrated a significant difference between human papillomavirus (HPV)-associated, HPV and tobacco associated, and HPV-negative disease. It remains important to further elucidate the biologic and genetic differences between HPV-associated and tobacco-associated disease, with the aim of earlier diagnosis through screening, and advances in management including the development of novel therapeutic agents. MicroRNAs (miRNAs) are small, non-coding RNAs that function as post-transcriptional regulators of gene expression, and have effects on almost every cellular function, and have potentially important applications to diagnosis, management and prognosis in HNSCC. Establishing a cellular miRNA expression profile for HPV-associated disease may therefore have important implications for the screening and treatment of this disease. This review summarises the current findings regarding miRNA expression in mucosal HNSCC, and focuses particularly on miRNA expression in HPV-associated tumours.

Past sexual behaviors and risks of oropharyngeal squamous cell carcinoma: a case-case comparison.

The incidence of oropharyngeal squamous cell carcinomas (SCCs) is increasing and is believed to reflect changing sexual practices in recent decades. For this case-case comparative study, we collected medical and life-style information and data on sexual behavior from 478 patients treated at the head and neck clinic of a tertiary hospital in Brisbane, Australia. Patients were grouped as (i) oropharyngeal SCC (n = 96), (ii) oral cavity, larynx and hypopharynx SCC ("other HNSCCs," n = 96), (iii) other SCCs (n = 141), and (iv) other diagnoses (n = 145). We fitted multivariable logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) associated with lifestyle factors and sexual behaviors. Compared to the other three patient groups, the oropharyngeal SCC patients had overall more sexual lifetime partners (kissing, oral sex and sexual intercourse). Oropharyngeal SCC patients were significantly more likely to have ever given oral sex compared to the other three patient groups-93% of oropharyngeal SCC patients, 64% of other HNSCC patients, and 58% of patients with other SCC or other diagnoses. Oropharyngeal SCC patients were significantly more likely to have given oral sex to four or more partners when compared to patients with other HNSCC (odds ratio [OR] 11.9; 95% CI 3.5-40.1), other SCC (OR 16.6; 95% CI 5.3-52.0) or patients with other diagnoses (OR 25.2; 95% CI 7.8-81.7). The very strong associations reported here between oral sex practices and risks of oropharyngeal SCC support the hypothesis that sexually transmitted HPV infections cause some of these cancers.

Oral human papillomavirus infection incidence and clearance: a systematic review of the literature.

Subclinical oral human papillomavirus (HPV) infection that persists for decades is likely to precede an HPV-driven squamous cell carcinoma of the head and neck, but little is known about the natural history of oral HPV. We systematically reviewed and abstracted data from nine manuscripts that examined human immunodeficiency virus-negative and cancer-free subjects for oral HPV DNA to determine the pooled baseline prevalence and incidence of newly acquired oral HPV infections, and specifically for HPV-16. We also documented the clearance rate and the median time to clearance, where data existed. Of 3762 individuals, 7.5 % had an oral infection with any HPV type (1.6 % for HPV-16). Meta-regression analysis estimated the 12-month cumulative incidence to be 4.8 % (95 % confidence interval 3.2-7.3 %). The overall oral HPV clearance was reported to be 0-80 % between studies, and the median time to clearance from 6.5 to 18 months. Oral HPV-16 clearance was 43-83 %, and median time to clearance for HPV-16 was 7-22 months. Oral HPV prevalence, incidence and clearance vary considerably between published studies from different geographical regions. Further research is required to identify predictors of persistent oral HPV infection. Measurable baseline prevalence was observed in all studies, as well as non-trivial incidence of newly acquired oral HPV infections and incomplete clearance.

Variants of EVER1 and EVER2 (TMC6 and TMC8) and human papillomavirus status in patients with mucosal squamous cell carcinoma of the head and neck.

PURPOSE: There is a growing association of human papillomavirus (HPV) with some cases of mucosal squamous cell carcinoma of the head and neck (HNSCC), particularly of the oropharynx. Persistent oral HPV infection is believed to increase the likelihood of malignancy, and it is possible that host genetic factors can determine susceptibility to persistent HPV infection. Polymorphisms in the two EV genes (EVER1 and EVER2, also known as transmembrane channel protein (TMC) 6 and 8) have been identified as strong candidate genes, since a small number of critical mutations in these genes have been shown to cause profound and florid skin HPV infections, and some of them have been linked to susceptibility to cervical cancer. METHODS: We sought to determine whether there was a difference in the frequency of single nucleotide polymorphisms (SNPs) in EVER1 (rs2613516, rs12449858) and EVER2 (rs7205422, rs12452890) between HNSCC patients with HPV-positive and HPV-negative tumors, and healthy controls. We used logistic regression to analyze SNPs in 219 patients with histologically confirmed primary SCC of the oropharynx, oral cavity, hypopharynx, or larynx, and 321 healthy controls. RESULTS: We did not find any associations with the EVER1/EVER2 SNPs and HPV status or being a HNSCC case or a control. CONCLUSIONS: The present data do not provide evidence for a role of genetic variations in EVER1 or EVER2 for HPV status of mucosal HNSCC or between HNSCC patients and controls.

TGFß isoforms and receptors mRNA expression in breast tumours: prognostic value and clinical implications.

BACKGROUND: Transforming growth factor beta (TGFß) signalling is involved in both tumour suppression and tumour progression. The mRNA expression levels of the TGFß isoforms and receptors in breast tumours may have prognostic value and clinical implications. METHODS: The mRNA levels of TGFB1, TGFB2, TGFB3, TGFBR1 and TGFBR2 were analysed in primary breast tumours and adjacent normal breast tissues, and the associations with tumour characteristics and patients' overall and relapse-free survival were evaluated, using the public gene expression microarray data from The Cancer Genome Atlas (n = 520) and the Gene Expression Omnibus (four datasets) and our quantitative real-time PCR validation data (n = 71). RESULTS: Significantly higher TGFB1 and TGFB3 mRNA levels and lower TGFBR2 mRNA levels were observed in primary tumours compared with their paired normal tissues. TGFB1 mRNA expression was seemly lower in triple-negative tumours and in tumours from lymph node-negative patients. TGFB3 mRNA expression was significantly lower in estrogen receptor-negative/progesterone receptor-negative/Basal-like/Grade 3 tumours. High TGFB2, TGFB3 and TGFBR2 mRNA levels in tumours were generally associated with better prognosis for patients, especially those diagnosed with lymph node-negative diseases. High TGFBR1 mRNA levels in tumours were associated with poorer clinical outcomes for patients diagnosed with small (diameter ≤ 2 cm) tumours. CONCLUSIONS: The results indicate a reduced responsiveness of tumour cells to TGFß, a preferential up-regulation of TGFB1 in malignant tumours and a preferential up-regulation of TGFB3 in premalignant tumours. The results may not only provide prognostic value for patients but also assist in classifying tumours according to their potential responses to TGFß and selecting patients for TGFß signalling pathway targeted therapies.

Longitudinal study of seroprevalence and serostability of the human polyomaviruses JCV and BKV in organ transplant recipients.

The human polyomaviruses BKV and JCV cause mostly subclinical infections in childhood. Systemical immunosuppression after organ transplantation can lead to reactivation of persistent polyomavirus infections which may cause rejection of the transplanted organ. BKV and JCV seroprevalence and serostability was measured in 441 European solid organ transplanted recipients. Baseline samples were collected on average 24 days post-transplantation and sera were then collected over an 18 months follow-up period on up to six different time points. The overall seroprevalence at baseline for BKV was 97% with very little change over time. Prevalence for JCV was 76% at baseline and increased to 80% at the end of follow-up. BKV seroprevalence was highest in the youngest age group (100%) and decreased with increasing age (92% in the oldest age group; P < 0.0001), while JCV increased with age (69% vs. 81%; P = 0.020). Antibody reactivities for both BKV and JCV increased significantly with time (P = 0.0002 and P < 0.0001, respectively). Among the 406 patients with several samples, 94% were stably seropositive for BKV and 1% remained seronegative during the follow-up. JCV antibody stability was somewhat lower: 67% remained stably seropositive and 13% seronegative. While seroprevalence of BKV and JCV decrease and increase with age, respectively, both polyomaviruses showed significant increasing antibody reactivity over time in organ transplanted recipients at the onset of immunosuppression.

Development and validation of an HPV infection knowledge assessment scale among Aboriginal and Torres Strait Islander Peoples.

Background: An increased incidence of Human Papillomavirus (HPV) infection and its related cancers has been observed in recent years. Correct knowledge about HPV infection can lead to a significant decrease in transmission and a subsequent increase in vaccine uptake. Awareness and behavioural perception towards HPV infections are critical for improving HPV vaccination rates among Aboriginal and/or Torres Strait Islander Peoples. However, to the best of our knowledge, there has been no instrument designed to measure knowledge about HPV infection that is culturally appropriate and validated among Aboriginal and/or Torres Strait Islander People. Aim: To address this research gap, this paper aims to examine the psychometric properties of the HPV Knowledge Tool (HPV-KT) in an Indigenous population sample from South Australia. Methodology: Data from 747 Indigenous Australian Adults who participated in the 12-month follow-up of the HPV and Oropharyngeal Carcinoma in Indigenous Australians Study was utilised for this study. The psychometric properties examined included1) dimensionality and item redundancy; (2) network loadings; (3) model fit; (4) criterion validity; and (5) reliability. The network model was estimated using the Graphical Least Absolute Shrinkage and Selector Operator (GLASSO). Evaluation of the HPV-KT (10 items) dimensionality and item redundancy was conducted within the framework of Exploratory Graph Analysis (EGA). Reliability was evaluated with the McDonald's Omega (ω) coefficient. Results: After the exclusion of two items, the HPV-KT exhibited good psychometric properties for Aboriginal and/or Torres Strait Islander Peoples. The two dimensions of "General HPV Knowledge" and "Commonness of HPV" were identified. The dimension of "Commonness of HPV" displayed poor reliability, so a sum score for this subscale is not recommended (i.e. the items can still be used individually) The network model of the 7-item HPV-KT was fitted in the validation sample and model fit was adequate (x2 (7) = 17.17, p < 0.016; CFI = 0.980; TLI = 0.94; RMSEA = 0.063, 90% CI = 0.025-0.010). Furthermore, the reliability of the "General HPV Knowledge" subscale (ω = 0.76, 95% CI: 0.72-0.79), while the reliability of the "Commonness of HPV" subscale (ω = 0.58, 95% CI0.58-0.88) was poor. Conclusion: The HPV-KT was adapted for an Aboriginal and/or Torres Strait Islander population and is readily available for future use in Australia. The addition of items assessing specifications of HPV infection, natural history and behaviour will improve the reliability and usability to assess the level of accurate knowledge about HPV infection. Future studies should investigate the possibility of developing new items for the dimension 'Commonness of HPV'.

Natural History of Oral HPV Infection among Indigenous South Australians.

This study aims to describe the natural history of and identify the risk factors associated with oral human papillomavirus (HPV) infections in an Australian Indigenous cohort. A longitudinal cohort study design, with baseline (2018), 12-month, and 24-month data obtained from Indigenous Australians aged 18+ years in South Australia, was performed. Face-to-face interviews were conducted, and saliva samples for HPV testing were collected at each time point. Basic descriptive analyses were conducted to calculate prevalence, incidence, persistence, clearance, and incidence proportions of any HPV infection. Multivariable logistic regression analyses with adjusted prevalence ratios (PRs) were conducted to identify risk factors associated with oral HPV infection. Among 993 participants with valid saliva samples, 44 HPV types were identified. The prevalence of infection with any oral HPV infection was 51.3%, high-risk HPV was 11%, and types implicated in Heck's disease (HPV 13 or 32) was 37.4%. The incidence, persistence, and clearance of any and high-risk HPV infections were 30.7%, 11.8% and 33.3% vs. 9.3%, 2.8%, and 9%, respectively. Our findings indicate that the prevalence, incidence, and persistence of oral HPV infection in a large sample of Indigenous Australians were high, and clearance was low. Oral sex behaviours and recreational drug use were risk factors associated with incident high-risk HPV infection.