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Abstract Background We examined differences in incident HIV infection between newly-arrived Asian-born and other men who have sex with men (MSM) after the introduction of universal HIV treatment guidelines in 2015 and pre-exposure prophylaxis in 2016. Methods Clinical, demographic, laboratory and behavioural data on MSM presenting for HIV testing at the Melbourne Sexual Health Centre from July 2013 to June 2017 were extracted. We compared the proportion of newly-arrived (four years or less in Australia), Asian-born and other MSM tested each year who were diagnosed with incident HIV infection (negative test within one year or diagnosis with indeterminate or negative Western Blot). Results We analysed 35,743 testing episodes in 12,180 MSM, including 2781 testing episodes in 1047 newly-arrived Asian-born MSM. The proportion of other MSM tested each year who were diagnosed with incident HIV infection fell from 0.83% in 2014 to 0.38% in 2017 (p = .001), but did not fall in newly-arrived Asian-born MSM (from 1.18% in 2014 to 1.56% in 2017, p = .76). In the multivariate logistic regression, in 2016/2017 but not in 2014/2015, being newly-arrived Asian-born was associated with an increased odds of diagnosis of incident HIV infection (aOR 3.29, 95%CI 1.82–5.94, p

Syphilis, caused by Treponema pallidum subsp. pallidum (TPA), remains an important public health problem with an increasing worldwide prevalence. Despite recent advances in in vitro cultivation, genetic variability of this pathogen during infection is poorly understood. Here, we present contemporary and geographically diverse complete treponemal genome sequences isolated directly from patients using a methyl-directed enrichment prior to sequencing. This approach reveals that approximately 50% of the genetic diversity found in TPA is driven by inter- and/or intra-strain recombination events, particularly in strains belonging to one of the defined genetic groups of syphilis treponemes: Nichols-like strains. Recombinant loci were found to encode putative outer-membrane proteins and the recombination variability was almost exclusively found in regions predicted to be at the host-pathogen interface. Genetic recombination has been considered to be a rare event in treponemes, yet our study unexpectedly showed that it occurs at a significant level and may have important impacts in the biology of this pathogen, especially as these events occur primarily in the outer membrane proteins. This study reveals the existence of strains with different repertoires of surface-exposed antigens circulating in the current human population, which should be taken into account during syphilis vaccine development.

INTRODUCTION:The aim of this study was to determine the risk factors for HIV infection and the incidence in men who have sex with men (MSM). It is important to identify subgroups of MSM in which preventive interventions such as pre-exposure prophylaxis (PrEP) offered at the time of their last negative test would be considered cost-effective. METHODS:We conducted a retrospective cohort study of MSM attending Melbourne Sexual Health Centre (MSHC) during 2007-2013 with at least two HIV tests within 12 months of each other. Demographic characteristics, sexual and other behaviours, and bacterial sexually transmitted infection (STI) diagnoses were extracted from the date of the last negative HIV test. HIV incidence rate (IR) per 100 person-years for each risk factor was calculated. RESULTS:Of the 13907 MSM who attended MSHC, 5256 MSM had at least two HIV tests and were eligible, contributing 6391 person-years follow-up. 81 new HIV diagnoses were identified within 12 months of an HIV negative test with an incidence of 1.3 (95% CI: 1.0-1.6) per 100 person-years. Significant associations with subsequent HIV infection were: rectal gonorrhea (HIV IR: 3.4 95% CI: 2.1-5.2), rectal chlamydia (HIV IR: 2.6 95% CI: 1.7-3.7), inconsistent condom use (HIV IR: 2.1 95% CI: 1.6-2.7), use of post-exposure prophylaxis (HIV IR: 2.3 95% CI: 1.7-3.1), and injecting drug use (HIV IR: 8.5 95% CI: 3.4-17.5). CONCLUSION:The incidence of HIV was above 2.0% in subgroups of MSM with specific characteristics at the last HIV negative test. PrEP is considered cost effective at this incidence and could potentially be used along with other preventive interventions for these individuals in more than half of the population.

The frequency of testing sex workers for sexually transmitted infections (STIs) in Victoria, Australia, was changed from monthly to quarterly on 6 October 2012. Our aim was to determine the impact of this change to the clients seen at the Melbourne Sexual Health Centre (MHSC).Computerised medical records of all clients attending at MHSC from 7 October 2011 to 7 October 2013 were analysed.Comparing between the monthly and quarterly testing periods, the number of consultations at MSHC with female sex workers (FSW) halved from 6146 to 3453 (p

BACKGROUND: Syphilis point-of-care tests may reduce morbidity and ongoing transmission by increasing the proportion of people rapidly treated. Syphilis stage and co-infection with HIV may influence test performance. We evaluated four commercially available syphilis point-of-care devices in a head-to-head comparison using sera from laboratories in Australia. METHODS: Point-of-care tests were evaluated using sera stored at Sydney and Melbourne laboratories. Sensitivity and specificity were calculated by standard methods, comparing point-of-care results to treponemal immunoassay (IA) reference test results. Additional analyses by clinical syphilis stage, HIV status, and non-treponemal antibody titre were performed. Non-overlapping 95% confidence intervals (CI) were considered statistically significant differences in estimates. RESULTS: In total 1203 specimens were tested (736 IA-reactive, 467 IA-nonreactive). Point-of-care test sensitivities were: Determine 97.3%(95%CI:95.8-98.3), Onsite 92.5%(90.3-94.3), DPP 89.8%(87.3-91.9) and Bioline 87.8%(85.1-90.0). Specificities were: Determine 96.4%(94.1-97.8), Onsite 92.5%(90.3-94.3), DPP 98.3%(96.5-99.2), and Bioline 98.5%(96.8-99.3). Sensitivity of the Determine test was 100% for primary and 100% for secondary syphilis. The three other tests had reduced sensitivity among primary (80.4-90.2%) compared to secondary syphilis (94.3-98.6%). No significant differences in sensitivity were observed by HIV status. Test sensitivities were significantly higher among high-RPR titre (RPR ≥ 8) (range: 94.6-99.5%) than RPR non-reactive infections (range: 76.3-92.9%). CONCLUSIONS: The Determine test had the highest sensitivity overall. All tests were most sensitive among high-RPR titre infections. Point-of-care tests have a role in syphilis control programs however in developed countries with established laboratory infrastructures, the lower sensitivities of some tests observed in primary syphilis suggest these would need to be supplemented with additional tests among populations where syphilis incidence is high to avoid missing early syphilis cases.

The article discusses a study on whether rectal gonorrhoea can be used as a lead indicator of trends in HIV diagnosis in men who have sex with men. It notes that gonorrhoea is prevalent among males in Australia and cites an increasing diagnoses of rectal gonorrhoea (RG) with the great majority of infections occurring among men who have sex with men (MSM). RG and HIV tests were conducted during the study period with the highest annual proportion positive was in 2009 for HIV and 2006 for RG. It suggests the need for further research at an individual level to test the surveillance hypothesis presented in the study since establishing a temporal relationship between RG and HIV diagnoses can inform clinical and public health practice.