Unpredictable soil conditions can affect the prevalence of a microbial symbiosis.

The evolution of symbiotic interactions may be affected by unpredictable conditions. However, a link between prevalence of these conditions and symbiosis has not been widely demonstrated. We test for these associations using Dictyostelium discoideum social amoebae and their bacterial endosymbionts. D. discoideum commonly hosts endosymbiotic bacteria from three taxa: Paraburkholderia, Amoebophilus and Chlamydiae. Three species of facultative Paraburkholderia endosymbionts are the best studied and give hosts the ability to carry prey bacteria through the dispersal stage to new environments. Amoebophilus and Chlamydiae are obligate endosymbiont lineages with no measurable impact on host fitness. We tested whether the frequency of both single infections and coinfections of these symbionts were associated with the unpredictability of their soil environments by using symbiont presence-absence data from D. discoideum isolates from 21 locations across the eastern United States. We found that symbiosis across all infection types, symbiosis with Amoebophilus and Chlamydiae obligate endosymbionts, and symbiosis involving coinfections were not associated with any of our measures. However, unpredictable precipitation was associated with symbiosis in two species of Paraburkholderia, suggesting a link between unpredictable conditions and symbiosis.

Hijacking host cell vesicular transport: New insights into the nutrient acquisition mechanism of Chlamydia.

Chlamydia infection is an important cause of public health diseases, and no effective vaccine is currently available. Owing to its unique intracellular lifestyle, Chlamydia requires a variety of nutrients and substrates from host cells, particularly sphingomyelin, cholesterol, iron, amino acids, and the mannose-6-phosphate receptor, which are essential for inclusion development. Here, we summarize the recent advances in Chlamydia nutrient acquisition mechanism by hijacking host cell vesicular transport, which plays an important role in chlamydial growth and development. Chlamydia obtains the components necessary to complete its intracellular developmental cycle by recruiting Rab proteins (major vesicular trafficking regulators) and Rab effector proteins to the inclusion, interfering with Rab-mediated multivesicular trafficking, reorienting the nutrition of host cells, and reconstructing the intracellular niche environment. Consequently, exploring the role of vesicular transport in nutrient acquisition offers a novel perspective on new approaches for preventing and treating Chlamydia infection.

Novel typing scheme reveals emergence and genetic diversity of Chlamydia pecorum at the local management scale across two koala populations.

To overcome shortcomings in discriminating Chlamydia pecorum strains infecting the koala (Phascolarctos cinereus) at the local level, we developed a novel genotyping scheme for this pathogen to inform koala management at a fine-scale subpopulation level. We applied this scheme to two geographically distinct koala populations in New South Wales, Australia: the Liverpool Plains and the Southern Highlands to South-west Sydney (SHSWS). Our method provides greater resolution than traditional multi-locus sequence typing, and can be used to monitor strain emergence, movement, and divergence across a range of fragmented habitats. Within the Liverpool Plains population, suspected recent introduction of a novel strain was confirmed by an absence of genetic diversity at the earliest sampling events and limited diversity at recent sampling events. Across the partially fragmented agricultural landscape of the Liverpool Plains, diversity within a widespread sequence type suggests that this degree of fragmentation may hinder but not prevent spread. In the SHSWS population, our results suggest movement of a strain from the south, where diverse strains exist, into a previously Chlamydia-free area in the north, indicating the risk of expansion towards an adjacent Chlamydia-negative koala population in South-west Sydney. In the south of the SHSWS where koala subpopulations appear segregated, we found evidence of divergent strain evolution. Our tool can be used to infer the risks of strain introduction across fragmented habitats in population management, particularly through practices such as wildlife corridor constructions and translocations.

Understanding dynamics and overlapping epidemiologies of HIV, HSV-2, chlamydia, gonorrhea, and syphilis in sexual networks of men who have sex with men.

Introduction: We aimed to investigate the overlapping epidemiologies of human immunodeficiency virus (HIV), herpes simplex virus type 2 (HSV-2), chlamydia, gonorrhea, and syphilis in sexual networks of men who have sex with men (MSM), and to explore to what extent the epidemiology of one sexually transmitted infection (STI) relates to or differs from that of another STI. Methods: An individual-based Monte Carlo simulation model was employed to simulate the concurrent transmission of STIs within diverse sexual networks of MSM. The model simulated sexual partnering, birth, death, and STI transmission within each specific sexual network. The model parameters were chosen based on the current knowledge and understanding of the natural history, transmission, and epidemiology of each considered STI. Associations were measured using the Spearman's rank correlation coefficient (SRCC) and maximal information coefficient (MIC). Results: A total of 500 sexual networks were simulated by varying the mean and variance of the number of partners for both short-term and all partnerships, degree correlation, and clustering coefficient. HSV-2 had the highest current infection prevalence across the simulations, followed by HIV, chlamydia, syphilis, and gonorrhea. Threshold and saturation effects emerged in the relationship between STIs across the simulated networks, and all STIs demonstrated moderate to strong associations. The strongest current infection prevalence association was between HIV and gonorrhea, with an SRCC of 0.84 (95% CI: 0.80-0.87) and an MIC of 0.81 (95% CI: 0.74-0.88). The weakest association was between HSV-2 and syphilis, with an SRCC of 0.54 (95% CI: 0.48-0.59) and an MIC of 0.57 (95% CI, 0.49-0.65). Gonorrhea exhibited the strongest associations with the other STIs while syphilis had the weakest associations. Across the simulated networks, proportions of the population with zero, one, two, three, four, and five concurrent STI infections were 48.6, 37.7, 11.1, 2.4, 0.3, and < 0.1%, respectively. For lifetime exposure to these infections, these proportions were 13.6, 21.0, 22.9, 24.3, 13.4, and 4.8%, respectively. Conclusion: STI epidemiologies demonstrate substantial overlap and associations, alongside nuanced differences that shape a unique pattern for each STI. Gonorrhea exhibits an "intermediate STI epidemiology," reflected by the highest average correlation coefficient with other STIs.

Management of acute sexual assault presenting to a large Australian sexual health clinic in 2012-2021: a retrospective clinical audit.

Background The incidence of sexual assault continues to rise in Australia. This study aimed to describe the nature of assault, HIV/STI positivity, and its management at a sexual health clinic. Methods We performed a chart review of 516 sexual assault cases presenting to Melbourne Sexual Health Centre between 2012 and 2021, collecting data on victim demographics, details of assault, HIV/STI testing and positivity, police involvement, and offer of counselling. Results We included 516 cases: 124 males (24.0%); 384 females (74.4%); and eight transgender (1.6%) victims. The proportion of assault cases presenting to Melbourne Sexual Health Centre increased from 0.1% (37/37,070) in 2012 to 0.2% (56/36,514) in 2021 (P trend =0.006). HIV post-exposure prophylaxis was prescribed for 64.5% (80/124) of males and 12.5% (48/384) of females. Among victims, 69.4% (358/516) were tested for HIV and no one tested positive, while 71.9% (371/516) were tested for syphilis, with 1.6% (6/371) positive. Gonorrhoea and chlamydia were tested at the oropharynx (44.8% [231/516] vs 28.7% [148/516]), genitals (83.7% [432/516] vs 92.4% [477/516]) and anorectum (35.3% [182/516] vs 35.3% [182/516]). Positivity for gonorrhoea and chlamydia were: 2.6% (6/231) vs 2.0% (3/148) at oropharynx, 1.4% (6/432) vs 2.9% (14/477) at genitals, and 5.5% (10/182) vs 7.1% (13/182) at anorectum. According to clinical records, 25.2% (130/516) of victims sought police involvement, and 71.7% (370/516) were offered counselling. Conclusions Sexual assault was an uncommon presentation at Melbourne Sexual Health Centre, with diverse circumstances surrounding assault; however, clinical documentation varied, indicating a need for a standard primary care protocol for clients presenting with acute sexual assault.

IgG exacerbates genital chlamydial pathology in females by enhancing pathogenic CD8+ T cell responses.

Chlamydia trachomatis infections are an important sexually transmitted infection that can lead to inflammation, scarring and hydrosalpinx/infertility. However, infections are commonly clinically asymptomatic and do not receive treatment. The underlying cause of asymptomatic immunopathology remains unknown. Here, we demonstrate that IgG produced during male infection enhanced the incidence of immunopathology and infertility in females. Human endocervical cells expressing the neonatal Fc Receptor (FcRn) increased translocation of human IgG-opsonized C. trachomatis. Using total IgG purified from infected male mice, we opsonized C. muridarum and then infected female mice, mimicking sexual transmission. Following infection, IgG-opsonized Chlamydia was found to transcytose the epithelial barrier in the uterus, where it was phagocytosed by antigen-presenting cells (APCs) and trafficked to the draining lymph nodes. APCs then expanded both CD4+ and CD8+ T cell populations and caused significantly more infertility in female mice infected with non-opsonized Chlamydia. Enhanced phagocytosis of IgG-opsonized Chlamydia significantly increased pro-inflammatory signalling and T cell proliferation. As IgG is transcytosed by FcRn, we utilized FcRn-/- mice and observed that shedding kinetics of Chlamydia were only affected in FcRn-/- mice infected with IgG-opsonized Chlamydia. Depletion of CD8+ T cells in FcRn-/- mice lead to a significant reduction in the incidence of infertility. Taken together, these data demonstrate that IgG seroconversion during male infection can amplify female immunopathology, dependent on FcRn transcytosis, APC differentiation and enhanced CD8 T cell responses.

A novel multi-variate immunological approach, reveals immune variation associated with environmental conditions, and co-infection in the koala (Phascolarctos cinereus).

External signs of disease are frequently used as indicators of disease susceptibility. However, immune profiling can be a more effective indicator to understand how host responses to infection may be shaped by host, pathogen and environmental factors. To better inform wildlife health assessment and research directions, we investigated the utility of a novel multivariate immunophenotyping approach examining innate and adaptive immune responses in differing climatic, pathogen co-infection and demographic contexts across two koala (Phascolarctos cinereus) populations in New South Wales: the Liverpool Plains (LP), and Southern Highlands to South-west Sydney (SHSWS). Relative to the comparatively healthy SHSWS, the LP had greater and more variable innate immune gene expression (IL-1ß, IL-6), and KoRV transcription. During extreme heat and drought, koalas from the LP displayed upregulation of a stress pathway gene and reduced adaptive immune genes expression, haematocrit and plasma protein, suggesting the possibility of environmental impacts through multiple pathways. In those koalas, KoRV transcription status, Chlamydia pecorum infection loads, and visible urogenital inflammation were not associated with immune variation, suggesting that immune markers were more sensitive indicators of real-time impacts than observed disease outcomes.

Oportunidades perdidas en la detección temprana de la infección por VIH en pacientes con infecciones de transmisión sexual: un estudio de vida real / Missed opportunities in the early detection of HIV infection in patients with sexually transmitted infections: A real-life study

Introducción: Las enfermedades de transmisión sexual, como la cervicitis, la proctitis y la uretritis, se asocian a altas tasas de infección por VIH. Ante la sospecha de estas patologías, se debería solicitar una serología del VIH. Material y métodos: Estudio retrospectivo realizado durante 2018 en el Hospital Costa del Sol (Marbella, Málaga). Se revisaron las serologías para el VIH solicitadas en pacientes a los que se les pidió una PCR para Chlamydia trachomatis y Neisseria gonorrhoeae. Resultados: Se valoraron 1.818 pacientes, en los que se realizó serología para el VIH al 44,7%, de las cuales 14 (1,7%) resultaron positivas. El 55,3% restante fueron oportunidades perdidas de diagnóstico. Conclusiones: Las infecciones por C.trachomatis y N.gonorrhoeae están asociadas a una elevada tasa de infección oculta por el VIH. El grado de sospecha de VIH en esta población sigue siendo bajo, y resulta esencial que se refuerce ante la posibilidad de infección por estas patologías.(AU)

Introduction: Sexually transmitted diseases such as cervicitis, proctitis and urethritis are associated with high rates of HIV infection. When these pathologies are suspected, HIV serology should be requested. Material and methods: A Retrospective study was performed during 2018 at the Hospital Costa del Sol (Marbella, Málaga, Spain). HIV serologies requested in patients who were asked for PCR for Chlamydia trachomatis and Neisseria gonorrhoeae were reviewed. Results: A total of 1818 patients were evaluated, in which HIV serology was performed in 44.7%, of which 14 (1.7%) were positive. The remaining 55.3% were missed diagnostic opportunities. Conclusions: C.trachomatis and N.gonorrhoeae infections are associated with a high rate of occult HIV infection. The degree of suspicion of HIV in this population remains low and it is essential that it be reinforced in the presence of the possibility of infection by these pathologies.(AU)

Detection of a novel genotype of Chlamydia buteonis in falcons from the Emirates.

Chlamydiaceae are a family of obligate intracellular bacterial pathogens that affect both humans and animals. Recently, a new species named Chlamydia (C.) buteonis was isolated from hawks. In this study, we aimed to investigate the prevalence of Chlamydiaceae in 60 falcons that underwent a routine health check at a specialized clinic in Dubai, United Arab Emirates. Using real-time PCR, we analyzed cloacal and tracheal swabs from these birds and found that 39 of them tested positive for Chlamydiaceae. Subsequent real-time PCR assays specific for C. psittaci, C. abortus, C. avium, and C. gallinacea yielded negative results, while testing positive for C. buteonis. Analysis of ompA and MLST sequences indicated a highly conserved group of strains within this set of samples, but with sequences distinct from the C. buteonis RSHA reference strains and other C. buteonis strains isolated from hawks in the United States. Two strains were further isolated by cell culture and sequenced using whole-genome sequencing, confirming the clustering of these falcon strains within the C. buteonis species, but in a separate clade from the previously identified hawk strains. We also developed a SNP-based PCR-HRM assay to distinguish between these different genotypes. Overall, our findings suggest a high prevalence of C. buteonis in falcons in Dubai and highlight the importance of monitoring this pathogen in birds of prey.

Investigation of Chlamydia pecorum in livestock from Switzerland reveals a high degree of diversity in bovine strains.

Chlamydia pecorum is a widespread veterinary chlamydial species causing endemic infections in livestock, such as ruminants and pigs, globally. However, there is limited contemporary knowledge on infecting strain diversity in various hosts. This study aimed to evaluate the genetic diversity of C. pecorum strains infecting Swiss livestock through C. pecorum genotyping and phylogenetic analyses in comparison to the global population, while also assessing chlamydial strains for plasmid carriage. A total of 263 C. pecorum positive samples from clinically healthy ruminant and pig herds (Bovines = 216, sheep = 25, pigs = 14) as well as placentae from eight C. pecorum positive ruminant abortion cases from other Swiss herds were investigated. The ompA and Multi-Locus sequence typing revealed novel C. pecorum genotypes, and bovine strains exhibited considerable genetic diversity, contrasting with lower diversity in sheep and pig strains. C. pecorum plasmid was detected in 100.0% of sheep (41/41) and pig (255/255) samples, and in 69.4% of bovine samples (150/216). In contrast, no plasmid was detected in the eight C. pecorum-positive ruminant abortion cases either representing plasmid-less strains or possibly escaping PCR detection due to autolysis of the placenta. This study supports the genetic diversity of C. pecorum strains, particularly in bovines, and identifies novel sequence types in Swiss livestock.

Australian consensus statement on doxycycline post-exposure prophylaxis (doxy-PEP) for the prevention of syphilis, chlamydia and gonorrhoea among gay, bisexual and other men who have sex with men.

INTRODUCTION: Doxycycline post-exposure prophylaxis (doxy-PEP) involves consuming 200 mg of doxycycline up to 72 hours after a condomless sex act to reduce the risk of bacterial sexually transmitted infections (STIs). Recent clinical trials of doxy-PEP have demonstrated significant reductions in syphilis, chlamydia and, to a lesser degree, gonorrhoea among gay, bisexual and other men who have sex with men (GBMSM). There is a high level of interest in doxy-PEP in the GBMSM community and, in response, the Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine (ASHM) held a national consensus conference with the aim of creating preliminary guidance for clinicians, community, researchers and policy makers. MAIN RECOMMENDATIONS: There was broad agreement that doxy-PEP should be considered primarily for the prevention of syphilis in GBMSM who are at risk of this STI, with a secondary benefit of reductions in other bacterial STIs. At the end of the consensus process, there remained some disagreement, as some stakeholders felt strongly that doxy-PEP should be considered only for the prevention of syphilis in GBMSM, and that the risk of increasing antimicrobial resistance outweighed any potential benefit from reductions in other bacterial STIs in the target population. The national roundtable made several other recommendations for clinicians, community, researchers and policy makers, as detailed in this article. ASHM will support the development of detailed clinical guidelines and education materials on doxy-PEP (www.ashm.org.au/doxy-pep). CHANGES IN MANAGEMENT AS A RESULT OF THIS CONSENSUS STATEMENT: For GBMSM at high risk of syphilis, and perhaps other bacterial STIs, clinicians may consider prescribing doxy-PEP for a limited period of time, followed by a review of ongoing need. Unlike human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP), doxy-PEP may not be suitable as a population-level intervention and should instead be used more selectively.

Diversity and genetic characterization of Chlamydia isolated from Siamese crocodiles (Crocodylus siamensis).

Chlamydiosis, an infection caused by several Chlamydia species, has been reported in Nile, saltwater, and Siamese crocodiles. Despite its widespread reports in various countries, including Thailand, genetic information on Chlamydia species remains limited. This study presents a whole-genome-based characterization of Siamese crocodile-isolated Chlamydia. The results showed that Siamese crocodile Chlamydia contained a single circular chromosome with a size of 1.22-1.23 Mbp and a plasmid with a size of 7.7-8.0 kbp. A plasmid containing eight coding sequences (CDSs) was grouped in a ß lineage. A chromosome sequence had approximately 1,018-1,031 CDSs. Chlamydial factors involving virulence were documented in terms of the presence of cytotoxins and several virulence factors in the chromosomes of Siamese crocodile Chlamydia. The analysis of antimicrobial resistance genes in the Chlamydia genome revealed that the most common resistance genes were associated with aminoglycosides, fluoroquinolones, macrolides, tetracyclines, and cephalosporins, with loose matching (identities between 21.12 % and 74.65 %). Phylogenetic analyses, encompassing the assessments of both whole proteome and nine taxonomic markers, revealed that Siamese crocodile Chlamydia was separated into three lineages (lineages I-III) with high bootstrapping statistic support. Interestingly, isolate 12-01 differed genetically from the others, suggesting that it is a new member of Chlamydia. The study findings indicate that Siamese crocodiles are susceptible hosts to Chlamydia, involving more than one species. This study is the first employing the highest number of whole-genome data on Siamese crocodile Chlamydia and provides better insights into pathogen genetics.

Implementation of Point of Care Sexually Transmitted Infections Testing in a Community Clinic Setting.

ABSTRACT: The rates of sexually transmitted infections (STIs) in the United States, including chlamydia and gonorrhea, are rising. Point-of-care (POC) testing could increase access to testing and treatment. This evaluation found POC STI testing to be concordant with the results of traditional laboratory testing for 100% of patients who were tested. Ninety-five percent of the patients reported being satisfied with the experience, and 66% preferred it to traditional laboratory testing. The most commonly reported reason for preferring the test was the short amount of time it took to receive results. However, insurance reimbursed less than 30% of what was billed for the POC tests. Low insurance reimbursement rates could be a barrier to implementation long-term financial sustainability of POC STI testing.

Syphilis Diagnosis After a Chlamydia, Gonorrhea, or HIV Diagnosis Among Reproductive-Aged Women in Baltimore, MD.

BACKGROUND: Syphilis incidence is increasing among reproductive-aged women, and previous sexually transmitted infections (STIs) are a risk factor for subsequent STIs. This study aimed to determine syphilis incidence after a chlamydia, gonorrhea, or HIV diagnosis, and identify characteristics associated with higher syphilis incidence rates among reproductive-aged women in 1 mid-Atlantic city. METHODS: A retrospective cohort of 85,113 chlamydia, gonorrhea, and HIV diagnoses occurring between 2009 and 2021 and among women aged 13 to 50 years was constructed using public health surveillance data. Cumulative incidence curves were estimated to examine time to early syphilis (i.e., primary, secondary, or early latent) diagnosis, and multivariable analyses determined incidence rate ratios by age (<25 vs. ≥25 years) and number of prior STI diagnoses (0 vs. ≥1) during the study period, stratified by STI. RESULTS: There were 85,113 reportable STI diagnoses and 646 syphilis diagnoses in the cohort. Approximately 1 of 150 chlamydia, 1 of 100 gonorrhea, and 1 of 50 HIV diagnoses were followed by a syphilis diagnosis within 5 years. Cumulative incidence of syphilis differed significantly by STI diagnosis ( P < 0.001). In multivariable analysis, syphilis incidence rates were higher among women diagnosed with ≥1 (vs. 0) prior STI regardless of STI type ( P < 0.05) and among women ≥25 (vs. <25) years old diagnosed with gonorrhea ( P < 0.05). CONCLUSIONS: There were significant differences in syphilis incidence by prior STI type, number of STIs, and age. Our data support targeted screening for syphilis among women with a history of STIs, parwomen with ≥1 prior STI diagnosis, and older women diagnosed with gonorrhea.

Immune signature of Chlamydia vaccine CTH522/CAF®01 translates from mouse-to-human and induces durable protection in mice.

The clinical development of an effective Chlamydia vaccine requires in-depth understanding of how well protective pre-clinical immune signatures translate to humans. Here, we report a comparative immunological characterization of CTH522/CAF®01 in female mice and humans. We find a range of immune signatures that translate from mouse to human, including a Th1/Th17 cytokine profile and antibody functionality. We identify vaccine-induced T cell epitopes, conserved among Chlamydia serovars, and previously found in infected individuals. Using the mouse model, we show that the common immune signature protected against ascending infection in mice, and vaccine induced antibodies could delay bacterial ascension to the oviduct, as well as development of pathology, in a T cell depleted mouse model. Finally, we demonstrate long-lasting immunity and protection of mice one year after vaccination. Based on the results obtained in the present study, we propose to further investigate CTH522/CAF®01 in a phase IIb study.

Seroprevalence and Risk Factors of Chlamydia Infection in Pigs in Hunan Province, Southern China, 2017-2018.

Background: Chlamydia is a Gram-negative obligate intracellular bacterium that is pathogenic for humans and a large variety of veterinary animal species. However, there is no continuous monitoring of chlamydia infection data in pigs in Hunan province, southern China. Therefore, in order to evaluate the seroprevalence and identify risk factors associated with Chlamydia infection in pigs within this region, a comprehensive study was conducted. Methods: A total of 3848 serum samples were collected from pigs (from farmers and companies) between May 2017 and August 2018. The presence of specific antibodies against Chlamydia was determined through the employment of the indirect hemagglutination assay (IHA). Results: The overall seroprevalence of Chlamydia was determined to be 26.90% (1038/3848, 95% confidence interval: 25.60-28.40). By employing statistical analysis using SPSS software (p < 0.05), factors such as altitude, sampling regions, and rearing systems of pigs were identified as potential risk factors for Chlamydia infection. Conclusion: These findings elucidate a substantial prevalence of Chlamydia in pigs within the mountainous region of Hunan province, southern China, thereby highlighting a potential risk to human health. These results underscore the need for proactive measures and targeted interventions to mitigate the transmission of Chlamydia in porcine populations, safeguarding both animal welfare and public health.

Chlamydia retesting remains low among young women in Australia: an observational study using sentinel surveillance data, 2018-2022.

BACKGROUND: Chlamydia remains the most notified bacterial sexually transmissible infection in Australia with guidelines recommending testing for re-infection at 3months post treatment. This paper aimed to determine chlamydia retesting and repeat positivity rates within 2-4months among young women in Australia, and to evaluate what factors increase or decrease the likelihood of retesting. METHODS: Chlamydia retesting rates among 16-29-year-old women were analysed from Australian Collaboration for Coordinated Enhanced Sentinel Surveillance of sexually transmissible infection and bloodborne virus (ACCESS) sentinel surveillance data (n =62 sites). Among women with at least one positive test between 1 January 2018 and 31 August 2022, retesting counts and proportions within 2-4months were calculated. Logistic regression was performed to assess factors associated with retesting within 2-4months. RESULTS: Among 8758 women who were positive before 31 August 2022 to allow time for follow up, 1423 (16.2%) were retested within 2-4months, of whom 179 (12.6%) tested positive. The odds of retesting within 2-4months were 25% lower if tested in a coronavirus disease 2019 (COVID-9) pandemic year (2020-2022) (aOR=0.75; 95% CI 0.59-0.95). Among 9140 women with a positive test before 30 November 2022, 397 (4.3%) were retested too early (within 7days to 1month) and 81 (20.4%) of those were positive. CONCLUSIONS: Chlamydia retesting rates remain low with around a sixth of women retested within 2-4months in line with guidelines. Re-infection is common with around one in eight retesting positive. An increase in retesting is required to reduce the risk of reproductive complications and onward transmission.

Expanding the known distribution of phascolartid gammaherpesvirus 1 in koalas to populations across Queensland and New South Wales.

Koala populations across the east coast of Australia are under threat of extinction with little known about the presence or distribution of a potential pathogen, phascolartid gammaherpesvirus 1 (PhaHV-1) across these threatened populations. Co-infections with PhaHV-1 and Chlamydia pecorum may be common and there is currently a limited understanding of the impact of these co-infections on koala health. To address these knowledge gaps, archived clinical and field-collected koala samples were examined by quantitative polymerase chain reaction to determine the distribution of PhaHV-1 in previously untested populations across New South Wales and Queensland. We detected PhaHV-1 in all regions surveyed with differences in detection rate between clinical samples from rescued koalas (26%) and field-collected samples from free-living koalas (8%). This may reflect increased viral shedding in koalas that have been admitted into care. We have corroborated previous work indicating greater detection of PhaHV-1 with increasing age in koalas and an association between PhaHV-1 and C. pecorum detection. Our work highlights the need for continued surveillance of PhaHV-1 in koala populations to inform management interventions, and targeted research to understand the pathogenesis of PhaHV-1 and determine the impact of infection and co-infection with C. pecorum.