SARS-CoV-2 breakthrough infection induces rapid memory and de novo T cell responses.

Although the protective role of neutralizing antibodies against COVID-19 is well established, questions remain about the relative importance of cellular immunity. Using 6 pMHC multimers in a cohort with early and frequent sampling, we define the phenotype and kinetics of recalled and primary T cell responses following Delta or Omicron breakthrough infection in previously vaccinated individuals. Recall of spike-specific CD4+ T cells was rapid, with cellular proliferation and extensive activation evident as early as 1 day post symptom onset. Similarly, spike-specific CD8+ T cells were rapidly activated but showed variable degrees of expansion. The frequency of activated SARS-CoV-2-specific CD8+ T cells at baseline and peak inversely correlated with peak SARS-CoV-2 RNA levels in nasal swabs and accelerated viral clearance. Our study demonstrates that a rapid and extensive recall of memory T cell populations occurs early after breakthrough infection and suggests that CD8+ T cells contribute to the control of viral replication in breakthrough SARS-CoV-2 infections.

The magnitude and timing of recalled immunity after breakthrough infection is shaped by SARS-CoV-2 variants.

Vaccination against SARS-CoV-2 protects from infection and improves clinical outcomes in breakthrough infections, likely reflecting residual vaccine-elicited immunity and recall of immunological memory. Here, we define the early kinetics of spike-specific humoral and cellular immunity after vaccination of seropositive individuals and after Delta or Omicron breakthrough infection in vaccinated individuals. Early longitudinal sampling revealed the timing and magnitude of recall, with the phenotypic activation of B cells preceding an increase in neutralizing antibody titers. While vaccination of seropositive individuals resulted in robust recall of humoral and T cell immunity, recall of vaccine-elicited responses was delayed and variable in magnitude during breakthrough infections and depended on the infecting variant of concern. While the delayed kinetics of immune recall provides a potential mechanism for the lack of early control of viral replication, the recall of antibodies coincided with viral clearance and likely underpins the protective effects of vaccination against severe COVID-19.

SARS-CoV-2-specific T cell memory with common TCRαß motifs is established in unvaccinated children who seroconvert after infection.

As the establishment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cell memory in children remains largely unexplored, we recruited convalescent COVID-19 children and adults to define their circulating memory SARS-CoV-2-specific CD4+ and CD8+ T cells prior to vaccination. We analyzed epitope-specific T cells directly ex vivo using seven HLA class I and class II tetramers presenting SARS-CoV-2 epitopes, together with Spike-specific B cells. Unvaccinated children who seroconverted had comparable Spike-specific but lower ORF1a- and N-specific memory T cell responses compared with adults. This agreed with our TCR sequencing data showing reduced clonal expansion in children. A strong stem cell memory phenotype and common T cell receptor motifs were detected within tetramer-specific T cells in seroconverted children. Conversely, children who did not seroconvert had tetramer-specific T cells of predominantly naive phenotypes and diverse TCRαß repertoires. Our study demonstrates the generation of SARS-CoV-2-specific T cell memory with common TCRαß motifs in unvaccinated seroconverted children after their first virus encounter.

Neisseria gonorrhoeae vaccines: a contemporary overview.

Neisseria gonorrhoeae infection is an important public health issue, with an annual global incidence of 87 million. N. gonorrhoeae infection causes significant morbidity and can have serious long-term impacts on reproductive and neonatal health and may rarely cause life-threatening disease. Global rates of N. gonorrhoeae infection have increased over the past 20 years. Importantly, rates of antimicrobial resistance to key antimicrobials also continue to increase, with the United States Centers for Disease Control and Prevention identifying drug-resistant N. gonorrhoeae as an urgent threat to public health. This review summarizes the current evidence for N. gonorrhoeae vaccines, including historical clinical trials, key N. gonorrhoeae vaccine preclinical studies, and studies of the impact of Neisseria meningitidis vaccines on N. gonorrhoeae infection. A comprehensive survey of potential vaccine antigens, including those identified through traditional vaccine immunogenicity approaches, as well as those identified using more contemporary reverse vaccinology approaches, are also described. Finally, the potential epidemiological impacts of a N. gonorrhoeae vaccine and research priorities for further vaccine development are described.

Prevalence of cefixime-resistant Neisseria gonorrhoeae in Melbourne, Australia, 2021-2022.

While ceftriaxone remains the first-line treatment for gonorrhoea, the US CDC recommended cefixime as a second-line treatment in 2021. We tested 1176 Neisseria gonorrhoeae isolates among clients attending the Melbourne Sexual Health Centre in 2021-2022. The prevalence of cefixime resistance was 6.3% (74/1176), azithromycin resistance was 4.9% (58/1176) and ceftriaxone resistance was 0% (0/1176). Cefixime resistance was the highest among women (16.4%, 10/61), followed by men-who-have-sex-with-women (6.4%, 7/109), and men-who-have-sex-with-men (5.8%, 57/982). The prevalence of cefixime-resistant N. gonorrhoeae exceeds the threshold of the 5% resistance level recommended by the World Health Organization; and thus, cefixime treatment would have limited benefits in Australia.

Evaluating preanalytical sample storage parameters for nucleic acid-based detection of Neisseria gonorrhoeae.

OBJECTIVES: To ensure accurate diagnosis of infectious diseases, preanalytical factors should be considered when assessing specimen quality and subsequent test result. Accordingly, we aimed to systematically assess the effect of storage time, temperature and buffer on the analytical sensitivity of detecting the sexually transmitted pathogen, Neisseria gonorrhoeae across multiple molecular diagnostic platforms. METHODS: Cultured N. gonorrhoeae was spiked into generic and commercial storage buffers and stored at four temperatures and five time points, ranging from -20°C to 37°C, over 30 days. Samples were processed using the Alinity m STI, Xpert CT/NG and Aptima Combo 2 nucleic acid amplification assays and an in-house quantitative PCR assay. A reduction in analytical sensitivity was defined as a significant (p<0.05) increase in cycle threshold (Ct) value relative to control samples. RESULTS: In total, 2756 samples were processed, with N. gonorrhoeae detected in 99.2% of samples. With respect to time, analytical sensitivity was maintained from day 2 (113/120; 94.2%) up to day 30 (110/120; 91.7%) relative to baseline samples. With respect to temperature, analytical sensitivity was maintained from -20°C (147/150; 98.0%) up to 37°C (136/150; 90.7%) relative to baseline samples. Generic buffers, Viral Transport Medium and Amies Liquid Media showed a reduction in analytical sensitivity compared with their commercial counterparts, Aptima Multitest Swab Transport Media and Abbott Alinity transport buffer using select diagnostic assays; this reduction appeared temperature dependent, with the largest differences in median Ct values observed at 37°C (p<0.05). CONCLUSIONS: Increased prevalence of sample self-collection for sexually transmitted infections (STIs) warrants an evaluation of preanalytical sample storage variables on diagnostic testing performance. Here, across a range of time points, temperatures and storage buffers, N. gonorrhoeae was successfully detected, supporting flexibility in sample storage, and by extension the feasibility of analysing self-collected samples to improve access to STI testing.

Serosurvey for Japanese encephalitis virus antibodies following an outbreak in an immunologically naïve population, Victoria, 2022: a cross-sectional study.

OBJECTIVES: To investigate the distribution and prevalence of Japanese encephalitis virus (JEV) antibody (as evidence of past infection) in northern Victoria following the 2022 Japanese encephalitis outbreak, seeking to identify groups of people at particular risk of infection; to investigate the distribution and prevalence of antibodies to two related flaviviruses, Murray Valley encephalitis virus (MVEV) and West Nile virus Kunjin subtype (KUNV). STUDY DESIGN: Cross-sectional serosurvey (part of a national JEV serosurveillance program). SETTING: Three northern Victorian local public health units (Ovens Murray, Goulburn Valley, Loddon Mallee), 8 August - 1 December 2022. PARTICIPANTS: People opportunistically recruited at pathology collection centres and by targeted recruitment through community outreach and advertisements. People vaccinated against or who had been diagnosed with Japanese encephalitis were ineligible for participation, as were those born in countries where JEV is endemic. MAIN OUTCOME MEASURES: Seroprevalence of JEV IgG antibody, overall and by selected factors of interest (occupations, water body exposure, recreational activities and locations, exposure to animals, protective measures). RESULTS: 813 participants were recruited (median age, 59 years [interquartile range, 42-69 years]; 496 female [61%]); 27 were JEV IgG-seropositive (3.3%; 95% confidence interval [CI], 2.2-4.8%) (median age, 73 years [interquartile range, 63-78 years]; 13 female [48%]); none were IgM-seropositive. JEV IgG-seropositive participants were identified at all recruitment locations, including those without identified cases of Japanese encephalitis. The only risk factors associated with JEV IgG-seropositivity were age (per year: prevalence odds ratio [POR], 1.07; 95% CI, 1.03-1.10) and exposure to feral pigs (POR, 21; 95% CI, 1.7-190). The seroprevalence of antibody to MVEV was 3.0% (95% CI, 1.9-4.5%; 23 of 760 participants), and of KUNV antibody 3.3% (95% CI, 2.1-4.8%; 25 of 761). CONCLUSIONS: People living in northern Victoria are vulnerable to future JEV infection, but few risk factors are consistently associated with infection. Additional prevention strategies, including expanding vaccine eligibility, may be required to protect people in this region from Japanese encephalitis.

A case of swine influenza A(H1N2)v in England, November 2023.

Under International Health Regulations from 2005, a human infection caused by a novel influenza A virus variant is considered an event that has potential for high public health impact and is immediately notifiable to the World Health Organisation. We here describe the clinical, epidemiological and virological features of a confirmed human case of swine influenza A(H1N2)v in England detected through community respiratory virus surveillance. Swabbing and contact tracing helped refine public health risk assessment, following this unusual and unexpected finding.

Changes in the Syphilis Rapid Plasma Reagin Titer Between Diagnosis and Treatment.

BACKGROUND: We compared the rapid plasma reagin (RPR) titer on the day of initial presentation with that on the day of syphilis treatment to inform clinical practice as to whether a repeated RPR test should be recommended. METHODS: We undertook a retrospective study between 1 March 2011 and 31 December 2020 at the Melbourne Sexual Health Centre in Australia among individuals who underwent syphilis serology on the day of initial presentation and the day of treatment, if the latter were within 14 days after initial presentation. We calculated the percentage of individuals with a ≥4-fold change in RPR titer, stratified by the time between initial presentation and treatment and by syphilis stage. RESULTS: Among the 766 included syphilis cases, the median duration between initial presentation and treatment was 6 days (interquartile range, 5-7 days). Of these cases, 14.8% (n = 113) had a ≥4-fold increase or decrease during this interval. The number of cases with a ≥4-fold increase or decrease in RPR titer increased with increasing time between initial presentation and treatment, from 5.7% (n = 6) 1-3 days after initial presentation to 26.2% (n = 27) at 10-14 days (Ptrend < .001). There was no significant difference in the number of cases with a ≥4-fold increase or decrease in RPR titer between syphilis stages (P = .66). CONCLUSIONS: Our data support the recommendation of repeating the RPR titer if the day of initial presentation and the day of treatment are different, even when treatment is within a few days after initial presentation.

Treponema pallidum Detection at Asymptomatic Oral, Anal, and Vaginal Sites in Adults Reporting Sexual Contact with Persons with Syphilis.

We investigated Treponema pallidum PCR positivity at mucosal sites (oral, anal, and vaginal sites) among adults who had sexual contact with a person with syphilis (syphilis contacts). All syphilis contacts had oral rinse and swab samples collected for testing. Men who have sex with men had anal swab and women had vaginal swab samples collected for testing, regardless of the presence of lesions. Of 407 persons tested, 42 (10%) had early syphilis diagnosed; of those, 19 (45%) tested positive by PCR from any anatomic site and had a positive serologic test. T. pallidum was positive from vaginal samples in 3 women, anal samples in 3 men, and oral cavity samples in 2 women and 3 men, without symptoms at those sites. Three women had no prior syphilis serologic test. T. pallidum detection at asymptomatic mucosal sites suggests early syphilis infections, particularly in cases that would conventionally be staged as latent syphilis of unknown duration.

Clinical relevance of topical antibiotic use in co-selecting for multidrug-resistant Staphylococcus aureus: Insights from in vitro and ex vivo models.

Topical antibiotic preparations, such as fusidic acid (FA) or mupirocin, are used in the prevention and treatment of superficial skin infections caused by staphylococci. Previous genomic epidemiology work has suggested an association between the widespread use of topical antibiotics and the emergence of methicillin resistant Staphylococcus aureus in some settings. In this study, we provide experimental proof of co-selection for multidrug resistance in S. aureus following exposure to FA or mupirocin. Through targeted mutagenesis and phenotypic analyses, we confirmed that fusC carriage confers resistance to FA, and mupA carriage confers high-level resistance to mupirocin in multiple S. aureus genetic backgrounds. In vitro experiments demonstrated that carriage of fusC and mupA confer a competitive advantage in the presence of sub-inhibitory concentrations of FA and mupirocin, respectively. Further, we used a porcine skin colonisation model to show that clinically relevant concentrations of topical antibiotics can co-select for presence of unrelated antimicrobial resistance determinants, such as mecA, blaZ, and qacA, in fusC or mupA harbouring S. aureus These findings provide valuable insights on the role of acquired FA or mupirocin resistance in co-selecting for broader antibiotic resistance in S. aureus, prompting greater need for judicious use of topical antibiotics.

Intra- and interhost genomic diversity of monkeypox virus.

The impact and frequency of infectious disease outbreaks demonstrate the need for timely genomic surveillance to inform public health responses. In the largest known outbreak of mpox, genomic surveillance efforts have primarily focused on high-incidence nations in Europe and the Americas, with a paucity of data from South-East Asia and the Western Pacific. Here we analyzed 102 monkeypox virus (MPXV) genomes sampled from 56 individuals in Melbourne, Australia. All genomes fell within the 2022 MPXV outbreak lineage (B.1), with likely onward local transmission detected. We observed within-host diversity and instances of co-infection, and highlight further examples of structural variation and apolipoprotein B editing complex-driven micro-evolution in the current MPXV outbreak. Updating our understanding of MPXV emergence and diversification will inform public health measures and enable monitoring of the virus' evolutionary trajectory throughout the mpox outbreak.

Sentinel cluster of locally acquired Japanese encephalitis in southern Australia.

Prior to January 2022, only a single case of infection with Japanese encephalitis virus (JEV) had been reported on the Australian mainland, acquired in the northern extremity on Cape York. We report the clinical characteristics of the sentinel cluster of cases that confirmed the local acquisition of JEV in southern Australia along the Murray River bordering New South Wales and Victoria.

Mpox knowledge, vaccination and intention to reduce sexual risk practices among men who have sex with men and transgender people in response to the 2022 mpox outbreak: a cross-sectional study in Victoria, Australia.

BACKGROUND: The first mpox case was reported in May 2022 in Australia. Most cases have been diagnosed in men who have sex with men (MSM). This study aimed to examine community understanding of mpox, attitudes towards vaccination, and potential changes in sexual practices surrounding the mpox outbreak among MSM and transgender people in Victoria, Australia. METHODS: Participants were recruited from sexual health clinics and communities in Victoria, Australia, in August-October 2022. Participants were asked about their understanding and knowledge of mpox, vaccination uptake and intentions to change sexual practices. Univariable and multivariable logistic regression was performed to examine the factors associated with mpox vaccine uptake. RESULTS: Most participants (97.8%, 525/537) had heard about mpox and 10.5% (55/525) knew someone who had had mpox. Of the 12 mpox knowledge questions, the median score of correct answers was 10 (IQR=8-11) out of a maximum of 12. More than a third (36.6%, 191/522) had been vaccinated against mpox. MSM who had a good knowledge of mpox had the highest odds of receiving mpox vaccine compared with those who had poor knowledge (aOR=4.05; 95% CI: 1.54-10.61). To prevent mpox, half reported they would reduce having sex with casual partners, stop having chemsex (used drugs for the purpose of sex), stop attending sex-on-premises-venues, and stop having group sex. A quarter reported they would increase condom use for anal sex. CONCLUSIONS: One-third of high-risk participants and a substantial proportion of participants intended to reduce or stop certain practices, which may explain the large reduction in mpox cases.

Increased Breadth of Group A Streptococcus Antibody Responses in Children With Acute Rheumatic Fever Compared to Precursor Pharyngitis and Skin Infections.

BACKGROUND: Group A Streptococcus (GAS) causes superficial pharyngitis and skin infections as well as serious autoimmune sequelae such as acute rheumatic fever (ARF) and subsequent rheumatic heart disease. ARF pathogenesis remains poorly understood. Immune priming by repeated GAS infections is thought to trigger ARF, and there is growing evidence for the role of skin infections in this process. METHODS: We utilized our recently developed 8-plex immunoassay, comprising antigens used in clinical serology for diagnosis of ARF (SLO, DNase B, SpnA), and 5 conserved putative GAS vaccine antigens (Spy0843, SCPA, SpyCEP, SpyAD, Group A carbohydrate), to characterize antibody responses in sera from New Zealand children with a range of clinically diagnosed GAS disease: ARF (n = 79), GAS-positive pharyngitis (n = 94), GAS-positive skin infection (n = 51), and matched healthy controls (n = 90). RESULTS: The magnitude and breadth of antibodies in ARF was very high, giving rise to a distinct serological profile. An average of 6.5 antigen-specific reactivities per individual was observed in ARF, compared to 4.2 in skin infections and 3.3 in pharyngitis. CONCLUSIONS: ARF patients have a unique serological profile, which may be the result of repeated precursor pharyngitis and skin infections that progressively boost antibody breadth and magnitude.

Combination Therapy for Mycoplasma genitalium, and New Insights Into the Utility of parC Mutant Detection to Improve Cure.

BACKGROUND: Mycoplasma genitalium (MG) infection is challenging to cure because of rising antimicrobial resistance and limited treatment options. METHODS: This was a prospective evaluation of the efficacy and tolerability of resistance-guided combination antimicrobial therapy for MG treatment at Melbourne Sexual Health Centre (August 2019-December 2020). All patients received 7 days of doxycycline before combination therapy based on the macrolide-resistant profile. Macrolide-susceptible infections received combination doxycycline + azithromycin (1 g, day 1; 500 mg, days 2-4) and macrolide-resistant infections combination doxycycline + moxifloxacin (400 mg daily for 7 days). Adherence and adverse effects were recorded at test-of-cure, recommended 14-28 days after antimicrobial completion. Sequencing was performed to determine the prevalence of single nucleotide polymorphisms (SNPs) in the parC gene and their association with moxifloxacin treatment outcomes in macrolide-resistant infections. RESULTS: Of 100 patients with macrolide-susceptible MG treated with doxycycline + azithromycin, 93 were cured (93.0%; 95% confidence interval [CI], 86.1-97.1). Of 247 patients with macrolide-resistant MG receiving doxycycline + moxifloxacin, 210 were cured (85.0%; 95% CI, 80.0-89.2). parC sequencing was available for 164 (66%) macrolide-resistant infections; 29% had SNPs at parC S83 or D87 (23% S83I). The absence of SNPs at parC S83/D87 was associated with 98.3% cure (95% CI, 93.9-99.8) following doxycycline + moxifloxacin. The presence of the parC S83I-SNP was associated with failure in 62.5% (95% CI, 45.8-77.3). Side effects were common (40%-46%) and predominantly mild and gastrointestinal. CONCLUSIONS: Combination doxycycline + azithromycin achieved high cure for macrolide-susceptible infections. However, in the context of a high prevalence of the parC S83I mutation (23%) in macrolide-resistant infections, doxycycline + moxifloxacin cured only 85%. Infections that were wild-type for S83/D87 experienced high cure following doxycycline + moxifloxacin, supporting the use of a parC-resistance/susceptibility testing strategy in clinical care.

Culture obtained from urethral swab of asymptomatic men who screen positive for Neisseria gonorrhoeae by urine nucleic acid amplification testing.

BACKGROUND: In a previous study of men attending Melbourne Sexual Health Centre who had Neisseria gonorrhoeae detected by urine Aptima Combo 2 (AC2) testing, 11% were asymptomatic. This study aimed to determine whether N. gonorrhoeae can be cultured from asymptomatic men screening positive for N. gonorrhoeae by nucleic acid amplification testing (NAAT) of urine. METHODS: Between 1 July 2017 and 31 March 2019, all men attending Melbourne Sexual Health Centre were tested for N. gonorrhoeae by AC2 testing of urine whether urethral symptoms were reported or not. NAAT-positive men were recalled and a urethral swab performed for gonococcal culture using modified Thayer-Martin media with determination of minimum inhibitory concentrations (MICs) by agar dilution. RESULTS: There were 1001 cases (860 individuals) positive for N. gonorrhoeae by urine AC2: 892 (89%) reported urethral symptoms; 109 (11%) did not. Twenty-five asymptomatic cases were excluded because of antibiotic use at or following screening. Of the remaining 84 asymptomatic men, 41 (49%) had a urethral swab performed a median of 5 days after screening. Twenty-one men had urethral discharge at the return visit, 11 of whom reported the discharge at the return visit. Of the 41 men who were swabbed, 31 (76%; 95% CI 60% to 88%) were culture positive for N. gonorrhoeae. Among the 21 men who subsequently developed discharge, 19 (90%; 95% CI 70% to 99%) were culture positive. Among the 20 men who remained asymptomatic, 12 (60%; 95% CI 36% to 81%) were culture positive. MIC profiles were obtained from all isolates. CONCLUSIONS: Gonorrhoea was isolated in most but not all asymptomatic men screening positive for N. gonorrhoeae by urine NAAT. Clinicians should consider performing urethral culture in such men to ensure optimal surveillance for antimicrobial resistance. Isolation of N. gonorrhoeae by culture in men without discharge indicates these are true infections with viable organisms.

Timing of primary syphilis treatment and impact on the development of treponemal antibodies: a cross-sectional clinic-based study.

BACKGROUND: Serology is negative in a proportion of primary syphilis cases where Treponema pallidum PCR testing is positive. We aimed to identify discordant, T. pallidum PCR-positive, serology-negative primary syphilis cases and any clinical or laboratory factors associated with failure to subsequently seroconvert. METHODS: Serodiscordant primary syphilis cases that were T. pallidum PCR-positive and serology-negative (including rapid plasma reagin, T. pallidum particle agglutination, T. pallidum enzyme immunoassay or T. pallidum chemiluminescence assay) were identified from the Melbourne Sexual Health Centre electronic records between April 2011 and December 2019. Clinical and laboratory associations were examined. RESULTS: There were 814 primary syphilis cases in the study period and 38 (4.7%) were serodiscordant, 35 in men who have sex with men. Thirty-two had follow-up serology performed a median of 24 days later, of which 16 (50%) seroconverted, mostly (81%) within 6 weeks. Failure to seroconvert was significantly associated with treatment on day 1. Of the 12 cases treated on day 1, 10 (83%) failed to seroconvert compared with 6 of 20 (30%) among those who were treated after day 1. DISCUSSION: Earlier treatment of primary syphilis can prevent the development of serological markers. T. pallidum PCR can identify primary syphilis lesions before the development of serological markers and improve diagnosis of early primary syphilis lesions. Serology alone will miss a proportion of primary syphilis infections and should be repeated if a diagnosis of syphilis is being considered.

Comparison of the patterns of chlamydia and gonorrhoea at the oropharynx, anorectum and urethra among men who have sex with men.

OBJECTIVE: Chlamydia and gonorrhoea are common sexually transmitted infections that infect the oropharynx, anorectum and urethra in men who have sex with men (MSM). This study aimed to examine the pattern of infection at more than one site (multisite) for chlamydia and gonorrhoea among MSM. METHODS: This was a retrospective study of MSM attending the Melbourne Sexual Health Centre for the first time between 2018 and 2019. We included MSM aged ≥16 years who had tested for Neisseria gonorrhoeae and Chlamydia trachomatis at all three sites (oropharynx, anorectum and urethra). We compared infections that occurred at a single site (termed single-site infection) and those that occurred at more than one site (termed multisite infections). RESULTS: Of the 3938 men who were tested for chlamydia and gonorrhoea, 498/3938 men (12.6%, 95% CI 11.5% to 13.6%) had chlamydia at any site, of whom 400/498 (80.3%, 95% CI 78.9% to 81.2%) had single-site chlamydia infection, and 98/498 (19.7%, 95% CI 16.2% to 23.1%) had multisite infections. A similar proportion of men had gonorrhoea at any site (447/3938, 11.4%, 95% CI 10.3% to 12.2%), but among these 447 men, single-site infection was less common (256/447, 57.3%, 95% CI 52.6% to 61.7%, p<0.001) and multisite infection (191/447, 42.7%, 95% CI 38.2% to 47.3%, p<0.001) was more common than chlamydia. There were also marked differences by anatomical site. Urethral infection commonly occurred as single sites (75/122, 61.5%, 95% CI 52.8% to 70.1%) for chlamydia but uncommonly occurred for gonorrhoea (12/100, 12.0%, 95% CI 5.6% to 18.3%, p<0.001). In contrast, anorectal infection uncommonly occurred as multisite infection for chlamydia (98/394, 24.9%, 95% CI 20.6% to 29.1%) but was common (184/309, 59.5%, 95% CI 54.0% to 64.9%, p<0.001) for gonorrhoea. CONCLUSIONS: The markedly different pattern of site-specific infection for chlamydia and gonorrhoea infections among the same MSM suggests significant differences in the transmissibility between anatomical sites and the duration of each infection at each site.

Monkeypox infection presenting as genital rash, Australia, May 2022.

Rapid diagnosis and whole genome sequencing confirmed a case of monkeypox in an HIV-positive individual receiving antiretroviral therapy. The patient had a normal CD4+ T-cell count and suppressed HIV viral load and presented with a genital rash in Melbourne, Australia after return from Europe in May 2022. He subsequently developed systemic illness and disseminated rash and 11 days after symptom onset, he was hospitalised to manage painful bacterial cellulitis of the genital area.