Marcus Chen is a sexual health physician and researcher and Professor at the School of Translational Medicine, Monash University. He is a specialist in sexual health medicine at the Melbourne Sexual Health Centre, Alfred Health, a Fellow of the Royal College of Physicians, and a Fellow of the Australasian Chapter of Sexual Health Medicine. 

Chen’s research has focused on improving the management of sexually transmitted infections (STIs). Since receiving his PhD in 2006, he has published 380 papers in peer reviewed journals. These publications have been referenced by researchers in 120 countries and influenced policy and practice on STIs internationally.

Chen is an NHMRC Leadership Fellow and lead investigator on an NHMRC Partnership Project Grant which is designing and trialing innovative methods to improve testing and management of syphilis in the context of growing syphilis epidemics in Australia and other countries.

Chen was a member of the Australian Government Ministerial Advisory Committee on Blood Borne Viruses and STIs and is an advisor to the US Centers for Diseases Control STI Treatment Guidelines. Chen was a member of the working group for the Australian National STI Strategy and was chair of the Australasian contact tracing guidelines. He has served on national and state committees responsible for developing guidelines and policy on gonorrhoea and syphilis management and control.

Chen led the development of the web based contact tracing service Let Them Know, which has been used by individuals diagnosed with STIs to contact over half a million partners. He established and oversees the Victorian Sexual Health Network of sexual health services in general practice after this was recommended by the Victorian Government Review of Sexual Health Services.

In 2011 Chen received the Award for Significant Contribution to Sexual Health Medicine, and in 2019, the Award for Outstanding Contribution to Research in Sexual Health Medicine from the Australasian Chapter for Sexual Health Medicine. He and fellow researchers won the Australian Eureka Prize for Infectious Diseases in 2022. 

Publication highlights:

Review article

Williamson D, Chen M. Emerging and re-emerging sexually transmitted infections. New England Journal of Medicine 2020; 382: 2023-32.

Editorials

Chen M, Williamson D. Sexually acquired enteric infections among men who have sex with men. Lancet Infectious Diseases 2023; 23(6): 644-5.

Chen M, Williamson D. Sexually transmitted outbreaks and genomic surveillance. Lancet Infectious Diseases 2022; 22(10): 1409-11.

Original research

Aung E...Chen M. Detection of Treponema pallidum at asymptomatic oral, anal and vaginal sites in men and women reporting sexual contact with syphilis. Emerging Infectious Diseases 2023; 29(10): 2083-2092. 

Towns J...Chen M. Persistence of mpox virus at oral and rectal sites following resolution of cutaneous lesions. Lancet Microbe 2023; 4(4): e210. 

Towns J...Chen M. Clinical and laboratory aspects of condylomata lata lesions of syphilis. Sexually Transmitted Infections 2023; 99(3): 162-6.

Chow E...Chen M. Human papillomavirus antibody levels following vaccination or natural infection among young men who have sex with men. Clinical Infectious Diseases 2022; 75(2): 323-9.

Towns J...Chen M. Anal and oral detection of Treponema pallidum in men who have sex with men with early syphilis infection. Sexually Transmitted Infections 2022; 98: 570-4.

Towns J...Chen M. Timing of primary syphilis treatment and impact on the development of treponemal antibodies: a cross-sectional clinic-based study. Sexually Transmitted Infections 2022; 98(3): 161-5.

Towns J…Chen M. Oral and anal Treponema pallidum detection in lesion and non-lesion sites in men who have sex with men with early infectious syphilis: a prospective cross-sectional study. Lancet Infectious Diseases 2021; 21(9): 1324-31.

Chow E...Chen M. Non-classical pathogens as causative agents of proctitis in men who have sex with men. Open Forum Infectious Diseases 2021; 8(7): ofab137.

Peel J…Chen M. Clinical presentation of incident syphilis among men who have sex with men taking HIV Pre-Exposure Prophylaxis in Melbourne, Australia. Clinical Infectious Diseases 2021; 73(4): e934-7.

Chow E…Chen M. Prevalence of human papillomavirus in young men who have sex with men after the implementation of gender-neutral HPV vaccination: a repeated cross-sectional study. Lancet Infectious Diseases 2021; 21(10): 1448-57.

Tao Y, Chen M...Zhang L. A nationwide spaciotemporal analysis of syphilis over 21 years and implications for prevention and control in China. Clinical Infectious Diseases 2020; 70(1): 136-9.

Chen M…Oldach D. Solithromycin versus ceftriaxone plus azithromycin for the treatment of uncomplicated genital gonorrhoea: a randomised phase 3 non-inferiority trial. Lancet Infectious Diseases 2019; 19: 833-42.

Williamson D…Chen M & Howden B. Bridging of Neisseria gonorrhoeae lineages across sexual networks in the HIV pre-exposure prophylaxis era. Nature Communications 2019; 10: 3988.

Williamson D...Chen M. Risk factors for asymptomatic enteric pathogen detection among men who have sex with men. Open Forum Infectious Diseases 2019; 6(9): 326.

Kwong J...Chen M & Howden B. Whole genome sequencing reveals transmission of gonococcal antibiotic resistance among men who have sex with men: an observational study. Sexually Transmitted Infections 2018; 94(2): 151-7.

Chow E…Chen M. Increased syphilis testing of men who have sex with men: greater detection of asymptomatic early syphilis and relative reduction in secondary syphilis. Clinical Infectious Diseases 2017; 65(3): 389-95.

Machalek DA…Chen M & Tabrizi S. Human papillomavirus prevalence in unvaccinated heterosexual males following a national female vaccination program. Journal of Infectious Diseases 2017; 215: 202-8.

Ong J...Chen M. Asymptomatic and symptomatic urethral gonorrhoea in men who have sex with men attending a sexual health service. Clinical Microbiology and Infection 2017; 23(8): 555-9.

Priest D...Chen M. Neisseria gonorrhoeae DNA bacterial load in men with symptomatic and asymptomatic gonococcal urethritis. Sexually Transmitted Infections 2017; 93(7): 478-81.

Cornelisse V...Chen M. Increased detection of pharyngeal and rectal gonorrhea in men who have sex with men after transition from culture to nucleic acid amplification testing. Sexually Transmitted Diseases 2017; 44(2): 114-7.

Leeyaphan C…Chen M. Systematic review and meta-analysis of doxycycline efficacy for rectal lymphogranuloma venereum in men who have sex with men. Emerging Infectious Diseases 2016; 22(10): 1778-84.

Towns J...Chen M. Painful and multiple anogenital lesions are common in men with Treponema pallidum PCR-positive primary syphilis without herpes simplex virus co-infection: a cross-sectional clinic-based study. Sexually Transmitted Infections 2016; 92: 110-15.

Bissessor M...Chen M. The contribution of Mycoplasma genitalium to the aetiology of sexually acquired infectious proctitis in men who have sex with men. Clinical Microbiology and Infection 2016; 22: 260-5.

Zou H...Chen M & Fairley C. Site-specific human papillomavirus infection in adolescent men who have sex with men (HYPER): an observational cohort study. Lancet Infectious Diseases 2015; 15(1): 65-73. 

Bissessor M...Chen M. Persistence of Neissseria gonorrhoeae DNA following treatment for pharyngeal and rectal gonorrhea is influenced by antibiotic susceptibility and reinfection. Clinical Infectious Diseases 2015; 60(4): 557-63.

Bissessor M...Chen M. Detection of Neisseria gonorrhoeae from the tonsils and posterior oropharynx. Journal of Clinical Microbiology 2015; 53(11): 3624-6.

Zou H...Chen M. Early acquisition of anogenital human papillomavirus among teenage men who have sex with men. Journal of Infectious Diseases 2014; 209: 642-51.

Chen M...Hogg G. Failure of ceftriaxone 500mg to eradicate pharyngeal gonorrhoea. Journal of Antimicrobial Chemotherapy 2013; 68(6): 1445-7.

Read T...Chen M. Provision of rapid HIV tests within a health service and frequency of HIV testing among men who have sex with men: a randomised controlled trial. BMJ 2013; 347: f5086.

Zou H...Chen M. Automated computer-generated reminders and increased detection of gonorrhoea, chlamydia and syphilis in men who have sex with men. PLOS ONE 2013; 8(4): e61972. 

Bissessor M...Chen M. The etiology of infectious proctitis in men who have sex with men differs according to HIV status. Sexually Transmitted Diseases 2013; 40(10): 768-70.

Bissessor M...Chen M. Differing Neisseria gonorrhoeae bacterial loads in the pharynx and rectum in men who have sex with men: implications for gonococcal detection, transmission and control. Journal of Clinical Microbiology 2011; 49(12): 4304.

Bissessor M...Chen M. Use of a computer alert increases detection of early, asymptomatic syphilis among high risk men who have sex with men. Clinical Infectious Diseases 2011; 53(1): 57-8.

Bissessor M...Chen M. Frequent screening for syphilis as part of HIV monitoring increases the detection of early, asymptomatic syphilis among HIV positive homosexual men. Journal of AIDS 2010; 55(2): 211-16.

Bilardi J...Chen M. Let Them Know: evaluation of an online partner notification service for chlamydia that offers email and SMS messaging. Sexually Transmitted Diseases 2010; 37(9): 563-5.

Bilardi J...Chen M. Experiences and outcomes of partner notification among men and women recently diagnosed with chlamydia and their views on innovative resources aimed at improving notification rates. Sexually Transmitted Diseases 2010; 37(4): 253-8.

Chen M...Garland S. Screening pregnant women for chlamydia: what are the predictors of infection. Sexually Transmitted Infections 2009; 85: 31-5.