Treponemal Shedding, Load, and Viability, in Women and Men-who-have-sex-with-women-only With Early Infectious Syphilis: Implications for Transmission

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

NOT_YET_RECRUITING

Total Enrollment

480 participants

Study Classification

OBSERVATIONAL

Study Start Date

2025-12-01

Study Completion Date

2028-12-31

Brief Summary

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How syphilis is transmitted between sexual partners is unclear. Asymptomatic detection i.e. detection of syphilis bacteria (Tp) from anatomical sites without lesions, in patients with syphilis infection, suggests that asymptomatic transmission from these sites may play a role. However, no existing studies have established whether the syphilis bacteria (Tp) detected was viable. This means it is not known if the bacteria at this anatomical site is alive and therefore able to transmit the infection. Further, studies have focused mostly on men who have sex with men, resulting in a lack of evidence regarding anal shedding in men-who-have-sex-with-women only and women (regardless of sexual behaviour), and no data on asymptomatic vaginal shedding in women. This study will explore:

1. Patterns of Tp detection in women and men-who-have-sex-with-women only.
2. Whether detected Tp from each asymptomatic anatomical sites is viable
3. Duration of Tp detection and viability (alive and transmissible bacteria). Patients presenting to a participating sexual health service (overseas only) for management of suspected/confirmed early infectious syphilis will be eligible. During the routine clinical examination, participants will have additional oral and anal swabs, urine, vaginal swab (where relevant), penile skin swab (where relevant) and blood sample collected, in addition to the routine samples taken from the same sites and routine serology collected when syphilis is diagnosed.

Detailed Description

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Conditions

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Syphilis

Keywords

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syphilis sexual health syphilis transmission asymptomatic shedding

Study Design

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Observational Model Type

CASE_ONLY

Study Time Perspective

CROSS_SECTIONAL

Study Groups

No intervention: Observational study

Interventions

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No Intervention: Observational Cohort

No intervention: Observational study

Intervention Type OTHER

Eligibility Criteria

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Inclusion Criteria

\- 1. Any cis-woman, cis-MSW, or nonbinary individuals with a penis who have sex with women only, (who meet all other study criteria) 2. Aged ≥18 years of age, 3. At least one sexual partner in the last 12 months 4. One of either:

a. Untreated clinically suspected primary or secondary syphilis. i. Must have rash or lesion(s) clinically suggestive of early infectious syphilis infection.

ii. May have positive PCR result, positive Dark-ground Microscopy result, positive syphilis serology or positive point-of-care syphilis test, but these are not necessary at the time of enrolment.

b. Untreated early latent (no clinical signs indicative of primary or secondary syphilis) syphilis with positive syphilis serology or positive point-of-care test, and one or more of the following(11): i. A documented syphilis seroconversion within the prior 12 months. ii. A sustained (longer than 2 weeks) fourfold or greater increase in the titre in the prior 12 months in a person previously treated for syphilis.

iii. Unequivocal symptoms of primary or secondary syphilis within the prior 12 months.

iv. Contact in the prior 12 months with a sex partner who had untreated primary, secondary, or early latent syphilis.

v. Documented reactive nontreponemal and treponemal tests, and the only possible exposure occurred during the previous 12 months vi. RPR/VDRL titre \>= 1:64 5. Be willing and able to complete study procedures, including physical examination 6. Receiving syphilis treatment on the day of recruitment 7. Have sufficient language proficiency to understand the requirements of the study 8. Provide informed consent as per individual site's local ethics requirements

Exclusion Criteria

1. Men, transwomen, or other people, with a penis, who have had any sexual contact, including kissing, oral sex or anal sex, with men (or any other individual with a penis) in the previous one year.
2. Individuals who have received antibiotic treatment within 1 month prior to enrolment, with the EXCEPTION of metronidazole.
3. Diagnosis of late latent syphilis (\>1 year) or latent syphilis of unknown duration.

Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Janet Towns

Role: PRINCIPAL_INVESTIGATOR

Monash University

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Brigid M Scally

Role: CONTACT

Phone: +61399039300

Email: [email protected]

Janet Towns

Role: CONTACT

Email: [email protected]

Other Identifiers

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MUCTC-24018

Identifier Type: -

Identifier Source: org_study_id

Treponemal Shedding, Load, and Viability, in Women and Men-who-have-sex-with-women-only With Early Infectious Syphilis: Implications for Transmission

Study Results

Basic Information

Brief Summary

Detailed Description

Conditions

Keywords

Study Design

Study Groups

Cis-women with suspected or confirmed primary syphilis infection

No Intervention: Observational Cohort

Cis-women with suspected or confirmed secondary syphilis infection

No Intervention: Observational Cohort

Cis-women with confirmed early-latent syphilis infection

No Intervention: Observational Cohort

Men-who-have-sex-with-women-only with suspected or confirmed primary syphilis infection

No Intervention: Observational Cohort

Men-who-have-sex-with-women-only with suspected or confirmed secondary syphilis infection

No Intervention: Observational Cohort

Men-who-have-sex-with-women-only with confirmed early-latent syphilis infection

No Intervention: Observational Cohort

Interventions

No Intervention: Observational Cohort

Eligibility Criteria

Inclusion Criteria

Exclusion Criteria

Sponsors

Melbourne Sexual Health Centre

The Alfred

Monash University

Responsible Party

Principal Investigators

Janet Towns

Locations

Monash University

Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine

Shanghai Skin Disease Hospital

Foundation for Professional Development

Burrell Street Clinic, Guy's and St Thomas'

Jefferiss Clinic St Mary's Hospital, Imperial College London

Mortimer Market Centre

London School of Hygiene & Tropical Medicine

Countries

Central Contacts

Brigid M Scally

Janet Towns

Other Identifiers

MUCTC-24018