(P19) Diversity in sequence types of Chlamydia trachomatis and inflammatory profiles in adolescent girls and young women from Cape Town and Johannesburg, South Africa

Tuesday, July 25, 2023

16:30 – 18:00 CST

Primary Presenter(s)

Pride Kanyoka (he/him/his)

Ph.D. student
University of Cape Town
Cape Town, Western Cape, South Africa

Co-author(s)

JP

Jo-Ann Passmore, n/a

Proffessor
University of Cape Town, Institute of Infectious Disease and Molecular Medicine
Cape Town, Western Cape, South Africa
BK

Brian Kullin

Division of Medical Virology, Department of Pathology, University of Cape Town
Cape Town, Western Cape, South Africa
SD

Smritee Dabee

Seattle Children’s Research Institute
Seattle, Washington, United States
HJ

Heather Jaspan

Seattle Children’s’ Research Institute, University of Washington
Seattle, Washington, United States
HG

Hoyam Gamieldien

Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
KG

Katherine Gill

Desmond Tutu HIV Centre, University of Cape Town, South Africa
BV

Bart Versteeg

Kennisinstituut van de Federatie Medische Specialisten, Utrecht, Netherlands
RB

Rubina Bunjun

University of Cape Town, Institute of Infectious Disease and Molecular Medicine
Cape Town, Western Cape, South Africa
SB

Sylvia Bruisten

Medisch moleculair microbioloog Infectieziekten
Amsterdam, Netherlands
SB

Shaun Barnabas

Famcru (Stellenbosch University)
Cape Town, Western Cape, South Africa
EM

Etienne Muller

National Institute for Communicable Disease, South Africa
GG

Glenda Gray

Perinatal HIV Research Unit,University of the Witwatersrand
Johannesburg, Gauteng, South Africa
LB

Linda-Gail Bekker

Desmond Tutu HIV Centre, University of Cape Town, South Africa
DL

David Lewis

Sydney Institute for Infectious Diseases & Westmead Clinical School, University of Sydney, Australia

Background: Adolescent girls and young women (AGYW; < 25 years) are at highest risk for Chlamydia trachomatis (CT) infection, although the majority of CT infections in women are asymptomatic despite causing genital inflammation. Here, we investigated cervicovaginal inflammation associated with CT infections in AGYW living in two major urban centres in South Africa, using high resolution multi-locus sequence typing (hr-MLST).

Methods: AGYW (16-22 years) from Johannesburg (JHB; n=149) and Cape Town (CPT; n=149) were enrolled for either one or three visits (over 8 months), respectively. At each visit, samples were screened for CT, as well as Neisseria gonorrhoea, Mycoplasma genitalium, and Trichomonas vaginalis by multiplex qPCR. Intra-taxa diversity among CT strains was determined by hr-MLST. Cervicovaginal cytokines were measured by Luminex multiplex.

Results: CT prevalence in AGYW was 32.8% overall, significantly higher in CPT (41.6%; 62/149) than JHB (17.4%; 26/149), although CT was associated with higher genital inflammation in JHB participants than CPT (associated with significantly higher in IL-1, IL-6, TNF- and IFN-). Because of differences in CT-associated inflammation in AGYW in JHB and CPT, hr-MLST was used to evaluate sequence types (STs). From 114 CT cases (including 142 samples, some individuals had multiple visits), 31 unique and 14 novel STs (not present in the global database) were identified. The most common STs were ST12d (n=12), followed by ST530b (n=11), and ST3 (n=8). ST12d was only detected in CPT. ST530b was the most prevalent ST in JHB. Distinct cytokine profiles were associated with the three most prevalent STs: ST530b was associated with significantly higher MIG concentrations (β=0.74; p< 0·0001), while ST12d appeared to have a weaker influence on genital inflammatory responses.

Conclusion: CT prevalence was higher in AGYW in CPT than JHB, with unique STs being identified in these distinct geographies. Differing cervicovaginal cytokine profiles between sites may partially be explained by distinct STs.