Incidence of sexually transmitted infections among adolescent's men who have sex with men and transgender women enrolled in a PrEP cohort study in Brazil

Title

Incidence of sexually transmitted infections among adolescent's men who have sex with men and transgender women enrolled in a PrEP cohort study in Brazil

Presenter

Lorenza Dezanet

Authors

L. Dezanet * (1), L. Magno (1,2), F. Soares (1), V. de Jesus Salgado (3), C. Marcellus Pereira de Abreu Oliveira (3), L. Miranda Marques (3), G. Barreto Campos (3), I. Dourado (1)

Institutions

(1) Federal University of Bahia, Collective Health Institute, Salvador, Brazil, (2) State University of Bahia, Department of Life Sciences, Salvador, Brazil, (3) Federal University of Bahia, Multidisciplinary Health Institute, Vitória da Conquista, Brazil

BACKGROUND: Adolescent men who have sex with men (aMSM) and transgender women (aTGW) are disproportionately affected by HIV and other sexually transmitted infections (STI). However, studies on the incidence of STI among adolescents enrolled in PrEP are still scarce. We aimed to estimate the incidence of N. gonorrhoeae, C. trachomatis, M. genitalium, M. hominis, U. urealyticum and U. parvum among adolescents PrEP users.
METHODS: PrEP1519 is a single-arm demonstration cohort study of daily TDF/FTC as PrEP. It is ongoing in 3 Brazilian capital cities among aMSM and aTGW aged 15-19 years-old (yo), recruited from February 2019-September 2021, with the following eligibility criteria: HIV uninfected, high risk of HIV, and with no risk of kidney and liver damage. They completed a questionnaire, and swab samples from multiple sites (oropharyngeal, anal, and urethral) were provider-collected and tested for each STI by using qPCR, at PrEP initiation and weeks 4, 12, and then quarterly through week 96. For this analysis, we included participants who had a minimum of 2 consecutive visits at the Salvador site and provided a swab sample at PrEP initiation and at least one more during follow-up. Case of STI was defined as positive-qPCR from any anatomical site. STI incidence rate per person-year (PY) of follow-up and 95% confidence intervals (95%CI) were estimated.
RESULTS: At PrEP initiation, participants were mostly MSM (91%) and 18-19 yo (84%). Median age of sexual debut was 14 yo (IQR:12-16), and 56% of participants did not use or did not remember using a condom at first sexual intercourse. Incidence measures of bacterial STI after initiating PrEP in Salvador (Brazil) are presented below. The incidence of U. urealyticum was particularly high.

Total N Incident cases Sum of PY Incidence rate per 100 PY (95% CI)
N. gonorrhoeae
132 19 219.2 8.7 (5.5-13.6)
C. trachomatis
132 22 246.5 8.9 (5.9-13.6)
M. genitalium 137 11 204.5 4.6 (2.5-8.3)
M. hominis 133 19 224.3 8.5 (5.4-13.3)
U. urealyticum 128 43 186.3 23.1 (17.1-31.1)
U. parvum 137 10 253.9 3.9 (2.1-7.3)

CONCLUSIONS: Important rates of STI among adolescents in PrEP1519 indicate that innovative approaches to decrease STI incidence are much needed. Point-of-care STI testing should be an essential component to help decrease STI incidence among aMSM and aTGW PrEP users followed by appropriate STI treatment.

	Total N	Incident cases	Sum of PY	Incidence rate per 100 PY	(95% CI)
N. gonorrhoeae	132	19	219.2	8.7	(5.5-13.6)
C. trachomatis	132	22	246.5	8.9	(5.9-13.6)
M. genitalium	137	11	204.5	4.6	(2.5-8.3)
M. hominis	133	19	224.3	8.5	(5.4-13.3)
U. urealyticum	128	43	186.3	23.1	(17.1-31.1)
U. parvum	137	10	253.9	3.9	(2.1-7.3)

Download the e-Poster (PDF)