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. 2021 Oct 30;21(1):1123.
doi: 10.1186/s12879-021-06668-6.

Prevalence and risk factors associated with HIV and syphilis co-infection in the African Cohort Study: a cross-sectional study

Laura Gilbert  1 , Nicole Dear  2   3 , Allahna Esber  2   3 , Michael Iroezindu  2   4 , Emmanuel Bahemana  2   5 , Hannah Kibuuka  6 , John Owuoth  7   8 , Jonah Maswai  2   9 , Trevor A Crowell  2   3 , Christina S Polyak  2   3 , Julie A Ake  2 ; AFRICOS Study Group
Collaborators, Affiliations

Prevalence and risk factors associated with HIV and syphilis co-infection in the African Cohort Study: a cross-sectional study

Laura Gilbert et al. BMC Infect Dis. .

Abstract

Background: Each year, 5.6 million new syphilis cases are diagnosed globally. Guidelines for people living with HIV (PLWH) in low-income countries (LIC) recommend STI testing for symptomatic persons and those newly diagnosed with HIV; routine STI testing is less clear. Here we provide updated syphilis prevalence and identify co-infection risk factors in PLWH in the African Cohort Study (AFRICOS) to understand these rates as they relate to syndromic treatment.

Methods: AFRICOS is a study enrolling PLWH and HIV-uninfected individuals in four African countries. Participant study enrollment information was used to determine syphilis prevalence and co-infection risk factors. Inclusion criteria consisted of adults 18 years or older receiving care at a participating clinic as a long-term resident who consented to data and specimen collection. Exclusion criteria consisted of pregnancy and/or imprisonment. Screen-positive syphilis was defined as a reactive rapid plasma regain (RPR) upon study enrollment whereas confirmed syphilis included a reactive RPR followed by reactive treponemal test. Multivariate analyses was performed to determine HIV and syphilis co-infection risk factors.

Results: Between 2013 and March 1, 2020, 2939 PLWH enrolled and 2818 were included for analysis. Screen-positive and confirmed syphilis prevalence were 5.3% (151/2818) and 3.1% (87/2818), respectively. When the analysis was restricted to PLWH with an RPR titer of greater than, or equal to, 1:8, 11/87 (12.6%) participants were included. No PLWH and confirmed syphilis had documented genital ulcers. In the multivariate model, participants with confirmed syphilis co-infection were more likely to have none or some primary education [aOR 3.29 (1.60, 6.74)] and consume alcohol [aOR 1.87 (1.16, 3.03)] compared to those without syphilis. Antiretroviral therapy (ART) with suppressed viral load (VL) was protective in the unadjusted model but not adjusted multivariate model.

Conclusions: Our findings show that syphilis rates in sub-Saharan Africa remain elevated where diagnosis remains challenging, and that both lower education level and alcohol consumption are significantly associated with HIV/syphilis co-infection in AFRICOS. Based on our analysis, current STI guidelines targeting testing for African individuals with either new HIV diagnosis or syndromic symptoms may be inadequate, highlighting the need for increased testing and treatment strategies in resource-limited settings.

Keywords: Africa; Human immunodeficiency virus (HIV); Syphilis.

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Conflict of interest statement

The authors declare that they have no competing interests. The views expressed are those of the authors and should not be construed to represent the positions of the U.S. Army or the Department of Defense or the Department of Health and Human Services. LG: I am a military service member. This work was prepared as part of my official duties. Title 17 U.S.C. 105 provides that “Copyright protection under this title is not available for any work of the United States Government.” Title 17 U.S.C. 101 defines a United States Government work as a work prepared by a military service member or employee of the United States Government as part of that person’s official duties.

References

    1. Newman L, Rowley J, Hoorn VS, et al. Global estimates of the prevalence and incidence of four curable sexually transmitted infections in 2012 based on systematic review and global reporting. PLoS Negl Trop Dis. 2015 doi: 10.1371/journal.pone.0143304. - DOI - PMC - PubMed
    1. WHO: Global health sector strategy on sexually transmitted infections 2016–2021 towards ending STIs. https://www.who.int/reproductivehealth/publications/rtis/ghss-stis/en/; 2016.
    1. Kojima N, Klausner J. An update on the global epidemiology of syphilis. Curr Epidemiol Rep. 2018;5(1):24–38. doi: 10.1007/s40471-018-0138-z. - DOI - PMC - PubMed
    1. Kalichman SC, Pellowski J, Turner C. Prevalence of sexually transmitted coinfections in people living with HIV/AIDS: systematic review with implications for using HIV treatments for prevention. Sex Transm Infect. 2011;87(3):183–190. doi: 10.1136/sti.2010.047514. - DOI - PMC - PubMed
    1. Magri F, Donà MG, Panetta C, Pontone M, Pimpinella F, Cameli N, Cristaudo A, Zaccarelli M, Latini A. Unusual clinical manifestation and challenging serological interpretation of syphilis: insights from a case report. BMC Infect Dis. 2021;21(1):521. doi: 10.1186/s12879-021-06199-0. - DOI - PMC - PubMed