In a recent study published in The Lancet Public Health, researchers performed a meta-analysis on the utility of syphilis self-testing (SST).
Study: The role of syphilis self-testing as an additional syphilis testing approach in key populations: a systematic review and meta-analysis. Image Credit: JarunOntakrai/Shutterstock.com
Background
Syphilis, a sexually-transmitted Treponema pallidum infection, is a worldwide epidemic that predominantly affects males having sexual intercourse with males (MSM), sex workers, and transgender women.
Access to healthcare facilities is hampered by economic, structural, and social constraints, leading to delayed identification and management of syphilis, continuing spread, and increasing infection-associated morbidity and mortality.
Discrimination, stigma, prior negative healthcare experiences, gender-based abuse, confidentiality concerns, reluctance to reveal sexual behavior, and limited accessibility to health facilities all contribute to sexually transmitted diseases (STD) follow-up losses and low testing rates.
SST has the potential to expand testing and therapy coverage similarly as self-tests for human immunodeficiency virus (HIV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and hepatitis C virus (HCV) have been shown to do.
About the study
In the present meta-analysis, researchers reviewed the scientific evidence on SST concerning its usability, accuracy, acceptability, reactivity, uptake, association with confirmatory testing, management, care services for sexual health, adverse events or social harm, cost-effectiveness, and execution factors.
Databases such as Embase, MEDLINE, Scopus, Web of Science, and CINAHL were searched for studies published between January 1, 2000, and October 13, 2022. Original research on rapid tests for syphilis, including dual syphilis-HIV testing, was included.
In addition, four electronic STD or HIV conference databases [conferences of the International acquired immunodeficiency syndrome (AIDS) Society, United States Centers for Disease Control and Prevention (US CDC), International Union Against STDs, and Retroviruses and Opportunistic Infections] were reviewed.
The World Health Organization (WHO) research group for human immunodeficiency virus self-testing guidelines’ updates provided data on syphilis-HIV dual testing.
Two researchers independently performed data screening and extraction, and discrepancies were resolved by a third researcher. Random-effects modeling was performed to determine the pooled percentage of individuals offered syphilis self-testing kits who underwent testing.
Bias risks were analyzed using Cochrane’s Risk of Bias Tool and the Johanna Briggs’ Institute (JBI) Critical Appraisal Tool for randomized controlled trials (RCTs) and non-RCTs, respectively, and certainty of evidence using the GRADE approach. SST includes tests performed by individuals who collect specimens, perform the tests, and interpret the results. Descriptive statistics were used to summarize study characteristics.
Results
In total, 40,499 records were identified, of which 11 were eligible, including seven studies conducted in the United States of America (USA, one study), China (five studies), and Zimbabwe (one study). Among the included studies, two recruited individuals from 2015 to 2017 and nine recruited individuals from 2018 to 2020.
Four studies documented data from MSM individuals, and five utilized dual SST-HIV dual tests. All the included cross-sectional analytical studies had low bias risks. Regarding evidence certainty, the team found very low evidence certainty for adverse events and social harm; low confidence for reactivity, usability, and linkage to treatment and care; and high certainty for uptake.
Using information from three observational-type studies and one RCT, the pooled percentage of individuals who underwent SST testing was 88.0%, with medium-level heterogeneity in the study findings (I² of 46.0%). None of the studies provided information on SST specificity or sensitivity.
Provider and user SST preferences were high, with SST facilitators including privacy, convenience, autonomy, quick results, reduced contact with health facilities, time savings, and trust in hematological testing, with individuals capable of self-testing correctly.
Studies conducted in China reported the highest uptake rates (approximately 90%) and that SST was more cost-effective at an individual level than facility-based tests.
However, there were a few reported challenges, including finger prick requirements for blood sample collection, complicated and lengthy procedures (involving removal of test components from the package, pipetting buffer, and understanding SST instructions), technical problems related to phone use (e.g., SST scanning), and result interpretation difficulties.
SST implementation barriers included lack of knowledge (including SST unawareness and kit and care accessibility locations), sample collection and result interpretation challenges, poor STD awareness, and privacy, cost, and test accuracy concerns.
A study reported that 30 out of 174 males and nine out of 76 female sexual workers were pressured to perform SST due to verbal abuse, relationship termination, violent threats, and psychological pressure.
Conclusion
Overall, the study findings expand on self-testing data for various disease locations and show that SST can reach neglected individuals.
SST implementation proved possible and acceptable; hence, SST may be utilized as a supplementary syphilis testing strategy.
However, since SST specificity and sensitivity data were unavailable, further research is required to develop appropriate strategies and policies for delivering and scaling SST.