English
More than 1 million sexually transmitted infections (STIs) are acquired every day, and over 374 million new infections occur annually.2 At the same time, HIV, viral hepatitis, and other STIs collectively contribute to approximately 2.5 million deaths each year, underscoring the urgent need for more effective surveillance and modern diagnostic strategies.1
The expanding role of laboratories in STI surveillance
STI control is entering a new phase, where laboratory diagnostics are no longer just confirmatory tools, but central drivers of surveillance and public health action.3 HIV, hepatitis B virus (HBV), and syphilis continue to pose persistent challenges, and their evolving epidemiology demands faster, more precise, and more scalable diagnostic strategies. Serological testing remains foundational, but its role is expanding as laboratories integrate advanced algorithms, workflow automation, and data connectivity.
HIV diagnostics: Improving early detection
For HIV, fourth-generation serological immunoassays have transformed early detection by simultaneously identifying p24 antigen and antibodies. This reduces the diagnostic window and enables earlier case identification compared with antibody-only tests.4 From a surveillance perspective, earlier detection directly improves estimates of incidence and transmission patterns, which informs targeted interventions leading to improved patient outcomes.
Syphilis diagnostics: Reverse algorithm enables scalable screening
In 2025, the World Health Organization (WHO) set a goal of reducing syphilis and gonorrhea infections by 90% by 2030.5 Syphilis diagnostics highlight the importance of algorithm design in laboratory practice. In 2022, the WHO estimated that “150,000 early fetal deaths and stillbirths, 70,000 neonatal deaths and 55,000 preterm or low-birthweight births” were caused by congenital syphilis alone.5 The shift from traditional algorithms (non-treponemal screening followed by treponemal confirmation) to reverse screening algorithms (treponemal screening first) reflects both technological advances and workflow realities.6,7 High-throughput treponemal immunoassays enable efficient screening at scale. Due to shared transmission routes and risk factors, there has been an increase in the global incidence of HIV and syphilis coinfections,8 making co-testing essential.9
HBV diagnostics: From detection to interpretation
Hepatitis B virus (HBV) diagnostics present a different but equally complex landscape.5 Serological markers—including HBsAg, anti-HBs, and anti-HBc (detecting IgG and/or IgM antibodies)—provide a layered view of infection status, immunity, and exposure history. The challenge lies not in detection alone, but in interpretation. Laboratories play a critical role in structuring testing panels and reporting formats that distinguish acute infection, chronic carriage, resolved infection, and vaccine-induced immunity. As screening expands in both clinical and public health settings, automated, high-throughput immunoassay platforms allow laboratories to scale testing without sacrificing consistency.10 This standardization is essential for comparable surveillance data across regions and populations.
Why is a high-positive algorithm* important in HBV testing?
A high-positive algorithm plays an important role in making testing both efficient and clinically effective. Our validated HBsAg high-positive algorithm eliminates the need for repeat and confirmatory testing for samples ≥100.00 S/CO (signal-to-cutoff ratio) while delivering accurate results. This can help support:
- Time savings
- Reduced testing costs
- Faster results
- Higher confidence in results classification
Seeing the larger picture with laboratory information systems
Across all three infections, a common trend is the increasing integration of diagnostics with surveillance infrastructure. Laboratory information systems (LIS) are becoming active contributors to public health by enabling automated reporting, real-time data sharing, and trend analysis. This connectivity allows health authorities to detect outbreaks earlier, monitor treatment outcomes, and identify gaps in care. However, it also places new demands on laboratories to maintain data quality, standardize coding, and ensure interoperability.
Applying Advantaged Workflows to STI diagnostics
As the global need for STI testing and surveillance remains high, laboratories must find new ways to meet this demand without sacrificing efficiency or accuracy. Our philosophy of Advantaged Workflows is designed to help organizations do exactly this—with the right balance of streamlined operations and clinical precision. With assays and instruments designed for both efficiency and accuracy, laboratorians can answer the call for greater STI diagnostics with confidence. Learn more about Advantaged Workflows here.
Key takeaway: For better STI control, laboratories must go beyond detection
HIV, HBV, and syphilis each present distinct diagnostic challenges, but their paths forward are consistent: using serology not just to detect disease, but to generate actionable insights.
To modernize STI surveillance, laboratories must take a proactive role in deeply integrating diagnostics as part of a public health strategy. With guideline-driven serologic algorithms for HIV, syphilis, and HBV, laboratorians can enable accurate diagnosis, staging, and timely intervention—transforming laboratory testing into clinically actionable insights to help improve both patient care and public health outcomes.
Learn more
In the webinar, Modernizing STI Surveillance and Diagnostics: Laboratory-Driven Strategies for a Changing Public Health Landscape, Jeffrey Klausner, MD, MPH discussed the role of the diagnostic laboratory in STI testing.
Learn more and receive one CE credit. Watch the webinar available on demand here.
*The HBsAg high-positive algorithm streamlines laboratory operations by identifying samples with highly elevated surface antigen signals (S/CO ≥ 100.00). Because these high results reliably indicate true HBsAg positivity, time-consuming repeat and confirmatory neutralization testing can be bypassed. Clinicians can then immediately pivot to staging the infection, using markers like anti-HBc IgM to differentiate between acute and chronic infection, and proceed to treating the patient with minimal delay.
