When performed as part of a Centers for Disease Control and Prevention (CDC)-approved syphilis testing algorithm, the VITROS Syphilis Assay may be able to detect syphilis infections early in the disease lifecycle when nontreponemal tests might not yet be reactive.1
The infection is caused by the bacterium Treponema pallidum and usually spreads through sexual contact but can be transmitted from mother to baby during pregnancy or at birth, resulting in congenital syphilis or by the transfusion of infected blood.
Each of the four stages - primary, secondary, latent and tertiary - produce diverse clinical symptoms, typically with initial chancres, then syphilitic rash, followed by long periods of dormancy and may lead eventually to cardiovascular disease, mental disease, blindness, neurosyphilis and even death.1
Syphilis is 100% curable with appropriate antibiotic treatment, typically using penicillin, which effectively eliminates the bacterium from the body. Early diagnosis and treatment are crucial - the sooner syphilis is treated, the less likely it is to cause serious health complications.
Syphilis cases at highest levels in 70 years in an alarming trend2
Syphilis cases increased 80% between 2018 and 2022, making it a nation-wide epidemic. Syphilis cases in the U.S. have reached approximately 150,000 annually.3 The increase is driven by factors such as higher rates of unprotected sexual activity, inadequate screening and treatment, barriers to healthcare access, and social factor4
Congenital syphilis among newborns rose 183% between 2018 and 2022 and around 300% over the last decade.6 There are approximately 1,000 cases of congenital syphilis reported each year in the U.S. This increase reflects the overall increase in syphilis among women of reproductive age. It has been reported that every 2 in 5 babies born to women with untreated syphilis result in death.5
2 in 5 babies born to women with untreated syphilis die from the infection5
New laboratory recommendations for syphilis testing
The CDC released in February 2024 recommended use of the reverse algorithm in the primary screening approach of syphilis testing.
This method involves initially using a highly sensitive treponemal test (such as an enzyme immunoassay) followed by a more specific non-treponemal test (like the Rapid Plasma Reagin or RPR) for confirmation if the initial test is positive.
The reverse algorithm helps improve diagnostic accuracy by reducing false positives and ensuring that confirmatory testing is aligned with the initial screening results.7
Screening of pregnant women with the VITROS Syphilis Assay is important to reduce the spread of congenital syphilis.9
Syphilis is a serious infection that can be passed to a fetus during pregnancy and cause lifelong health issues or death for the baby.
In 2022, the CDC reported that more than 3,700 babies were born with congenital syphilis, which was more than 10 times the number in 2012.
- Syphilis poses significant prenatal risks because if a pregnant person is infected, the bacteria can be transmitted to the baby, leading to congenital syphilis, which can cause severe health issues or even stillbirth.
- Regular screening and prompt treatment during pregnancy are essential to prevent transmission and protect both the parent and the baby.
- Increased awareness and access to prenatal care can help reduce the incidence of congenital syphilis and improve maternal and infant health outcomes.
ACOG Guidelines state that clinicians should screen all pregnant women for syphilis at the first prenatal care visit, followed by universal rescreening during the third trimester and again at birth.9
ACOG also recommends a prenatal testing panel including rubella, hepatitis B, hepatitis C and HIV. All recommended prenatal testing assays are available on VITROS systems.10
U.S. Preventive Services Task Force (USPSTF) recommends syphilis screening for these high-risk groups8:
- Men who have sex with men (MSM)/persons engaging in high-risk sexual behavior
- Commercial sex workers/persons exchanging sex for drugs
- Adults in correctional facilities
- Persons diagnosed with other STIs
- Pregnant women
Specifications
| Highly competitive analytical/operational performance | |
Time to first result | 34 min |
On analyzer stability | ≤12 weeks |
Positive percent agreement (PPA) | 98.81% |
Negative percent agreement (NPA) | 99.25% |
Sample type | Serum or plasma |
Sample volume | 25 µl |
Sample stability | 7 days at RT, 7 days at 2-8°C, 28 days at -20°C |
Calibration interval | 28 days |
