A multicentre clinical study demonstrates high concordance between the Affirm VPⅢ Chip Assay and gold-standard reference methods for the simultaneous detection of Bacterial Vaginosis, Vulvovaginal Candidiasis and Trichomonas Vaginalis in routine vaginal secretion testing.
Vaginal infections represent one of the most common reasons women seek primary care and gynaecological consultations worldwide. Despite their prevalence, accurate first-visit diagnosis remains challenging: conventional microscopy is operator-dependent, gold-standard culture methods require 24–72 hours, and many clinics lack the equipment or expertise to perform both tests concurrently. The Affirm VPⅢ Chip Assay addresses this diagnostic gap with a rapid, automated, multi-target nucleic acid hybridisation platform.
Study Design and Patient Population
The clinical validation study enrolled women presenting with symptoms of vaginal discharge, odour or discomfort at multiple gynaecology outpatient departments across China. For each enrolled patient, vaginal swab specimens were collected and tested simultaneously by three methods: the Affirm VPⅢ Chip Assay, conventional wet mount microscopy, and pathogen-specific culture or gold-standard reference testing (Nugent Score / Amsel criteria for BV; culture for VVC and TV).
Results were compared to establish sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each pathogen and each testing method.
Clinical Performance Results
The study demonstrated that Affirm VPⅢ consistently outperformed conventional microscopy in sensitivity for all three target pathogens while maintaining high specificity:
- Bacterial Vaginosis (BV): Affirm VPⅢ achieved 93.55% sensitivity and 83.15% specificity vs. Nugent Score / Amsel criteria — compared to 51.61% sensitivity for Amsel criteria alone
- Vulvovaginal Candidiasis (VVC): Sensitivity of 89.4% and specificity of 98.3% vs. culture reference — significantly superior to microscopy (76.9% sensitivity)
- Trichomonas Vaginalis (TV): Sensitivity of 92.86% and specificity of 100% vs. culture reference — compared to microscopy sensitivity of 78.57%
“Affirm VPⅢ consistently outperforms conventional microscopy in sensitivity for all three pathogens, while maintaining high specificity — making it the clinically superior choice for accurate first-visit diagnosis and appropriate treatment selection.”
Clinical Implications
The ability to simultaneously detect three pathogens from a single specimen in under one hour has significant practical implications for gynaecological outpatient practice:
- Eliminates misdiagnosis arising from empirical, symptom-based treatment without laboratory confirmation
- Identifies mixed infections (which are present in approximately 20–30% of symptomatic cases) that are frequently missed by single-pathogen testing approaches
- Enables targeted, evidence-based antibiotic or antifungal prescribing from the first consultation, reducing inappropriate antimicrobial use
- Streamlines outpatient workflow — results available within the same consultation, avoiding a second appointment for culture results
- Reduces recurrence rates by ensuring all infecting organisms are identified and treated concurrently
Regulatory Status and Availability
The Affirm VPⅢ System has received CFDA (now NMPA) registration in China and is cleared for use in clinical laboratories across mainland Chinese healthcare institutions. It requires no special laboratory environment, making it well-suited for use in OB/GYN outpatient departments, community health centres and maternal and child health hospitals.
Hong Kong Origins Investment Limited distributes the Affirm VPⅢ System to healthcare institutions across the Greater Bay Area and provides full support including installation, training and ongoing technical service. To enquire about pricing and availability for your institution, please contact our team.