New Diagnostic Tool Enhances Global Surveillance of Strongyloidiasis

Liverpool, UK – May 31, 2025:
Scientists at the Liverpool School of Tropical Medicine (LSTM) have unveiled a groundbreaking diagnostic test that promises to revolutionize the global surveillance and management of strongyloidiasis, a neglected tropical disease affecting millions worldwide.

A Precision Breakthrough

The new duplex real-time PCR (rtPCR) assay, detailed in The Journal of Infectious Diseases, can accurately distinguish between two closely related threadworm species:

• Strongyloides stercoralis – the primary cause of human strongyloidiasis

• Strongyloides fuelleborni fuelleborni – a parasite mainly found in non-human primates but increasingly implicated in zoonotic (animal-to-human) transmission

Until now, most molecular tests could not differentiate between these species, leading to potential misdiagnosis and underreporting, particularly of zoonotic cases.

How the Test Works

The rtPCR test targets mitochondrial DNA, allowing for species-level identification from clinical samples. In laboratory trials, the assay demonstrated high specificity and sensitivity. When used on 96 clinical samples from the UK and Italy, it identified:

• 36 cases of S. stercoralis

• 17 cases of S. f. fuelleborni

• 2 cases of coinfection

Impacts for Public Health

Lead author Dr. Lucas Cunningham emphasized the significance:

“This new rtPCR fills a critical gap in our diagnostic toolkit. By improving species-level resolution, we can better monitor zoonotic transmission and target interventions more effectively, particularly in settings where both humans and non-human primates are involved in transmission cycles.”

The researchers recommend a two-step diagnostic protocol:

1. Initial screening with a broad test for the Strongyloides genus

2. Species confirmation using the new rtPCR assay

This approach is expected to improve detection of both imported and locally acquired infections, especially in non-endemic countries where strongyloidiasis often goes undiagnosed.

Looking Ahead

Professor Russell Stothard, co-author and medical parasitologist at LSTM, noted:

“Over the next year we are encouraging scale-up use of this diagnostic assay in routine disease surveillance in the UK and overseas to gain a much better insight into travel-related infections and improve local public health advice.”

The study also sets a precedent for developing similar diagnostics for other neglected tropical diseases with zoonotic potential.

Reference:
Lucas J Cunningham et al, Improving Molecular Epidemiological Surveillance of Strongyloidiasis Upon Differentiation of Strongyloides fuelleborni fuelleborni From Strongyloides stercoralis, The Journal of Infectious Diseases (2025). DOI: 10.1093/infdis/jiaf237

Disclaimer:
This article summarizes findings from recent scientific research. The new diagnostic tool is currently recommended for use in research and surveillance settings and may not yet be available in routine clinical practice. For medical advice or diagnosis, please consult a qualified healthcare professional.