Rapid, robust, and near point-of-care saliva-based nucleic acid detection of dengue virus infections

Background:

Dengue virus (DENV) is a major global health concern, with hundreds of millions of infections occurring annually, particularly in tropical and subtropical regions. Accurate and timely diagnosis is crucial for effective patient management and for controlling outbreaks, especially since infection with one DENV serotype can increase the risk of severe disease upon subsequent infection with a different serotype. Traditionally, DENV diagnostics have relied on blood-based methods, which require trained phlebotomists, specialized equipment, and can be invasive and uncomfortable for patients. This reliance on blood samples poses significant challenges in resource-limited settings, where access to healthcare infrastructure and skilled personnel may be limited, and where rapid, large-scale testing is often needed during outbreaks. Current diagnostic approaches for DENV, such as conventional PCR and serological tests, face several limitations. Blood-based PCR assays, while sensitive, often require complex sample preparation, including RNA purification, and are susceptible to inhibitors present in crude samples, which can compromise accuracy. Serological assays, on the other hand, may not reliably distinguish between DENV serotypes or between primary and secondary infections, leading to potential misdiagnosis. Furthermore, the need for cold chain storage, specialized reagents, and laboratory infrastructure restricts the deployment of these tests in field or point-of-care settings. These challenges highlight the need for more accessible, rapid, and non-invasive diagnostic solutions that can be implemented widely, particularly in outbreak-prone and resource-constrained environments.

Technology Overview:

This technology provides a rapid, non-invasive diagnostic solution for detecting and differentiating all four dengue virus (DENV) serotypes using saliva samples. It integrates two advanced nucleic acid testing methods: a multiplex quantitative PCR (qPCR) assay and a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay. The multiplex qPCR can simultaneously identify DENV1–4 and a human internal control in under 90 minutes, with high sensitivity down to 3–5 viral RNA copies per microliter, and is compatible with both purified and crude saliva samples. The RT-LAMP assay, operating at a single temperature, delivers serotype-specific results in as little as 7–15 minutes and supports simple colorimetric or lateral-flow readouts, making it suitable for point-of-care settings. Both methods use standard commercial reagents and are designed for ease of use, eliminating the need for trained phlebotomists and enabling deployment in resource-limited environments. This technology is differentiated by its comprehensive approach to dengue diagnostics, leveraging large-scale genomic analysis to design highly specific primers and probes that ensure accurate serotype identification directly from saliva. Unlike traditional blood-based tests, this solution offers a non-invasive alternative that is easier to administer and more acceptable to patients, particularly in mass screening or pediatric contexts. The assays have been validated through rigorous human challenge studies and transcriptomic analyses, demonstrating comparable sensitivity and specificity to blood-based methods while also providing insights into host immune responses. Its compatibility with digital PCR and whole-genome sequencing further enhances its utility for research and epidemiological surveillance. The combination of rapid turnaround, high accuracy, non-invasive sampling, and adaptability to point-of-care use positions this technology as a significant advancement in global dengue management and public health diagnostics.

Advantages:

•    Non-invasive detection of all four Dengue virus serotypes using saliva samples, eliminating the need for blood draws.
•    Rapid results with multiplex qPCR providing detection in under 90 minutes and RT-LAMP assays delivering results within 7–15 minutes.
•    High sensitivity and specificity by targeting conserved, serotype-distinct genomic regions, with detection limits as low as ~3 copies/µL.
•    Compatibility with point-of-care settings due to tolerance of crude saliva inhibitors and use of standard commercial enzymes and reagents.
•    Supports multiple readout formats including fluorescent, colorimetric, and lateral-flow assays for flexible diagnostic use.
•    Enables viral RNA quantification and whole-genome sequencing directly from saliva, facilitating detailed viral analysis and surveillance.
•    Reduces reliance on trained medical personnel and specialized equipment, improving accessibility in resource-limited environments.
•    Potential to enhance understanding of host immune responses through saliva transcriptomic analysis alongside viral detection.

Applications:

•    Point-of-care dengue screening
•    Rapid outbreak surveillance
•    At-home dengue self-testing
•    Clinical trial participant monitoring
•    Travel health screening

Intellectual Property Summary:

Patent application filed: 63/924,381, filed on 11/24/2025
Know-how based

Stage of Development:

Design of highly specific primers and probes in hand, that ensure accurate serotype identification directly from saliva. TRL level 4.

Licensing Status:

This technology is available for licensing.