This study evaluated the diagnostic performance of the Pluslife RHAM test, an extraction-free RNase HII-assisted amplification assay, against diagnostic real-time PCR. The analysis included 206 clinical specimens collected from patients with monkeypox, encompassing lesion swabs, oropharyngeal swabs, rectal swabs, urine, semen, and wound exudate. Testing was conducted at the German Consultant Laboratory for Poxviruses.
The primary outcome measured diagnostic sensitivity and specificity. The Pluslife RHAM test achieved a sensitivity of 94.2% (95% CI: 85.8-98.4%) and a specificity of 100% (95% CI: 97.3-100%). Sensitivity was 100% in samples with higher viral loads, defined as Ct values less than 30. The assay successfully detected all four monkeypox virus clades (Ia, Ib, IIa, IIb) and demonstrated no cross-reactivity to other poxviruses or clinically relevant pathogens.
Safety and tolerability data were not reported, as adverse events, serious adverse events, discontinuations, and tolerability metrics were not applicable or observed in this diagnostic evaluation. The study did not report limitations, funding sources, or conflicts of interest. Given the observational nature of diagnostic accuracy studies, these findings support the utility of the test but should be interpreted within the context of the specific laboratory setting and sample types evaluated.
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Mpox poses an ongoing global public health threat, with case numbers rising beyond traditionally endemic regions in Central and Western Africa. Rapid detection of the causative agent, the Monkeypox virus (MPXV), is critical for outbreak control, yet laboratory infrastructure and trained personnel remain scarce in many affected areas. Point-of-care molecular diagnostics offer a practical solution by enabling timely testing without specialized equipment or elaborate nucleic acid extraction. We evaluated the performance of an extraction-free RNase HII-assisted amplification (RHAM) assay for MPXV detection by Pluslife Biotech, a novel isothermal amplification technology providing results in under 30 minutes. The Pluslife RHAM test demonstrated pan-MPXV clade reactivity, detecting all four MPXV clades (Ia, Ib, IIa, IIb) with high analytical sensitivity and no cross-reactivity to other poxviruses or other clinically relevant pathogens. The assay proved compatible with diverse clinical specimen types, including lesion swabs, oropharyngeal swabs, rectal swabs, urine, semen, and wound exudate. As part of routine diagnostics at the German Consultant Laboratory for Poxviruses, in a comprehensive evaluation of 206 clinical specimens against diagnostic real-time PCR, the Pluslife RHAM test achieved a diagnostic sensitivity of 94.2% (95% CI: 85.8-98.4%) and a specificity of 100% (95% CI: 97.3-100%). Notably, samples with higher viral loads (Ct <30) showed 100% sensitivity. Time-to-result correlated significantly with viral load, enabling faster diagnosis in high-viral-load cases. The Pluslife RHAM test represents a practical, sensitive, and rapid point-of-care solution for MPXV detection in resource-limited settings, combining strong analytical performance with operational simplicity to support timely outbreak response and clinical decision-making.