Detection of Mpox and other Orthopoxviruses using a Lateral Flow Device as a Point of Care diagnostic

Abstract

In 2022 the WHO declared the worldwide outbreak of mpox to be a public health emergency of international concern (PHEIC). The causative monkeypox virus (MPXV) belonged to Clade IIb and transmitted through sexual contact with a low case fatality rate (0.1%), which together with underdetection, all contributed to a rapid global spread particularly within the MSM (men who have sex with men) community. As MPXV Clade II remains circulating worldwide, a new outbreak of the more fatal Clade I disease has been declared in Central and East Africa and remains uncontrolled in part due to the lack of Point of Care (POC) diagnostics for rapid decisions on treatment and self-isolation. Aim: To address the lack of POC solutions for mpox we have designed and evaluated an orthopoxvirus-specific lateral flow device (LFD) that could be used for diagnosis of mpox. Results: Using an LFD comprising four monoclonal antibodies against the A27 protein we demonstrate sensitivity to 3x105pfu/ml. This sensitivity is expected to be sufficient for detection of MPXV from lesion sites and may also be sufficient for other sample types such as saliva and urine. However, sample collection buffer may have a detrimental impact on sensitivity for clinical material. Conclusion: Point of care (POC) diagnosis of mpox may be possible using a LFD to reduce delays arising from sample shipment to centralised laboratory testing facilities.