Fluorescent Immunochromatographic Assay (FICA) for Monkeypox Virus

Monkeypox, a rare zoonotic disease classified as a category B infectious disease, is caused by the monkeypox virus (MPXV), which has a broad host range. Since May 2022, human MPXV infection outbreak has spread to more than 100 countries, and China has reported 106 MPXV infections between June 2 and 30, 2023. Therefore, rapid and effective MPXV detection is essential to control and prevent its transmission. In this study, a rapid, cost-effective, and convenient fluorescent immunochromatographic assay (FICA) for MPXV antigen A35R detection was developed. Under the optimal reaction conditions, the visual detection limit of the proposed assay was 7.5 ng/mL and was completed within 15 min. There was no cross-reactivity with norovirus (NV) or dengue virus (DENV) controls. Additionally, the clinical application of the proposed method was demonstrated by testing human serum samples spiked with the MPXV antigen A35R. FICA was faster and more convenient than traditional enzyme-linked immunosorbent assays (ELISA) or polymerase chain reaction (PCR), and hence suitable for the early screening of MPXV infection. In summary, FICA could realize rapid, low-cost, sensitive, and specific MPXV detection hold potential application prospects in clinical settings.