Microplastics as the potential reservoir and carrier of viral pathogens detected from hospital sewage.

Microplastics are pervasive pollutants that may provide surfaces for microbial colonization, yet their role in viral persistence within wastewater remains unclear. This current study investigated the possible roles of microplastics as an adsorption surface for viral pathogens isolated from hospital sewage. Sewage samples were collected weekly from a hospital wastewater treatment plant over a period of six weeks. Microplastics were isolated and characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and polymer analysis. Microplastics and sewage water were separated, and multiplex qPCR was performed, after nucleic acid extraction. Seventeen pathogenic viruses were analyzed. Descriptive analysis and principal component analysis were performed. SEM revealed rough, weathered surfaces and biofilm colonization on microplastic particles with fibers showing greater viral adsorption than fragments. Polymer analysis identified polyethylene terephthalate (PET), polypropylene (PP), and polyamide (PA). Using multiplex qPCR, genetic materials of ten viral pathogens across six families were detected on the microparticles including Adenovirus (ADV) and Norovirus genogroups (NVG1, NVG2). Notably, the microplastic particles carried Norovirus 1 and Parainfluenza virus 1 and 2, while treated sewage water did not carry these viruses. Suggesting that microplastics are significant reservoirs and carriers for viral pathogens isolated from hospital sewage.