Monkeypox virus detection in non-skin matrices: potential One Health implications

Background: Monkeypox virus (MPXV) is transmitted to humans through contact with infected live or dead animals, through bites or scratches, preparation of bushmeat, and direct contact with body fluids, lesions, or contaminated material. Given the resonance that MPXV had globally since the 2022 pandemic, early identification of infection cases is of paramount importance to prevent the viral spread to human and non human animals through contaminated.The objective of this study was to assess the presence and persistence of MPXV in matrices other than skin to identify possible pathways of spread to reservoir animal species through environmental contamination. to environment. Methods: Sixty nine patients tested positive to MPXV in the Unit of Microbiology of the Sant' Orsola Hospital and in the Unit of Microbiology of the Greater Romagna Hub Laboratory (Emilia Romagna Region, Italy) during the period from May to September 2022. Diagnosis was based on MPXV DNA identification in vesicle swabs. Non-skin specimens were collected from patients: oropharyngeal swab, urine, plasma, serum, semen, and blood. Consequent to positivity in vesicle swab, analyses on additional matrices was performed to confirm MPXV presence. Samples were extracted using the NucliSENS easyMAG automated extractor (bioMérieux) and then analysed using a home-made SYBR Green Real-Time PCR designed on A4L gene with a calculated sensitivity of 10-6 copies/ml. Results: Overall, 226 samples were collected and analysed: 45 oropharyngeal swab, 37 blood samples, 59 urines, 54 plasmas, 27 sera, 3 sputum and 1 semen. We identified 144 (56%) positive samples (Table1). Oropharyngeal swab proved to be the best alternative to the vesicle samples, with a rate of positivity of 78%, followed by urine (49%), serum (48%), plasma (44%) and blood (19%). Sputum and semen were analysed only for 4 patients showing 100% positivity. Conclusions: The results of our study confirm the importance of matrices other than vesicular material in the diagnosis of MPXV. Amongst the 69 patients, 12 were tested on all matrices and in none of them all pathological samples tested positive showing different replicative success in different compartments during infection causing intermittent viral spread. In our previous paper, we showed that the virus can persist after recovery in non-skin matrices with implications on disease control. Given the high persistence of MPXV in the environment, and recent human to dog transmission it is critical to consider the risk of spread through environment via highly infected matrices. This study, performed on a wider patients’ sample, confirms urine as a potential vehicle for environmental contamination and transmission to other animal species. Patients’ follow-up based on analysis of non-skin samples has the significance of assessing the risk of infection to humans and non-human animals. based on the One Health principle of shared risks and interspecies solidarity