RAPID EMERGENCE OF A NEW GLOBAL HEALTH CONCERN: MONKEYPOX VIRUS OUTBREAK IN BARCELONA, SPAIN

Abstract

Intro: In mid-May 2022,a monkeypox virus(MPXV) outbreak was identified in the UK,reporting new cases later in Portugal and Spain,and recently being declared a public health emergency by the WHO. The aim of this study was to describe the microbiological characteristics of MPXV infection in Barcelona. Methods: Clinical samples from patients with MPXV infection suspicion attended at Hospital Universitari Vall d'Hebron (HUVH) and Barcelona's primary healthcare centres were collected from May to July 2022. Laboratory-confirmation was initially performed by an in-house Orthopoxvirus RT-PCR assay until June,when commercial LightMix Modular Orthopoxvirus or MPXV-specific RT-PCR assays(RocheApplied Science,Germany)were available. Findings: A total of 802 samples from 511 patients were included. MPXV was laboratory-confirmed in 77.3%(395/511)of cases, 20.4%(104/511) were negative, while the remaining 2.3%(12/511) were unconclusive probably due to inhibitions or low-quality samples. Most confirmed cases were male patients(97.7%;n=386/395) and the median age was 37 years(IQR:31-44). Weekly MPXV incidence constantly increased. Discussion: The MPXV incidence trends reveal a high burden. Secondary related cases are expected when wide circulation occurs into the community. Samples from skin lesions had the best diagnostic performance;genital-chancre,throat and rectal samples also revealed higher viral loads, suggesting active viral replication and source of infection.Urine samples were positive but showing lower viral loads. Conclusion: The 2022 MPXV outbreak has had a high burden in Barcelona.Skin specimens seem to be the sample of choice for diagnosis.Even though MPX pathogenesis in humans is not still well-defined,viral replication seems to occur in oral,genital and rectal mucosa,suggesting a source of infection and playing a role in transmission,in contrast with other fluids like urine.These results are key information for prevention measures.