Concomitant Syndromic Diagnosis of Mpox and Other Vesicular Viruses in Patients with Skin and Genital Lesions

Abstract

The recent multi-country outbreak of the zoonotic monkeypox virus (MPXV) infection in humans without an epidemiological link with endemic areas has raised concerns about the route of transmission. Since the infection spread largely among men who have sex with men who, in most cases, presented primary lesions of the genital and oral mucosa, sexual transmission has been proposed. In the present study, we retrospectively evaluated specimens of vesicular lesions collected from the skin and genital tract of 35 patients (23 positive and 12 negative) presenting at our Institute for monkeypox (mpox) diagnosis by using a novel molecular syndromic vesicular virus panel (VVP) assay. All MPXV-positive samples but one was confirmed; however, the viral syndromic analysis revealed that 8.6% of them were coinfected with one or more viruses, and 17% had at least a virus different from the MPXV. The percentage of coinfections increased to more than 25% when nonviral pathogens, such as gonorrhea and syphilis, were also considered. These results show the usefulness of syndromic diagnosis in cases where MPXV is suspected (and vice versa) and at the same time highlight that the broader screening of sexually transmitted infections in the population with high-risk sexual behavior is critical to ensure a complete etiology and appropriate treatment.

Keywords: mpox; sexual transmission; syndromic diagnosis; vesicular lesions.

Figure 1

Comparison of cycle threshold (Ct) values obtained with virus-specific real-time PCR (rtPCR) and vesicular virus panel (VVP) test: (A) monkeypox virus DNA (MPXV DNA) detection; (B) other vesicular viruses’ genome (viral DNA/RNA) detection: varicella zoster virus (VZV), enterovirus (EV), herpes simplex virus 1 (HSV1), herpes simplex virus 2 (HSV2), and human herpes virus 6 (HHV6). Ct comparison was performed using the Wilcoxon test; p-values are indicated in each panel. Dot lines represent the limit of the detection of the molecular assays.