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. 2023 Feb:159:105372.
doi: 10.1016/j.jcv.2022.105372. Epub 2022 Dec 26.

Alternative sampling specimens for the molecular detection of mpox (formerly monkeypox) virus

Jasmine Coppens  1 , Fien Vanroye  1 , Isabel Brosius  1 , Laurens Liesenborghs  1 , Saskia van Henten  1 , Thibaut Vanbaelen  1 , Stefanie Bracke  1 , Nicole Berens-Riha  1 , Irith De Baetselier  1 , Chris Kenyon  1 , Patrick Soentjens  1 , Eric Florence  1 , Johan Van Griensven  1 , Kevin K Ariën  2 , Bart K M Jacobs  1 , Dorien Van den Bossche  1 , Marjan Van Esbroeck  1 , Koen Vercauteren  3 ; ITM MPX study group
Collaborators, Affiliations

Alternative sampling specimens for the molecular detection of mpox (formerly monkeypox) virus

Jasmine Coppens et al. J Clin Virol. 2023 Feb.

Abstract

Background: Mpox (formerly monkeypox) is a viral disease caused by the mpox virus (MPXV), endemic in Central and West Africa and currently causing a global outbreak of international concern. Much remains unknown about sample types most suited for mpox laboratory diagnosis. While it is established that high viral loads can be found in active skin lesions (currently the recommended mpox laboratory confirmation specimen type), WHO mpox testing guidelines encourage the use of oropharyngeal swabs as an additional sample type for mpox diagnosis and suggest investigating the value of other specimens like blood samples.

Objective: In this study, we verified the value of select alternative specimen types for mpox laboratory confirmation.

Methods: We included 25 patients with MPXV-confirmed skin lesions to compare diagnostic sensitivity of MPXV PCR testing on EDTA plasma and two upper respiratory specimens: oropharyngeal swabs and saliva.

Results: In our patient cohort with MPXV-confirmed skin lesions, diagnostic sensitivity of MPXV PCR was 80% in EDTA plasma, 64% in oropharyngeal swabs, and 88% in saliva. MPXV viral loads were significantly higher in saliva compared to oropharyngeal swabs and EDTA plasma.

Discussion: The WHO recommendation to collect oropharyngeal swabs as an additional specimen for mpox diagnosis might need to be revised to include saliva wherever feasible. We suggest investigating saliva as a diagnostic specimen in the absence of active skin lesions or during the phase preceding skin manifestations. Moreover, the relatively high MPXV DNA content of saliva warrants elucidating its potential role in disease transmission.

Keywords: Blood; Diagnosis; Laboratory; Monkeypox; PCR; Saliva; Sensitivity; Specimens; Throat swab; plasma.

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Conflict of interest statement

Declaration of Competing Interest None

Figures

Fig 1
Fig. 1
Comparison of MPXV PCR Ct values generated on different indicated sample types from mpox patients testing positive on all three sample types (n = 14 out of 25 included mpox patients. All P-values denote two-way ANOVA with Tukey's multiple comparisons (the overall ANOVA P value is < 0.0001).
See this image and copyright information in PMC

References

    1. Perez Duque M., Ribeiro S., Martins J.V., Casaca P., Leite P.P., Tavares M., et al. Ongoing monkeypox virus outbreak, Portugal, 29 April to 23 May 2022. Euro Surveill. 2022;27(22) - PMC - PubMed
    1. Inigo Martinez J., Gil Montalban E., Jimenez Bueno S., Martin Martinez F., Nieto Julia A., Sanchez Diaz J., et al. Monkeypox outbreak predominantly affecting men who have sex with men, Madrid, Spain, 26 April to 16 June 2022. Euro Surveill. 2022;27(27) - PMC - PubMed
    1. Girometti N., Byrne R., Bracchi M., Heskin J., McOwan A., Tittle V., et al. Demographic and clinical characteristics of confirmed human monkeypox virus cases in individuals attending a sexual health centre in London, UK: an observational analysis. Lancet Infect. Dis. 2022 - PMC - PubMed
    1. Pan D., Sze S., Nazareth J., Martin C.A., Al-Oraibi A., Baggaley R.F., et al. Monkeypox in the UK: arguments for a broader case definition. Lancet. 2022;399(10344):2345–2346. - PMC - PubMed
    1. De Baetselier I., Van Dijck C., Kenyon C., Coppens J., Michiels J., de Block T., et al. Retrospective detection of asymptomatic monkeypox virus infections among male sexual health clinic attendees in Belgium. Nat. Med. 2022 - PMC - PubMed

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