Autor(es):
Cordeiro, Rita ; Pelerito, Ana ; de Carvalho, Isabel Lopes ; Lopo, Sílvia ; Neves, Raquel ; Rocha, Raquel ; Palminha, Paula ; Verdasca, Nuno ; Palhinhas, Cláudia ; Borrego, Maria José ; Manita, Carla ; Ferreira, Idalina ; Bettencourt, Célia ; Vieira, Patrícia ; Silva, Sónia ; Água-Doce, Ivone ; Roque, Carla ; Cordeiro, Dora ; Brondani, Greice ; Santos, João Almeida ; Martins, Susana ; Rodrigues, Irene ; Ribeiro, Carlos ; Núncio, Maria Sofia ; Gomes, João Paulo ; Batista, Fernando da Conceição
Data: 2024
Identificador Persistente: http://hdl.handle.net/10400.18/10442
Origem: Repositório Científico do Instituto Nacional de Saúde
Assunto(s): Ct Values; Monkeypox Virus; Clinical Samples; Positive Rate; Viral Clearance; Viral Load; Portugal; Infecções Sistémicas e Zoonoses
Descrição
Mpox is a zoonotic disease caused by the Monkeypox virus (MPXV), and since May 2022, tens of thousands of cases have been reported in non-endemic countries. We aimed to evaluate the suitability of different sample types for mpox diagnostic and assess the temporal dynamics of viral load. We evaluated 1914 samples from 953 laboratory-confirmed cases. The positivity rate was higher for lesion (91.3%) and rectal swabs (86.1%) when compared with oropharyngeal swabs (69.5%) and urines (41.2%), indicating higher viral loads for the former. Supporting this, lesion and rectal swabs showed lower median PCR C values (C = 23 and C = 24), compared to oropharyngeal swabs and urines (C = 31). Stable MPXV loads were observed in swabs from lesions up to 30 days after symptoms onset, contrasting with a considerable decrease in viral load in rectal and oropharyngeal swabs. Overall, these results point to lesion swabs as the most suitable samples for detecting MPXV in the 2022-2023 multicountry outbreak and show comparable accuracy to rectal swabs up to 8 days after symptoms onset. These findings, together with the observation that about 5% of patients were diagnosed through oropharyngeal swabs while having negative lesions, suggest that multisite testing should be performed to increase diagnostic sensitivity.
