Dados do Trabalho

Título

Detecting Human Adenovirus in Wastewater Samples from environmental underscore the Propagation of its A and F Species during the COVID-19 Pandemic in São Paulo

Introdução

Given the potential for a resurgence of Human adenoviruses (HAdVs) outbreaks after a global lockdown in the COVID-19 pandemic, their detection in wastewater is a crucial tool for their surveilling within the susceptible populations. Our study aimed to perform an affordable and sensitive molecular protocol for detecting and identifying species of HAdVs from environmental wastewater samples obtained previously through a project supported by GABRIEL Network (Global Approach to Biological Research, Infectious Diseases and Epidemics in Low-income countries).                                                                                                                                  

Objetivo (s)

(i) Evaluate the performance of an in-house real-time PCR test for HAdVs detection in sewage samples during the COVID-19 pandemic period; (ii) genotype species of HAdVs in this material by using a simplified sequencing protocol.

Material e Métodos

A convenience sampling of eighteen sewage collections were obtained from different sites of wastewater in São Paulo, Brazil: Hospital collection from HCFMUSP (Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo) and other sites in the same city in the period from February to July, 2022. A test was performed to detect the hexon gene of HAdVs and it was compared with a reference test by using twelve synthetic controls. Sanger sequencing of partial hexon gene target (~135 nucleotides) was carried out from 20 ng of PCR product. Phylogenetic analysis was performed using 34 prototypes from GenBank. There is no requirement for ethical approval for these samples or data.

Resultados e Conclusão

The in-house test was sensitive and its detection limit was of 15 copies per reaction. Its concordance with the reference test was 100%. The efficiency was of 98.64% (slope: -3.355; Y-intercept: 39.37; R²: 0.998). A positivity rate in sewage was of 77.8% (14/18). Six HAdV isolates with optimal viral load for DNA sequencing (> 2.8 log10 copies per reaction) was classified phylogenetically as belonging to the A and F species (mixed types 40/41). The molecular protocol was sensitive for identification of HAdVs isolates from environmental samples and underscore in the presence of F species 40/41 and A species of HAdV and the potential risk of impact on the local susceptible populations during the COVID-19 pandemic.

Palavras Chave

Human adenovirus; Real-Time PCR; Sequencing; Sewage.