Published 2023 | Version v1
Publication

Wastewater surveillance of SARS-CoV-2 variants in October–November 2022 in Italy: detection of XBB.1, BA.2.75 and rapid spread of the BQ.1 lineage

La Rosa G.
Brandtner D.
Bonanno Ferraro G.
Veneri C.
Mancini P.
Iaconelli M.
Lucentini L.
Del Giudice C.
Orlandi L.
Suffredini E.
Torlontano P.
Aprea G.
Scattolini S.
Acciari V. A.
La Bianca M.
Cifarelli R. A.
Palma A.
Lauria G.
La Vecchia G.
Malacaria E.
Folino G.
Calabria A.
Bulotta G.
D'Argenzio A.
Cossentino L.
Fusco G.
Viscardi M.
Tosco A.
Porta A.
Voli A.
Pennino F.
Lombardi A.
Angelini P.
Nasci D.
Alborali G.
Formenti N.
Guarneri F.
Fontani N.
Palumbo F.
Gentili L.
Mariuz M.
Trani G.
Pariani A.
De Lellis L.
Ancona C.
Barca A.
Serio F.
Giorgi D. A.
Ferrante I.
Monfrinotti M.
Scicluna M. T.
Cersini A.
Pietrella G.
Ottaviano C.
Arizzi M.
Nicosia E.
Grasselli E.
Izzotti A.
Tomesani I.
Bellisomi M.
Rosatto S.
Ammoni E.
Cereda D.
Bertasi B.
Oliva D.
Castiglioni S.
Schiarea S.
Binda S.
Primache V.
Pellegrinelli L.
Cocuzza C.
Franzetti A.
Bolognini L.
Filippetti F.
Paniccia' M.
Briscolini S.
Magi S.
Grucci A.
Colitti M.
Ciccaglione A.
Montanaro C.
Griglio B.
Costa A.
Decastelli L.
Bianchi A. R. M.
Carraro E.
Pignata C.
Richiardi L.
Bonetta S.
Albano N.
Di Vittorio G.
Mongelli O.
Apollonio F.
Triggiano F.
De Giglio O.
Montagna M. T.
Palermo M.
Maida C. M.
Mazzucco W.
Tramuto F.
De Grazia S.
Giammanco G.
Filizzolo C.
Purpari G.
Gucciardi F.
Ferrante M.
Agodi A.
Barchitta M.
Cala' P.
Carducci A.
Verani M.
Federigi I.
Ramazzotti M.
Rossolini G. M.
Santoro G.
Federici E.
Petricciuolo M.
Carnevali A.
Ruffier M.
Masieri L.
Grange E.
Damasco F.
Russo F.
Pitter G.
Groppi V.
Rigoli F.
Zampini M.
Baldovin T.
Amoruso I.
Cadonna M.
Postinghel M.
Foladori P.
Cutrupi F.
Zago L.
Stenico A.
Lea D.
Anna-Maria P.
Others:
La Rosa, G.
Brandtner, D.
Bonanno Ferraro, G.
Veneri, C.
Mancini, P.
Iaconelli, M.
Lucentini, L.
Del Giudice, C.
Orlandi, L.
Suffredini, E.
Torlontano, P.
Aprea, G.
Scattolini, S.
Acciari, V. A.
La Bianca, M.
Cifarelli, R. A.
Palma, A.
Lauria, G.
La Vecchia, G.
Malacaria, E.
Folino, G.
Calabria, A.
Bulotta, G.
D'Argenzio, A.
Cossentino, L.
Fusco, G.
Viscardi, M.
Tosco, A.
Porta, A.
Voli, A.
Pennino, F.
Lombardi, A.
Angelini, P.
Nasci, D.
Alborali, G.
Formenti, N.
Guarneri, F.
Fontani, N.
Palumbo, F.
Gentili, L.
Mariuz, M.
Trani, G.
Pariani, A.
De Lellis, L.
Ancona, C.
Barca, A.
Serio, F.
Giorgi, D. A.
Ferrante, I.
Monfrinotti, M.
Scicluna, M. T.
Cersini, A.
Pietrella, G.
Ottaviano, C.
Arizzi, M.
Nicosia, E.
Grasselli, E.
Izzotti, A.
Tomesani, I.
Bellisomi, M.
Rosatto, S.
Ammoni, E.
Cereda, D.
Bertasi, B.
Oliva, D.
Castiglioni, S.
Schiarea, S.
Binda, S.
Primache, V.
Pellegrinelli, L.
Cocuzza, C.
Franzetti, A.
Bolognini, L.
Filippetti, F.
Paniccia', M.
Briscolini, S.
Magi, S.
Grucci, A.
Colitti, M.
Ciccaglione, A.
Montanaro, C.
Griglio, B.
Costa, A.
Decastelli, L.
Bianchi, A. R. M.
Carraro, E.
Pignata, C.
Richiardi, L.
Bonetta, S.
Albano, N.
Di Vittorio, G.
Mongelli, O.
Apollonio, F.
Triggiano, F.
De Giglio, O.
Montagna, M. T.
Palermo, M.
Maida, C. M.
Mazzucco, W.
Tramuto, F.
De Grazia, S.
Giammanco, G.
Filizzolo, C.
Purpari, G.
Gucciardi, F.
Ferrante, M.
Agodi, A.
Barchitta, M.
Cala', P.
Carducci, A.
Verani, M.
Federigi, I.
Ramazzotti, M.
Rossolini, G. M.
Santoro, G.
Federici, E.
Petricciuolo, M.
Carnevali, A.
Ruffier, M.
Masieri, L.
Grange, E.
Damasco, F.
Russo, F.
Pitter, G.
Groppi, V.
Rigoli, F.
Zampini, M.
Baldovin, T.
Amoruso, I.
Cadonna, M.
Postinghel, M.
Foladori, P.
Cutrupi, F.
Zago, L.
Stenico, A.
Lea, D.
Anna-Maria, P.

Description

This study adds insight regarding the occurrence and spread of SARS-CoV-2 Variants of Concern (VOCs) and Variants of Interest (VOIs) in Italy in October and November 2022, by testing urban wastewater collected throughout the country. A total of 332 wastewater samples were collected from 20 Italian Regions/Autonomous Provinces (APs) within the framework of national SARS-CoV-2 environmental surveillance. Of these, 164 were collected in the first week of October and 168 in the first week of November. A ∼1600 bp fragment of the spike protein was sequenced by Sanger (for individual samples) and long-read nanopore sequencing (for pooled Region/AP samples). In October, mutations characteristic of Omicron BA.4/BA.5 were detected in the vast majority (91 %) of the samples amplified by Sanger sequencing. A fraction of these sequences (9 %) also displayed the R346T mutation. Despite the low prevalence documented in clinical cases at the time of sampling, amino acid substitutions characteristic of sublineages BQ.1 or BQ.1.1 were detected in 5 % of sequenced samples from four Regions/APs. A significantly higher variability of sequences and variants was documented in November 2022, when the rate of sequences harbouring mutations of lineages BQ.1 and BQ1.1 increased to 43 %, and the number of Regions/APs positive for the new Omicron subvariant more than tripled (n = 13) compared to October. Moreover, an increase in the number of sequences with the mutation package BA.4/BA.5 + R346T (18 %), as well as the detection of variants never observed before in wastewater in Italy, such as BA.2.75 and XBB.1 (the latter in a Region where no clinical cases associated with this variant had ever been documented) was recorded. The results suggest that, as predicted by the ECDC, BQ.1/BQ.1.1 is rapidly becoming dominant in late 2022. Environmental surveillance proves to be a powerful tool for tracking the spread of SARS-CoV-2 variants/subvariants in the population.

Additional details

Created:
February 14, 2024
Modified:
February 14, 2024