sentence: In the studies reviewed , crAssphage , AdV and PyV showed no seasonal changes in concentrations in untreated and treated wastewater , river and seawater samples ( Carducci and Verani , 2013 ; Farkas et al ., 2018a , Farkas et al ., 2018 ; Fumian et al ., 2013 ; Iaconelli et al ., 2017 ; Masclaux et al ., 2013 ; Qiu et al ., 2015 ; Rusi ñ ol et al ., 2015 ; Schmitz et al ., 2016 ) .