“…Ixodes species tick populations have been increasing in the endemic regions and beyond and these vectors can transmit both B. burgdorferi and B. microti (Piesman et al, 1986; Jaenson et al, 2012; Lommano et al, 2012; Rizzoli et al, 2014; Johnson et al, 2017, 2018; Hahn et al, 2018; Piedmonte et al, 2018). The rise in incidence of B. microti and B. burgdorferi co-infections in humans appears to be driven primarily by increased co-infection of their common vector, ticks of the Ixodes species, which are capable of transmitting both pathogens simultaneously (Schulze et al, 2013; Dunn et al, 2014; Hersh et al, 2014; Knapp and Rice, 2015; Diuk-Wasser et al, 2016; Moutailler et al, 2016; Edwards et al, 2019). Although overall tick-borne co-infection rates are not yet documented in the United States, incidence of Lyme spirochetes and B. microti co-infections were as high as 40% in studies conducted with patient samples in two states in the Eastern United States, New Jersey and Connecticut (Diuk-Wasser et al, 2016; Primus et al, 2018).…”