Table 6.

Presence of viruses in aerosols at wastewater treatment plants.

Virus	Detection method	Plant descriptionc	Country	Wastewater levelsd	Aerosol levels	Remark	Reference
Coliphages	Plaque assaya	Aeration basin - lagoons	USA	3.25 × 103 to 5.53 × 105 PFU/L	<1 to 9 PFU/m3		(Brenner et al., 1988)
Coliphages	Plaque assay-MPNb	Two-stage aeration basins	USA	Not reported	5.0 × 10−3 to 7.6 × 10−2 MPN PFU/m3		(Fannin et al., 1985)
Somatic coliphages	Plaque assay	7 WWTPs	Finland	Not reported	Up to 380 PFU/m3		(Heinonen-Tanski et al., 2009)
F-specific coliphages	Plaque assay	7 WWTPs	Finland	Not reported	Up to 70 PFU/m3		(Heinonen-Tanski et al., 2009)
Adenoviruses	qPCR	79 WWTPs	Switzerland	Not reported	Up to 2.27 × 106 copies/m3	104/123 (84%) air samples positive	(Masclaux et al., 2014)
Adenoviruses, norovirus GI and GII, FRNA bacteriophages GIII, enteroviruses	qPCR	1 WWTP activated sludge chamber, exhaust duct, and treated air	Japan	Up to 2.5 × 107 copies/L (norovirus GII)	Up to 3.2 × 103 copies/m3	Air samples positive for adenovirus (4/16), norovirus GI (6/16), FRNA bacteriophages GIII (3/16), and enteroviruses (3/16)	(Matsubara and Katayama, 2019)

^aThree different E. coli strains (ATCC 13706, 15,597, and 11,303) were used as hosts.

^bMPN, most probable number.

^cWWTP, wastewater treatment plant.

^dPFU, plaque-forming unit.