Table 3.

Presence of SARS-CoV-2 RNA fragments (viral genomes) in the wastewater and sludge samples.

Source	No. of samples	Quantity of samples (mL)	Molecular detection methods	Concentration of vRNA	Area	SARS-CoV-2 concentration (gc/100 ml)	Covid-19 positive cases	Covid-19 cases	Sampling dates	References
WWTPs	13	200	RT-qPCR	–	Murcia		6 (46%)	662	12 March to April 14, 2020	Randazzo et al. (2020a, 2020b)
	10				Cartagena		6 (60%)	190
	13				Molina de		7 (54%)	70
					Segura
	13				Lorca		7 (54%)	31
	13				Cieza		7 (54%)	49
	10				Totana		4 (40%)	14
WWTPs		11	RT-qPCR primers and PCR	5.104 genome units/L	France		100% positive	404		Wurtzer et al. (2020)
Suburban pumping station (PS) and two WWTPs		100–200	RT-qPCR and PCR	–	Southeast Queensland	12	22.2% positive	404	24 Feb to April 04, 2020	Ahmed et al. (2020)
WWTPs		100–200	quantitative culturing, RNA extraction and RT-PCR	–	Netherlands	N1: 14/24	58% positive detected	1413	05 Feb to March 16, 2020	Medema et al. (2020)
						N2: 0/24
						N3: 8/24
						E: 5/24
Wastewater samples		36–150	RT-PCR	–	Netherland		Positive detected			Venugopal et al. (2020)
Wastewater samples		250	RT-qPCR	vRNA detected	(Milan) Italian National Institute of Health (ISS)	NA	–	–	3 Feb 2020 to April 2, 2020	Lapolla et al. (2020)
Wastewater samples		250	RT-qPCR	–	(Rome) Italian National Institute of Health (ISS)	NA	Positive detected	–	3 Feb 2020 to April 2, 2020
Non-drinkable street-cleaning water		11	RT-qPCR	–	Paris		Positive detected	–	05 March to April 09, 2020
WWTPs		250–1000	RT-qPCR	vRNA detected	Israel	NA	Positive detected	–	10 March to April 21, 2020	(Or et al., 2020)
Untreated wastewater		NA	RT-qPCR	vRNA detected	Wuchang Fangcang Hospital China	0.05–1.87 × 104		1124	26 Feb to march 10, 2020	Zhang et al. (2020)
Sewage samples		NA	RT-qPCR	vRNA detected	Massachusetts, USA	N1: 103–2 × 104	71% positive detected		18 to March 25, 2020	Randazzo et al. (2020a, 2020b)
						N2: 3 × 103 –
						104
						N3: 103–104
Sewage sludge samples		2.5	RT-qPCR	vRNA detected	New Haven, Connecticut, USA	1.7 × 105–4.6 × 107	Positive detected	2711	19 March to May 01, 2020	Peccia et al. (2020)
WWTPs		500	RT-qPCR	vRNA detected	Bozeman, Montana, USA	N1: 102–104	100% positive detected		23 March to April 08, 2020	Nemudryi et al. (2020)
						N2: 102–3 × 104
Sludge and wastewater	50	250	RT-qPCR	vRNA detected	Ourense, Spain	NA			04 to April 21, 2020	Balboa et al. (2020)
Sludge samples from WWTPs	9	250	RT-qPCR		Istanbul, Turkey	102–105	Positive detected		21 to April 25, 2020	Kocamemi et al. (2020)