Table 1.
The results of SARS-CoV-2, MgV, and RVA detection in surface water and wastewater samples.
| Sample ID | Sample type | Location/Countya | Sampling date | 7-day incidence/100 000 residents/Countyb | E (Cq or gc/L)c | N (N1/N2 Cq or gc/L)c | nsp14 real-time RT-PCR (Cq) | nsp14-conventional RT-PCR | MgV Cq (% recovery) | RVA (Cq) |
|---|---|---|---|---|---|---|---|---|---|---|
| PV40 | Wastewater-effluent | Zagreb/ZG | 12.12.2019. | N/A | neg | negd | neg | neg | 27.5 (2.4) | pos (30.5) |
| PV41 | Surface water-city lake | Zagreb/ZG | 07.01.2020. | N/A | neg | neg | neg | neg | 31.7 (0.13) | neg |
| PV42 | Surface water-city lake | Zagreb/ZG | 07.01.2020. | N/A | neg | neg | neg | neg | 33.9 (0.03) | neg |
| PV43 | Surface water-city lake | Zagreb/ZG | 07.01.2020. | N/A | neg | negd | neg | neg | 28.1 (1.59) | pos (36.4) |
| PV44 | Wastewater-effluent | Zagreb/ZG | 28.02.2020. | N/D | neg | neg | neg | neg | 28.7 (1.04) | pos (30.3) |
| PV45 | Surface water-nature park | Lonjsko polje/SM | 04.03.2020. | N/A | neg | negd | neg | neg | 29.1 (0.79) | neg |
| PV46 | Surface water-nature park | Lonjsko polje/SM | 04.03.2020. | N/A | neg | neg | neg | neg | 31.3 (0.17) | neg |
| PV47 | Surface water-nature park | Lonjsko polje/SM | 04.03.2020. | N/A | neg | neg | neg | neg | 32.8 (0.06) | neg |
| PV48 | Surface water-nature park | Kopački rit/OB | 17.03.2020. | N/D | neg | neg | neg | neg | 28.1 (1.59) | pos (33.9) |
| PV49 | Surface water-nature park | Kopački rit/OB | 17.03.2020. | N/D | neg | neg | neg | neg | 29.5 (0.60) | neg |
| PV50 | Surface water-nature park | Kopački rit/OB | 17.03.2020. | N/D | neg | negd | neg | neg | 30.2 (0.37) | neg |
| PV51 | Wastewater-effluent | Zagreb/ZG | 15.05.2020. | N/D | neg | neg | neg | neg | 28.3 (1.38) | pos (34.7) |
| PV52 | Wastewater-effluent | Zagreb/ZG | 06.07.2020. | N/D | neg | neg | neg | neg | 30.2 (0.37) | pos (36.4) |
| PV53 | Wastewater-influent | Zagreb/ZG | 22.10.2020. | 461.9 | pos (33.2) | pos (7.2x103/33.4)d | pos (36.8) | pos | 27.1 (3.18) | pos (26.7) |
| PV54 | Wastewater-effluent | Zagreb/ZG | 22.10.2020. | 461.9 | neg | pos (6x101/neg)d | neg | neg | 28.4 (1.29) | pos (30.5) |
| PV55 | Wastewater-influent | Vinkovci/VS | 24.11.2020. | 401 | pos (33.6) | pos (2.1x103/33.3) | pos (36.4) | pos | 30.3 (0.34) | pos (24.8) |
| PV56 | Wastewater-effluent | Vinkovci/VS | 24.11.2020. | 401 | neg | neg | neg | neg | 28.4 (1.29) | pos (29.4) |
| PV57 | Wastewater-influent | Zadar-Centar/ZD | 07.12.2020. | 558.4 | pos (34.1) | pos (5.4x103/35.8) | neg | pos | 30.0 (0.42) | pos (26.7) |
| PV58 | Wastewater-effluent | Zadar-Centar/ZD | 07.12.2020. | 558.4 | neg | pos (1.8x102/35.0) | neg | neg | 29.1 (0.79) | pos (28.4) |
| PV59 | Wastewater-influent | Zadar-Borik/ZD | 07.12.2020. | 558.4 | <LOD | pos (9x102/36.3) | pos (34.5) | neg | 27.6 (2.25) | pos (30.7) |
| PV60 | Wastewater-influent | Split-Stupe/SD | 14.12.2020. | 508.4 | pos (34.7) | pos (34.8/8.9x103) | pos (36.6) | neg | 29.5 (0.60) | pos (27.8) |
| PV61 | Wastewater-influent | Split-Katalinića Brig/SD | 14.12.2020. | 508.4 | neg | neg | neg | neg | neg | pos (34.2) |
| PV62 | Wastewater-influent | Koprivnica/KK | 16.12.2020. | 433.6 | neg | pos (3.4x102/35.6) | neg | neg | 30.8 (0.24) | pos (28.0) |
| PV63 | Wastewater-effluent | Koprivnica/KK | 16.12.2020. | 433.6 | neg | neg | neg | neg | 27.9 (1.82) | pos (32.5) |
| PV64 | Wastewater-influent | Karlovac/KA | 19.01.2021. | 76.2 | pos (34.0) | pos (1.7x103/33.7) | neg | pos | 29.3 (0.69) | pos (24.7) |
| PV65 | Wastewater-effluent | Karlovac/KA | 19.01.2021. | 76.2 | neg | neg | neg | neg | 26.8 (3.92) | pos (28.0) |
| PV66 | Wastewater-influent | Slavonski Brod/BP | 21.01.2021. | 89.2 | pos (8.4x102) | negd | neg | neg | neg | pos (24.5) |
| PV67 | Wastewater-effluent | Slavonski Brod/BP | 21.01.2021. | 89.2 | neg | neg | neg | neg | 27.4 (2.58) | pos (26.5) |
| PV68 | Wastewater-influent | Zagreb/ZG | 28.01.2021. | 65 | pos (4x102) | pos (neg/35.4) | neg | neg | 30.6 (0.28) | pos (26.4) |
| PV69 | Wastewater-effluent | Zagreb/ZG | 28.01.2021. | 65 | neg | neg | neg | neg | 33.2 (0.05) | pos (28.3) |
SARS-CoV-2 positive samples and corresponding Cq or gc/L values are presented in boldface. Negative samples are referring to “no Cq” detected during respective real-time RT-PCR or to the absence of specific band in the conventional RT-PCR.
N/A (Not Applicable since the first documented human case of COVID-19 in the City of Zagreb County and Sisak-Moslavina County was evidenced on 25th of February 2020 and 13th of March 2020, respectively).
N/D (No Data; available from mid-August 2020 (HZJZ, 2021b)).
ZG (City of Zagreb), SM (Sisak-Moslavina), OB (Osijek-Baranja), VS (Vukovar-Srijem), ZD (Zadar), SD (Split-Dalmatia), KK (Koprivnica-Križevci), KA (Karlovac), BP (Brod-Posavina).
Six days after the sampling date. Data were retrieved from the published weekly reports (HZJZ, 2021b) of the Croatian Institute of Public Health (available from mid-August 2020). These data are county based, and the number of residents connected to WWTPs does not necessarily correspond to the county population.
SARS-CoV-2 quantity in gc/L was provided for the assay which resulted with the highest quantity. Influent samples below LOQ (7.5, 9.4 and 6.4 × 102gc/L for E, N1 and N2 assay, respectively) should be considered as estimated counts. Effluent samples below LOQ (2.6, 3.3 and 2.2 × 102gc/L for E, N1 and N2 assay, respectively) should be considered as estimated counts.
Human RNAse P positive.