The data published here are based on information obtained from the federal government's national wastewater monitoring system. Since January 2022, the national wastewater monitoring system of Switzerland and the Principality of Liechtenstein has determined the SARS-CoV-2 viral load in the wastewater of participating wastewater treatment plants (WWTP) at regular intervals.
Wastewater samples are collected from wastewater treatment plants three to six times per week. The absolute viral load (gene copies/day) is specified per 100,000 inhabitants. A dilution factor based on the wastewater treatment plant's flow volume is taken into account, for instance during dry periods. The relative viral load is the measured viral load (gene copies/day) as a proportion of the historically measured maximum value. The proportion of relative viral load is calculated by dividing the proportion of absolute viral load by the proportion of the historic maximum viral load value. The residential population comprises the catchment area of each wastewater treatment plant (WWTP). Seasonal fluctuations in the non-permanent population, which influence the viral load particularly in busy tourist areas, are not included. Wastewater treatment plants (WWTP) no longer participating in the project will not be included when calculating the proportion of viral load per category. However, historical measurements will still be available when viewing the development over time.
Detailed information on the measuring methods and terminology can be found on the Eawag website. New findings may prompt adjustments to data calculations.
The timeframe desired can be selected using the slider below the chart.
Geographical distribution
Viral load in wastewater, Vaud, 07.02.2022 to 30.01.2023
The graph shows the relative viral load in per cent as a 7-day average in the wastewater treatment plants (WWTPs) and the difference in viral load compared with the previous week in percentage points (pp) in Switzerland and Liechtenstein. The percentage point figure is used to compare percentages. The 7-day relative share refers to the historical maximum values for each wastewater treatment plant.
Cant.
Name
Population coverage
Relative viral load
Difference to previous week
AG
Aarau
AG Aarau
78 255
32,2%
24,9
AG
Aarburg
AG Aarburg
30 884
63,3%
58,3
AG
Baden
AG Baden
59 560
16,3%
13,3
AG
Bremgarten
AG Bremgarten
22 613
19,1%
15,4
AG
Brugg
AG Brugg
46 250
41,3%
39,4
AG
Kaisten
AG Kaisten
25 354
0,9%
-
AG
Lenzburg
AG Lenzburg
54 568
47,1%
-
AG
Reinach
AG Reinach
23 817
1,0%
-
AG
Wohlen
AG Wohlen
31 992
22,6%
19,5
AG
Zofingen
AG Zofingen
35 577
3,5%
−8,7
AI
Appenzell (Boedeli)
AI Appenzell (Boedeli)
11 877
8,5%
3,0
AR
Herisau (Bachwis)
AR Herisau (Bachwis)
16 500
10,5%
−6,5
BE
Aarwangen (Zala)
BE Aarwangen (Zala)
40 845
12,4%
0,7
BE
Biel
BE Biel
85 389
17,9%
−4,3
BE
Grindelwald
BE Grindelwald
4153
2,1%
−5,7
BE
Interlaken
BE Interlaken
27 945
11,3%
−9,9
BE
Laupen
BE Laupen
62 000
4,4%
0,3
BE
Lauterbrunnen
BE Lauterbrunnen
2553
14,6%
-
BE
Lyss
BE Lyss
36 358
15,4%
4,5
BE
Mittl. Emmental
BE Mittl. Emmental
25 733
5,2%
1,1
BE
Moossee-Urtenenbach
BE Moossee-Urtenenbach
33 844
12,3%
3,9
BE
Region Bern
BE Region Bern
224 557
1,2%
−4,5
BE
Saanen
BE Saanen
9253
40,6%
30,3
BE
Thunersee
BE Thunersee
124 550
2,0%
0,9
BE
Worblental
BE Worblental
71 636
9,0%
−10,4
BS
Basel
BS Basel
273 075
12,6%
8,5
FL
Liechtenstein
FL Liechtenstein
39 315
2,1%
−6,1
FR
Fribourg (Aele)
FR Fribourg (Aele)
44 211
2,7%
−0,3
FR
Vuippens (Ais)
FR Vuippens (Ais)
34 647
11,2%
−19,4
GE
Aire
GE Aire
451 771
7,3%
−0,7
GE
Satigny/Bois-de-Bay
GE Satigny/Bois-de-Bay
79 577
19,5%
7,6
GE
Thonex/Villette
GE Thonex/Villette
51 028
9,2%
5,2
GL
Glarnerland
GL Glarnerland
49 644
14,7%
3,0
GR
Arosa
GR Arosa
2049
16,0%
−6,7
GR
Cazis (Waldau)
GR Cazis (Waldau)
10 963
9,0%
−6,3
GR
Chur
GR Chur
55 000
7,8%
−1,5
GR
Davos (Gadenstatt)
GR Davos (Gadenstatt)
9706
6,2%
−5,3
GR
Klosters (Gulfia)
GR Klosters (Gulfia)
3155
66,2%
−22,0
GR
Landquart
GR Landquart
17 054
46,6%
21,8
GR
Poschiavo (Li Geri)
GR Poschiavo (Li Geri)
3358
80,3%
70,2
GR
S-chanf (Oberengadin)
GR S-chanf (Oberengadin)
15 056
23,1%
1,5
GR
Schluein (Gruob)
GR Schluein (Gruob)
7823
21,6%
9,3
GR
Scuol (Sot Ruinas)
GR Scuol (Sot Ruinas)
3473
45,6%
23,1
GR
Seewis (Vorderes Prättigau)
GR Seewis (Vorderes Prättigau)
8003
17,1%
10,9
JU
Delemont (Sede)
JU Delemont (Sede)
36 484
1,5%
−1,3
JU
Porrentruy (Sepe)
JU Porrentruy (Sepe)
16 500
2,3%
−1,7
LU
Buholz (Real)
LU Buholz (Real)
183 511
6,2%
−3,6
LU
Rontal
LU Rontal
28 771
32,2%
−44,6
NE
Colombier (La Saunerie)
NE Colombier (La Saunerie)
27 582
5,4%
−31,3
NE
La-Chaux-de-Fonds
NE La-Chaux-de-Fonds
35 360
0,4%
−16,0
NE
Neuchatel
NE Neuchatel
40 697
3,3%
0,1
NW
Stans (Rotzwinkel)
NW Stans (Rotzwinkel)
21 214
8,0%
−4,7
OW
Alpnach (Sarneraatal)
OW Alpnach (Sarneraatal)
30 657
29,0%
6,9
OW
Engelberg
OW Engelberg
4053
18,1%
−3,2
SG
Altenrhein
SG Altenrhein
64 000
8,1%
0,0
SG
Au (Rosenbergsau)
SG Au (Rosenbergsau)
41 281
5,9%
−5,0
SG
Bad Ragaz
SG Bad Ragaz
12 007
6,8%
−1,6
SG
Buchs
SG Buchs
24 844
2,7%
−5,2
SG
Flawil (Oberglatt)
SG Flawil (Oberglatt)
30 378
6,6%
−9,8
SG
Flums (Seez)
SG Flums (Seez)
12 448
0,7%
−0,5
SG
Rapperswil-Jona
SG Rapperswil-Jona
28 168
1,2%
−1,4
SG
St.Gallen (Au)
SG St.Gallen (Au)
37 876
4,0%
−1,9
SG
St.Gallen (Hofen)
SG St.Gallen (Hofen)
57 031
13,8%
6,2
SG
Steinach (Morgental)
SG Steinach (Morgental)
30 710
5,4%
−1,3
SG
Wil
SG Wil
26 295
4,9%
−1,5
SH
Hallau (Klettgau)
SH Hallau (Klettgau)
14 795
6,6%
−2,1
SH
Neuhausen A/Rhf. (Roeti)
SH Neuhausen A/Rhf. (Roeti)
56 967
10,0%
8,0
SH
Ramsen (Bibertal-Hegau)
SH Ramsen (Bibertal-Hegau)
100 338
6,4%
−4,2
SO
Grenchen (Buerenamt)
SO Grenchen (Buerenamt)
46 563
8,5%
−8,2
SO
Winznau (Zv Olten)
SO Winznau (Zv Olten)
54 540
8,1%
−6,7
SO
Zuchwil (Soloth.-Emme)
SO Zuchwil (Soloth.-Emme)
95 793
3,7%
0,4
SZ
Hoefe
SZ Hoefe
29 624
35,4%
4,6
SZ
Schwyz
SZ Schwyz
31 164
8,4%
−3,4
SZ
Untermarch
SZ Untermarch
29 470
18,7%
−0,3
TG
Frauenfeld
TG Frauenfeld
36 369
3,9%
0,7
TG
Hefenhofen (Aachtal, Moos)
TG Hefenhofen (Aachtal, Moos)
23 074
4,9%
−0,1
TG
Weinfelden (Mittelthurgau)
TG Weinfelden (Mittelthurgau)
31 342
22,8%
11,2
TI
Bellinzona (Giubiasco)
TI Bellinzona (Giubiasco)
53 209
55,2%
16,8
TI
Chiasso (Vacallo)
TI Chiasso (Vacallo)
26 638
19,6%
11,3
TI
Locarno (Foce Maggia)
TI Locarno (Foce Maggia)
50 781
15,3%
4,9
TI
Locarno (Foce Ticino)
TI Locarno (Foce Ticino)
24 516
56,4%
−21,6
TI
Lugano
TI Lugano
124 000
12,8%
0,5
TI
Mendrisio (Rancate)
TI Mendrisio (Rancate)
29 392
79,3%
34,2
UR
Altdorf
UR Altdorf
33 940
8,3%
−0,2
VD
Commugny
VD Commugny
22 575
38,2%
−12,8
VD
Gland (Apec)
VD Gland (Apec)
36 034
44,7%
3,3
VD
Lausanne (Vidy)
VD Lausanne (Vidy)
247 824
3,3%
−4,5
VD
Montreux/Pierrier
VD Montreux/Pierrier
41 383
31,8%
−13,2
VD
Morges
VD Morges
39 126
29,7%
11,8
VD
Nyon
VD Nyon
25 753
17,3%
-
VD
Vevey (Aviron)
VD Vevey (Aviron)
53 864
32,2%
−2,2
VD
Yverdon
VD Yverdon
35 462
43,1%
−11,1
VS
Bagnes-Le Châble
VS Bagnes-Le Châble
7713
9,4%
−5,3
VS
Brig-Glis (Briglina)
VS Brig-Glis (Briglina)
28 678
3,5%
−0,4
VS
Goms
VS Goms
4193
15,3%
−7,8
VS
Martigny
VS Martigny
39 643
0,8%
−0,8
VS
Sierre/Noes
VS Sierre/Noes
32 480
5,2%
−1,9
VS
Sion/Chateauneuf
VS Sion/Chateauneuf
35 632
10,3%
−7,6
VS
Zermatt
VS Zermatt
5507
33,3%
−18,5
ZG
Cham (Schoenau)
ZG Cham (Schoenau)
146 942
2,4%
−9,7
ZH
Affoltern am Albis
ZH Affoltern am Albis
30 226
25,3%
−4,4
ZH
Andelfingen
ZH Andelfingen
7150
31,7%
−13,5
ZH
Bülach
ZH Bülach
35 612
13,3%
7,3
ZH
Dietikon (Limeco)
ZH Dietikon (Limeco)
83 367
16,0%
2,8
ZH
Dübendorf (Ika Neugut)
ZH Dübendorf (Ika Neugut)
39 622
89,4%
−6,4
ZH
Horgen
ZH Horgen
26 952
76,8%
16,4
ZH
Illnau-Effretikon
ZH Illnau-Effretikon
18 921
18,2%
−12,7
ZH
Meilen (Rorguet)
ZH Meilen (Rorguet)
26 447
44,9%
1,3
ZH
Niederglatt (Fischb.-Gl.)
ZH Niederglatt (Fischb.-Gl.)
43 596
25,6%
−2,7
ZH
Uster (Jungholz)
ZH Uster (Jungholz)
41 303
37,7%
−8,7
ZH
Werdhölzli
ZH Werdhölzli
471 000
9,2%
1,1
ZH
Wetzikon (Flos)
ZH Wetzikon (Flos)
31 419
58,2%
18,4
ZH
Winterthur
ZH Winterthur
140 403
30,4%
14,6
Geographic distribution over time
View the development of the virus load in wastewater at various WWTPs in Switzerland and Liechtenstein.
The figure shows the 7-day average absolute and relative viral load in percent in the wastewater treatment plants (WWTP) and the difference from the previous week's 7-day average in percentage points (pp) in Switzerland and Liechtenstein. The relative proportion per 7-day period refers to the historically measured maximum value per wastewater treatment plant.
Data only available for individual WWTP Search by WWTP