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Volume 32, Supplement –Summer 2026
SUPPLEMENT ISSUE
Other
Progress and Expansion of the National Wastewater Surveillance System, United States, 2020–2024
, Megan Bias1, Stacie Reckling, Kaniz Madhobi, Daniel Cornforth, Igor Volkov, Andrew L. Rainey, Benjamin Lorentz, Kaitlin R. Taibl, Lisa P. Oakley, Rachel West, Rory Welsh, Jeffrey W. Mercante, Niketta Womack, Nicole Fehrenbach, and Jonathan Yoder
Table 2
Characteristics of samples submitted to the National Wastewater Surveillance System, United States, 2023, 2024, and 2020–2024*
| Samples | 2023 | 2024 | 2020–2024 |
|---|---|---|---|
| Total no. samples tested† | 155,165 | 148,023 | 456,594 |
| Time from sample collection to testing, d, median (IQR) | 3 (1–4) | 2 (1–4) | 2 (1–4) |
| Time from sample collection to reporting to 1CDP, d, median (IQR) | 7 (5–14) | 7 (4–10) | 8 (5–22) |
| Time from sample testing to reporting to 1CDP, d, median (IQR) |
4 (2–9) |
4 (1–7) |
5 (2–17) |
| Sample collection method, no. (%)‡ | |||
| Grab | 20,170 (13) | 20,073 (14) | 58,553 (13) |
| Manual composite | 2,382 (2) | 926 (<1) | 6,106 (1) |
| Flow-weighted composite | 58,552 (38) | 57,404 (39) | 189,379 (41) |
| Time-weighted composite | 73,031 (47) | 68,635 (46) | 200,086 (44) |
| Passive |
1,030 (<1) |
984 (<1) |
2,462 (<1) |
| Sample type, no. (%) | |||
| Untreated wastewater | 116,347 (75) | 104,958 (71) | 353,935 (78) |
| Wastewater post–grit removal | 30,286 (20) | 34,702 (23) | 78,122 (17) |
| Primary effluent | 189 (<1) | 186 (<1) | 465 (<1) |
| Primary sludge |
8,343 (5) |
8,177 (6) |
24,072 (5) |
| Sample management, no. (%)§ | |||
| Local health department | 3,614 (2) | 2,745 (2) | 10,429 (2) |
| State health department | 102,602 (66) | 105,578 (71) | 331,293 (72) |
| Commercial contractor | 23,692 (15) | 13,413 (9) | 58,332 (13) |
| Academic partner program |
25,553 (16) |
26,287 (18) |
56,993 (12) |
| PCR type, no. (%) | |||
| qPCR | 51,768 (33) | 19,656 (13) | 145,494 (32) |
| dPCR | 103,114 (66) | 127,891 (86) | 310,011 (68) |
| Multiple PCR types used |
283 (<1) |
476 (<1) |
1,089 (<1) |
| Endogenous wastewater control, no. (%) | |||
| Pepper mild mottle virus | 98,542 (64) | 96,592 (65) | 277,996 (61) |
| CrAssphage | 9,436 (6) | 10,049 (7) | 30,962 (7) |
| Other | 268 (<1) | 201 (<1) | 670 (<1) |
| None |
46,919 (30) |
41,181 (28) |
146,966 (32) |
| Exogenous wastewater control, no. (%) | |||
| Bovine coronavirus | 88,511 (57) | 109,731 (74) | 270,720 (59) |
| Bovine respiratory syncytial virus | 29,865 (19) | 4,418 (3) | 58,258 (13) |
| Other | 23,011 (15) | 21,821 (15) | 82,648 (18) |
| None |
13,778 (9) |
12,053 (8) |
44,968 (10) |
| No. samples sequenced for SARS-CoV-2 | 45,824 | 40,748 | 114,394 |
*1CDP, One CDC Data Platform (https://www.cdc.gov/data-modernization/php/one-cdc-data-platform/index.html); dPCR, digital PCR (including droplet digital PCR); IQR, interquartile range; qPCR, quantitative PCR. †Samples were counted based on unique sample identifications; if a sample was tested for multiple targets, the sample was only counted once. ‡Sample collection methods were determined using the most recent collection-method record associated with each sample. Collection method information may be missing for some samples, and a small number of samples were associated with multiple collection methods. §Sample management counts were not mutually exclusive. Samples could be associated with >1 management category.
1These first authors contributed equally to this article.