Please see below for the latest update on Merced, Stanislaus, and Yolo County wastewater data.

  • Weeks 79-80: 04/23 - 05/06
  • Weeks 81-82: 05/07 - 05/20

Table 1: Variant to N-Gene Proportions (Week 82)

Last Week’s Variant to N-Gene Proportions
Site XBB HV 69 70
Davis 55% (46-64) 0% (0- 0)
Esparto 87% (87-87) 0% (0- 0)
Los Banos 71% (54-95) 4% (0-11)
Merced 79% (59-98) 2% (0- 4)
Modesto 30% ( 0-60) 0% (0- 0)
Turlock 76% (57-93) 0% (0- 0)
Winters 25% ( 0-50) 0% (0- 0)
Woodland 69% (65-72) 0% (0- 0)
* Average (min-max)

General Update

Table 2: Percentage of change

Percent change
Virus Merced County Stanislaus County Yolo County
Merced Los Banos Modesto Turlock Davis Esparto Winters Woodland
SARS-CoV-2 23% +42% 35% +10% 50% 89% 6% +LL
Influenza A ND ND ND ND ND ND ND ND
Influenza B ND ND ND ND ND +35% ND ND
RSV ND ND ND +LL +185% ND ND ND
HMPV 70% +3% ND 44% 76% ND +LL 65%
Norovirus 41% +42% 27% +29% 57% +84% 16% +4%
Weeks: 79-80: 04/23 - 05/06
Weeks: 81-82: 05/07 - 05/20
Percent change is calculated here using average of measurements over the past two weeks compared to the average of measurements from the prior two weeks.
ND- Non-detect (below detection limit)
+LL increasing but at low levels

Table 3: Current wastewater level

Current wastewater level
Virus Merced County Stanislaus County Yolo County
Merced Los Banos Modesto Turlock Davis Esparto Winters Woodland
SARS-CoV-2 Low Low Low Low Low Low Low Low
Influenza A Low Low Low Low Low Low Low Low
Influenza B Low Low Low Low Low High Low Low
RSV Low Low Low Medium Low Low Low Low
HMPV Low Low Low Low Medium Low Low Low
Norovirus Low High High High Low High Low High
The current wastewater levels are estimated using the 10-day rolling average (10-dma). The 33rd and 66th percentiles are calculated over the past 365 days before 14 days ago. For cities with less than 365 days, all days before 14 days ago are used. The current wastewater level is classified as:
• Low: The current 10-dma is below 33rd percentile
• Medium: The current 10-dma is between the 33rd and 66th percentile
• High: The current 10-dma is above 66th Percentile

Trend test for SARS-CoV-2

Table 4: Relative Strength Index

The Relative Strength Index
Virus Merced County Stanislaus County Yolo County
Merced Los Banos Modesto Turlock Davis Esparto Winters Woodland
SARS-CoV-2 No Trend No Trend No Trend No Trend No Trend No Trend No Trend No Trend
Influenza A No Data No Data No Data Downward Downward No Data No Trend No Data
Influenza B No Trend No Data No Data No Data No Data Likely upward No Data Very likely downward
RSV No Trend No Data No Data Very likely upward No Trend No Data No Data No Data
HMPV No Trend No Trend Downward No Trend No Trend Downward Likely upward No Trend
Norovirus Likely downward No Trend No Trend No Trend No Trend Likely upward No Trend No Trend
Week 82: 04/30 - 05/06
* The Relative Strength Index (RSI) calculates a ratio of the recent upward price movements to the absolute price movement. Developed by J. Welles Wilder.

Table 5: Percent change (PC)

Percent change in the last 14 days
Virus Merced County Stanislaus County Yolo County
Merced Los Banos Modesto Turlock Davis Esparto Winters Woodland
SARS-CoV-2 No Trend No Trend Very likely downward Very likely downward Very likely downward Very likely downward Likely downward No Trend
Influenza A No Trend No Trend No Trend No Trend Downward No Trend Very likely downward No Trend
Influenza B Very likely downward No Trend No Trend No Trend No Trend Upward No Trend No Trend
RSV Downward No Trend No Trend Upward Likely upward No Trend No Trend No Trend
HMPV Very likely downward No Trend Very likely downward Very likely upward Very likely downward No Trend Very likely upward Likely downward
Norovirus Very likely downward No Trend Very likely downward Very likely upward Very likely downward Very likely upward Very likely downward Likely upward
Week 82: 04/30 - 05/06
* The slope is calculated from a least-squares linear regression of log10-transformed values of the N/PMMoV data versus day. We used a 14-day look-back period to calculate the slope. For each slope estimate, we extracted the 90%, 95%, and 99% confidence intervals (CIs) to calculate the 90%, 95%, and 99% CIs for each PC estimate. We interpreted PC values greater than 0 for the 90%, 95%, and 99% upper CIs as upward, likely upward, and very likely upward trends, respectively. We interpreted PC values less than 0 for the 90%, 95%, and 99% lower CIs as downward, likely downward, and very likely downward trends day and previous n - 1 days.

Table 6: Mann-Kendall trend test

Mann-Kendall trend test
Virus Merced County Stanislaus County Yolo County
Merced Los Banos Modesto Turlock Davis Esparto Winters Woodland
SARS-CoV-2 No Trend No Trend Very likely downward Likely downward Very likely downward Very likely downward Likely downward No Trend
Influenza A No Data No Data No Data No Trend Very likely downward No Data Very likely downward No Data
Influenza B Very likely downward No Data No Data No Data No Data No Trend No Data No Data
RSV Very likely downward No Data No Data Likely upward Very likely upward No Data No Data No Data
HMPV Very likely downward No Trend Very likely downward Likely upward Very likely downward No Trend Very likely upward Likely downward
Norovirus Likely downward No Trend Very likely downward Very likely upward Very likely downward Very likely upward Very likely downward Upward
Week 82: 04/30 - 05/06
* The Mann-Kendall (MK) trend test is a nonparametric test that evaluates whether there is a monotonic trend in a time-series dataset. We applied the MK trend test to raw N/PMMoV data and used a 14-day lookback period. We interpreted positive values of the test statistic, tau (τ), with p ≤ 0.1, p ≤ 0.05, and p ≤ 0.01 as upward, likely upward, and very likely upward trends, respectively. We interpreted negative τ values with p ≤ 0.1, p ≤ 0.05, and p ≤ 0.01 as downward, likely downward, and very likely downward trends, respectively.

Merced County

SARS-CoV-2

Merced’s average SARS-CoV-2 concentrations (N/PMMoV) decreased ⬇️ by 23% between the most recent two weeks and the two weeks prior to that. Los Banos’ average increased ⬆️ by 42%.

Fig 1. Merced

Fig 2. Los Banos

Influenza A

Merced’s average Influenza A concentrations (Flu A/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Los Banos’ average showed no detection.

Influenza B

Merced’s average Influenza B concentrations (Flu B/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Los Banos’ average showed no detection.

RSV

Merced’s average RSV concentrations (RSV/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Los Banos’ average showed no detection.

HMPV

Merced’s HMPV concentrations (HMPV/PMMoV) decreased ⬇️ by 70% between the most recent two weeks and the two weeks prior to that. Los Banos’s average remained the same 🔄.

Norovirus

Merced’s average Norovirus concentrations (Norovirus/PMMoV) decreased ⬇️ by 41% between the most recent two weeks and the two weeks prior to that. Los Banos’ average increased ⬆️ by 42%.

Fig. Merced

Fig. Los Banos

Stanislaus County

SARS-CoV-2

Modesto’s average SARS-CoV-2 concentrations (N/PMMoV) decreased ⬇️ by 35% between the most recent two weeks and the two weeks prior to that. Turlock’s average increased ⬆️ by 10%.

Fig 1. Modesto

Fig 2. Turlock

Influenza A

Modesto’s average Influenza A concentrations (Flu A/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Turlock’s average showed no detection.

Influenza B

Modesto’s average Influenza B concentrations (Flu B/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Turlock’s average showed no detection.

RSV

Modesto’s average RSV concentrations (RSV/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Turlock’s average increased ⬆️ by 100%.

HMPV

Modesto’s average HMPV concentrations (HMPV/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Turlock’s average decreased ⬇️ by 44%.

Norovirus

Modesto’s average Norovirus concentrations (Norovirus/PMMoV) decreased ⬇️ by 27% between the most recent two weeks and the two weeks prior to that. Turlock’s average increased ⬆️ by 29%.

Fig. Modesto

Fig. Turlock

Yolo County

SARS-CoV-2

Davis’ average SARS-CoV-2 concentrations (N/PMMoV) decreased ⬇️ by 50% between the most recent two weeks and the two weeks prior to that. Esparto’s average decreased ⬇️ by 89%. Winters’ average decreased ⬇️ by 6%. Woodland’s average increased ⬆️ by 100%.

Fig 1. Davis

Fig 2. Esparto

Fig 3. Winters

Fig 4. Woodland

Influenza A

Davis’ average Influenza A concentrations (Flu A/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Esparto’s average showed no detection. Winters’ average showed no detection. Woodland’s average showed no detection.

Influenza B

Davis’ average Influenza B concentrations (Flu B/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Esparto’s average increased ⬆️ by 35%. Winters’ average showed no detection. Woodland’s average showed no detection.

RSV

Davis’ average RSV concentrations (RSV/PMMoV) increased ⬆️ by 185% between the most recent two weeks and the two weeks prior to that. Esparto’s average showed no detection. Winters’ average showed no detection. Woodland’s average showed no detection.

HMPV

Davis’ HMPV concentrations (HMPV/PMMoV) decreased ⬇️ by 76% between the most recent two weeks and the two weeks prior to that. Esparto’s average showed no detection. Winters’ average increased ⬆️ by 100%. Woodland’s average decreased ⬇️ by 65%.

Norovirus

Davis’ Norovirus concentrations (Norovirus/PMMoV) decreased ⬇️ by 57% between the most recent two weeks and the two weeks prior to that. Esparto’s average increased ⬆️ by 84%. Winters’ average decreased ⬇️ by 16%. Woodland’s average remained the same 🔄.

Fig. Davis

Fig. Esparto

Fig. Winters

Fig. Woodland

All Counties

Mpox Update

There are no detections for samples taken at our plants from the last two weeks. https://healthycvtogether.org/monkeypox-data/

Influenza B

Davis’ average Influenza B concentrations (Flu B/PMMoV) showed no detection between the most recent two weeks and the two weeks prior to that. Esparto’s average increased ⬆️ by 35%. Winters’ average showed no detection. Woodland’s average showed no detection. Merced’s average showed no detection. Los Banos’ average showed no detection. Modesto’s average showed no detection. Turlock’s average showed no detection