Staying informed about respiratory virus trends is vital for protecting your health and the well-being of our community.

The Santa Cruz County Respiratory Dashboard provides up-to-date information on COVID-19, Influenza (flu) and RSV, including data on wastewater concentrations, hospitalizations, and associated deaths. This interactive resource helps residents track local trends, spot early warning signs of outbreaks, and understand the seasonal patterns of respiratory viruses. Wastewater surveillance offers a powerful tool to detect rising virus levels before clinical cases surge, while hospitalization and mortality data help guide timely responses by health officials and medical providers

Updated weekly and based on sources like the Center for Disease Control (CDC) and California Department of Public Health (CDPH), this dashboard empowers you to make informed decisions and stay ahead of potential health risks throughout the respiratory virus season.

Wastewater Data

Wastewater surveillance is a helpful tool for tracking diseases in a community because it allows public health experts to detect viruses and bacteria that people release in their waste — sometimes even before they feel sick or go to the doctor. When people use the bathroom, small traces of viruses or bacteria (like COVID-19, Influenza (flu), or norovirus) are flushed into the sewage system. By collecting and testing samples of this wastewater, scientists can look for signs of pathogens in the community.

This method is especially useful because it can give early warning signs of disease transmission in a community. Sometimes, the amount of viruses in the wastewater goes up before hospitals or clinics start seeing more sick people. That means health officials can spot rising levels of illness early and take steps to respond — like increasing testing, sharing public warnings, or preparing hospitals — before a full outbreak happens. It’s a fast, cost-effective way to monitor the health of large groups of people all at once, without needing everyone to get tested individually.

Current Status of COVID-19 in Santa Cruz County

Let’s keep working together to keep our community safe and healthy! Remember to wash your hands, wear a mask in crowded places, and stay home if you’re feeling sick.

How to read the plot: The plot shows green (for good) when Rt is below 1 and COVID-19 spread is decreasing. When Rt is above 1 and COVID-19 spread is increasing, the plot is yellow (take caution). The darker line shows the most likely Rt in Santa Cruz county. Since models are not perfect, the shaded areas around the darker line show the range of likely Rt values. Please note that case data from the last 7 days are frequently updated and are excluded from the estimation of Rt.

Rt: COVID-19 Spread in Our Community

The Effective Reproductive Number, shown here as “Rt” helps us understand how fast COVID-19 is spreading in our community. For COVID-19, Rt tells us the average number of people who will contract this disease from each infected person.

For example, if Rt equals 1, each existing infection causes one new infection. An Rt equal to 1 means the disease will stay present and stable in our community.

If Rt is less than 1, each existing infection causes less than one new infection. Therefore, if Rt stays below 1, spread of the disease declines and it eventually leaves the community.

When Rt is more than 1, each existing COVID-19 infection causes more than one new infection. The disease will be transmitted between more and more people and the spread of the disease is growing. If Rt stays greater than 1, it can lead to many challenges, including hospitals not being able to care for everyone who gets sick.

Rt depends on people’s behavior, like wearing a mask or keeping social distance. This is why Rt can change over time.

Santa Cruz County COVID-19 Hospitalization Projections

For current information on hospital usage including ICU beds, please visit the California COVID-19 Hospital data page.

How to read the model: For the actual number of hospitalizations in the past, we use the blue dots. To look at the future, we use the dark blue line and the light blue area. The dark blue line is the most likely number of hospitalizations in the future. Since models are not perfect, the light blue wider area shows the range of likely hospitalizations.”

Why We Forecast Hospitalizations

We all rely on our hospitals to take care of us when we are very ill. If a hospital gets too full, it doesn’t have enough space or staff to care for everyone.

So, it is important to keep track of how many people are staying in a hospital at one time. It is also important to use our forecasts to predict when hospitals might get too full.

When our hospitals start to get too full, we need to take actions to slow the spread of COVID-19.

Tracking and forecasting how many people are in our hospitals help us SAVE Lives in our community.

Santa Cruz County COVID-19 Wastewater Projections

How to Read This Model

In order to help calculate the risk of getting a COVID-19 infection, we use this data to predict whether or not viral concentrations are increasing or decreasing.

The red/sienna dots correspond to the actual observed viral levels of COVID-19 detected in Santa Cruz City, Santa Cruz County and Watsonville wastewater collection sites in units of copies per liter with a population weighted average. WEighted averages were used to adjust for changes in population coverage at each wastewater collection sites.  Learn more about wastewater by visiting the CDC's National Wastewater Surveillance System (NWSS) website. 

Notice the date range on the x-axis (line on the bottom of the graph). The area to the right of the current date are predictions and there are no observations reported in that area. The dark red line is the most likely level of COVID-19 in the wastewater in the future. Since models are not perfect, the light red wider area shows the range of likely virus levels. And the darker shaded area is the more likely range.

The yellow line is based from CDC’s recommended moderate community level threshold, or new cases greater than or equal to 200 per 100,000 people per week. The wastewater level corresponding to CDC's case-based moderate risk threshold was created by linking past COVID-19 case counts with the concentration of SARS-CoV-2 genes in wastewater. Specifically, this level estimate is based on wastewater level-to-case ratios in Santa Cruz County from April to November 2022.

SARS-CoV-2 Sewage Monitoring Data

SARS-CoV-2 (the virus that causes COVID-19) is shed in feces by infected individuals and can be measured in wastewater. More cases of COVID-19 in the community are associated with increased levels of SARS-CoV-2 in wastewater, meaning that data from wastewater analysis can be used as an indicator of the level of transmission of COVID-19 in the community.

Wastewater analysis measures the levels of non-infectious RNA (Ribonucleic Acid) in wastewater, not the viable virus. There are no known cases of transmission resulting from exposure to wastewater.

Advantages of WBE

The use of WBE has several potential advantages:
It includes asymptomatic individuals and people who are unable or unwilling to obtain clinical tests, for a variety of reasons.

It provides a mechanism to monitor the level of community transmission as clinical testing declines, and other, more convenient testing takes place (such as home-based rapid antigen tests) that are not reported to the Public Health Department. Wastewater analysis continues to be a part of our ongoing strategy to monitor the level of community transmission.

Wastewater information is available sooner than information from clinical testing, which means that monitoring SARS-CoV-2 in wastewater can serve as an early indicator of increasing or decreasing COVID-19 infections in the community.

During an increase, this early information could be used to enhance public health messaging in the affected communities to reinforce safe practices, promote more clinical testing, and highlight strategies the public can take to help stop a surge in new cases.
It can help confirm current trends of COVID-19 infections in the community that are based on clinical data.

It can increase confidence that clinical testing results are not biased by availability, time lags, and other factors.

Why We Monitor and Forecast Wastewater Data

Monitoring the concentration of the SARS-CoV-2 (COVID-19) virus in wastewater is a new way to know how much virus is spreading in the community. Wastewater monitoring includes those who haven't been tested. The COVID-19 virus is shed in the feces of infected people, including those who aren't experiencing symptoms. According to scientific research (click HERE to read the research), the viral concentration of COVID-19 in wastewater is highly linked to an increase in cases. When viral concentrations in the wastewater are increasing, then the risk for acquiring a COVID-19 infection from another person is increased.

 

Source: Center for Disease Control and Prevention (CDC) National Wastewater Surveillance System (NWSS). Viral concentrations of COVID-19, Influenza (flu), and RSV in wastewater samples reflect data from the City of Santa Cruz, County, and Watsonville Wastewater Treatment Plants. The Scotts Valley Wastewater Treatment Plant is not included due to the small population coverage for this sewer shed.

 

Update Frequency: Wastewater samples are collected a few times a week from the City of Santa Cruz, County, and Watsonville Wastewater Treatment Plants and the wastewater concentration plots are updated weekly. Please note: Update frequency is dependent on data availability from data source. Most recent data are preliminary and subject to change.

 

The data points included on the wastewater plot correspond to a 10-day rolling average concentration of virus for each respective wastewater treatment plant. The concentrations are “normalized” by the concentration of a plant virus that is harmless to humans but is shed in stool. This plant virus is the pepper mild mottle virus, or PMMoV. Normalizing by PMMoV adjusts for changes in the amount of feces in the sample and the efficiency of the procedures from day to day.

Hospitalization Data

Tracking hospitalizations from COVID-19, Influenza (flu), and RSV gives us a clear picture of how serious these illnesses are in our community. When more people are hospitalized, it can be an early warning that a virus is spreading more widely or causing more severe illness.

This information helps doctors, hospitals, and public health officials act quickly — like preparing hospital resources or issuing public health guidance — to keep our community safe and informed.

Source: The respiratory hospitalization data comes from the Centers for Disease Control (CDC) National Healthcare Safety Network (NHSN). 

 

Hospitalizations reflected in this data source include Watsonville Community Hospital, Dominican, and Sutter Maternity and Surgery Center.

 

Update Frequency: Hospitalization data for COVID-19, Influenza (flu), and RSV is updated once a week. There is typically a one-week delay between when hospitalizations occur and when the data becomes available. Please note: Updates depend on when the source data is reported to us. The most recent numbers are considered preliminary and may change as more information becomes available.

About COVID-19 Death Data

COVID-19 deaths in Santa Cruz County have dropped significantly since the start of the pandemic. Still, tracking deaths remains an important part of understanding the impact of the virus in our community.

Because deaths often occur weeks after someone becomes seriously ill, they tend to lag behind increases in cases and hospitalizations. This means that even when case numbers begin to decline, deaths may continue to rise for a short time.

Monitoring this data helps the Santa Cruz County Health Services Agency make informed decisions to slow the spread of COVID-19 and protect the health of our community.

Source: California Department of Public Health Vital Records

 

COVID-19 associated deaths reflected in this data include decedents who lived in Santa Cruz County and either passed away in or outside the county.

         

Update Frequency: Data is updated weekly. Please note: Update frequency is dependent on data availability from data source. Most recent data are preliminary and subject to change.

Influenza and RSV Death Data

Monitoring deaths from Influenza (flu) and RSV helps us understand how serious these viruses are each season — especially for vulnerable groups like young children, older adults, and people with underlying health conditions.

As with COVID-19, deaths from flu and RSV often happen weeks after someone gets sick. This means the number of deaths may continue to rise even after the worst of the outbreak has passed.

By tracking these trends, the Santa Cruz County Health Services Agency can better plan and respond to protect those most at risk.

Source: California Department of Public Health Vital Records

 

Influenza (flu) associated deaths and RSV associated deaths reflected in this data include decedents who lived in Santa Cruz County and either passed away in or outside the county.

 

Update Frequency: Data is updated weekly. Please note: Update frequency is dependent on data availability from data source. Most recent data are preliminary and subject to change.