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COVID-19 Status Update for 12/02/2021

Marin County COVID-19 Status Update for December 2, 2021 includes Post-Holiday Testing Reminder; Public Health Shares Vaccine Lessons; and updated local COVID-19 data.… Read More

Novel Coronavirus (COVID-19)

Surveillance Update

Marin County Public Health tracks demographic, geographic, and clinical information about confirmed COVID-19 cases to inform the COVID-19 response and understand factors associated with COVID-19 transmission and clinical outcomes in our community. We are consistently improving our data collection, analysis, and sharing procedures, so will continue to add to this report as data become available. COVID-19 testing and case data are reported as timely, accurately, and completely as we have available. Data are updated as we receive information that is more complete and will change over time as we learn more (see FAQs). Information about confirmed COVID-19 cases is updated daily on weekdays by approximately 5pm Pacific Standard Time (PST).

Click on an icon below to navigate to that section of the dashboard:

As of January 5, 2021 this website now uses Tableau dashboards to visualize the impact of COVID-19 in Marin County. Under each dashboard there are links to datasets available on Marin County's Open Data Portal. To learn more about how to use the features of these dashboards navigate to the "How To Use this Dashboard" section of this website. 

As of March 6, 2021 the full Surveillance Website will not be updated on weekends. The summary numbers at the top of the page will continue to update (except testing), but other dashboards will only be updated Monday through Friday.

Key Indicators

This information shows how COVID-19 has impacted Marin County community residents since the first case. These data include facility patients and staff who live in Marin County. These data do not include San Quentin inmates. "Cases in Past 14-days" is calculated by adding up the total number of cases in the most recent 14-day period (no lag).

Cumulative Counts

Total Cases
(+27 change)
Cases in Past 14 Days
(+14 change)
Total Deaths
(+0 increase)
Total Residents Vaccinated*
(+253 increase)
Last Updated: 12.02.21 - 3:30 PM PST.
*Residents Vaccinated represents the number of Marin County residents who have received at least one dose of vaccine.

COVID-19 Cases

This chart displays the daily count and 7-day rolling average of new confirmed cases. Due to the time required for reporting, case data is lagged by 3 days. Positive cases may be under-reported for up to 10 days. The CDC now offers County-Level Community Transmission Rates, which are updated daily. Marin County Public Health is referring to this data to guide pandemic policies.

Data Source: COVID-19 Case Disposition

Prevalence of Variants of SARS-CoV-2 in Marin County

This chart displays the weekly proportion of COVID-19 variants of concern (VOC) identified through whole genome sequencing (WGS) in Marin County in 2021, by date the sample was collected. All other variants not classified as VOC by the CDC are grouped together in the "other" category. CDC definition of VOC can be found here. There is a minimum 7-day (and up to 21-day) lag in reporting, therefore results displayed represent only a fraction of sequenced results; this chart is updated weekly. Not all positive samples are sequenced, thus the proportions displayed here may not fully represent the prevalence of circulating variants in the community. Since current evidence suggests there is no significant difference in the characteristics of the many sublineages of the Delta variant, all sublineages of the Delta variant will now be collectively classified as Delta (as of 10/5/2021).

Data Source: Source: Marin HHS, California Department of Public Health, Napa-Solano-Yolo-Marin Regional Public Health Laboratory, academic partners, and commercial laboratories

COVID-19 Cases among Vaccinated and Unvaccinated Residents

This chart shows the daily average case rate per 100,000 residents. It compares rates between fully vaccinated and unvaccinated residents who had a new positive COVID test within the previous 7 days (changed from 14-day to 7-day average on 7/23/21). Residents are considered vaccinated two weeks after the final dose of the vaccine. As of 8/30/21, only residents who have received no doses are included in the unvaccinated category and residents who are partially vaccinated, meaning they only received one dose of a two-dose vaccine or who are not yet 14 days after their final dose, are not included in either category. Due to the time required for reporting, case data are lagged by 3 days. This includes all cases, regardless of symptoms.

COVID-19 Deaths

The chart displays the change in cumulative (total) COVID-19 deaths by death date. As of 10/25/2021, cumulative COVID-19 deaths will be updated on Fridays.

Data Source: COVID-19 Case Disposition

COVID-19 Hospitalizations

The Daily Census reflects COVID-19 patients currently in the hospital (lagged by one-day). Daily census values include patients from San Quentin and patients from other counties hospitalized in Marin County. Daily Census values do not include patients hospitalized at Kentfield Rehabilitation Hospital since it neither admits acute patients nor has ICU beds. The count of ICU patients is a subset of the total hospitalized patients. 

Data Source: CDPH Hospitalization Data

COVID-19 Testing and Percent Positivity

The following charts show the daily count and 7-day rolling average of testing volume and percent positivity. These data are collected and calculated by the California Department of Public Health (CDPH). Due to the time required for reporting, data is lagged by 3 days. Testing counts may be under-reported for up to 10 days.

Data Source: COVID-19 Tests (CDPH)

COVID-19 Population Characteristics

Demographics of Total COVID-19 Cases, Hospitalizations, and Deaths

The following charts show the proportion of total COVID-19 Cases, Hospitalizations, and Deaths by known Race/Ethnicity, Age Category, and Gender. Comparing demographic information for confirmed COVID-19 cases to the demographics in our community's population helps inform us about which groups may be more impacted by COVID-19.

Data Sources: COVID-19 Cumulative Demographics

Demographic Trends in COVID-19 Cases

The following charts show the 7-day moving average of new cases by Race/Ethnicity and Age Category. A 7-day moving average is calculated by adding the case counts by test date of 7 days together and then dividing by 7. The day displayed on the chart is the 7th day.

Data Sources: COVID-19 Cases by Race/Ethnicity, COVID-19 Cases by Gender, COVID-19 Cases by Age Category

Facility Staff and Residents

This table shows how COVID-19 has impacted residents of long-term care facilities in Marin County. Facilities include Residential Care Facilities (RCFs), Skilled Nursing Facilities (SNF), Independent Living (IL), and Other Group Living (OGL) facilities. Current positive staff and current positive patients include those who have tested positive for COVID-19 in the last 14 days. As of October 29, 2021, facilities data will be updated on Fridays.


COVID-19 Case and Vaccination Rates by Geography

Mapping cases by geographic regions helps us view where COVID-19 cases have been diagnosed in our community. The map below shows the cumulative and 30-day number of confirmed COVID-19 cases, cumulative and 30-day rates of COVID-19 cases per 100,000 residents, and vaccination metrics since March 2020. The numbers displayed on the map are the 30-day case rate per 100,000 residents. Note that the number of confirmed cases in a given community are reflective of testing. This map is interactive, click on each jurisdiction to view the name of the community/city, the total population for that area, the cumulative and 30-day number of COVID-19 cases, the cumulative and 30-day COVID-19 case rate per 100,000 residents, and COVID-19 vaccination metrics. Because the total population in one jurisdiction can be vastly different from another, the case rate per 100,000 residents helps us better understand the concentration of cases among the total population for that jurisdiction. This map is based on the residence provided by COVID-19 cases during the investigation process (also referred to as contact tracing). Communities with less than 10 cases do not have their case counts shared to ensure that individuals are not identifiable to the public. All data are subject to change as we may learn new information during a case investigation. As population estimates may not be precise, proportion vaccinated will only be displayed up to 98% for each census tract. If the map fails to load click here.

Marin County Public Health has routine quality improvement procedures in place to provide the most accurate and timely data as possible. Mapping procedures were updated in November 2020 to further improve our ability to report COVID-19 case counts by geographic location, including updating our methodology to account for corrections to case addresses throughout a case investigation. All cases reported for San Quentin only include those reported among community residents.

Geographic data are unavailable for approximately 5% of cases as a result of reporting delays or challenges.


COVID-19 Cases by City, Census Tract and Zip Code

This dashboard displays COVID-19 cases by city, census tract and zip code. Select the tab at the top to choose the area type (e.g. "City"), then select the specific area of interest (e.g. "San Rafael"). This will display the population of the area, cumulative cases, cases in the past 14-days (over-time) and a table with daily new cases in that area. Data is lagged by 3 days.

Data Source: COVID-19 Cases by Geography and Date

COVID-19 Vaccinations

As of March 19, 2021 there is a separate webpage to share Marin County COVID-19 Vaccination Data Dashboards.

Other Indicators

All-Cause Deaths

Looking at trends in all-cause deaths may help us to identify if we are seeing fewer or greater number of deaths than usual in Marin County. Seeing a sustained spike in the number of deaths occurring in a given week in 2020 compared to 2018-19 may demonstrate COVID-19's impact on Marin County. The line chart below shows the two-week rolling average of all-cause deaths among Marin County community residents by week in 2020 as compared to 2018 and 2019 combined. The date on the horizontal axis represents the last day in the two-week rolling average. Note this chart only includes deaths among Marin County community residents and does not include deaths among individuals incarcerated at San Quentin prison. Between January 1, 2018 to June 30, 2020 the two-week rolling average of deaths among people incarcerated in San Quentin was between 0-1. To view updated data on COVID-19 deaths among San Quentin COVID-19 cases, visit the California Department of Corrections website.

Respiratory-Illness Surveillance

As of January 5, 2021 this COVID-19 surveillance website no longer includes ED and EMS respiratory-illness charts. To view data on respiratory-illness surveillance visit the Marin Flu Surveillance Data webpage.

How to Use this Dashboard



  • For best viewing options across most devices select the "Full Screen" icon in the very bottom right hand corner of each dashboard.
  • Adjusting the Date slider above charts will modify the date range in the view; move the date sliders to the right or left with a mouse. This allows users to zoom into smaller periods of time.
  • To highlight particular features (lines/bars) in the charts, select an item in the legend either by clicking it with a mouse or tabbing to it and pressing the Spacebar.
  • To see the data behind each chart select the "Download" icon in the bottom right of the dashboard and select "Crosstab", then select the specific chart of interest. Full datasets are linked below each dashboard, directing the user to Marin County's Open Data Portal.   Another way to see a data table is to tab to put focus on a chart and then press Enter.



Every attempt has been made to enable the data visualizations accessible for keyboard navigation and screen readers. Tableau provides specific keyboard navigation instructions on their website. If you have a disability and need assistance with the information on this page, use the COVID-19 contact form to submit your access questions or call the state COVID-19 CA Hotline (833)422-4255.