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California Breathing​​​

Asthma Data

California Breathing analyzes asthma data from a variety of sources to better understand the burden of asthma in California. These data are summarized and made pub​licly available through infographics​ and various data tools including an interactive data dashboard and downloadable data sets. California Breathing aims to make asthma data informative to the public and its partners working to reduce asthma in California. ​​

Asthma in California Infographic

View the printer-friendly version of Asthma in California Infographic (PDF).​​

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What is ​As​​thma?

​A serious lung ​​disease that makes it hard to breathe. With proper treatment, asthma can be controlled.

Asthma symptoms include:

  • ​Wheezing
  • Coughing
  • Shortness of breath
  • Chest tightness​​​​

How many people in California have asthma?

Skip to main content ​​​​1 in 7 Californ​ians​​ hav​e asthma

​​​​Each year, asth​​ma causes:

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145, 000 
emergency room visits​
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15,000 
hospital stays​
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364 
deaths​

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1 in 3 
children with asthma to miss schoo​l​​
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1 in 5 
adults with asthma to miss work​

​Asth​ma costs $1​4.5 ​billion per year including:​


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me​​dical expe​n​​ses
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​premature deaths
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missed school days
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missed work days


Source: California Health Interview Survey (2024); California Department of Health Care and Information (2024); California Department of Health Public Health Vital Records (2024); Nurmagambetov, Kuwahara, Garbe (2018) Annals of the American Thoracic Society 15: 348-356; Barnett, Nurmagambetov (2011) Journal of Allergy and Clinical Immunolog127: 145-152​

Data Tools and Resources​​

Tracking California’s Data Explorer Tool​

Tracking CA Data Explorer Icon.jpg 

​​​Asthma Data in Tracking California’s Data Explorer Tool – Due to shrinking federal funds, California Breathin​g will no longer host the California Asthma Dashboard. California Breathing is partnering with Tracking California, a program of the Public Health Institute that mobilizes data to identify and understand pollution and disease, to provide asthma data through an interactive online data tool called the Data Explorer Tool​​. The Data Explorer Tool p​rovides the following county and zip code-level asthma measures: 

  • ​Asthma prevalence 
  • Asthma emergency department visits, hospitalizations, and insurers 
  • ​Asthma deaths 

​California Health and Human Services Open Data Portal 

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Asthma data sets are available for download from the California Health and Human Services (CHHS) Open Data Portal. Download state- and county-level data on: 

Additional Data Resources

Additional asthma information is available from these sources:

  • CalEnviroScreen (emergency department visits by census tract)
  • AskCHIS (prevalence, work and school days missed, use of daily controller medication, and development of asthma action plan by county)
  • AskCHIS Neighborhood Edition (prevalence by zip code and other small geographic areas)

Custom Data Request

If you are seeking asthma data that are not available from any of the resources list above, please send your request to California.Breathing@cdph.ca.gov and we will contact you regarding the possibility of creating a customized data set. It is not always possible to fulfill custom requests, but each request will be considered.​

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