Infectious Diseases in California

Infectious Diseases prevalence is the number of people impacted by infectious diseases in a neighborhood. It combines the impact of all common and emerging pathogens such as influenza, COVID-19, RSV, measles, bird flu, insect-borne illnesses and more into a single score. It gives an idea of how many people are sick in an area at a given time.

Infectious Diseases prevalence in California is reported as the peak weekly score of how many people are impacted in a neighborhood, on a five-point scale: Low (<5), Moderate (5–15), High (15–25), Very High (25–40) and Extreme (>40). The score reflects the highest number of people impacted by Infectious Diseases across neighborhoods in the state, validated against public health data from CDC, HHS, EPA, NOAA, and other authoritative sources. Methodology details are available at https://www.hubbubworld.com/intelligence#methodology.

Hubbub develops proprietary models on top of geographic, demographic, environmental, surveillance and weather data to produce prevalence scores across the U.S. Prevalence is reported on a five-point scale (Low, Moderate, High, Very High, Extreme) so the scores are interpretable without needing the raw underlying numbers. The full methodology — including the modeling approach, validation against authoritative sources, and known limitations — is documented at https://www.hubbubworld.com/intelligence#methodology. The health risk data on the Hubbub website is for informational purposes only and does not constitute medical advice. Always consult a healthcare professional for personal health decisions.

Current Infectious Diseases risk levels, forecasts and alerts for California are exclusive to the bub app, available free on iOS, Android, and Apple Watch at https://bub.hubbubworld.com. This web page is the 4-week historical archive of prevalence — the bub app is where today's data and forecasts live.

Several of the risks Hubbub tracks have a seasonal pattern in California — flu and RSV typically peak in fall and winter, allergies vary with tree, grass, and weed pollen seasons, and severe weather risks shift with the seasons. Infectious Diseases prevalence in California is reported weekly, so seasonal patterns are visible across the 4-week archive on this page. For forecasts that show how seasonal patterns are evolving, get the bub app at https://bub.hubbubworld.com.