Data collected through the One Health Harmful Algal Bloom System (OHHABS) can help CDC and partners better understand harmful algal blooms and prevent associated human and animal illnesses.

OHHABS is a CDC surveillance system launched in 2016. State and territorial health departments and their designated environmental health or animal health partners can voluntarily report data to OHHABS.

OHHABS collects data on:

  • Human illnesses
  • Animal illnesses
  • Harmful algal bloom events that occur in fresh, brackish, or salt waters

Data Summaries

Find OHHABS data by year in the reports below.

2021 Data
2021 OHHABS Data Summary PDF cover
2020 Data
2020 OHHABS Data Summary PDF cover
2019 Data
2019 OHHABS Summary Report