One Health Harmful Algal Bloom System (OHHABS)

The One Health Harmful Algal Bloom System (OHHABS) collects information to help CDC and partners better understand harmful algal blooms (HABs) and help prevent human and animal illnesses caused by HABs.

One Health Harmful Algal Bloom System logo


OHHABS is a voluntary reporting system available to state and territorial public health departments and their environmental health or animal health partners.

OHHABS collects data on:

  • Human illnesses caused by HABs
  • Animal illnesses caused by HABs
  • Environmental data about HABs

OHHABS is a One Health surveillance system. A One Health approach recognizes that the health of people is connected to the health of animals and our shared environment. This connection requires many types of partners to work together to improve health for all.

Find data on the OHHABS Data webpage.

Communication Resources
Example HABS communication materials

Public health professionals can use our health promotion materials and OHHABS partner toolkit to share information with interested groups, including:

  • The public
  • Physicians
  • Veterinarians
  • Other partners
Wading blue heron in a green river polluted with algae

CDC launched OHHABS in 2016 to better understand HABs and help prevent illnesses that HABs can cause in people and animals. Learn more about OHHABS:

  • Why do we need OHHABS?
  • How did OHHABS start?
  • What can be reported in OHHABS?
  • Is OHHABS real-time?
  • Where do I find national HABs and illness surveillance data?
  • How can I support One Health HAB surveillance?
U.S. map with a magnifying glass over it

Staff at state and territorial agencies report to OHHABS. Resources for OHHABS users include:

  • Forms for collecting information to report in OHHABS
  • Guidance on how to use OHHABS and complete reports
  • How to start reporting in OHHABS
  • Resources to share OHHABS and HABs information
Page last reviewed: September 30, 2021