Anomalous Health Incidents

The Department of Defense and Defense Health Agency are committed to preventing, treatment, and recovering patients who report symptoms of an Anomalous Health Incident. DHA is actively developing a standard care pathway for both DOD and non-DOD beneficiaries to receive appropriate medical care as quickly as possible. To support this, patient resources have been developed to provide information on how to seek medical attention within the Military Health System and an overview of medical care coverage. Additionally, multiple provider resources are available to support care management and ensure proper documentation of treatment. This site will continue to be updated with products, trainings, and resources as they become available.

Overview and Symptoms

Previously referred to as Havanna Syndrome or as an Unconventional Brain Injury, AHI is the term used to describe a group of sudden symptoms that occur after an unexplained sensory event or events that are not associated with a history of head trauma. AHI events have been reported by several DOD and Federal Agency personnel since 2016.

Possible symptoms that are associated with an AHI event may include but are not limited to:

  • Auditory Symptoms
  • Balance Problems 
  • Cognitive complaints 
  • Difficulty concentrating
  • Head Pressure
  • Headache
  • Hearing Changes
  • Memory Problems 
  • Nausea
  • Dizziness

You also may be interested in...

Fact Sheet
Mar 10, 2025

Anomalous Health Incident Factsheet

.PDF | 514.81 KB

AHI is the term used to describe a series of unexplained and sudden symptoms associated with the acute onset of a sensory event, such as pressure, heat, loud sounds, or other auditory phenomena.

Fact Sheet
Mar 10, 2025

Medical Pathways Factsheet

.PDF | 294.96 KB

Durable Medical Equipment is a term for reusable devices or equipment prescribed by a provider for a patient’s use to support a related medical condition

Fact Sheet
Feb 13, 2024

AHI Patient Registry Frequently Asked Questions Fact Sheet

.PDF | 188.13 KB

The Department of Defense Trauma Registry is a web-based data collection tool that captures and documents, in electronic format, information about the demographics, injury-producing incident, diagnosis and treatment, and outcome of injuries sustained by U.S./Non-U.S. military and U.S./Non-U.S. civilian personnel in wartime and peacetime from the point ...