Anomalous health incident, or AHI, is the term used to describe a constellation of unexplained and sudden symptoms, and the Defense Health Agency’s National Intrepid Center of Excellence and the Traumatic Brain Injury Center of Excellence have developed an assessment tool to evaluate patient symptoms and better understand AHI.

The new tool helps providers who find “no clear, attributable cause” for these symptoms with a structured assessment of those reporting an anomalous health incident, otherwise known as “Havana syndrome,” according to Dr. Louis French, NICoE’s deputy director.

These symptoms may include headache, confusion, memory concerns, pain, nausea, hearing, dizziness, balance issues, or sleep disturbances. Additional signs or sensory phenomena may consist of hearing loud sounds, the feeling of pressure, experiencing vibrations or the sensation of heat during or immediately before the start of these symptoms, according to U.S. Navy Capt. (Dr.) Scott Cota, TBICoE branch chief. These symptoms can lead to a condition similar to a post-concussion syndrome, he said

DHA is actively training medical personnel to detect and assess AHI as close to an incident as possible. Cota’s TBICoE team is leading the virtual acute assessment training. The next session is scheduled for Sept. 21, 2023.

The training is available through DHA’s  Continuing Education Program Office and is open to all health care providers. It introduces AHI and reviews assessment and treatment strategies. The training provides detailed guidance on how to complete a medical evaluation using DHA Form 244.

“DHA Form 244, or the Anomalous Health Incident Acute Assessment Form, was designed to acutely assess (within seven days) individuals reporting symptoms believed to be an AHI,” said U.S. Navy Capt. (Dr.) Carlos Williams, NICoE’s director and co-chair of the AHI integrated planning team.

“The form was designed to provide clinicians a structured way of evaluating individuals presenting for assessment and care. The form is not intended to take the place of clinical judgment or other assessments that the clinician may think important,” Williams emphasized.

Since a sudden onset of symptoms such as these can be related to a number of causes, such as stroke, infection, concussion (mild TBI), or COVID-19, among others, it is important that a medical evaluation be done as soon as possible, French said.

DHA Actions on AHI

While there is no definitive cause yet for AHI nor its impact on the brain, DHA has been working to better understand the phenomenon, which was first reported by U.S. personnel assigned to the United States Embassy in Havana, Cuba, in 2016.

There have been subsequent events reported by Department of Defense personnel, families, and civilian employees, mostly overseas.

A Jan. 13, 2023, report to Congress on AHI/Havana syndrome from Undersecretary of Defense Gilbert R. Cisneros Jr. outlines actions the DOD has taken so far. These include:

• Establish of a cross-functional team for AHIs
• Publish updated clinical guidance for evaluation and treatment
• Utilize NICoE resources to evaluate and treat AHI patients
• Develop of DOD guidance on providing access to medical hospitals and clinics for current and former government employees, service members, and their respective families with AHIs
• Establish and maintain a clinical registry

The registry, currently in development, will “provide future clinicians and researchers information to better understand AHI and will include data on the circumstances of the incident, presenting symptoms, results of initial assessments including DHA Form 244, as well as other clinical information,” explained U.S. Army Col. (Dr.) Ingrid Mulkerrin, DHA Clinical Support Division deputy and co-chair of the AHI integrated planning team.

The registry data “will be related to information around the incident and not details of later care or the course of treatment and outcome,” she said. Most cases of AHI resolve quickly on their own or with treatment, French said.

"At NICoE and throughout the Defense Intrepid Network for TBI and Brain Health, we use a patient-centered, holistic, interdisciplinary approach for the assessment of patients affected with TBIs, AHI and other associated conditions. The interdisciplinary model ensures patients have access to primary care providers, as well as specialties such as neurology, audiology, behavioral health, neuro-optometry, and physical therapy,” Williams said.

How to Report an AHI and Where to Get Help

“If you think you may have been exposed [to an AHI], then report it to your command,” French advised. “Your chain of command will help you get appropriate medical care or a referral to NICoE, if indicated.”

A Sept. 15, 2021, memo from Secretary of Defense Lloyd J. Austin III details the reporting chain.

“If you suddenly develop these symptoms, go immediately to an emergency health care provider. It is critical that medical emergencies be ruled out before assigning these symptoms to AHI,” Williams explained.

DHA’s Defense Intrepid Network for TBI and Brain Health has a network of TBI specialty care clinics at 13 locations across the U.S. and overseas that include the National Capitol Region’s National Intrepid Center of Excellence and Intrepid Spirit Centers.

“Our goal is to maximize recovery of those we treat, regardless of the root cause,” French said. “For those AHI patients whose symptoms diminish their quality of life, we work to ameliorate that.”