Havana syndrome: What It Is, Symptoms, Theories & More

Did you know that a handful of U.S. diplomats started hearing a strange "buzz" and feeling dizzy, as if a sudden wave hit their heads, while stationed in Havana, Cuba? That puzzling cluster of complaints is now called Havana syndrome, a term that still raises more questions than answers.

Below you'll get the quickfire rundown: what people actually feel, how many have been affected, the leading ideas about why it happens, and what doctors and governments are doing about it. No fluff, just plain facts and a friendly walkthrough, so you can understand this mysterious health incident without wading through endless jargon.

What Is Havana syndrome

The phrase "Havana syndrome" first appeared in late 2016 when U.S. embassy staff in Cuba reported sudden, unexplained neurological symptoms. It's not an official medical diagnosis; rather, it's a shorthand for a set of puzzling, often disabling complaints that have popped up in embassies, military bases, and even private homes around the world.

According to a public statement from the U.S. State Department, the incidents are "unexplained health events" that have affected personnel in at least a dozen countries. The National Academies of Sciences, Engineering, and Medicine released a comprehensive review in 2020, describing the syndrome as a "cluster of neurological and auditory phenomena" whose cause remains uncertain.source

Common symptoms

People who report Havana syndrome describe a strikingly similar set of acute and chronic signs. Below is a quick checklist that many clinicians use to spot the condition.

Symptom	Acute (first days)	Chronic (weeksmonths)
Buzzing or highpitch sound
Pressure/vibration in head
Ear pain or ringing (tinnitus)
Dizziness / loss of balance
Headaches
Memory lapses / concentration trouble
Sleep disturbances

These symptoms can appear suddenly, sometimes after a single "event," or they can develop gradually over weeks. The intensity varies widelysome people recover within days, while others cope with lingering fatigue and balance problems for months.

Who's affected

Official tallies are a moving target, but the numbers give you a sense of scale. The State Department reported 26 cases in 2017, which grew to over 200 by 2021, and a Government Accountability Office (GAO) review in 2024 counted 334 qualified cases among U.S. personnel.source Most of those affected are diplomats, intelligence officers, and military healthsystem patients, but a handful of family members have also reported similar signs.

Geographically, the incidents have clustered in a few hot spots: Havana (obviously), Guangzhou in China, Vienna, and several U.S. bases in the Middle East. A simple world map would show a dotted line connecting these points, underscoring how the phenomenon seems to pop up wherever U.S. officials gather for extended periods.

Possible causes

Scientists have tossed around a handful of theories, each with its own set of supporters and skeptics. Below is a sidebyside comparison that helps make sense of the debate.

Theory	What It Says	Key Evidence	Major Criticisms
Directedmicrowave weapon	Highfrequency RF energy focused on a person can cause neurological disruption.	National Academies (2020) called it "most plausible" among physical explanations.	No direct measurements of microwaves at incident sites; NIH 2024 study found no brain tissue damage.
Sonic / ultrasound	Infrasound or ultrasonic waves create pressure sensations and vestibular disturbance.	JASON report (2018) showed certain insect chirps can mimic the "buzz."	Acoustic levels measured during investigations were well below harmful thresholds.
Psychogenic (masspsychogenic) illness	Stress and suggestion trigger real physical symptoms without an external agent.	Bartholomew (2023) highlighted similar patterns in historic "cough" epidemics.	Doesn't fully explain the acute pressurelike sensations reported by many.
Toxic / chemical exposure	Unknown chemicals or pesticides could irritate the nervous system.	Some early investigations looked at pesticide residues.	Lack of consistent chemical signatures across sites.

So, is there a single culprit? Not yet. The truth is probably a mix of factors, and the scientific community continues to sift through data, hoping to find a clear thread.

Government response

When something this odd shows up in diplomatic circles, the U.S. government can't stay silent. Since 2018, the State Department has run a dedicated task force, coordinating with the Department of Defense, the CIA, and civilian researchers.

The Department of Defense opened a "Medical Surveillance" program in 2020, offering specialized vestibular testing and mentalhealth support to service members who meet the case definition. Meanwhile, the CDC produced an internal briefing in 2019 that concluded "no single environmental exposure has been identified."source

Internationally, Canada, the United Kingdom, and several European ministries have launched their own inquiries, largely mirroring the U.S. approach: gather medical records, run acoustic and electromagnetic surveys, and publish their findings when possible.

Diagnosis & treatment

If you suspect youor a loved onemight be experiencing Havana syndrome, the first step is a thorough medical workup. That usually includes:

• Brain MRI and CT scans to rule out structural damage.
• Comprehensive vestibular (balance) testing.
• Neuropsychological assessments for memory and concentration issues.
• Blood work to screen for toxins or infections.

Because there's no "cure" per se, treatment focuses on managing each symptom:

• Physical therapy and vestibular rehabilitation can help restore balance and reduce dizziness.
• Cognitivebehavioral therapy is often recommended when anxiety or psychogenic factors are prominent.
• Pain management for persistent headaches or ear discomfort, sometimes using overthecounter NSAIDs or prescribed muscle relaxants.
• Sleep hygiene practices for those battling insomnia.

U.S. officials who qualify can tap into Department of Defense health services or State Department assistance programs, which include counseling and financial support for ongoing care.

Looking ahead

The mystery isn't going away any time soon. Researchers call for larger, controlled studies that can capture exposure data in real timesomething that's been difficult given the sensitive nature of diplomatic postings.

On the policy side, embassies are reexamining building designs, adding shielding where possible, and training staff to recognize early warning signs. Media coverage continues to shape public perception, and the label "mysterious health incidents" reminds us that uncertainty can be unsettling, but it also drives scientific curiosity.

One thing's clear: while we may not yet know the precise cause, the lived experiences of those affected are real, and they deserve thorough investigation, compassionate care, and a clear line of communication from authorities.

Conclusion

Havana syndrome sits at the crossroads of medicine, physics, psychology, and geopolitics. It's a reminder that the world can still surprise useven in the most routine of diplomatic duties. By staying informed, supporting ongoing research, and encouraging anyone who feels these symptoms to seek professional help, we all play a part in turning this puzzling episode into a wellunderstood health issue.

If you've read this far, thanks for hanging out with me! What do you think about the leading theories? Have youor someone you knowexperienced any of these symptoms? Drop a comment, share your thoughts, or ask a question. Let's keep the conversation going and help each other make sense of these mysterious health incidents.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.