Havana syndrome

Havana syndrome
Other names	Anomalous health incidents[1] Unexplained health incidents[2] Unidentified health incidents[3]
The Hotel Nacional in Havana is one of the locations where the syndrome was reported.[4]
Causes	Not determined[5][6]
Named after	Havana (Capital City of Cuba)

Havana syndrome, also known as anomalous health incidents (AHIs), is a disputed medical condition. It is not officially recognized as a disease by the medical community. Starting in 2016, U.S. and Canadian government officials and their families reported symptoms of AHIs in about a dozen overseas locations. Reported symptoms include a sudden onset associated with a perceived localized loud sound, followed by chronic symptoms that lasted for months, such as balance, dizziness, cognitive problems, insomnia, and headaches.

The U.S. government has established a variety of programs providing medical and financial support to persons that reported AHI symptoms, but some AHI patients continue to campaign for additional support.

A number of government and non-government agencies have conducted investigations into the AHIs, including the State Department (2018), University of Pennsylvania (2018), FBI's Behavioral Analysis Unit (2018), JASON (2018 and 2022), Centers for Disease Control (2019), Department of Defense (2020), Central Intelligence Agency (CIA) (2020), National Academies of Sciences, Engineering, and Medicine (NASEM) (2020), Cuban Academy of Sciences (2021), seven intelligence agencies under the auspices of the Office of the Director of National Intelligence (ODNI) (2023), and National Institutes of Health (NIH) (2024). Several news organizations also conducted investigations.

None of the investigations has been able to determine the cause with certainty. Investigators consider energy weapons and psychological/social issues to be possible causes; but determined that toxic chemicals and infectious diseases are unlikely to be causes.

The most recent and thorough investigations determined that foreign adversaries are unlikely to be the source of AHIs. The use of energy weapons was determined to be consistent with the reported AHI symptoms, but no direct causal relation has been established, partially because there is little experimental research on the impact of energy weapons on the human brain. Recent medical research has not found statistically significant evidence of brain injuries in AHI patients. Some investigations stated that it is difficult to prove or disprove if psychological/social factors are responsible for AHI symptoms, but some researchers stated that psychological/social factors are a potential cause; and, if there is another primary cause for some symptoms, that psychological/social factors may be a secondary, contributing cause.