Some experts assert that Havana Syndrome is a classic case of mass psychogenic illness (MPI) not real injury.

There is some overlap of symptoms with MPI (e.g. headache) and social contagion may be a viable vector.

However, MPI does not explain much of the data from studies of victims, and remains an unproven hypothesis.

Havana Syndrome, also known as anomalous health incidents (AHIs), represents a cluster of acute and chronic neurological symptoms such as headache, imbalance, vertigo, and cognitive problems. [1]

Two prestigious expert panels, one from the National Academies of Sciences, Engineering, and Medicine and another from the Intelligence Community, concluded that pulsed radiofrequency energy could plausibly account for some distinctive AHI symptoms. [2, 3]

However, the expert panels were unable to pinpoint an exact mechanism of injury. Moreover, although some medical studies reported objective differences in AHI patients, others did not. [4, 5]

The lack of clarity about the cause of AHI symptoms and the inconsistent results led some experts to assert that AHI represents a case of mass hysteria, formally known as mass psychogenic illness (MPI). [6]

What is Mass Psychogenic Illness (MPI)?

MPI is the rapid spread of physical symptoms through a cohesive social group in the absence of an identifiable organic cause, propagated by visual, verbal, or media transmission of belief and anxiety. [7]

MPI spreads through social networks rather than according to proximity to a source, with a predominance among females and younger people. Typically, the index case is someone with high status or visibility. [7]

Common symptoms include headache, dizziness, nausea, hyperventilation, fainting, chest tightness, weakness, paresthesias, and abdominal pain. Motor forms add tremor, tics, psychogenic seizures, gait disturbance, and dysphonia. [7]

Four examples cited in the literature are:

Tanganyika laughter epidemic, 1962 — uncontrollable laughing and crying spread through mission schools for months, forcing closures. [8]

West Bank schoolgirls, 1983 — nearly 1,000 Palestinians, mostly girls, reported fainting, headache, and abdominal pain; competing allegations of poison gas circulated, but investigators found no toxic cause. [9]

Le Roy, NY, 2011–12 — Tourette-like tics emerged among high-school girls; environmental hypotheses were investigated, and social media may have contributed to the spread. [10]

Contemporary “TikTok tics” (2020–21) — functional tic-like behaviors were reported in young people during a period of extensive social-media exposure, showing that the “group” need not be physically co-located. [11]

MPI researchers describe underlying psychological mechanisms that include: [7]

The nocebo effect (experiencing an adverse result one expects)

Heightened attention to interoceptive cues, amplifying ordinary sensations until they seem pathological

Acute stress and autonomic arousal, with subsequent reactions interpreted as signs of illness

Automatic, unconscious mimicry and “social contagion”

A compelling narrative: “Y caused X.”

The case for MPI causing Anomalous Health Experiences

Medical sociologist Dr. Robert Bartholomew and neurologist Dr. Robert Baloh argue in their book, Havana Syndrome: Mass Psychogenic Illness and the Real Story Behind the Embassy Mystery and Hysteria, that AHI is a classic example of MPI. [6]

Indeed, there is........

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