When the detailed clinical manifestations of Havana syndrome emerged in February 2018, courtesy of Dr Douglas H Smith and his team’s preliminary paper in The Journal of the American Medical Association (JAMA), the acoustic-weapon theory was already being quietly discarded by the inside investigators – not least, perhaps, because very few of the later victims were reporting any odd noises along with their symptoms. The final blow to the ‘sonic brain gun’ hypothesis was delivered after the Associated Press leaked what was thought to be Patient Zero’s recording of the sound that had targeted him. Expert analysis established that this noise had been created by chirping crickets or cicadas. The only way a cicada could really damage your hearing, biologist Allen Sanborn said, is if ‘it was shoved into your ear canal’.

In early 2018, an FBI investigation effectively ruled out any sort of sound attack. In response, some pointed a finger at microwave radiation, an explanation that received official back-up in December 2020 when a National Academies of Sciences report concluded that ‘among the mechanisms the committee considered, directed, pulsed radio frequency energy [a category that includes microwaves] appears to be the most plausible mechanism in explaining these cases, especially in individuals with the distinct early symptoms’.

Experts of different stripes queued up to undermine this suggestion. Neurologists wondered how – in defiance of accepted medical knowledge – microwaves could selectively target the brain alone. At the very least, says O’Sullivan, any such microwaves would also scorch human skin. Physicists and engineers asked if it was seriously feasible that anyone could have developed a weapon of such potency – let alone one that, to fit the Havana scenarios, would need to be readily portable and totally undetectable, while somehow sparing the brain of its proximate operator. Bioengineer Kenneth Foster had told The Washington Post that the concept was ‘crazy’. ‘Any kind of exposure you could give to someone that wouldn’t burn them to a crisp would produce a sound too weak to have any effect.’

Defence insiders maintained that the Pentagon, and to a lesser extent the Russians, had long since given up attempting to develop microwave and sonic weapons – though not through lack of effort or investment. Could impoverished Cuba really have succeeded where the superpowers failed? And even if it somehow had, why on earth attack low-level embassy functionaries alongside CIA officers, let alone Canadians – nationals of a country with which Cuba enjoyed a largely cordial relationship?

The JAMA paper would prove endlessly controversial. Seeing one of the world’s most respected medical journals give apparent credibility to the notion of some sort of energy attack, 15 eminent neuroscientists and physicists published an open letter that decried the work as ‘deeply flawed’, and urged ‘qualified people’ to ‘evaluate evidence without political pressure to draw poorly founded conclusions’. JAMA itself felt the need to run dissenting articles in later issues, and to publish an editor’s note that poured cold water on the Smith team’s headline follow-up evidence: a set of MRI scans that purportedly showed differences in regional brain volumes in a group of 40 US government personnel who had experienced symptoms, compared to a control group. Such scans are notoriously open to interpretation, and the editor’s note stated that ‘the clinical relevance of these differences is uncertain’.

Anyway, to many in the mainstream medical community, the mystery of Havana syndrome wasn’t a mystery at all.

In late 2017, something strange happened at a high school in Dewey, Oklahoma. About 20 students were afflicted with spasms and seizures, with some left unable to move or talk. The state health department conducted a battery of tests that eliminated contagious infection, and found no trace of environmental contaminants. As the victims gradually recovered, the school superintendent sent parents a letter that communicated the ‘diagnosis of the medical community’: the students had been affected by a ‘conversion disorder, which is of psychological nature, and we understand that symptoms are in response to stress and anxiety’.

In truth, what happened at Dewey wasn’t so strange. Outbreaks of conversion disorder, also referred to as mass psychogenic illnesses (MPIs), have been part of the human experience throughout recorded history, documented in vast numbers. New Zealand-based medical sociologist Dr Robert Bartholomew, author of multiple books that cover what used to be called ‘mass hysteria’, has identified more than 3,500 cases. ‘Think of mass psychogenic illness as the placebo effect in reverse,’ he says. ‘You can often make yourself feel better by taking a sugar pill. You can also make yourself feel sick if you think you are becoming sick. Mass psychogenic illness involves the nervous system, and can mimic a variety of illnesses.’

The phenomenon came to prominence in the Middle Ages, when periodic outbreaks of ‘dancing mania’ afflicted towns and cities in Europe. In July 1518, a solitary Strasbourg woman started a jig that begat two months of helpless civic cavorting in which dozens died of heart attacks and exhaustion. Nuns at a French convent started mewing like cats; German villagers bit each other for weeks. The infamous Salem witch trials of 1692-93 were catalysed by an outbreak of alarming convulsions and fits that are now generally accepted as manifestations of an MPI.

The industrial revolution sparked a rise in MPIs around the world, with groups of factory workers succumbing to screaming bouts, dizziness, trance-like states and panic attacks. But scientific appreciation of such episodes – and their detailed medical analysis – only evolved after the Second World War. In June 1962, more than 60 workers at a textile factory in the US South developed rashes, nausea and numbness that they attributed to insects from a fabric shipment. When entomologists found no trace of a culprit, psychologists who interviewed the victims made a pioneering diagnosis of what we would now call an MPI, noting that of the 62 victims, 59 worked on the same shift, and 50 only reported symptoms after the start of a media feeding frenzy on the ‘June bug plague’.

Schools, though, have established themselves as particularly fertile territory for mass psychogenic illness. In 1962, a ‘laughter epidemic’ affected 1,000 pupils at 14 schools in what is now Tanzania. A sudden outbreak of teeth-chattering and dizziness saw 85 children at a single Blackburn school taken to hospital one morning in 1965. Almost 250 student performers succumbed to headaches, dizziness and in some cases fainting at a 1989 concert in Santa Monica. All of these incidents, and hundreds more, have now been confidently attributed to mass psychogenic illness.

Perhaps most pertinent to this story is the tale of ‘Bin Laden Itch’, a rash that afflicted thousands of US schoolchildren in late 2001 and 2002. After a man in Florida came down with anthrax, the terrorist fears that had gripped the nation since 9/11 built to a wave of paranoia. Pupils across North America developed itchy red patches, via outbreaks that spread through individual schools in a matter of hours. Some 238 children were affected in one small Pennsylvania town alone. But the symptoms never progressed, and the rashes faded as mysteriously as they had developed. What had been responsible?

A public-health nurse who had dealt with a similar itching outbreak in a Canadian school in early 2001, and was contacted by a counterpart investigating cases in the US, said that in those Canadian cases mass psychogenic illness was ‘one of our hypotheses’. She admitted, though, that she had never shared this with affected children or their parents. ‘People seem to deal better with concrete facts,’ she went on. ‘You really don’t like to cast that shadow.’

For Bartholomew, this reluctance – born of the stigma that remains stubbornly attached to psychosomatic ailments – lies at the heart of the Havana syndrome story. He notes that although Smith’s team considered conversion disorder, they dismissed it after screening the first test subjects for ‘evidence of malingering’ – in other words, faking it.

‘There was not one individual on the team who was not convinced this was a real thing,’ Smith said. He continued, ‘To artificially display all of these symptoms, you’d have to… be the most consummate actor ever.’ Bartholomew remains bewildered by these words, which seem to equate psychogenic illness with shirking and deception. Malingering, he says, disappeared from the medical literature ‘about 60 years ago’.

Yet Smith’s opinion was, and still is, shared by every doctor who met those ‘first wave’ Havana victims. Professor James Giordano, chief of neuroethics studies at Georgetown University and executive director of the Institute for Biodefense Research, headed the third medical team the US government commissioned to investigate. Giordano, another ex-military officer, insists that these original cases exhibited ‘clinically relatable and evidentiary signs that were indicative of neurological trauma’, with a ‘high probability’ that these were inflicted by a ‘directed energy’ weapon – perhaps ‘some form of rapidly pulsed, low-gigawatt microwave energy’. He also suggests there was a ‘defined pattern’ to the early incidents, though for security reasons he is ‘not at liberty to discuss what that pattern is in terms of who was being targeted’. (Outsiders investigating Havana syndrome often find lines of inquiry blocked off by a wall of official secrecy.)

Giordano arrived at these conclusions by applying what he describes as ‘abductive forensics’, a process that seeks the likeliest, most simple explanation from any set of observations. But if, like O’Sullivan, Bartholomew and the medical community in general, you see no concrete evidence of brain damage in these observations, Giordano’s answer would be some way from the most probable. Psychogenic illnesses are extremely common, O’Sullivan emphasises – one study suggests that up to a third of neurology referrals relate to a psychosomatic complaint – whereas directed-energy weapons absolutely are not. ‘How was an everyday diagnosis sidelined for one that many thought impossible?’ she asks. ‘When you hear hooves,’ says Bartholomew, quoting an old medical maxim, ‘think horses, not zebras. The State Department looked for unicorns. They were going for the most exotic hypothesis.’