Public health,politics and the stigma of mass hysteria: lessons from an outbreak of unusual illness

In his biography of Sir William Phips, the first royal governor of the Massachusetts Bay Colony, Cotton Mather writes that in late 1691, the colony’s inhabitants became preoccupied with books on sorcery and fortune-telling. He observed that many people were practising ‘detestable Conjurations with Sieves and Keys, and Pease [peas], and Nails and Horseshoes’ in hopes of divining future events and forbidden knowledge. ¹ Local Minister John Hale had also expressed concern after having been informed that a young Salem girl had placed an egg white in a glass of water in order ‘to find her future Husbands Calling’. The girl reportedly became frightened after peering into the glass and seeing ‘the likeness of a coffin’. ² At the same time, a group of girls had been meeting in secret with a Barbados slave woman named Tituba, who recounted scary tales from Caribbean folklore. Amid this backdrop of superstition and fear, beginning in January 1692, a strange ailment swept through the devil-fearing Puritan settlement, almost exclusively afflicting young girls who exhibited convulsions, disordered speech and trance-like states. Salem physician William Griggs is believed responsible for rendering the diagnosis of bewitchment, transforming the ailment from a medical issue to a legal one, as the girls were viewed as the victims of a crime (witchcraft). His misdiagnosis laid the foundation for a wave of fear and accusations that plunged the community into crisis and resulted in 20 executions. ³ With 21st century hindsight, there is a consensus that the girls were suffering from conversion disorder. It is with no small irony then, that five centuries after these events, a similar outbreak affecting primarily young girls, occurred in old Salem village (now Danvers, MA).

On 29 January 2013, the Salem News first reported on two unusual illness outbreaks at separate co-educational vocational schools situated 3.5 miles (5.6 km) apart by road. These catchment schools serviced students from a broad region of the northeastern part of the state who were bussed in daily to receive specialist training. It said that during November 2012, a cluster of vocal tics and repetitive hiccupping had afflicted several students at North Shore Technical High School (NSTS) in Middleton, Massachusetts (pop. 8987 in 2010), and that by the time of publication, the symptoms had subsided. It further noted that a second cluster of similar symptoms had appeared in over a dozen students at Essex Agricultural and Technical High School (EATS) in the adjacent town of Danvers (pop. 26,493 in 2010). The Massachusetts Department of Public Health (MDPH) would later report that about two dozen students from the schools were affected, but by the time the department investigated, the number of cases at North Shore had dropped to one, and the number at Essex Aggie had risen to 18. ⁴ As a result, subsequent media releases on the outbreak are misleading as they refer to 19 cases at the two schools. Of this figure, 18 were girls attending Essex Aggie; one was a boy from North Shore. The affected students ranged in age from 14 to 18; all but one participated in school sports. If we count the ‘handful of incidences’ in other North Shore students whose symptoms subsided prior to the initial news report, those affected in both schools was approximately 24. ⁵

A symptom spreadsheet provides data on the onset of vocal tics in 17 of the 19 students. Of these, one had experienced daily vocal tics since 2009 and was later diagnosed with Tourettes. There were no new cases in 2010 and two cases in 2011. In 2012, there were at least 14 cases, 12 of whom reported the appearance of symptoms between August and November, while two others from this cohort noted that while experiencing sporadic tics prior to the outbreak, they intensified in September 2012. The affected students spanned grades 9 to 12 (9 = 4; 10 = 7; 11 = 1; 12 = 6). The tics were described as hiccups, grunts and yelps. ⁶ On 30 June 2014, the schools merged into Essex North Shore Agricultural and Technical School. At the time of the outbreaks, the student populations were just under 500 (NSTS = 475; EATS = 479). On the day the story broke, Danvers Health Director Peter Mirandi told the Salem News that it would be irresponsible to comment further, concerned that media attention could exacerbate the outbreak.

The shadow of Leroy and the public health response

The outbreak transpired in the wake of a similar cluster of vocal tics at Leroy High School in western New York between October 2011 and mid-2012, involving 18 students (17 girls, 1 boy), and a female nurse. ⁷ The case attracted national attention and was eventually diagnosed as mass psychogenic illness (MPI) by the New York State Department of Health (NYSDH). Neurologists, treating 14 patients, blamed media coverage for intensifying stress and prolonging the episode. ⁸ The intense media interest at Leroy was initially fostered by reluctance of the NYSDH to issue a public diagnosis, generating fears that they were covering up the presence of a ‘mystery illness’. ⁹ The Department released an interim report on 31 January 2012, identifying MPI as the cause, ¹⁰ triggering a second wave of media speculation questioning the diagnosis and fostering widespread conjecture as to the ‘real’ cause.

Between March and May 2013, the MDPH contacted over 2600 regional physicians and health specialists in over 50 communities where pupils attending one of the schools resided. They were asked to identify students from either school who may have recently been treated for ‘acquired vocal disorder’ involving vocal tics and chronic hiccupping. Consent to review their medical records was given by the parents of nine affected students. Based on the review, there was no common infectious, toxic, mechanical or neurological aetiology. Extensive testing was conducted of the school grounds and nearby toxic contamination sites as well as a review of pesticide applications at the sports fields of both schools. While remediated soil contaminated with fuel oil existed below the surface of Essex Aggie, it was concluded that exposure was unlikely. Air and water samples were within normal limits, as were tests for substances that could cause neurological symptoms such as mercury, carbon monoxide and volatile organic compounds. ¹¹

The Freedom of Information Act

On 20 November 2014, the MDPH issued a final report concluding that the prevalence of symptoms was within normal parameters.

Based on results of the medical records review, the crude prevalence estimate for the students with confirmed vocal tics/chronic hiccups at the schools is estimated at 1%, which appears consistent with prevalence estimates for tic disorders available in the scientific/medical literature. ¹¹

A subsequent Freedom of Information request revealed that, from the onset, those leading the investigation were aware of the Leroy case and how the media was blamed for exacerbating the episode. When the outbreak first became public on 29 January, the parent of an affected student complained to the department that ‘our parent group never wanted this to get out to the media’ to prevent ‘a media frenzy like the one in upper state New York last year’. ¹² Two weeks earlier, a memo was circulated in the MDPH which included a summary of the Leroy outbreak and the diagnosis of contagious conversion disorder. ¹³ On the same day, Mr Mirandi was contacted by a journalist inquiring about the outbreak. He told him that ‘no “confirmed” cases have been reported’ and ‘challenged the reporter on the validity of a story, which was reported by a mother who remained anonymous’. ¹⁴ Members of the parents tic group responded angrily when they learned of this exchange, noting that all of the affected girls were under the care of physicians, but their medical records had not been solicited despite the MDPH having been aware of the outbreak since early November. Mirandi defined ‘unconfirmed’ as any case ‘not reported directly by a physician or medical expert to a public health agency that is specifically poised to receive said data’. ¹⁵ One parent wrote: ‘You do not have the medical records to “confirm” these treatments as you have not requested nor provided us a method to submit them’. They questioned the ethics of his challenging the validity of the story to the media, which was viewed as deceptive and dismissive of the seriousness of the outbreak. ¹⁶ Other parents were critical of school administrators for acquiescing to the health department. One parent observed that the position of no confirmed cases was ‘setting a tone of a non-issue’ that was leaving the girls vulnerable to ridicule. They noted that their daughter and other affected girls ‘were getting hassled since the news reports from peers in the school and on Facebook, and now it appears they are receiving it from your administration as well’. ¹⁷ By adhering to this definition of an unconfirmed case but not requesting the medical records, Mr Mirandi was able to marginalise the outbreak to the media, at the cost of alienating parents.

Five days after the final report was issued, a reporter wrote to the department and noted that while otherwise exhaustive and ruling out environmental factors, their investigation ‘lacks a diagnosis, other than to conclude such tics are prevalent in students at some rate. Did the department conclude any kind of mass hysteria or psychogenic illness was at play, here?' ¹⁸ The same day, MDPH spokesman David Kibbe affirmed: ‘The DPH investigation did not observe a mass psychogenic outbreak, as the number of cases appears to be within the range of prevalence expected as normal’. ¹⁹ The next day, the Chief Medical Officer for the MDPH Bureau of Environmental Health, Dr Jonathan Burstein, circulated an internal memo to key figures in the department, summarising his medical records review. He had systematically dismissed the likelihood of an array of conditions but one: ‘mass psychogenic factors’. ²⁰ The review made no reference to crude prevalence estimates for vocal tics, and was not mandated to consider the larger context of the outbreak involving similar tics among 18 teenaged girls at the same school within a relatively short time span, and for which environmental factors had been excluded. Tic disorders are more common in children, affect boys more than girls by a ratio of about 3:1 and decrease in adolescence. ²¹ In the department’s final report, Dr Burstein’s assessment about the possible involvement of MPI was omitted. The day after the final report was issued, a policy report circulated in the MDPH which included outbreak ‘talking points’. This document included a summary of the medical records review; it too omitted any mention of MPI. ²²

Motor tics (brief, uncontrollable repetitive movements) and vocal tics (sounds) are classified as either chronic (persisting for over a year) or transient (enduring less than a year). Given that the medical records review by Dr Burstein was not completed until more than 12 months after the outbreak, and he expected the symptoms to slowly decline over the following year, most if not all patients are best described as exhibiting chronic vocal tics. The MDPH does not say how it determined their 1% crude prevalence estimate for students with confirmed cases ‘of vocal tics/chronic hiccups at the schools’. However, early in their investigation they decided to follow ‘the Ipswich model’ in reference to a 2006 cluster of motor and/or vocal tics in a small group of children in Ipswich, Massachusetts (seven boys, one girl). They observed that according to a literature review, tic severity peaks between ages 9 and 11, and that ‘just over 1% of the population could be characterised as having either a chronic motor or vocal tic disorder’. ²³ These prevalence figures appear to have been applied to the 2014 report. Where the Ipswich study noted that just over 1% of the population aged 7–15 years exhibited ‘either a chronic motor or vocal tic disorder’, the 2014 report calculated a crude prevalence estimate of 1% of students at the two Massachusetts schools for ‘vocal tics/chronic hiccups’. ¹¹ The figures on which the Ipswich study were based involved 4479 Swedish school children. It found that 1.3% exhibited either a motor or vocal tic. However, closer scrutiny of this total reveals that only 0.5% exhibited chronic vocal tics. Furthermore, of this 0.5% subset, 70% were boys, leaving the incidence of chronic vocal tics in girls at 0.15%. This figure is even lower if we consider that in the 7–15-year age group surveyed, prevalence decreases with age. While the Ipswich study conclusions accurately reflect the literature, they refer to a smaller group of predominately male children who were geographically dispersed and suffering from a tic disorder (although not all had vocal tics); they do not fit when applied to the 2012–2013 outbreak involving the sudden clustering of similar vocal tics in 18 adolescent girls attending the same school.

Discussion and recommendations

The heart of the issue is whether it is ethical for public health agencies to deal with crises by withholding information about their diagnosis. In failing to render the evident diagnosis of MPI, the MDPH may have been trying to avoid issuing a controversial diagnosis. Such strategies make it difficult to track MPI and gain insights into how episodes originate and spread. Do public health agencies have a right to keep a diagnosis from their patients, even when their patients and their families are likely to reject it – and the very act of issuing the diagnosis may temporarily inflame anxieties? The report’s final conclusions of ‘normal prevalence’ were met with scepticism even by school officials and journalists who viewed the outbreak as a mystery. ¹⁹

If we are going to lift the stigma of MPI, public health agencies need to broach the subject with transparency and diplomacy. The key to changing perceptions lies in effective communication. Simon Wessely observes:

A firm public message that certain symptoms are probably psychological in origin will probably help prevent their spread, but possibly at the cost of alienating those already affected and their families. The challenge is to convey the scientific reality without being seen as blaming or demeaning the victims. ²⁴

Public health officials should never intentionally dispense false or misleading information; patients have a right to know their diagnosis, whether they accept it or not. Nothing less than the credibility of the public health system is at stake. When diagnoses are intentionally withheld and later made public, it is likely to be met with greater scepticism than it ordinarily would have. This is what happened at Leroy. Public health authorities need to combat fear and uncertainty with factual information, compassion and understanding. The strategy employed by the MDPH may mask a wider problem; how can we effectively study a phenomenon that is being deliberately misreported or portrayed as a ‘mystery illness’ whose cause may never be known?

In responding to suspected outbreaks of conversion disorder, public health officials should consider the following additional guidelines:

During the initial stages of an outbreak, officials may legitimately consider withholding the diagnosis, if they suspect that the subsequent media attention and public backlash may exacerbate and prolong the episode. However, once the event has subsided, there is a responsibility to publicly release their diagnosis.

In raising the likelihood of MPI, care should be taken to refrain from using emotive and potentially stigmatising language (e.g. ‘hysteria’) as historically such terms have been used to marginalise girls. More neutral terms should be employed such as ‘stress reaction’ and ‘psychogenic illness.’

Avoid making statements such as ‘it’s all in their heads’ as the symptoms are real. They should remind the public that most victims appear to be normal, healthy people who are suffering from a recognised medical condition.

Officials should coordinate information that is released to the media, ideally through a single or limited number of sources or spokespersons. This is necessary to present a uniform message and reduce the potential for misinformation and public confusion.

Public health departments have the difficult task of assessing possible outbreaks of MPI, the diagnosis of which is often met with public resistance due to the stigma that is attached to the condition. It has been over half a millennium since William Griggs misdiagnosed the outbreak of mysterious symptoms at Salem as stemming from witchcraft. Yet, conversion disorder continues to pose a challenge for the victims, their parents and society but none more so than public health departments.