title: Outbreak of Mysterious Illness Among Hospital Staff: Poisoning or Iatrogenic Reinforced Mass Psychogenic Illness?
abstract: BACKGROUND
  Hospitals are rarely reported as settings for mass psychogenic illness (MPI). The present report scrutinizes an outbreak of probable MPI among hospital staff, with medical intervention reinforcing the course of the illness.
  
  
  METHODS
  Four of seven staff members in an emergency department became acutely ill with nonspecific symptoms. After uneventful observation they were discharged, but symptoms worsened at reassembly for debriefing. Poisoning with hydrogen sulfide was suspected, and the victims were transferred by helicopter for hyperbaric oxygen (HBO) treatment. During the following 9 days, 14 possible poisoning victims were identified, 6 of whom were transferred for HBO. After hospital stays with repeated HBO treatment and examinations without identification of significant physical disease, the majority of the 10 HBO-treated victims remained symptomatic, some on prolonged sick leave. The ward was closed for several weeks during comprehensive but negative investigations for toxic chemicals. Clinical data and lack of indication of chemical exposure, together with an attack pattern with only some individuals becoming ill in a shared environment, suggest MPI. Iatrogenic influence from dramatic intervention was probably a strong driving force in the outbreak. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Awareness of MPI may prevent unnecessary and potentially harmful treatment as well as improve health care resilience, particularly with respect to preparedness. Outbreaks of illness in a group of symptomatic victims without indication of significant physical disease should be managed by observation and limited intervention.
authors.affiliation: Department of Occupational and Environmental Medicine and Danish Poison Information Centre, University of Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Jacobsen
authors.affiliation: Department of Occupational and Environmental Medicine and Danish Poison Information Centre, University of Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.
authors.forename: Niels Erik
authors.initials: NE
authors.lastname: Ebbehøj
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis / Q000506:poisoning; D003937:Diagnosis, Differential; D004196:Disease Outbreaks; D004636:Emergency Service, Hospital; D006760:Hospitalization; D006801:Humans; D006862:Hydrogen Sulfide / Q000506:poisoning; D006931:Hyperbaric Oxygenation; D009325:Nausea / Q000523:psychology*; D010564:Personnel, Hospital / Q000523:psychology*; D011041:Poisoning / Q000175:diagnosis; D011602:Psychophysiologic Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D012054:Reinforcement, Psychology; D014717:Vertigo / Q000523:psychology*
chemical_list: D000395:Air Pollutants, Occupational; D006862:Hydrogen Sulfide
keywords: anxiety; health care resilience; iatrogenic; mass psychogenic illness