On Monday October 2, 2023, news reports from western Kenya told of a bizarre condition that had swept through St Theresa’s Eregi Girls’ High School. At least 62 students were hospitalized after exhibiting uncontrollable twitching of their arms and legs, including rhythmic muscle contractions and spasms.1 At times the girls were reported to appear as if possessed by spirits and complained of headaches, dizziness, and knee pain. Many were unable to walk and had to be taken in wheelchairs to waiting ambulances. The strange outbreak occurred in the town of Musoli, about 230 miles northwest of Nairobi. When school opened the next day parents stormed the campus demanding that it be closed until more was known about the outbreak.2 By Wednesday, education officials shut down most of the school as the number of students taken to hospital reached 106.3
International media coverage of the outbreak was often ominous. The Hindustan Times reported: “Mystery Illness in Kenya Leaves School Children with Paralyzed Legs.”4 The Indo-Asian News Service proclaimed: “Mysterious Disease Paralyzes 95 Girls in Kenya.” The Latin American CE Noticias Financieras news agency carried the apocryphal headline: “Nearly 100 Students Walk like ‘Zombies’ in Kenya, Mysterious Illness Raises Alarm Bells.”5
Many people took to social media to blame the COVID-19 vaccine, which was given to the school’s students in July of last year. Others suggested that the girls were faking. Samples of blood, urine, phlegm, and stool were taken, along with throat swabs. All proved to be unremarkable. By Thursday, Kenyan health officials also ruled out the role of infectious disease and instead concluded that they were suffering from “hysteria” in response to stress from upcoming exams.6 The reaction to this episode highlights several misconceptions about outbreaks of “mass hysteria.” As someone who has studied this topic for over three decades, allow me to make some observations.