contagious laughter

rltz |  The mode of spread of this disease would seem to be from person to person. In most instances it was possible to trace recent contact with someone exhibiting the same symptoms. This might suggest a virus disease spread by droplet infection. The results of the laboratory examination, the lack of abnormal signs on the physical examination and the fact that the majority of the patients had more than one attack of the disease are against an infectious aetiology.

Contamination of food by toxic substances is possible explanation. Seeds of Datura Stramonium contaminating wheat and maize flour have been responsible for epidemics of food poisoning in East Africa (Anderson et al, 1944; Raymond 1944). This disease begins soon after eating posho made from the flour contaminated with the seeds and bears a superficial resemblance to the present syndrome. However, the dry mouth, fixed and dilated pupils and the muscular inco-ordination found in datura poisoning were not seen in Bukoba. Also symptoms only last a few hours as opposed to the average of seven days with the illness under discussion. No food factor which was peculiar to the people attacked has been found. No foreign seeds were found in the maize samples taken. A toxic food factor could not explain the spread of the disease from one person to another.

The third possibility of mass hysteria seems the most likely explanation. We are at a loss to explain why the disease first started. Close questioning f the girls involved has failed to produce any reasons for the initial attack. Once started, this mass hysteria could spread without the original precipitating factors being present.

The middle ages in Europe produced several epidemics of mass hysteria, of which the dancing manias of Germany and Italy are the best known (Major, 1954.) These followed on the Black Death and are assumed to be a product of the dislocation of normal life caused by the plague.

Hecker (1844) describes the following example of how the tendency to sympathy and imitation increases under excitement: “In a Lancashire cotton shop in 1787 a woman worker put a mouse down the neck of a companion who had a dread of mice; the fit which she immediately threw continued with violent convulsions for 24 hours. On the next day three other women had fits and by the fourth no less than 24 people had been affected; among these was a male factory worker so exhausted by restraining the hysterical women that he had caught the illness himself. The disease spread to neighbouring factories because of the fear aroused by a theory that the illness was due to some sort of cotton poisoning.”

In Tanganyika, in the village of Kanyangereka, where most of one family were attacked, a man of 52 years of age living nearby saw these people during their attacks. He was very upset at the sight of their suffering, and soon after returning to his hut, where he lived along, he felt something telling him to laugh and cry and shout. This he continued to do for most of the night.

The type of mental disorder that affects a community is influenced by the culture of this particular community. Examples of this are Amok and Latah in Malaya, Koro in China and Arctic Hysteria in Siberia (Leighton and Hughes, 1961). These authors describe a religious revival in Kentucky, U.S.A. in 1800 where the population became so fearful of their future after death that many began to exhibit jerky movements and to fall down in an apparent state of unconsciousness. Others took to barking like dogs, and this spread from person to person.

This epidemic in Tanganyika of laughing and crying requires further study. In order to interpret this behavior as normal or pathological, a study of the culture context should be made. The Kentucky outbreak followed a pattern similar to the emotional release of the New England revival a few years before. We can find no written or verbal record of this present epidemic having occurred in the Bukoba district previously.

SUMMARYAn epidemic of laughing, crying and restlessness in the Bukoba district of Northern Tanganyika is described. The disease commenced in a girls’ school and has since spread to other schools and to villages in the area. No significant abnormal physical signs were found and all laboratory tests were normal. There have been no fatalities. No toxic factor in the food supply was found. It is suggested that this is mass hysteria in a susceptible population. This is probably a culturally determined disease.