1696 



TROPICAL POISONINGS 



tioned the ackee, without, however, being definite as to its causal 

 effect. 



In 19 12 Potter, after considering cerebro-spinal meningitis, 

 ptomaine poisoning, ackee poisoning, and cassava poisoning, came 

 to the conclusion that it was a phase of yellow fever. 



In 19 13 Scott suggested that it might be fulminating cerebro- 

 spinal meningitis, and in the same year Seidelin opposed the yellow 

 fever and the meningitis views and beheved it to be a local 

 disease. 



In 1915 Scott, as a result of an investigation into an outbreak at 

 Mont ego Bay, found that in the majority of cases ackees formed part 

 of the last meal taken in health, and that they could not be excluded 

 in a single case. Persons taking soup or pot-water made with 

 ackees developed symptoms in two hours, and death nearly always 

 resulted. 



The ackee is the fruit or aril of Blighia sapida Koenig, belonging 

 to the natural order Sapindacese, and, being a native of West Africa, 

 is merely an introduced plant in Jamaica. 



Only unsound ackees cause the symptoms, and an ackee is un- 

 sound (i) when it is unopened; (2) when it is picked from a decayed, 

 bruised, or broken branch; (3) when it has been forced open; 

 (4) when it has a soft spot. 



In 19 17 Scott confirmed this view as to the causal effect of the 

 ackee, and by his experiments upon animals demonstrated the nature 

 of vomiting sickness. 



Climatology. — So far the disease is only known in Jamaica, but 

 it must be remembered that the tree is a native of West Africa. 

 We, however, do not know whether the fruit is used as a food in 

 this country, and, at all events, up to the present no one has reported 

 the poisoning from that part of the world. 



etiology. — Vomiting sickness is caused by eating the unsound 

 fruit of Blighia sapida Koenig, the ackee plant, or taking the soup 

 or ' pot -water ' made with this fruit. These latter are the more 

 severe cases, because the poison appears to be extracted by boiling 

 with water. Alcoholic extract of unsound ackees is not poisonous. 

 The watery extract^ on the other hand, when administered to cats 

 and dogs,produced the same symptoms and mortality rate as in man, 

 and after death the same post-mortem signs were found. Herbi- 

 vorous animals are unaffected. The poisoning takes place in the 

 months from November to April, which corresponds with the 

 ackee season. Several members of a family are taken ill at one and 

 the same time, as would be expected from a food poisoning. It also 

 occurs among near neighbours in the settlement, and is rare in white 

 children and East Indians, being confined to the children of the 

 indigenous population. There is no indication that sex plays any 

 part in the ajtiology, which must be looked upon as an acute poison- 

 ing. A case of known ackee poisoning occurring in man showed the 

 same symptoms, cause, and post-mortem changes as cases of 

 vomiting sickness, and as the experimental animals. 



