ILLNESS FROM TREES.

Otago Daily Times, Issue 19219, 9 July 1924, Page 4

ILLNESS FROM TREES.

AILMENTS TRANSMITTED TO HUMAN BEINGS. For centuries ir.t'ii have suspected that some at leant of their diseases come io them from animals. But that disease should reach us from plants is an entirely new idea—if the single case of “hay fever” be excepted, writes a student of medicine in the Daily Chronicle. Had not very definite proof of its correctness been forthcoming recently, we should certainly have dismissed it as ridiculous. The ’first "cine” in this mystery was obtained when Dr Lafont discovered that certain prickly plants occasionally harbour living germs known as flagellates. These arc minute specks of life possessing long and very active tails, and thus, in a way, resembling tadpoles. They lash their tails about, and so propel themselves. The next discovery was that the tailed germs were sometimes oaten by insects living on the plants, and that they remained alive in the bodies of these insects. 'That remarkable fact led at once to the.question whether some of the germs of disease may not also be "tree-dwellers.” An answer to it has recently appeared in the “Annals of the Pasteur Institute.” Dr Franchini, who supplies this answer, states that he carried out experiments on the disease known as Kalaazar, or the “black sickness,” and on one of the socalled trypanosome infections. In both cases he found that the germs in question could be “cultivated” on the prickly plant on which the tailed germs were first discovered —in short, that both these! germs are tree-dwellers. The importance of the discovery in connection with Kala-azar lies in the fact that this disease, is enormously prevalent in India, where, in past years.* it used to sweep away thousands of lives. There is strong suspicion tiiat it is carried from patient to patient by parasites. But no one has been able to explain how the parasites themselves become infected in the first instance. Again, it is known that the best way to rid a native village of this plague is to remove it bodily to a fresh locality. If Dr Franchini is right, the explanation may be that when the bushes and shrubs surrounding a village arc infected, insects will also become infected, and thus carry the infection to human beings. Some of our home ailments tend to break out at certain times of the year, and only at these times. In view of the discovery of these tree-dwelling germs, it may well bo that such outbreaks correspond to the flowering or fruiting seasons of xiarticular plants.