Parasitic Diseases

The parasites are of two kinds, animal and vegetable.

The principal animal parasites are the Acarus scabiei, or itch mite; the Pedicidus, or louse; the Cimex lectularius, or bedbug, the Pulex irritans, or flea; and the Pulex penetrans, or chigoe.

The bite of the Cimex lectularius causes hyperaemic papule with a small red spot in the centre. That of the flea produces a little circular erythematous spot, which exhibits a dark speck in the centre, that marks the wound made by the insect. The chigoe attacks the feet and hands, entering the skin beneath the nails or betwixt the toes, or upon some portion of the extremities, either by a channel made for itself, or by the ducts of the skin; its tracks can sometimes be traced as an elongated brown spot.

The application of a lotion of glycerine and water, of each 3jj, and tincture of calendula 3j will be found very useful in allaying the irritation in the case of the first two. The treatment of chigoe disease consists in dilating the original channel of entrance, and carefully removing the chigoe bodily; after which apply an ointment composed of lard and salt.



Certain caterpillars, if they get upon the skin, may excite urticaria also.

Children of lymphatic temperament who are not kept clean, are poorly nourished, or insufficiently clothed, and live in rooms badly ventilated, are particularly liable to vegetable parasitic diseases; and unless measures are adopted to remove the exciting causes and predisposing conditions treatment is unsatisfactory and relapses are frequent. The patients should be isolated whenever practicable.

The varieties are: Tinea favosa, or favus; tinea tonsurans; tinea circinata; tinea versicolor; and onychia parasitica.