in more insanitary towns and villages on the coast. Certain ships are notoriously foci of the disease, and, I believe, can carry the infection. Some time ago I saw a medical man suffering from a chronic fever, whose blood, in expert hands, gave the characteristic reaction, and who, if he had undulant fever, certainly got it from a ship which had recently been to the Mediterranean. He himself had never been in that part of the world, and had not been out of England for a year.
Influence of social conditions.— All classes are liable to this disease; the officer and his family as well as the soldier in barracks or the sailor on shipboard.
Mode of infection.— Although the possibility must not be ignored, undulant fever is not generally transmitted directly from one person to another; that is to say, is not usually directly communicable from the sick to the healthy. Seeing that the germ may abound and persist in vaginal mucus for a very long time, Lafont suggests that the infection may be acquired during coitus. The germ is readily conveyed by inoculation the prick of a contaminated needle will suffice. Zammit and others seek to incriminate the mosquito as an inoculator, and point, in support of their contention, to the special prevalence of the disease in the mosquito season, to the facts that of 896 mosquitoes examined bacteriologically it was found in 4, and that the disease has twice been conveyed to monkeys by infected insects.
A very striking circumstance is that in some hospitals the nurses and attendants in the fever wards are ten times more liable to contract the disease than people not so employed.
Possibly the infection is blown about by winds as dust, and being inhaled, or falling into the conjunctival sac, or on a wound or sore, obtains an entrance. Bearing in mind the presence of the germ in the excreta of man and animals, the dusty character of the soil of Malta and many Mediterranean towns, the extremely minute dose of a culture required for a successful inoculation, in any or all of these ways infection seems possible. I have seen a case, originating in England, in which a father was apparently
