in time, though never to the horrors of a heavy bombardment, but sooner or later the exhaustion of active service often resulted in a gradual failure of the adaptation, so that not only the constitu- tionally timid the martial misfits but also some who had faced the life cheerfully for months or years broke down from the long- continued emotional strain.
The emotion of fear acted in three ways. In the martial misfit, who is by nature very suggestible, it gave rise at once to such physical symptoms as tremor, inability to speak and inability to move, which might be perpetuated by auto-suggestion as hysterical tremor, mutism and paralysis, the three together constituting one form of the condition often called shell-shock, though it rarely had anything to do with actual shell concussion. In other cases it resulted in a man passing into a dazed condition or stupor, which might lead him to wander from his post of duty and run risk of being court-martialled as a deserter. Finally, it might result in such a disturbance of the suprarenal and thyroid glands that a condition of continuous over-activity, with symptoms not unlike those of Graves's diseases (exophthalmic goitre), might follow.
The acute emotion caused by a single exceptionally terrifying experience sometimes led to such a change in an individual that he became for a time extremely liable to develop hysterical symptoms by suggestion, especially if the experience led to actual physical results. Thus, when a man was gassed he became temporarily unable to see or to speak owing to irritation of his eyes and his larynx, and he often vomited owing to irritation of his stomach. Any of these symptoms might be perpetuated by suggestion hysterical blindness, inability to make any sound at all or more commonly inability to speak above a whisper, and vomiting being the respective sequels. If a man was blown up or buried, the loss of memory, headache, paralysis, deafness and convulsions which might result from the concussion of his brain were often perpetuated as hysterical symp- toms long after the actual changes in the nervous system had so greatly diminished that the symptoms should have completely disappeared. After much study of the problems presented by these hysterical symptoms, which became increasingly frequent as the war progressed, psychotherapeutic methods, consisting of explana- tion, followed by persuasion and reeducation, were devised, which resulted in extraordinarily rapid recovery, the majority of cases, even after the symptoms had persisted for many months, being cured at a single sitting.
An exhausted officer, who was constitutionally unsuited to the life of a soldier, was more likely to develop psychasthenic symptoms than his men owing to his greater responsibility. He found it increas- ingly difficult to decide between two possible lines of action, and, when at last he had adopted one, he was full of doubt as to whether he had decided rightly. His power of concentration became deficient owing to his mental energy being largely taken up, without his fully realizing it, in repressing painful thoughts and conflicts, which he kept in the background of his mind in order to avoid distress. He consequently showed want of confidence in his actions, and became terrified that he would be unable to perform his duties in an emer- gency. His sense of duty urged him to carry on, but this was in acute conflict with his instinct of self-preservation, which urged him to get away from his hateful surroundings. In the daytime he might become suddenly overwhelmed with apparently causeless dread or terror, and he often found it difficult to fall asleep at night owing to the need of active thought to keep his distressing memories and conflicts buried. When at last he fell asleep and the controlling influence over his thoughts was relaxed, they came into conscious- ness in a distorted form as nightmares, with the result that he would wake in a condition of terror. The disturbed nights increased his exhaustion, until it was no longer possible for him to carry on with his duties. In early cases improvement rapidly followed a change to more favourable surroundings, especially if, instead of receiving the old-fashioned advice to forget his worries and occupy his mind with more pleasant matters, which it was totally impossible for him to do, he fell into the hands of an understanding medical officer, who,, after gaining his confidence, helped him to solve his difficulties by freely discussing the thoughts he had been attempting to repress, however painful they might be. It was remarkable how rapidly persistent war nightmares, long-standing phobias and obsessions, and hitherto inexplicable emotional crises disappeared directly the patient under- stood the mental processes which had given rise to them.
(B.) Infective Diseases: (a) Typhoid and Paratyphoid. In the South African War of 1899-1902, 60,000 cases of typhoid fever with 8,227 deaths occurred in the British army. In the far larger British army in France and Flanders only 4,571 cases of typhoid and paratyphoid fever occurred between Aug. 1914 and Nov. 1916, and the incidence of these diseases steadily diminished after the first few months of the war in spite of the steadily increasing size of the armies. This was almost entirely due to,the remarkable success of the prophylactic inoculation with typhoid and, later on, with mixed typhoid and paratyphoid vaccines.
Paratyphoid fever was throughout much more common than typhoid fever both in France and in the East. There were probably 6,000 cases of paratyphoid fever among the 300,000 troops who were at Gallipoli, but the disease was comparatively rare in all other theatres of the war owing to more thorough protective inoculation after the end of 1915. The mortality in France was only 1-3%; in
Gallipoli and Mesopotamia it was higher, but much below that of typhoid fever in the South African War.
(b) Cerebro-spinal Fever. -An outbreak of cerebro-spinal fever occurred among the Canadian troops on Salisbury Plain in 1915. A wide-spread and very fatal epidemic followed in many home- camps, and shortly afterwards the disease appeared in France. By the end of the year a number of cases developed on the eastern fronts. Investigation showed that the disease was caused by differ- ent types of the same bacteria, and when sera were introduced which were specific for each of these types, the very high initial mortality was greatly reduced, particularly when the disease was diagnosed early and serum given without delay.
(c) Trench Fever. In the early summer of 1915 a form of fever was observed in the British army in France, in which two or more periods of raised temperature were separated by normal intervals of a few days. Similar cases were recognized with increasing fre- quency, and the disease soon became widely known as trench fever. Thousands of cases occurred in France and Flanders between April and Oct. 1915 ; it was comparatively rare in the winter, but increased again each spring. Trench fever did not occur in Gallipoli, but was introduced into Salonika by troops arriving from France in Dec. 1915. It was first recognized in the French army in May 1916 and in the Italian army in Oct. 1917, and it was common both in Germany and Austria from 1916 until the end of the war. The characteristic fever and painful shins of trench fever appear to con- stitute a disease which had never before been described, but it is conceivably identical with a disease mentioned by Hippocrates, Galen and Avicenna, in which relapses occurred at five-day intervals. The organism which causes trench fever was never isolated, but it was
E roved that the disease was spread solely by means of lice, which had
- d on the blood of patients suffering from the disease and had then
bitten other men. The frequency of trench fever thus varied with the prevalence of lice, and if they could be exterminated in an army, the disease would disappear as surely as the lice-borne typhus fever disappeared from the Serbian army when it was freed from lice in 1915. The disease had nothing to do with the trenches beyond the tendency for men to become lousy when herded closely together. It appears to have died out completely since the Armistice. Trench fever was never fatal, but it caused an enormous amount of sickness; it was indeed the only infection which gained any hold on the British army in France and Flanders, except for the wide-spread and very fatal influenza epidemic in the summer of 1918.
(d) Dysentery. Amoebic dysentery, though common in tropical and sub-tropical countries, had never occurred in epidemic form in Europe until the summer of 1915. when nearly every soldier in the British army at Gallipoli suffered from it, and a large proportion of the thousand sick men who were daily removed from the penin- sula during Aug. and Sept. had amoebic dysentery. It was less common in Oct., and the cold and rain in the great gale at the end of Nov. were quickly followed by the disappearance of the epidemic. But no sooner had amoebic dysentery abated than bacillary dysen- tery became increasingly frequent. Amoebic dysentery was prob- ably conveyed to Gallipoli by troops coming from Egypt, where 13 % of healthy natives harbour the amoeba of dysentery in their intes- tines and where large numbers of cases occurred among British soldiers. Amoebic dysentery was also very common in the army in Mesopotamia. A few cases occurred in France after the autumn of 1915 owing to the arrival from India, Morocco and Senegal, and later from Gallipoli, of men infested with the amoeba, though not actually suffering from dysentery. The disease was spread mainly by flies which swarmed in enormous numbers wherever there was any food and in every latrine. As flies always defecate each time they feed, amoebic cysts are deposited on jam and any other human food upon which they settle within twenty-four hours of feeding on the stools of dysenteric patients. During the hottest months in Mesopotamia flies were uncommon and dysentery very rare; when flies were present in enormous numbers in the spring and autumn dysen- tery became epidemic. As soon as it became recognized that the predominant form of dysentery on the Gallipoli peninsula was amoebic and men were treated with emetine from the moment of onset, the symptoms rapidly disappeared, but reinfection was com- mon. It was the universal sickness caused by dysentery rather than the occasional death that mattered at Gallipoli, and it can be truly said that dysentery was one of the deciding factors in the failure of the campaign. Cases of inflammation and abscess of the liver due to the amoeba of dysentery continued to occur even three and four years after infection in men who had not been adequately treated.
The dysentery which has been common in armies on active service since the Peloponnesian War has probably always been of the bacillary variety. Out of 30,000 British troops who fought in the Crimea, 7,883 suffered from dysentery, and of these 2,143 died ; in the South African War there were 38,103 cases with 1,342 deaths. Bacillary dysentery made its first appearance in the early weeks of the World War in East Prussia and Galicia and was brought to France by von Kluck's ill-fed and tired soldiers on their march on Paris. It was present on every front whenever the weather was hot, and caused, an enormous amount of illness in Salonika, Mesopotamia and Palestine as well as in Gallipoli. The disease was spread by flies in the same way as amoebic dysentery.
The chief means of combating both forms of dysentery is to
