The Great War was the first major conflict where the death rate due to the trauma of war (largely inflicted by projectiles such as bullets and shells) was greater than that due to disease; on the Western Front the ratio was 5:1. But no soldier on the Western Front could ever be entirely free from the threat of war diseases in their many guises. However, paradoxically, it is also probable that it was the first major war where the conditions created by the fighting actually reduced the amount of a disease to less than that which would normally be expected in a theatre of war. A classic case in point being the plague of many wars - even on the continent of Europe - malaria. The extensive use of poison gases, and the products of high explosives, in the battle zone, polluted the air and ground to such an extent that the vectors of the disease (Anopheline mosquitoes) were unable to live long enough to transmit malaria. Less than 1,000 cases of malaria were recorded on the Western Front, with deaths only in the low teens. Of course, there were very degraded living conditions in the trenches of the British Expeditionary Force (BEF) with the resultant deplorable state of hygiene, both personal and environmental, imposed on the hapless trench dwellers of all sides. This meant that the incidence of most diseases soared to often chronic (constant) and epidemic (widespread) proportions, with significant implications for the health of the affected troops and their effectiveness on the battlefield.

The progressive industrialisation of the Great War greatly enhanced the rate of technological advance in many spheres, be it aviation, munitions, weapons and even medicine; including diagnosis and treatment. A good example of the latter was the widespread introduction of voluntary vaccination against some of the world's most prevalent and deadly diseases. Unfortunately, the uptake of these vaccinations in 1914 was initially entirely voluntary in the British Army, thus diminishing its effect to far less than the optimum achieved when compulsion was eventually more widely employed in the British Army after 1915.

Sadly, the appearance of antibiotics, which transformed the success of the cure-rate of previously intractable bacterial diseases in the later part of the Second World War, did not materialise during the Great War and the only available treatment was often the relatively ineffective medications of past ages (eg Sphagnum moss dressings, potassium permanganate, boric acid, etc).

Similarly, the efficacy of the well-proven medicines and practices that were available were not often fully appreciated nor always properly deployed by the British Army. Again, malaria provides an excellent case in point. The Germans, in their East African Campaign, rigorously employed a malaria prophylaxis (prevention) campaign for non-immune European troops using the drug quinine, which they uniquely cultivated in East Africa. This enabled them to keep these key expatriate personnel in the field and wreak many effective military tactical and operational defeats on the less well protected European and Asian troops of the British Army in East Africa.

Significant factors in the prevalence of disease on the Western Front 

The majority of the troops of the BEF arriving on the Western Front had led a very simple lifestyle until the outbreak of war. They were accustomed to the basic, but often quite effective, hygiene practices they had practised as a norm of daily life, and these practices provided some basic protection against disease. Nevertheless, almost all had had suffered the usual diseases associated with childhood and early adult life in the UK and, inevitably, they had acquired a whole range of specific antibodies to resist future infections from this normal range of lifetime diseases.

But, when these soldiers arrived with the BEF on the Western Front, they were thrust into a highly concentrated world of closely packed soldiery from many countries who were carriers of strains of diseases beyond the experience of the newcomers' own antibodies. In addition, they were in contact with huge numbers of animals (principally animals of burden such as horses), which carried their own range of diseases, as well as hordes of infested vermin (eg rats) and, perhaps, the most detested and distressing of all, heavy infestations of human body parasites such as lice.

Epidemic typhus/Trench Fever

Lice are the long-feared vectors of epidemic typhus. This disease is caused by an organism - of the genus Rickettsia - which demonstrates characteristics of both bacteria and viruses, that is like viruses it only grows in living cells. The infection produces severe fevers, painful aching joints and body rashes. These often led to a fatal involvement of the kidneys and other major organs of the body.

Exceptionally, the French Army on the Western Front suffered severely from epidemic typhus, and well over 100,000 cases were recorded with a 10% fatality rate. But the French Army was particularly notorious for its poor field hygiene. The BEF, on the other hand, only had a couple of hundred of deaths from this disease despite the non-availability of a vaccine. Presumably, the reportedly better field hygiene of the British Army made a vital difference.

The means by which epidemic typhus was transmitted from louse to man was that the feeding lice left their infected faeces on their victims' skin and the soldier's scratching of the open lice bites drove the infective faeces into their own flesh.

A related bacterium also caused a lesser, but long lasting, painful and debilitating disease (mainly associated with the military populations of both World War I and II). It was commonly known on the Western Front as Trench Fever or PUO (Pyrexia [ie fever] of Unknown Origin), of which 200,000 cases were recorded by the Allies on the Western Front. The author's father's Medical Service Records detail his hospitalisation for 40 days with PUO whilst participating as an infantryman in the First Battle of the Somme in 1916, thus indicating how such long duration diseases could have a serious effect on military operations.

In any event, the plague of biting body lice which infested the clothing of the BEF soldiers of all ranks in the trenches, without distinction, and the intense itching caused by their bites, caused immeasurable discomfort and stress even without the presence of these concomitant infections.

Diseases associated with climatic conditions and the hazards of war

Additionally, the BEF on the Western Front faced, largely unprotected, full exposure to the whole gamut of the continental type climatic conditions. This exposure caused injuries that facilitated several incapacitating diseases, for example Trench Foot (more about which later). And, looming over all, there was the major, constant, physical and psychological hazard of a determined enemy using all its military might and understanding of the machinery of war, and new technology, to wreak ruin on the BEF and wrest it from its fragile troglodyte life in the trenches and hurl it back across the English Channel. No measure was too gross to be used by the Axis against the BEF to create man-made pseudo-diseases - such as the damage to mucous membranes caused by toxic gas - and there was no hesitation on the part of the German High Command to inflict it in the most energetic and efficacious manner: the effects of these German transgressions were intentionally highly grievous.

Accordingly, the German occupation of France and Belgium was strictly founded on the establishment and maintenance of the strongest and sturdiest of defences, sited in the most favourable defensive positions; the German trench systems were commonly 4-5,000 yards deep. All backed by a fierce determination to maintain these defences in the best of condition, with the highest levels of comfort and protection for its troops of occupation, whilst forcing the BEF to operate in the most insalubrious of territory (with defences commonly only 1,000 yards deep) in order to achieve the British aim of a constant offensive stance.

The rationale of the commanders of the BEF was that defences should be of the most temporary nature possible commensurate with the need to expel the German Army from the occupied areas of France and Belgium and push them back to within the borders of Germany with the utmost despatch; ‘Home (to Britain) by Christmas' was the slogan of the BEF. The last thing the British War Office wanted was a BEF comfortably settled behind secure defences in France and Belgium; ‘Onward ever onward' was the jingoism of the Western Front. Unfortunately, as indicated earlier, all this often had the long term effect of putting the BEF in an inferior situation. The lie of the land, the effects of climate (water logging) and the physical protection of the soldier (the German dug-outs on the Somme were up to 30 feet deep) were usually worse for the BEF when compared with the definitely better sited and constructed defences of the German Army. Indeed, if the creation of a perfect German defence system at a particular location required the total destruction of the local French or Belgian civil infrastructure, so be it! In British eyes such deliberate ransacking of civilian areas for usable materials and resources was to be avoided wherever possible.

This lack of an equivalent intensive preparedness by the British would impose on the BEF additional victims of a whole series of horribly debilitating diseases largely brought on by the adverse climatic conditions and the poor environment to which the soldiers of the BEF were almost routinely exposed.

Diseases of particular tactical and operational importance to the BEF on the Western Front

The most common diseases affecting the BEF on the Western Front may be placed in the following groups: those affecting digestive system of which the various forms of diarrhoea and vomiting were dominant; chest infections, particularly bronchitis and pneumonia; and skin infections of which scabies (caused by skin tunnelling mites) was surely one of the most debilitating. All of these diseases could be associated with the generally poor hygienic conditions in the trenches and the general lack of the ability of the trench-bound soldiers to maintain their own satisfactory levels of personal hygiene, cleanliness, comfort and even nutrition.

Of course, many of the diseases that were prevalent to a greater or lesser extent formed complexes of disease that were often difficult to diagnose and treat. A particular example was the confusion of cardiac problems and shell shock; for many months in the early part of the Great War, at least in the British officer cadre, shell shock went under the diagnosis ‘Disordered Action of the Heart'. This confusion seriously retarded the proper diagnosis of shell shock and delayed the deployment of effective treatment regimes.

Diseases that require a particular mention because of their operational importance are:

Trench foot (Immersion Foot)

This was a non-contagious condition that arose from the prolonged immersion of the feet/legs in cold water whilst serving in the trenches. The feet, in effect, became water-logged and chilled. The blood circulation was adversely affected - badly fitting boots and tightly bound puttees also aggravated the problem - and the feet/legs became infected and began to mortify. The most serious cases led to gas gangrene with amputation(s) required to preserve the life of the soldier. Overall, 75,000 of the BEF were hospitalised with this condition. But the total number of cases was definitely much higher as in some units it was made a punishable offence to contract the condition. However, harsh as this may seem, its ruthless application did at least ensure a higher rate of compliance with the limited remedial measures that were available, for example, a liberal application of whale oil. Also, frostbite was a common complication. In some BEF battalions on the Somme in 1916-17, about half the men were operationally compromised by these twin conditions of exposure. Overall, on the Western Front there were around 90,000 British hospital admissions due to trench foot and frost bite either alone, or in combination.


From 1915 onwards, a new strain of influenza began to appear in all of the combatant armies on the Western Front. Incorrectly designated as Spanish Flu, its genesis probably lay in the mutation of avian type influenza from Asia which jumped the species via pigs to arrive in the crowded military base camps of the USA and Europe. In the late summer of 1918, a particularly virulent form of influenza was occurring in epidemic form amongst all the troops of all the combatant armies on the Western Front and their base camps. The local indigenous civilian populations were also badly affected.

By the time the influenza epidemic had lost its virulence in the early 1920s, it had wreaked a global death toll of as many as 50 million - some sources postulate even 100 million (6% of the then global population) - vastly outnumbering all of the other casualties of the Great War. The primary cause of its high death rate was not the influenza virus itself, dramatic though that was, but rather the associated pneumonia that struck many of its victims after the influenza virus had peaked. It killed many of its victims in a matter of a few hours. However, many of these pneumonia deaths were recorded as due to the ‘Spanish Flu', thus diminishing the true impact of pneumonia.

Also, of importance to military operations on the Western Front was the fact that the principal victims of the influenza were not, as usual, the very young and very old, but rather the age group 18 - 30 years, ie that of the majority of the soldiers on the Western Front.

Venereal diseases 

The dichotomy of the social mores regarding sex of Edwardian society - prostitution was rife, especially in the big cities - meant that a considerable number of the soldiers who fought with the BEF were already infected with one or more of the more common venereal diseases - both gonorrhoea and syphilis being dominant - when the troops were transported across the English Channel to the Western Front.

Once deployed in the active battle zones on the Western Front, the BEF soldiers found themselves in a vast masculine encampment almost devoid of social contact with any females at all; deprivation which even applied to the French and Belgian soldiers in their home countries. As is norm in such situations, the male desire for sex, particularly in times of severe stress with the consequential loss of inhibitions, was met by needy, or greedy, women who were from the area, or attracted to it, and who became sex workers of various kinds. Inevitably, they became the focus of the transmission of venereal diseases and many BEF soldiers were infected thus: at least initially, the use of condoms was rare. Figures vary vastly, but official documentation states that around 4% of the strength of the BEF was infected at any one time. But the rate was much higher in the various contingents of Commonwealth troops, being overall nearly double the British rates, and in some individual units five times greater (quite probably, the considerably higher pay of the Canadian and ANZAC troops was a factor here).

Overall, there were 400,000 cases of VD recorded in the British Army in the Great War, with around 150,000 hospital admissions on the Western Front equal to an annual rate of between 15 - 20% of all hospital admissions. But this included infections contracted outside the battlezone - whilst on leave, etc. These rates of VD are equivalent to about double that of any other group of diseases. Also included in this figure are the about 1% of soldiers who, it is said, deliberately sought infection with the motivation of escaping the fighting; at least temporarily. In the absence of antibiotics, treatment for these two VDs was both painful and quite dangerous. Paradoxically, the potentially more serious infection of syphilis was more responsive to treatment (with Salvasan - a toxic arsenical compound) than gonorrhoea which was usually treated with the potentially very toxic drug mercury, or the rather less dangerous silver nitrate. The commanders of the BEF on the Western Front took an ambiguous attitude to sex, varying from banning the fraternisation of soldiers with sex workers to turning a blind eye to houses of ill repute, or putting civilian areas out-of-bounds to all but the patrols of the Military Police. Particularly, the Belgian Army on the Western Front was highly prohibitive about such casual sex by its soldiers.

However, whilst it is known that brothels were established in the environs of some BEF base camps, is most unlikely that prostitutes (and any other ‘camp followers') were allowed into the BEF's reserve lines and the trenches of the battle zone, as was the case in many former wars.


The Great War was the third war of the Industrialised Age: the American Civil War (620,000 died) and the Russo-Japanese War (165,000 casualties) preceded it by 53 and 10 years respectively.

Both of these earlier wars gave a clear indication of the large numbers of casualties that could occur from the industrialised mass production of the munitions of war, and evidenced the possibility that future wars would be more static and involve trench warfare. However, the slaughter and grinding misery of the trenches in the Great War vastly exceeded the most pessimistic of possible scenarios. The way that major elements of several battalions of infantrymen could be simultaneously liquidated in a matter of minutes was quite unprecedented. As the Great War progressed, the toll of the diseases of war, old and new, was better contained and treated with generally reduced death rates: nearly 80% of the BEF casualties returned to their duties with the army after treatment, although by no means all of them were fit enough for redeployment for frontline duties on the Western Front.

Although there were 516 female nurses with the BEF in France in August 1914, rising to 6,394 at the Armistice, no specific breakdown of casualties in this group appear in the published official post-war medical statistics.

But, despite all the casualties from trauma and disease, and the general misery that was inflicted on the BEF by the enemy and the climate, the final phase of knockout battles (the Hundred Days) of the Great War was led by a force that was at the outbreak of the war generally acknowledged as the weakest army. This force was the BEF, but a BEF vastly expanded in its strength of men and equipment, much experienced in the art of industrialised warfare, and undefeated by even the newest and direst diseases of war.

Article contributed by Dr David Payne 

[This article was first posted on a previous version of The Western Front Association website: 22 February 2012]

References/Further Reading

For the specialist:

MacPherson, Major-General W.G. History of the Great War: Medical Services, - Vols 2 (Western Front: France and Belgium, 1914, 1915) and 3 (Western Front 1916, 1917 and 1918; Italy; Egypt and Palestine). The Naval and Military Press, London, UK. (Not dated - original 1923).

Mitchell, Major T. J. and Smith, G. M. Official History of the Great War: Medical Services, Casualties and Medical Statistics. The Imperial War Museum, London, UK/the Battery Press Inc. Nashville, Tennessee, USA. 1997.

For the general reader:

Bergen, L. van. Before My Helpless Sight. Ashgate Publishing Ltd, Farnham, Surrey, UK. 2009.

Bridger, G. The Great War Handbook. Pen & Sword Books Ltd, Barnsley, South Yorkshire, UK. 2009.