A former soldier is suing the Ministry of Defence after contracting Q fever in Afghanistan.
Wayne Bass claims his life has been ruined by the Army's failure to provide antibiotics which would have protected him from the disease.
His case is the first to test the MoD's duty to protect against Q fever, an infectious disease linked to exposure to animal excrement.
The MoD says it is not appropriate to comment on ongoing legal cases.
In 2011, Mr Bass, then a private serving with 2nd Battalion The Mercian Regiment, was deployed to Helmand Province, to an area known for its heavy Taliban presence and fire.
Pte Bass's platoon was responsible for reconnaissance and protecting other forces.
It is there that he believes he contracted Q fever, an infection caused by bacteria most commonly found in cattle, sheep, and goats.
Humans typically get Q fever when they breathe in dust from faeces of infected animals.
"To avoid enemy fire I was constantly having to dive into ditches on the ground where farm animals had been, there were animals all over the place," he says.
Initially, as is typical with the disease, he experienced flu-like symptoms and an army doctor diagnosed Q fever.
Intravenous antibiotics failed to cure him and following periods in hospital and at the MoD's Headley Court rehabilitation centre in Surrey, he was diagnosed with Q fever chronic fatigue syndrome.
Normally, the fever is successfully treated with antibiotics and it is rare for it to develop into chronic fatigue syndrome.
"On some days I'm OK, I can walk a few hundred metres but often I get breathless, have aches and pains all over my body for which I have to take very powerful painkillers.
"The nerve pain in my lower back and legs means that my back can lock up and I'm immobile.
"On a less bad day it can take 45 minutes to walk 600m," he says.
His condition means he is unable to work, but the effects are not only physical: "It has brought about a spike in my post-traumatic stress disorder, I have night terrors, I feel very low and isolated, very depressed. I am on anti-depressants. I can't see a future," he says.
Justin Glenister, a partner at Hilary Meredith, the law firm acting for Mr Bass, believes the case breaks new legal ground.
"This is the first case in which the question will be asked whether the MoD had a duty to protect soldiers against this known risk of Q fever, which we say was a preventable risk, and what steps it ought to have taken to protect them. There are other similar cases being prepared."
The MoD's defence, seen by the BBC, says 200 personnel per year tested positive for Q fever in 2008-2011 and of those only a third were symptomatic.
The MoD says the risk of contracting Q fever is very low and it follows the recommendations of the Joint Committee on Vaccination and Immunisation which does not recommend vaccination for Q Fever.
Q-Vax, a vaccine against Q fever, is not licensed in the UK.
Mr Bass's case is that the Army failed to provide the antibiotic doxycycline to guard against the risk of Q fever.
But the MoD says it would not have been reasonable to use doxycycline due to its side-effects and because it would have compromised the effect of anti-malarial drugs given to troops.
It denies that any action could have been taken to avoid him contracting Q fever.
Simon Clarke, associate professor in cellular microbiology at Reading University, says: "Doxycycline is an anti-malarial. If given it could have protected against both malaria and Q fever. I am puzzled that the army did not give it as a prophylactic."
Mr Bass, from Redditch, Worcestershire, says bringing the case is not about money.
"I'd take a cure over £50m in a second, I want other soldiers and officers to be made aware of the risks of Q fever and the devastating consequences it can have."
The five-day trial, starting on Monday at Central London County Court, will examine the extent of any duty owed by the army to Mr Bass in relation to Q fever, and whether that duty was breached.
Its findings will be based in part on expert medical evidence, with judgement reserved to a later date.