The Ministry of Defence (MOD) "failed to address the risk" posed to soldiers deployed to Afghanistan by Q fever, a court was told.
Wayne Bass, a private from the 2nd Battalion the Mercian Regiment, said his life has been ruined after serving in Helmand Province in 2011 without being given antibiotics by the Army.
Mr Bass, 34, was medically discharged from the Army in 2014 because of his Q fever, also known as 'Helmand group fevers' and chronic fatigue symptoms.
Humans can catch Q fever after breathing in dust from the faeces of infected farm animals such as sheep, cattle and goats.
The NHS says the bacterial infection is "usually harmless, but can cause serious problems in some people".
Theo Huckle QC told the court his client's case was that there was a "well-established" known risk to soldiers deployed to the area of developing Helmand group fevers, including Q fever.
Mr Huckle told the court: "In essence, the complaint that the complainant makes is that the MOD failed to address the relevant risks, concerned itself with its policy on anti-malarial protection, it did not properly address the risk of Helmand group fevers to the men, and having failed to address the risk, unsurprisingly failed to take any steps to deal with that risk."
Mr Bass's lawyers said he was disabled, suffers from anxiety and depression and symptoms that "greatly affect his life and his functional capacity".
The five-day trial, which started at the Central London County Court on Monday, 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.
In a statement setting out the defendant's case, lawyers for the MOD acknowledged the risk of Q fever was foreseeable.
But it said the claimant "cannot come close" to showing that using Doxycycline as an anti-malarial was the "only reasonable option"
The defence will argue that the claimant "cannot show that the decision not to use Doxycycline as a prophylactic against malaria and Q fever was unreasonable so as to amount to a breach of duty at common law", or that "he would not have sustained injury if he had been prescribed Doxycycline."
In 2017, a soldier struck down with Q fever was awarded compensation by the MOD after Army medics attempted to treat him with paracetamol.
What is Q fever?
The NHS defines Q fever as a "bacterial infection you can catch from infected farm animals".
Usually harmless, it can, in rare cases, lead to pneumonia, hepatitis, organ damage and serious heart conditions. It may also resurface months or years later and long-lasting fatigue, known as Chronic Q fever, can develop.
The most common way Q fever spreads to humans is by close contact with farm animals such as sheep, cattle and goats.
This includes contact with fur and wool, but also with the placenta of the animal, blood, urine and excrement.
Although less likely, Q fever can spread also when drinking milk that has not been pasteurised or through tick bites.
While the infection does not always cause symptoms, some people who contract it can develop flu-like symptoms that can last up to two weeks.
Other symptoms include aching muscles, tiredness, nausea, sore throat, swollen glands, abdominal pain, vomiting and diarrhoea.
There are no formal controls or vaccines available for Q fever in the UK and is difficult to prevent as it can survive in an infectious spore-like form.
Australia regularly vaccinates those in high-risk categories with the Australian licensed vaccine, Q-Vax. These most commonly include vets and farm workers, due to the size of their agricultural industry.
Infected animals generally show little or no symptoms but the organism is highly contagious and spreads quickly amongst herds.
Preventative measures that can be taken include washing hands regularly, covering cuts and grazes, wearing protective clothing and not eating or smoking in areas where animals are kept.