Under 38 C.F.R. § 3.317, VA presumes service connection for Gulf War veterans who have an undiagnosed illness or a medically unexplained chronic multisymptom illness, such as chronic fatigue syndrome, fibromyalgia, or irritable bowel syndrome and other functional gastrointestinal disorders, plus nine infectious diseases. The illness must have appeared during service in the Southwest Asia theater or reached a degree of 10 percent or more by December 31, 2026. That date is close: if this describes you, it is worth acting on now.
No nexus letter is needed for the link to service under this rule. What you need is a disability that fits one of the categories below, evidence it has lasted, and proof of the qualifying service.
Who counts as a Persian Gulf veteran
A "Persian Gulf veteran" under § 3.317(e) served on active duty in the Southwest Asia theater of operations during the Persian Gulf War, which began August 2, 1990 and has no end date yet set. The theater is:
- Countries: Iraq, Kuwait, Saudi Arabia, the neutral zone between Iraq and Saudi Arabia, Bahrain, Qatar, the United Arab Emirates, and Oman.
- Waters: the Gulf of Aden, the Gulf of Oman, the Persian Gulf, the Arabian Sea, and the Red Sea.
- The airspace above all of these.
Because the war has no end date, this covers more than Desert Shield and Desert Storm. Later service in the same theater, including in Iraq after 2003, falls inside it.
The three kinds of qualifying chronic disability
1. Undiagnosed illness
Symptoms that, after history, examination, and lab tests, cannot be attributed to any known clinical diagnosis. The regulation lists signs and symptoms that may be part of one, including fatigue, headache, muscle pain, joint pain, skin problems, neurological or neuropsychological symptoms, breathing problems, sleep disturbances, gastrointestinal symptoms, cardiovascular symptoms, abnormal weight loss, and menstrual disorders.
The odd thing about this category is that a diagnosis can work against you. If a doctor attaches a known diagnosis to the symptoms, they are no longer "undiagnosed," and the claim usually has to go another way, unless the diagnosis is one of the multisymptom illnesses below.
2. Medically unexplained chronic multisymptom illness
A diagnosed illness without a settled cause, marked by overlapping symptoms such as fatigue and pain out of proportion to physical findings. The regulation names three:
- Chronic fatigue syndrome. See the chronic fatigue syndrome rating page.
- Fibromyalgia. See the fibromyalgia rating page.
- Functional gastrointestinal disorders, meaning chronic GI symptoms with no structural cause found. The regulation's note lists irritable bowel syndrome, functional dyspepsia, functional vomiting, functional constipation, functional bloating, functional abdominal pain syndrome, and functional dysphagia. See the IBS rating page.
The list says "such as," so other illnesses that fit the definition can qualify. Illnesses with a partly understood cause, like diabetes or multiple sclerosis, do not.
3. Infectious diseases
Under § 3.317(c), nine infectious diseases are presumptive: brucellosis, Campylobacter jejuni, Coxiella burnetii (Q fever), malaria, Mycobacterium tuberculosis, nontyphoid Salmonella, Shigella, visceral leishmaniasis, and West Nile virus. These also apply to service in Afghanistan on or after September 19, 2001.
Most must have reached 10 percent within one year of leaving the qualifying service. Malaria can also qualify later if medical texts place the start of its incubation period during service. Visceral leishmaniasis and tuberculosis have no time limit. The regulation also lists long-term effects linked to each infection, such as Guillain-Barré syndrome or reactive arthritis, that VA must consider.
What "chronic" and "objective" mean
- Chronic: the disability has lasted 6 months or more, or has come and gone over a 6-month period, under § 3.317(a)(4). Keep a record of when symptoms started.
- Objective indications: signs a doctor can observe, or other non-medical evidence that can be independently verified, under § 3.317(a)(3). Missed work, statements from family or coworkers, and pharmacy records can count toward this. See buddy statements.
The December 31, 2026 deadline
For undiagnosed illness and chronic multisymptom illness, § 3.317(a)(1)(i) requires that the disability appeared during service in the theater, or reached 10 percent or more by December 31, 2026. VA has extended this date before, but as of this writing the regulation says December 31, 2026.
What this means in practice: if your symptoms are already at a rateable level, get them documented in your medical records with dates. The claim itself can be filed later, but the evidence has to show the illness reached 10 percent by that date.
How these conditions are rated
An undiagnosed illness has no diagnostic code of its own. Under § 3.317(a)(5) it is rated by analogy to the condition whose affected functions, location, or symptoms are most similar. Fibromyalgia, chronic fatigue syndrome, and IBS have their own codes.
When VA can deny it anyway
The presumption does not apply if there is affirmative evidence that the disability did not start in the theater, that something after service caused it, or that it came from willful misconduct or alcohol or drug abuse (§ 3.317(a)(7)).
Gulf War veterans and the PACT Act
Gulf War veterans are also covered by the PACT Act's burn pit list, for service from August 2, 1990 in Bahrain, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, Somalia, or the UAE. That list covers cancers, COPD, asthma, chronic sinusitis, chronic rhinitis, and more. A Desert Storm veteran may have claims under both rules. See the PACT Act presumptive conditions list.
If your records are in hand, you can upload them: the first 150 pages are read free, the most important first, which helps you find where your symptoms were first written down.
Frequently asked questions
What are the Gulf War illness presumptive conditions?
Under 38 C.F.R. § 3.317: undiagnosed illnesses; medically unexplained chronic multisymptom illnesses such as chronic fatigue syndrome, fibromyalgia, and functional gastrointestinal disorders including IBS; and nine infectious diseases (brucellosis, Campylobacter jejuni, Q fever, malaria, tuberculosis, nontyphoid Salmonella, Shigella, visceral leishmaniasis, and West Nile virus).
Is IBS a Gulf War presumptive condition?
Yes, as a functional gastrointestinal disorder under § 3.317, if you served in the Southwest Asia theater and it reached 10 percent or more by December 31, 2026 (or appeared during service there). A structural GI disease, one with a physical cause found on testing, is not covered by this rule.
What is the deadline for Gulf War illness claims?
The regulation requires the undiagnosed illness or chronic multisymptom illness to have appeared during service in the theater or reached 10 percent or more by December 31, 2026. The infectious diseases have their own time limits.
Does Afghanistan count for Gulf War illness?
Not for the undiagnosed and multisymptom illness rules, which require service in the Southwest Asia theater. Afghanistan service on or after September 19, 2001 does count for the nine infectious diseases, and Afghanistan counts under the PACT Act's burn pit list from September 11, 2001.
Do I need a diagnosis for an undiagnosed illness claim?
No, that is the point of the category: the symptoms cannot be explained by a known diagnosis. You do need objective indications of the disability and evidence it has lasted at least 6 months.
VA forms mentioned in this guide
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This guide is educational information about the VA claims system — it is not legal or medical advice, and it does not predict or promise any claim outcome. Regulations and procedures change; always verify current requirements at VA.gov. VA Claim Commander is a self-service documentation tool, not a VSO, law firm, or VA-accredited representative.