As long as the veteran (1) served in a qualifying area of Southwest Asia during the qualifying dates; (2) has a qualifying chronic disability; and (3) this qualifying disability has manifest during a presumptive period, then the veteran qualifies for presumptive service connection for this disability.
The qualifying areas for this presumption are Iraq, Kuwait, Saudi Arabia, any neutral zone between Iraq and Saudi Arabia, Bahrain, Qatar, the United Arab Emirates, Oman, Afghanistan, the Gulf of Aden, the Gulf of Oman, the Persian Gulf, the Arabian Sea, the Red Sea, and the airspace above these locations. The qualifying dates are August 2, 1990, to the present. It is important to note that this list of qualifying areas does not include some countries where veterans were also exposed to toxins, such as Turkey. This does not mean that veterans who only served in Turkey are ineligible for disability compensation benefits, it simply means that they are not entitled to “Presumptive Service Connection” and therefore they have the additional hurdle of showing an actual in-service event that caused their disability.
The qualifying chronic disabilities include: (A) an undiagnosed illness; (B) a medically unexplained chronic multisystem illness that is defined by a cluster of signs or symptoms, (C) or, for those serving in theater after September 19, 2001, an infectious disease designated by Congress. In order to be chronic, the symptoms must have existed for at least six months.
(A) Undiagnosed Illness
In order to be an “undiagnosed illness,” the signs or symptoms must not be attributed to any known clinical diagnosis. 38 U.S.C. § 1117(g) states that an undiagnosed illness includes:
(g) For purposes of this section, signs or symptoms that may be a manifestation of an undiagnosed illness or a chronic multisymptom illness include the following:
(2) Unexplained rashes or other dermatological signs or symptoms.
(4) Muscle pain.
(5) Joint pain.
(6) Neurological signs and symptoms.
(7) Neuropsychological signs or symptoms.
(8) Signs or symptoms involving the upper or lower respiratory system.
(9) Sleep disturbances.
(10) Gastrointestinal signs or symptoms.
(11) Cardiovascular signs or symptoms.
(12) Abnormal weight loss.
(13) Menstrual disorders.
It’s important to note that if a veteran’s fatigue is diagnosed as chronic fatigue syndrome, that veteran is no longer qualified under the provision for an undiagnosed illness. However, the veteran would qualify under the provision for a medically unexplained chronic multisystem illness.
(B) Medically Unexplained Chronic Multisystem Illness
38 C.F.R. § 3.317(a)(2)(ii) defines “medically unexplained chronic multisystem illness” as:
A diagnosed illness without conclusive pathophysiology or etiology, that is characterized by overlapping symptoms and signs and has features such as fatigue, pain, disability out of proportion to physical findings, and inconsistent demonstration of laboratory abnormalities. Chronic multisymptom illnesses of partially understood etiology and pathophysiology, such as diabetes and multiple sclerosis, will not be considered medically unexplained, that is defined by a cluster of signs or symptoms, such as fibromyalgia, chronic fatigue syndrome, and irritable bowel syndrome;
Currently under this umbrella, the VA includes chronic fatigue syndrome, fibromyalgia, and functional gastrointestinal disorders other than structural gastro intestinal diseases. This list is simply a sample and is not exhaustive. The regulation further defines “functional gastrointestinal disorder as:
A group of conditions characterized by chronic or recurrent symptoms that are unexplained by any structural, endoscopic, laboratory, or other objective signs of injury or disease and may be related to any part of the gastrointestinal tract. … These disorders are commonly characterized by symptoms including abdominal pain, substernal burning or pain, nausea, vomiting, altered bowel habits (including diarrhea, constipation), indigestion, bloating, postprandial fullness, and painful or difficult swallowing. Diagnosis of specific functional gastrointestinal disorders is made in accordance with established medical principles, which generally require symptom onset at least 6 months prior to diagnosis and the presence of symptoms sufficient to diagnose the specific disorder at least 3 months prior to diagnosis.
(C) Infectious Disease designated by Congress
As of this date, Congress has designated brucellosis, campylobacter jejuni, coxiella burnetti (Q fever), malaria, mycobacterium tuberculosis, nontyphoid salmonella, shigella, visceral leishmaniasis, and West Nile virus. The veteran would have had to have served in theater after September 19, 2001, to qualify under this provision.
In order to qualify for either an undiagnosed illness or a medically unexplained chronic multisystem illness, the veteran would need to have either the condition manifest to any degree while in theater or to a degree of ten percent (10%) or higher sometime before December 31, 2016. Most presumptive periods for infectious diseases designated by Congress run for up to one year from separation from Southwest Asia, not one year from separation from military service. However, certain diseases have their own presumptive periods and these periods are tied to medical treatises. There is no time limit within which visceral leishmaniasis or mycobacterium tuberculosis must manifest to a degree of ten percent (10%) or more.
 See 38 C.F.R. §3.317(e)(2) and VA Training Letter 10-01 (Feb. 4, 2010).
 38 C.F.R. § 3.317(a)(1)(ii).
 38 C.F.R. § 3.317(a)(2)(i)(B).
 38 C.F.R. § 3.317(c)(2).