Tropical Disease Residuals (38 CFR 3.309(b)) VA Disability Rating
- Service connection requires a current diagnosis, an in-service event or exposure, and a medical link (nexus) between the two.
- VA assigns ratings of 0% to 100% under diagnostic code 6300s, using the criteria in the rating table below.
- The percentage assigned turns on Active infection or residuals.
- Presumptive service connection may apply under the Tropical Service for veterans with qualifying service.
| Rating | Criteria |
|---|---|
| 100% | Active disease, for infections rated as total while active under their diagnostic codes. |
| 0% | Inactive without residuals. Lasting residuals (organ damage, neuropathy, anemia) are rated under the matching body system codes. |
Illustrative scenarios showing how the criteria above are applied. These are educational examples, not a prediction of any individual veteran's rating.
Active disease
Illustrates 100%Situation. The tropical disease is active.
How the criteria apply. Active disease is rated 100 percent while active under its diagnostic code (DC 6300 series).
Inactive, rated on residuals
Illustrates 0%+Situation. Once inactive, lasting residuals such as organ damage, neuropathy, or anemia set the rating.
How the criteria apply. When inactive without residuals it rates 0 percent; lasting residuals are rated under the matching body-system codes.
Malaria, leishmaniasis, and schistosomiasis have their own pages on this site. This page is the catch all for the rest of the statutory list, which still matters for veterans of tropical deployments.
What VA looks at
Laboratory confirmation of the infection, service in an endemic area, the timing against the incubation period, and each documented residual.
Common exam and DBQ topics
Where and when exposure happened, the acute illness, treatments, and what never went back to normal.
Evidence that usually matters
Infectious disease records, parasitology and serology results, deployment records, treatment history.
Common misunderstandings
The one year presumption window stretches when the disease's incubation period explains a later onset, and treatise evidence on incubation is acceptable proof. Residuals, not the cured infection, carry the long term rating.
Drawn directly from the VA Disability Benefits Questionnaire (DBQ). The examiner records each item below; the rating then maps to the table above.
- Confirm the specific tropical disease from laboratory records.
- Establish endemic area service and the onset timeline.
- Apply the incubation period rule for late appearing disease.
- Rate each residual under its matching code.
Small rules in the regulations decide a surprising number of claims. These are the ones that most often change a tropical disease residuals (38 cfr 3.309(b)) outcome. None of this is legal advice; it is a map of where to look.
- What you and people around you witnessed is real evidence
You do not always need a doctor to prove a symptom you can see, hear, or feel. Statements from you, family, or fellow service members about things like pain, ringing in the ears, or panic attacks are competent lay evidence under 38 CFR 3.159. A clear buddy statement with dates and specifics can carry weight.
38 CFR 3.159 - A tie goes to you
When the evidence for and against a point is roughly equal, VA is required to decide in the veteran's favor. This benefit of the doubt rule lives in 38 CFR 3.102. You do not have to prove a claim beyond all doubt, only to bring the evidence to about even.
38 CFR 3.102 - An unbroken line of symptoms can stand in for a paper trail
For certain chronic conditions, showing symptoms that continued from service to now can help establish service connection even without a perfect record. This continuity of symptomatology idea comes from 38 CFR 3.303(b) and applies to the chronic diseases the regulation lists.
38 CFR 3.303 - If it happened in combat, your word can be enough that the event occurred
For anyone who served in combat, VA must accept your own account of what happened during that combat as proof the event took place, as long as it fits the conditions of your service, even when no record survives. This comes from 38 U.S.C. 1154(b). It does not by itself prove the injury, but it can establish the in service event.
38 U.S.C. 1154(b) - If it was not written down at entry, you are presumed to have entered healthy
Unless a condition was noted on your entrance exam, the law presumes you were sound when you entered service. To rebut that, VA has to show by clear and unmistakable evidence both that the condition existed before service and that service did not make it worse. See 38 CFR 3.304(b).
38 CFR 3.304 - You can reopen a denied claim with new and relevant evidence and keep your date
After a decision, a Supplemental Claim lets you add new and relevant evidence. If you file it within one year of the decision, you protect your original effective date, so back pay can reach further. See 38 CFR 3.2501.
38 CFR 3.2501 - Some conditions are presumed if they show up within a year of getting out
Certain chronic diseases, including hypertension, arthritis, and diabetes, that appear to a compensable degree within one year of leaving service are presumed connected to service, even without proof of a specific cause. See 38 CFR 3.307 and the list in 3.309.
38 CFR 3.309 - A diagnosis years later can still be service connected
A condition first diagnosed long after you left service can still be service connected if the evidence ties it back to something in service. You do not need a diagnosis while still in uniform. See 38 CFR 3.303(d).
38 CFR 3.303
- The same symptom is rated once, but separate problems are rated separately
VA cannot rate the same symptom twice, which is pyramiding under 38 CFR 4.14, but it can and should rate distinct problems on their own. A scar and the loss of motion under it, for example, can each be rated. The Esteban decision is the classic example.
38 CFR 4.14 - One service connected condition can open the door to another
A condition caused by, or made worse by, a service connected condition can be service connected too. Sleep apnea linked to weight gain from a service connected condition, or depression linked to chronic pain, are common examples. This secondary path is in 38 CFR 3.310.
38 CFR 3.310 - Your rating can change by time period
If a condition was worse during one stretch and better during another, VA can assign different ratings for those periods rather than one flat number. These are called staged ratings, and they flow from VA's duty to consider the whole recorded history under 38 CFR 4.1 and 4.2.
38 CFR 4.2 - Ratings are combined with a table, not added
Two disabilities at 50 and 50 do not make 100. VA combines them with the table in 38 CFR 4.25, working from the largest down, then rounds to the nearest 10 only at the very end. This is why a 30 and a 20 can land on 40, not 50.
38 CFR 4.25 - If the schedule does not fit your case, VA can rate outside it
When your disability picture is so unusual that the normal rating schedule does not capture it, for example frequent hospital stays or marked interference with work, VA can refer the case for an extraschedular rating. It is uncommon but real, under 38 CFR 3.321(b)(1).
38 CFR 3.321 - When you are between two ratings, the higher one should win
If your symptoms sit between two rating levels, VA is supposed to assign the higher one when your overall disability picture more nearly matches it. This is the reasonable doubt rule applied to ratings, in 38 CFR 4.7.
38 CFR 4.7 - You do not have to check every box on the list
The symptoms listed at each rating level are examples and guides, not a strict checklist. VA is not supposed to deny a level just because you do not have every single symptom named. See 38 CFR 4.21.
38 CFR 4.21
- You can lock in your start date before the full claim is ready
Filing an intent to file holds your effective date for up to a year while you gather evidence. If you complete the claim within that year, back pay can run from the intent to file date, not the later submission. See 38 CFR 3.155.
38 CFR 3.155 - Older ratings get harder to take away
A rating in place for 5 years is treated as stabilized, one in place for 10 years has protected service connection, and one in place for 20 years generally cannot be reduced below its level except for fraud. See 38 CFR 3.344, 3.957, and 3.951.
38 CFR 3.344 - VA cannot cut a rating without showing real, lasting improvement
To reduce a rating, VA generally has to show actual improvement under the ordinary conditions of life and work, not just one better exam. The rules are in 38 CFR 3.344, and a proposed reduction comes with notice and a chance to respond first.
38 CFR 3.344 - You can be paid at the 100 percent rate without a 100 percent rating
If service connected conditions keep you from holding steady, gainful work, VA can pay you at the 100 percent rate through TDIU, even if your combined rating is lower. Under the Rice decision, VA must consider TDIU whenever the record raises it, even if you never asked for it by name. See 38 CFR 4.16.
38 CFR 4.16 - Your back pay date is worth checking yourself
Your award usually runs from the date you filed or the date entitlement arose, whichever is later, with special rules for claims filed within a year of leaving service. Knowing your effective date under 38 CFR 3.400 is how you catch retroactive pay that came up short.
38 CFR 3.400 - A clear error in an old decision can be fixed back to day one
A final decision that contained a clear and unmistakable error can be revised at any time, and the correction runs back to the original date, not the date you pointed out the error. The bar is high: the error has to be undebatable. See 38 CFR 3.105(a).
38 CFR 3.105 - Needing help at home can add money on top of your rating
If you need help with everyday activities, or are largely confined to your home because of disability, you may qualify for Aid and Attendance or Housebound payments added to your monthly amount. See 38 CFR 3.350 and 3.352.
38 CFR 3.352 - Surgery can earn a temporary 100 percent rating while you heal
After certain surgeries, or when a service connected joint is immobilized in a cast, VA can grant a temporary 100 percent rating during recovery and then return you to your prior rating. It is easy to miss because you have to flag it. See 38 CFR 4.30.
38 CFR 4.30 - A long hospital stay can pay at 100 percent for that time
If you are hospitalized more than 21 days for a service connected condition, VA can pay you at the 100 percent rate for that period, then drop back to your regular rating afterward. See 38 CFR 4.29.
38 CFR 4.29 - Even a 0 percent rating is worth winning
A 0 percent rating still confirms the condition is service connected. That opens the door to secondary claims, to an increase later if it worsens, and can affect VA health care priority. Do not walk away from a noncompensable grant. See 38 CFR 4.31.
38 CFR 4.31 - A new law can pay you back to its start date
When a new law or presumption adds a condition, your benefits can reach back to the law's effective date, up to one year before you filed. This matters for PACT Act and other presumptive expansions. See 38 CFR 3.114.
38 CFR 3.114 - If VA later finds lost service records, your date can reach back
When VA later locates relevant official service records it did not have the first time, it must reconsider the claim, and the effective date can run back to your original filing, even years later. See 38 CFR 3.156(c).
38 CFR 3.156 - An increase can be backdated up to a year
For a condition that got worse, your higher rating can be paid up to one year before you filed, if the record shows the worsening was clearly there during that window. See 38 CFR 3.400(o)(2).
38 CFR 3.400 - One total rating plus 60 percent more can mean extra money
If you have a single disability rated 100 percent and other service connected disabilities adding to 60 percent or more, you may qualify for housebound special monthly compensation, paid on top of the 100 percent rate. See 38 CFR 3.350(i).
38 CFR 3.350
Find medical studies for Tropical Disease Residuals )
These search starters open PubMed and PubMed Central (the National Library of Medicine's free databases) pre-filled for this condition. Strong, peer reviewed studies can help a qualified provider write a more persuasive nexus opinion.
Studies on how this condition develops and what raises the risk.
Research on how this condition is associated with or follows another.
Systematic reviews and meta analyses that summarize many studies.
Read complete studies for free in PubMed Central.
You have three review lanes, pick the one that fits the situation.
Under the Appeals Modernization Act (38 CFR 3.2500), a Higher Level Review or a Board Appeal must be requested within one year of the decision notice. A Supplemental Claim can generally be filed at any time after the decision, but filing any of the three within that one year window is what keeps the claim continuously pursued and protects the original effective date; wait longer and a later award may start from the new filing date instead.
Related conditions
Background reading
Supplemental articles that connect to this condition.
VA recognizes that certain illnesses are presumed service connected for veterans with qualifying service in specific times, places, or duty assignments. This guide walks every active presumptive category, what it covers, and the rule cites.
A Compensation and Pension exam gathers the facts VA needs to rate a claim. Here is who runs it, why VA orders one, how to prepare, what to say about your worst days and flare-ups, what happens if you miss it, and how to read the report.
Since Feb 19, 2019, a veteran who disagrees with a VA decision picks from three review lanes: Higher Level Review, Supplemental Claim, or Board Appeal. This is a Walkthrough what each lane is, what it requires, what it costs in time, and how to keep your effective date protected.
Your rating may also qualify you for state-level benefits.
VA compensation is federal, but every state layers its own benefits on top. Many states reduce or waive property tax for disabled veterans, and many offer license, tuition, or vehicle benefits at various rating levels. The thresholds, dollar amounts, and eligibility rules vary widely from state to state, so the reliable answer is always your own state's guide.
Put this rating to work
Free calculators and a guide to turn a rating percentage into real numbers. Your figures stay on your device unless you ask us to email an estimate.
Add this condition to your other ratings using VA math, not simple addition.
See the 2026 monthly payment for a rating, including dependents.
Estimate retroactive pay from your effective date.
How one service connected condition can support a claim for another.
Most recent human review on this page, July 5, 2026. Below is the review history across this page, its citations, and the supplemental articles it links to.
- July 5, 2026articleAppealing or Continuing a VA Decision: The Three Lanes Under the AMA
- July 5, 2026articleThe C&P Exam: What to Expect and How to Prepare
- July 5, 2026articleVA Presumptive Conditions, Category by Category
- June 13, 2026conditionThis page
- June 13, 2026citation38 CFR Part 4 Schedule for Rating Disabilities