As of January 19th, 2012, veterans with service connected ALS will be eligible for a 100% disability rating.
Veterans with ALS - New Disability Rating Rule
Evidence supports the conclusion that people who have served in the military, regardless of what branch and era of service, are at a greater risk of developing ALS than those who have not served in the military. Veterans with ALS are eligible for Disability Benefits.
38 CFR part 4 states that:
the disability evaluation criterion for ALS will provide a total disability rating for veterans with service-connected ALS. This will eliminate the need to for veterans to reapply for disability ratings as their disease progresses. The ruling goes into effect January 19, 2012.