Lance Cpl. Josef Lopez still suffers from injuries he began experiencing in Iraq three years ago — injuries caused not by bombs or guns but by a military-administered smallpox vaccine he got before he left the United States.

The shot, which the military strongly encourages troops to get, triggered a rare bad reaction in the Marine from Missouri — leaving the then-20-year-old Lopez in a coma, paralyzed for several weeks and unable to breathe, McClatchy Newspapers reported.

Lopez hasn't been the same since. He's regained the ability to walk, but he limps. His loss of bladder control means he has to wear a urine bag. He takes about 15 pills a day to treat leg spasms and other conditions.

Now, Lopez and his family are upset because the government says he isn't eligible for a special benefit of up to $100,000 for members of the military who have suffered traumatic injuries.

The Department of Veterans Affairs, which has covered the cost of his regular medical expenses, says that because his health problems were caused by the vaccine, he can't collect the additional benefits that would provide funds to build him a wheelchair lift or help defray money lost while his mother has stopped working to tend for him.

"It's for traumatic injury, not disease; not illness; not preventive medicine," Stephen Wurtz, the deputy assistant director for insurance at the VA, told McClatchy Newspapers. "It has nothing to do with not believing these people deserve some compensation for their losses."

Lopez and his mother, Barbara Lopez — who flew to her son's aid in 2006 when the mysterious illness took over and the chance of recovery seemed grim — have appealed to Sen. Claire McCaskill of Missouri for help.

McCaskill has drafted a bill that would extend benefits to include those adversely affected by vaccines, KOMU.com reported.

"It would give him the same coverage, and frankly, I really think we need to take care of this young man and his family," McCaskill said in an interview with KOMU TV. "He was willing to take care of us."

Lopez said he feels as though the government has let him and others in a similar situation down by "twisting the rules around to deny people who actually deserve the money."

"It's kind of disappointing because there's so few of us affected that it's hard to get our voices heard and get equal treatment," he told FoxNews.com. "I feel like we've been pushed around a little bit."

The traumatic injury program has granted almost 6,700 claims — 63 percent of those received — and paid $394 million in compensation as of July 1, according to Wurtz. Lopez is fighting to be compensated, too.

"I could have easily died, or not been able to walk because of that," Lopez told McClatchy Newspapers. "It destroyed my world. It was pretty traumatic to me."

VA officials insist the agency is complying with what they interpret was the intent of Congress in creating the benefit legislation.

The department couldn't say how many claims have been denied because of injuries or illnesses related to immunization shots — but Wurtz and others estimated it was probably a small number, McClatchy Newspapers reported.

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