back pain/severe pain; couldn't hardly take a breath; she couldn't even hardly; \This is a spontaneous report from a contactable consumer. A 66-years-old female patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE, Solution for injection), dose 1 via an unspecified route of administration on 01Apr2021 (Batch/Lot number was not reported) as a single dose for covid-19 immunization. The patient medical history included type 2 diabetes mellitus and back pain (back issue which they knew was a small, herniated disc). There was no family medical history. The patient had no prior vaccinations (within 4 weeks). The concomitant medication was not reported. On an unspecified date in Apr2021, It was reported that he was calling on behalf of his sister-in-law. His sister-in-law got the vaccine because she stayed with his wife and his wife just had triple bypass. So, he signed his sister-in-law up and got her the vaccine and he and his wife had already had the vaccine and they did not have any issues. Prior to his sister-in-law getting the vaccine she had a little bit of a back issue which they knew was a small, herniated disc. She had some issues off and on. She got the first dose of the vaccine and not too long after, about the next day, she started being bothered. His sister-in-law was in severe pain right now. He wanted to go through the steps of where she was at today. He wanted to file a report because at first, he doesnot thought it was related or had anything to do with it. Now he was starting to wonder. Based off the timeline and research on the immune system and how sometimes things can work, he was wondering if it did add to what was going on. It's odd to him what was going on. He was saying something was going on and it's tied to the vaccine. Her pain was bad, and it started right after that first vaccine. He was trying to figure out if it has something to do with the vaccine. Then his sister-in-law got the second booster and from there it was downhill. It was like it amplified a thousand times. He thought it's a side effect or some type of combination between the vaccine. Somehow the vaccine has done something, but he couldnot figure out what. He knew it has done something to cause her immune system to make it worse. He thought it was initiated by the vaccine. He stated hopefully this does not impact her job at all. He does not think it would, but he was concerned for his sister-in-law. The vaccine seems to correlate with the back pain. He doesnot say anything until probably the second week or so after she got the second one. The first, she was kind of like, he thought it's doing something, but he wasnot sure. Then when she got the second one, it amplified it and then she was like yeah, it's got something to do with it. It's bad. His sister-in-law knew with her working here that he was going to investigate it and find out what was going on. He wanted to know everything about it, because he wouldn't think that that would have anything to do with it. His sister-in-law informed him of what was going on sometime in May2021, but she does not remember the exact date. It had to be around the 01may or sometime right around there, about a week or so ago from 22Apr2021. He stated his sister-in-law was a very strong lady. This morning he went in to see her and she couldn't even hardly move or take a breath. She was trying to move around. There was no previous immunization with the Pfizer vaccine considered and no vaccines administered on same date of the Pfizer suspect. The patient had no relevant tests. There was no investigation assessment. The outcome for the event were unknown.  Information on the Lot/Batch number has been requested.