Not at all. Honestly the big issue with that is how long it sits thawed and what bacterial breakdown happens during that time. If it’s frozen, mostly thawed to process and refrozen the same day that doesn’t leave much time for anything to spoil and with everything in foodsaver bags in single serve portions I thaw to cook under running water about an hour before cooking it. There’s as close to zero risk possible when doing it this way. I wouldn’t recommend thawing and letting it sit around for a week or two then refreezing. But to just partially thaw, portion out, and put back up until time to cook it there isn’t any significant health risks.