Yes, it is unsafe to eat shrimp or fish that has been left out on the counter overnight and then refrigerated, especially if this has happened twice. Seafood is highly perishable and can quickly develop harmful bacteria if not handled and stored properly.
When seafood is left at room temperature (in the "danger zone" of 40°F to 140°F or 4°C to 60°C) for an extended period, bacteria can multiply rapidly, leading to potential foodborne illnesses. Refrigerating the seafood after it has been left out will not fully stop bacterial growth, as refrigeration only slows down the process rather than halting it entirely.
Leaving seafood at room temperature for an extended period, not once but twice, significantly increases the risk of bacterial contamination. Even if the seafood doesn't show any obvious signs of spoilage, it may still harbor harmful bacteria that could make you sick.
To ensure food safety and avoid the risk of foodborne illnesses:
Always refrigerate seafood promptly: If you have cooked or raw seafood that you don't plan to eat immediately, refrigerate it within two hours of cooking or purchasing.
Store seafood properly: Keep seafood in airtight containers or sealed bags in the refrigerator to prevent cross-contamination and avoid the transfer of odors.
Consume within a safe timeframe: Cooked seafood should be consumed within 3 to 4 days of refrigeration, while raw seafood should be consumed within 1 to 2 days.
When in doubt, throw it out: If you're uncertain about the safety of seafood that has been left out for an extended period, it's best to discard it rather than risk potential food poisoning.
Remember, seafood is highly sensitive to temperature abuse, so it's crucial to handle and store it properly to ensure food safety.