Assessing the impact of shellfish harvesting area closures on neurotoxic shellfish poisoning (NSP) incidence during red tide (Karenia brevis) blooms.

•Karenia brevis produces brevetoxins which may accumulate in molluscan shellfish.•The risk for NSP increases during blooms with ingestion of contaminated shellfish.•The current management strategy is effective for commercially harvested shellfish.•NSP is occurring at a higher rate among non-commercial harvesters.•These include out-of-area state-resident visitors and out-of-state visitors to the SW Florida.