Weeks after the arrival of Brood X, the buzzy swarm of cicadas that emerge from the ground every 17 years to cover trees and sidewalks across a swath of the country, federal health officials have a new warning: People with seafood allergies shouldn’t eat the insects.

The Food and Drug Administration on Wednesday issued the advice to would-be bug-munchers via Twitter, noting that the cicadas “share a family relation to shrimp and lobsters.”

Many chefs and home cooks have been experimenting with recipes incorporating the plentiful cicadas since their arrival in mid-May, wrapping them in rice like sushi, filling tacos with them or using them to garnish chocolate cookies. For the first time in the brood’s long history, they are meeting their ultimate fate in air fryers, the currently voguish cooking appliance.

Our colleagues Kari Sonde and Ann Maloney recently offered a recipe for Spicy Popcorn Cicadas, adapted from the “Cicada-Licious” cookbook by evolutionary biologist and ecologist Jenna Jadin, in which the bugs are marinated, dipped in a peppery batter and pan-fried. Cicada dishes have made appearances on many a local newscast; CNN anchor Brianna Keilar even sampled some on air this week.

Environmental advocates have long promoted eating insects as a sustainable, inexpensive protein source — a practice not traditional in much of the United States — because of their wide availability and the ease of harvesting them. And many experts have likened cicadas to their seafaring counterparts, shrimp, as a means of making them seem less intimidating to wary diners, but that similarity apparently cuts both ways.

All insects belong to the phylum Arthropoda, which refers to their “jointed appendages,” and so do shrimp, lobsters and crayfish, noted Jerome Grant, etymology professor at the University of Tennessee’s Institute of Agriculture. He said he is glad the FDA put out a warning. It’s similar to the ones he posts at his freshman class’s annual “Buggy Buffet,” when all manner of insects are served as a way of calling attention to how important (and delicious) a food source bugs can be.

“If you’re allergic to one, there’s a chance you can be allergic to both,” Grant said. “It’s better to be safe.”

David Stukus, a member of the Asthma and Allergy Foundation of America’s Medical Scientific Council, agreed that people with shellfish allergies should take a better-safe-than-sorry approach. “There’s no good clinical research evaluating the risk of ingesting cicadas for people with shellfish allergies,” he said, “so we are extrapolating.”

Stukus said the allergic reaction people get from eating shellfish happens after they ingest a muscle protein called tropomyosin, which is found not just in shrimp and lobster but in some insects and even in dust mites. To have an allergic reaction to a cicada, a person would have to actually eat it; handling the bugs and their skeletons is fine, even for people with shellfish allergies, he noted.

A report by the U.N. Food and Agriculture Organization about edible insects called for “further investigation” of insect allergies. “Individuals already allergic to crustaceans are particularly vulnerable to developing allergic reactions to edible insects, due to allergen cross-reactivity,” the report said.

And Grant noted that people should also generally avoid eating cicadas raw. “There’s a lot more risk in eating anything raw,” he said.

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