Prevalence of seafood allergy in the United States determined by a random telephone survey.

BACKGROUND

Seafood allergy is potentially severe, but the prevalence of this group of food allergies in the US population has not been determined.

OBJECTIVE

To estimate the prevalence of seafood (fish, shellfish) allergy in the United States.

METHODS

We performed a nationwide, cross-sectional, random telephone survey by using a standardized questionnaire. Criteria were established in advance to define seafood allergy by report of convincing symptoms and physician evaluation.

RESULTS

A total of 5529 households completed the survey (67.3% participation rate), representing a census of 14,948 individuals. Fish or shellfish allergy defined by established criteria was reported in 5.9% (95% CI, 5.3%-6.6%) of households and among individuals as follows: 2.3% (95% CI, 2%-2.5%) for any seafood allergy, 2% for shellfish, 0.4% for fish, and 0.2% for both types. Seafood allergy was more common in adults compared with children (2.8% vs 0.6%; P <.001) and in women compared with men (3.6% vs 2%; P <.001). Recurrent reactions were reported by 58%, dyspnea or throat tightness was reported by more than 50%, and 16% were treated with epinephrine. Despite this level of acuity, only 8.6% were prescribed self-injectable epinephrine. The rate of reactions to multiple fish among those with any fish allergy was 67%; for Crustacea the rate was 38%, and for mollusks the rate was 49%; only 14% with crustacean allergy reported a mollusk allergy.

CONCLUSIONS

Physician-diagnosed and/or convincing seafood allergy is reported by 2.3% of the general population, or approximately 6.6 million Americans. Affected individuals typically report recurrent and sometimes severe reactions, indicating that seafood allergy represents a significant health concern.