For Public Health Officials

  • At the 2021 annual meeting, the Council of State and Territorial Epidemiologists (CSTE) approved a position statement standardizing a case definition for alpha-gal syndrome (AGS).
  • The case definition is for surveillance purposes only and does not replace a clinical diagnosis by a healthcare provider.
  • A standard surveillance case definition provides consistent laboratory and clinical criteria to ensure that data captured across multiple jurisdictions are comparable.
  • AGS is not a nationally notifiable condition.
  • States and local jurisdictions are encouraged, but not required to share information on AGS with members of CDC’s Rickettsial Zoonoses Branch to better understand national trends.

Surveillance case definition pdf icon[PDF – 12 pages]external icon

Alpha-gal testing

  • The main diagnostic test for AGS is a blood test looking for immunoglobulin-E antibodies specific to alpha-gal (alpha-gal sIgE).
    • Tests for alpha-gal sIgE antibodies are available at several large commercial laboratories and may be available at certain academic institutions.
    • LOINC Code: 73837-7 Galactose-alpha-1,3-galactose (Alpha-Gal) IgE Ab [Units/volume] in Serum.
  • Skin tests documenting reaction to certain allergens (such as pork or beef) may also be used to diagnose AGS.