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Key information: Arthropod vector-borne diseases are increasingly problematic globally. Ticks rank just behind mosquitoes in terms of their role as vectors for human diseases and are the primary vectors for many animal diseases. Recent studies indicate a link between tick bites and an allergy to red meat, a condition now identified across America, Europe, Asia, and Australia. Humans are incapable of synthesizing the carbohydrate α-Gal (Gal α 1-3Gal β 1-(3)4GlcNAc-R); thus, all α-Gal sources are derived externally, setting the stage for humans to develop a strong immune response to this carbohydrate. The beneficial IgG and IgM antibody responses to α-Gal, stimulated by certain gut microbiota, play a protective role against vector-borne diseases like malaria. Conversely, the harmful anti-α-Gal IgE antibody response, triggered by tick saliva during bites, can lead to Alpha-Gal Syndrome (AGS), characterized by severe allergic reactions to tick bites, cetuximab, gelatinous substances, and red meat. This highlights a dual nature of the immune response to α-Gal: protective against certain pathogens but potentially harmful due to allergies. The link between immunity to α-Gal and varying responses provides a valuable model for studying how immune reactions can both protect against and promote allergies through vector transmission. Notably, individuals with blood type B, especially those who are Rh-negative, are less likely to produce anti-α-Gal IgE antibodies, suggesting a genetic predisposition tied to α-Gal tolerance that mirrors the blood group B antigen structure. This correlation extends to regional variations in blood group B frequency and malaria incidence, emphasizing the complex interplay between blood type and immune responses to α-Gal.