Cow’s milk

Cow’s milk Scientific Information
Type: Whole Allergen
Display Name: Cow's milk
Allergen code: f2
Family: Bovidae
Genus: Bos
Species: Bos domesticus/taurus
Route of Exposure: Ingestion
Latin Name: Bos taurus
Other Names: Domesticated cow
WHO/ICD-11 code: XM6RB2

Summary

Cow’s milk (CM) is a nutrition-rich (proteins, calcium, vitamins, and energy) food typically consumed after processing. Globally, CM is one of the foods popularly consumed by infants, children, and adults. However, allergy to CM is prevalent among infants and young children during the first year of life, affecting 0.5-3% at the age of 1 year. Dairy products based on milk (such as cheese, butter, cream, and yogurt) or baked milk products (such as baked muffins and pizza) are also consumed worldwide. The major allergens found in CM are casein in milk coagulum, α-lactalbumin, and β-lactoglobulin in milk whey. Casein possesses a high degree of allergenicity and antigenicity compared to whey proteins and is a heat-stable protein resistant to processing. On the contrary, whey proteins in milk allergens are reported to be heat labile and affected by processing. Milk sensitization is regarded as a prerequisite for immunoglobulin E (IgE)-mediated milk allergy and is found to be more prevalent than milk allergy. Clinical manifestations of CM allergy (CMA) can be both IgE-mediated [like anaphylaxis, cutaneous reactions, angioedema, urticaria, vomiting, aggravation of atopic dermatitis, gastrointestinal (GI) symptoms, asthma, allergic rhinitis, and rhinoconjunctivitis] and non-IgE mediated (GI symptoms like diarrhea, reflux, abdominal discomfort, mucus, blood in the stool, vomiting, etc.) reactions. Therefore, milk-allergic individuals are recommended to avoid milk and milk-based products in their diet. Additionally, oral immunotherapy might be an effective treatment option for young children with CMA. Most milk-allergic infants are reported to develop clinical tolerance naturally towards CM by 5 years. Moreover, the development of CM tolerance has been reported in children after the early introduction of CM protein as a supplement to breastfeeding during weaning and also by introducing baked-milk products into the diet of children with CMA. An oral food challenge is considered the gold standard for diagnosing CMA. Moreover, milk sIgE testing is also used as an aid in diagnosing milk allergy and monitoring disease development. Persistent sensitization to milk has been regarded as a strong predictor for the later development of aeroallergen sensitization and respiratory diseases in pediatrics. Furthermore, CM has been found to be cross-reactive with buffalo, sheep, camel, goat, mare, and donkey milk; CM-based products has also been reported to be cross-reactive with beef, and cow dander.