There are many causes of hives, and the most common is related to genetics. If one of the parents has an allergic constitution, then the likelihood of allergies in their offspring significantly increases. Environmental factors also play a role in the occurrence of hives. For example, environments with a lot of dust or dust mites can trigger allergic reactions. Additionally, a humid living environment can promote the growth of fungi, which can also cause hives. The occurrence of hives is also related to food. Individuals who are allergic to proteins might experience hives when consuming high-protein foods like fish, shrimp, crabs, milk, and eggs. Furthermore, viral infections, bacterial infections, and parasite infections can also trigger hives.