They moved to Australia. Years later, they developed an unexpected condition

Key points

• Some migrants develop hay fever years after moving to Australia, even if they never had allergies before. Sydney GP and clinical allergist Dr Jason Yu says allergies can appear at any stage of life, and that exposure to new allergens such as pollen and dust mites may play a role.
• Research has linked migration to higher rates of hay fever and asthma.
• Yu says people with severe breathing symptoms should see a doctor, as thunderstorm asthma can be life-threatening.