Mosquito bites occur when a female mosquito pierces the skin to feed on blood. They use their specialized mouthparts to draw blood, which provides nutrients for their eggs. The bite itself is usually painless, but the saliva injected during feeding can cause an allergic reaction, leading to itching and swelling. The severity of the reaction varies among individuals. Some people may experience mild irritation, while others may have more intense symptoms. Mosquito bites can also transmit diseases such as malaria, dengue fever, and Zika virus, making prevention important in areas where these diseases are common.