Why do mosquito bites cause swelling?
The female mosquito is the one that bites as she needs to feed on blood when carrying eggs.Her saliva has proteins to stop us from clotting so she can feed on the flowing blood that’s what causes it to become slightly swollen and itchy.If a more severe reaction happens then the person has a slight allergy to the bite.If the mosquito bites someone with a contagious disease such as malaria then she can then spread this from human to human.