Yes, mosquitoes too have food preferences like us. Just how many of us prefer pizzas over home-cooked food, mosquitoes prefer the blood type O over A, B, or AB. Before getting into the why of this, let's see the differences in all these blood groups. On our blood cells, there are a variety of small rod-like structures called antigens. The antigens also protect you from various diseases. The antigen with a circle or sphere on its tip is the A antigen, and the antigen with a diamond on its tip is the B antigen. So, if a person's blood cells have the A antigen, then they are said to have type A blood, if the B antigen is present, then they are said to have type B blood, and if a person's blood cells have both A and B antigen, then they are said to have type AB blood. Type O blood is sort of unique because it has no antigens present on them. The figure below might help you visualize it better.
(There are more antigens on a blood cell than shown)
Just the lack of antigens in people with blood type O makes them the first choice for mosquitoes' dinner. Scientists also tell us that factors such as how much a person sweats, cries, or secretes lactic acid can help mosquitoes understand their blood groups.
Which blood group is the least preferred by these creatures??
Just like how many people would never eat broccoli until and unless necessary, mosquitoes don't go to people with blood type A until they are confused or have no other option. There is no specific reason that mosquitoes hate type A blood so much. But, we hope to understand that soon.
Mosquitoes can sometimes lay eggs inside your skin which will later tear out your skin to come out. So, the next time a mosquito sits on your hand make sure you don't give her enough time to lay her eggs in you.
Now I know why mosquitoes don’t bite me!
Woah! Never letting a mosquito sit on me long enough.