FORT COLLINS, Colo. (AP) — There’s an old joke that mosquitoes are like family: They are annoying, but they carry your blood.

Mosquito season is starting to rev up across much of the United States. And that means bug bites.

When a mosquito bites you, it pierces the skin using a mouthpart called a proboscis to suck up blood. As it feeds, it injects saliva into your skin that can cause a reaction — a bump and itching. But the pests can also spread parasites like malaria and viruses like dengue, West Nile and Zika.

So you might want to pause summer vacation planning and consider what to look for in repellents, which keep bugs away from you, and insecticides, which kill them.

WHAT MOSQUITO REPELLENTS WORK BEST?

The Centers for Disease Control and Prevention says that for protection that lasts hours, people should look for ones with these active ingredients: DEET, IR3535, picaridin, or oil of lemon eucalyptus. Those ingredients are registered with the Environmental Protection Agency.