Most go away without issue but mosquito bites can become infected, especially if you scratch them too much.
"If they go from being a little bit red and swollen to being larger, red and swollen, having any kind of yellowish drainage or crusting over them, or they appear to be getting warmer and larger - you really should let someone know," said Dr. Danziger-Isakov.
Mosquitoes can carry West Nile Virus, ticks can carry Lyme disease, and one type of the disease can even trigger sudden allergies to red meat.
In addition, a bacteria on fleas and ticks was recently linked to rheumatoid diseases like fibromyalgia.
Veterinarian Marty Becker has written dozens of pet care books and says non-pet owners can even be exposed to fleas on the beach.
"A lot of time at night, that's the feral cats litter box. Some other things wash up on shore so it's a good idea to put a towel down to protect your family with," he said.
Finally Dr. Becker says pets should be given medication that prevent fleas, ticks, and other parasites from staying on them.