Most experts agree that as soon as you see the first flea, it’s time to treat your home and pets. That’s because a female flea can lay 50 eggs per day, around 2,000 in their short lifetime. Those hatch and can become mature adult fleas within two weeks to several months depending on the conditions. It's best to take care of this problem right away, because when fleas get out of control, they can cause a number of problems for you and your pet. Beyond being annoying, fleas can spread diseases and parasites. Some pets are mildly to severely allergic to flea saliva and can experience discomfort even from a single flea bite. If you’ve ever had fleas bloom in your home, you’ll remember the urge to itch the bites. That urge can make your pet to lick and scratch themselves until they develop secondary problems like skin infections, hot spots, and even behavior problems like destroying furniture out of frustration.