Historic & Scenic Sites in and around Washington County, MO by Esther & Gene Carroll History of Washington County Jails & Courthouses by Esther Carroll These links are a part of Carrolls' Corner - lots of Washington County History!
In a humid environment, over 60% of newly hatched fleas can live without a host for 2 months. In a cool, dry environment, only 10% will live without an immediate host. Humidity is the key to flea survival.
Before becoming adult fleas, the larvae transform into pupae within a silk-like cocoon. Pupae remain inside the cocoon for 2 to 4 weeks, sometimes longer. The cocoon is resistant to insecticides and this is why some adult fleas are seen for an extended period, even after the home and pet are treated.