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.
A flea can live for up to 100 days if it has food. A flea will live  for only a week if it is newly formed and hasn't eaten. 1 person found this useful.