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.
Lice don't quickly die without a host, though, and generally survive for three to seven days on their own. The species, age, environmental factors, when they last fed and other specifics can affect exactly how long a louse is able to live off of a host.