No, the poison ivy
blisters are the caused by the body's natural allergic reaction to
the plants. If the blisters break and ooze, the fluid does not
contain the oil that causes spreading.
The rash-causing oil, called urushiol, from the original contact
with poison oak and poison ivy will continue spreading (unless
removed) for the first one or two days. It is found in in all parts
of poison ivy, oak and sumac plants whether dead, dormant or
If new areas of rash appear after three days, and you have not
been in contact with the plants, you are most likely getting
re-exposed to the oil from contaminated clothing, tools, or even
your cat or dog.