“Fluid in the blisters does not contain the toxic poison oak chemical, urushiol. If the blisters break, the fluid will not cause the poison oak to spread.
Scratching other parts of the body with contaminated fingernails can spread poison oak. The toxic chemical can remain under the nails for several days unless carefully removed by thorough cleaning of the nails.
A person who has washed thoroughly and has changed into clean clothing cannot spread poison oak. The only way to become a victim of poison oak is to make direct contact with the toxic resin. This is possible by coming in contact with a contaminated person who has not washed properly or changed into clean clothes.”