Andrew Useche TB2
Pubic lice are transmitting in the same mediums as the common lice are. They pass through pubic hair, usually during sexual intercourse, or through the clothing of someone that has pubic lice.
Crabs are treated by using prescribed medication that can kill and lice along with their eggs, or a "Nit comb", a specialized comb that can get rid of nits. Clothing and other textiles may also need to be cleaned with hot water or dry cleaning.
Condoms may be able to assist in preventing the spread of crabs, but really, there is no way to properly prevent them; detect the infestation sooner rather and later.