They are spread through close body contact with someone who has them.
The lice crawl from hair to hair but cannot fly or jump. They need human blood to survive, so generally only leave the body to move from one person to another. They do not live on other animals such as cats or dogs.
Pubic lice are most commonly passed on during sexual contact. Condoms will not prevent them from being passed to another person. It is not a reflection of an individual’s personal hygiene.
It is also possible for pubic lice to be spread through sharing clothes, towels and bedding.