Crab std pictures. With an unaided vision, louse eggs look like small light-colored dots on the hair. The enzyme also causes slight tissue swelling in the bite area. Pubic lice have reduced eyes. Dealing with head lice is comparatively difficult. Close body contact with another person is needed for lice to be passed on. One week after the second treatment, check for lice again. If someone has crabs, inform the sexual partner so they can check for infection and get treatment. Parasites lives everywhere around us.