### Lice and Scabies: What You Need to Know **Lice** are tiny parasites that live on humans and feed on blood. They are annoying and contagious but rarely cause serious medical problems. There are three types of lice that can live on people: 1. **Head Lice (Pediculus humanus capitis)**: These are about the size of a sesame seed (2.1 to 3.3 mm long) when adults. Their eggs, called nits, are barely visible whitish or yellow ovals that attach to hair shafts. Head lice are common among schoolchildren and are not related to personal hygiene. They are more common in girls due to more physical contact and sharing of personal items like hats and combs. 2. **Pubic Lice (Pthirus pubis)**: Also known as crab lice, these are yellow-gray parasites found in the pubic region and transmitted by sexual contact. They are 1.1 to 1.8 mm long and cling to hair with their claw-like legs. Pubic lice can sometimes be found in other coarse hair areas like armpits or the chest. 3. **Body Lice (Pediculus humanus corporis)**: Nearly identical in appearance to head lice, body lice are 2.3 to 3.6 mm long. They hide in clothing seams and bedding folds when not feeding. Untreated body lice can cause skin sores or bacterial infections and can spread blood infections. **Scabies** is a skin condition caused by tiny mites called Sarcoptes scabiei. These mites burrow into the skin, causing intense itching and a pimple-like rash. Scabies is highly contagious and spreads through close physical contact. It can affect anyone, regardless of hygiene or living conditions. Both lice and scabies are found worldwide and are common in places where people are in close proximity, such as schools and crowded living conditions.