Head lice / louse
Head lice are wingless insects spending their entire lives on the human scalp and feeding exclusively on human blood. Humans are the only known hosts of this specific parasite, while chimpanzees host a closely related species, Pediculus schaeffi. Other species of lice infest most orders of mammals and all orders of birds, as well as other parts of the human body.
Lice differ from other hematophagic ectoparasites such as fleas in spending their entire lifecycle on a host. Head lice cannot fly, and their short, stumpy legs render them incapable of jumping, or even walking efficiently on flat surfaces.
The non-disease-carrying head louse differs from the related disease-carrying body louse (Pediculus humanus humanus) in preferring to attach eggs to scalp hair rather than to clothing. The two subspecies are morphologically almost identical, but do not normally interbreed, although they will do so in laboratory conditions. From genetic studies, they are thought to have diverged as subspecies about 30,000–110,000 years ago, when many humans began to wear a significant amount of clothing. A much more distantly related species of hair-clinging louse, the pubic or crab louse (Pthirus pubis), also infests humans. It is visually different from the other two species and is much closer in appearance to the lice which infest other primates. Lice infestation of any part of the body is known as pediculosis.
Head lice (especially in children) have been, and still are, subject to various eradication campaigns. Unlike body lice, head lice are not the vectors of any known diseases. Except for rare secondary infections that result from scratching at bites, head lice are harmless, and they have been regarded by some as essentially a cosmetic rather than a medical problem. Head lice infestations might be beneficial in helping to foster a natural immune response against lice which helps humans in defense against the far more dangerous body louse, which is capable of transmission of dangerous diseases.
Scottsbluff is a city in Scotts Bluff County, in the western part of the state of Nebraska, in the Great Plains region of the United States. The population was 15,039 at the 2010 census. Scottsbluff is the largest city in the Nebraska Panhandle, and the 13th largest city in Nebraska.
Scottsbluff was founded in 1899 across the North Platte River from its namesake, a bluff that is now a U.S. National Park called Scotts Bluff National Monument. The smaller town of Gering had been founded south of the river in 1887. The two cities have since grown together to form the 7th largest urban area (Scottsbluff Micropolitan Statistical Area) in Nebraska.