Communicable diseases spread from person to person, often denoted by the phrase "catching a cold." The causes of communicable conditions include bacteria, viruses, fungi and protozoa, according to the Unionville-Chadds Ford School District. Oftentimes, disease transmission occurs when infected individuals touch inanimate objects such as doorknobs that another person touches and then puts their hands to their face. The nose and mouth are the usual entry points of the microbes. In some cases, diseases of the scalp occur in a similar fashion but contraction usually occurs with direct contact to the head. Scalp diseases require immediate attention. If left untreated they can progress quickly, causing further complications.
Tinea Capitis
Tinea capitis, or ringworm of the scalp, occurs when certain fungi invade healthy hair follicles on the scalp, quickly proliferating causing unsightly lesions and crust. According to DermNet NZ, Trichophyton tonsurans is the most common cause of tinea capitis in the United States, which quickly passes from one person to another as it has a natural proclivity to invade humans. Contraction of these fungi usually occurs in overcrowded living quarters where the fungi can easily contaminate hairbrushes, clothing, towels and the back of seats. Usual symptoms appear as dry scaling, black dots, abscessed or inflamed lesions and yellow crusts in matted hair. General treatments include antifungal shampoos that contain selenium sulfide, zinc pyrithione, providone-iodine and ketoconazole, according to DermNet NZ.
Lice
Head lice do not usually pass on any secondary diseases and are not exactly a health hazard. Instead they can cause insatiable itching, tickling and moving of the hair, irritability, sleeplessness and sores on the head, according to the Centers For Disease Control and Prevention (CDC). Persistent scratching can leave the scalp susceptible to bacterial infection if not properly cleansed and treated. The lice go through a life cycle of eggs, nymphs and adults. The egg phase can last about six to nine days before hatching. When this happens, nymphs emerge, which are visible to the naked eye. Within a week, the lice reach maturation and will be the size of a sesame seed with six legs---each with claws---with a tan to grayish-white color. Adult lice can live up to 30 days on a person's head, the CDC says. Head lice requires lice medication for treatment. Avoid sharing towels, pillows or any items that may be contaminated. Children who contract this disease will need to stay out of school to prevent spreading the lice.
Scabies
Scabies is a communicable skin condition caused by the microscopic mite Sarcoptes scabei, according to MedlinePlus. It affects all types of people and can quickly spread in instances of overcrowded and confined areas such as hospitals, child-care centers and nursing homes. The symptoms on the scalp appear as a pimple-like irritation or a rash, intense itching especially at night and persistent sores, MedlinePlus says. Sharing towels, clothes and bedding quickly spreads scabies, which requires treatment using specialized lotions and solutions.
