Health A-Z

Walking Pneumonia (Atypical Pneumonia)

Clinical Definition Walking pneumonia (atypical pneumonia) is an infectious disease characterized by pulmonary infiltrates. Walking pneumonia is usually clinically milder than other types of pneumonia. The causative agent may vary but is often mycoplasma bacterium. The infection is contagious, and transmission is usually by respiratory droplets from an infected individual. In Our Own Words Walking


Clinical Definition A wart is an abnormal fibrous growth, visible on the skin and caused by a viral infection. Types include common, flat warts, plantar and venereal (Condyloma acuminatum) warts. Caused by direct contact with the contagious human papilloma virus (HPV), warts can spread from person-to-person or via direct contact with an object used by

Weight-Bearing Exercise

Clinical Definition Family practice, Internal medicine, Orthopedics In Our Own Words Weight-bearing exercise can be low-impact, such as stair-step machines, or high-impact, such as running. Bearing weight helps build strong bones and reduces the risk of osteoporosis, the ”brittle bone” disease that can affect both men and women as they age.  Weight-bearing exercise can also

West Nile virus

Clinical Definition West Nile virus is an arthropod-borne flavivirus that is transmitted by mosquitos. Most infected individuals are asymptomatic, but some develop a mild febrile illness; more rarely, individuals develop serious illness such as West Nile meningo-encephalitis. In Our Own Words The West Nile virus is an infection spread by mosquitos. Endemic to Africa, the

Wheat Allergy

Clinical Definition Wheat allergy occurs when the immune system responds in a defensive way to wheat gluten and other proteins. On ingestion, the immune system begins to create specific IgE antibodies against the offending protein. On subsequent consumption, the antibodies bind their target(s), which triggers release of histamines and other chemical signals from immune cells,


Clinical Definition Whiplash is an abrupt flexion or extension movement of the cervical spine. It can potentially damage or strain the neck muscles and ligaments through traumatic movement beyond the natural range of motion. In Our Own Words Whiplash is a condition that occurs when the neck is thrown forward and then backwards in a

Whipworm Infection

Clinical Definition Whipworm infection is a parasitic infection of the large intestine. The causative agent is a nematode of the genus Trichuris. Transmission usually occurs as a result of contact with soil contaminated with whipworm eggs. In some instances, infected individuals may be asymptomatic. In other cases, the infection is characterized by gastrointestinal symptoms, including

Whooping Cough

Clinical Definition Whooping cough is a highly contagious respiratory disease caused by the bacterium Bordetella pertussis. It is characterized by a violent, uncontrollable coughing that makes it difficult to breathe. In Our Own Words Whooping cough occurs when bacteria attach to and damage the cillia in the upper respiratory tract, releasing toxins that cause inflammation.

Wisdom Teeth

Clinical Definition Wisdom teeth (third molars) are the final set of teeth to develop in human beings, and they tend to become impacted and require removal. In Our Own Words Wisdom teeth, also known as third molars, are the final set of human teeth to develop. They are called wisdom teeth because they usually emerge


Clinical Definition Withdrawal is defined as the physical or psychological response to the sudden absence or reduction of a substance that can be addicting, such as alcohol, nicotine or drugs. Among the potential symptoms of alcohol withdrawal are depression and anxiety. A more severe form of alcohol withdrawal is known as delirium tremens or DTs.

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