Varicella zoster virus Varicella zoster virus Varicella zoster virus or varicella-zoster virus (VZV) is one of eight herpesviruses known to infect humans. It causes chickenpox (varicella), a disease most commonly affecting children, teens, and young adults, and shingles (herpes zoster) in adults; shingles is rare in children. VZV is a worldwide pathogen known by many names: chickenpox virus, varicella virus, zoster virus, and human herpesvirus type 3 (HHV-3). VZV infections are species-specific to humans, but can survive in external environments for a few hours, maybe a day or two. VZV multiplies in the lungs, and causes a wide variety of symptoms. After the
Reactive airway disease Reactive airway disease Reactive airway disease is a general term used by many physicians to label patients with symptoms similar to those of asthma. It is most commonly used when a physician is hesitant about formally diagnosing a patient with asthma, which is most prevalent in the pediatric setting for a variety of reasons. While some physicians may use RAD and asthma synonymously, this causes controversy, since RAD can not be used as a real diagnosis for physicians. An exact definition of the condition does not exist. Individuals that are typically labeled as having reactive airway disease, or RAD, generally