Varicella zoster virus and safe in adults with Human Immunodeficiency Virus. Chickenpox-like rashes were recognised and described by ancient civilizations; the relationship between zoster and chickenpox was not realized until 1888. It was in 1943 that Ruska noticed the similarity between virus particles isolated from the lesions of zoster and those from chickenpox. In 1974 the first vaccine was introduced for chickenpox. 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
Technical diving magazine was using the term "technical diving", as an analogy with the established term "technical (rock) climbing". In the US the Occupational Safety and Health Administration categorises diving which is not occupational as "recreational diving" for purposes of exemption from regulation. This is also the case in some other countries, including South Africa. There is some professional disagreement as to what exactly technical diving encompasses. Nitrox diving and rebreather diving were originally considered technical, but this is no longer universally the case as several certification agencies now offer Recreational Nitrox and recreational rebreather training and certification. Some training agencies classify