Varicella vaccine mild and have not been associated with serious complications. Approximately 5% of children who receive the vaccine develop a fever or rash. Adverse reaction reports for the period 1995 to 2005 found no deaths attributed to the vaccine despite approximately 55.7 million doses being delivered. Cases of vaccine-related chickenpox have been reported in patients with a weakened immune system, but no deaths. The literature contains several reports of adverse reactions following varicella vaccination, including vaccine-strain zoster in children and adults. The Varicella zoster vaccine is made from the Oka/Merck strain of live attenuated varicella virus. The virus was initially obtained
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