Varicella zoster virus countries. Varicella vaccination has raised concerns in some that the immunity induced by the vaccine may not be lifelong, possibly leaving adults vulnerable to more severe disease as the immunity from their childhood immunization wanes. Vaccine coverage in the United States in the population recommended for vaccination is approaching 90%, with concomitant reductions in the incidence of varicella cases and hospitalizations and deaths due to VZV. So far, clinical data has proved that the vaccine is effective for over 10 years in preventing varicella infection in healthy individuals and when breakthrough infections do occur, illness is typically mild. In 2007,
Technical diving diving" has been credited to Michael Menduno, who was editor of the (now defunct) diving magazine "aquaCorps Journal". The concept and term, "technical diving", are both relatively recent advents, although divers have been engaging in what is now commonly referred to as technical diving for decades. The term "technical diving" can be traced back to the cover story of the first issue of "AquaCorps" magazine, in early 1990, titled "call it "High-Tech" Diving" by Bill Hamilton, describing the current state of recreational diving beyond the generally accepted limits, such as, deep, decompression and mixed gas diving. By mid 1991, the