World AIDS Day is now its17th year.It wasfirst observed on December 1,1988 （as,作为） a result of aninternational meeting of health ministers.
They （realized,认识到） that a united global effort was required to stop the （spread,传播） of HIV and AIDS.World AIDS Day is observed annually on December 1.Each year there is a particular （theme,主题） chosen for this （international,国际的） health day.