The U.S. Food and Drug Administration approved the vaccine Boostrix against tetanus, diphtheria and whooping cough for those age 65 and older, officials say. Leonard Friedland, vice president for clinical and medical affairs at GlaxoSmithKline Pharmaceuticals, says the approval of Boostrix for the elderly was based on two clinical trials in which more than 1,100 U.S. subjects received the vaccine. \"A growing segment of our population, adults age 65 and older, can now help protect themselves from whooping cough, a serious and highly contagious respiratory disease,\" Friedland says in a statement. \"Although many people may have been vaccinated against whooping cough as children, immunity can wear off over time. Adults, including those age 65 and older, should speak with their healthcare providers to make sure their vaccinations are up to date and to discuss the Centers for Disease Control and Prevention\'s recommendations for preventing tetanus, diphtheria and pertussis.\" In 2010, California declared a whooping cough epidemic and several states reported increases in cases in 2010 compared to 2009. Another study estimates that pertussis, or whooping cough, may affect as many as 3.3 million U.S. adolescents and adults each year, Friedland says. Whooping cough starts off like the common cold and can turn into a persistent cough that can linger up to 100 days in some people.