Influenza or Flu is a seasonal disease which outbreaks in various countries including United States.  This flu epidemic mostly emerges during winter season. It can affect all age groups but is usually most severe in the very old and very young. In the United States alone an estimated 36 000 people die each year from influenza and accompanying opportunistic infections and complications. The rate of flu deaths among children while not high are continuing to rise — more than 80 deaths were recorded in the 2007-2008 flu season according to the CDC — highlighting the potential benefit of vaccination. To help prevent disease in young children US health officials recommend annual vaccinations for children between 6 and 10 years old. However a new study published on October 6 in the Archives of Pediatrics & Adolescent Medicine suggests otherwise — that the flu shot in children doesn't necessarily protect them from illness. To know the efficacy of this statement Dr. Peter Szilagyi M.D. M.P.H. of the University of Rochester School of Medicine and Dentistry and Strong Memorial Hospital Rochester N.Y. and researchers at University of Rochester studied 414 children aged 5 and younger who came down with the flu during the 2003-2004 or 2004-2005 flu seasons. These children were compared with over 5 000 controls that did not have influenza during the same seasons. Turns out that flu shots seemed not to make much difference: Kids who got immunized did not get the flu at lower rates than unvaccinated kids. In fact the immunized youngsters were just as likely to be hospitalized or to visit the doctor as kids who never received the vaccine. The Rochester study for example happened to look at the effectiveness of a vaccine during two seasons in which the flu strain included in the vaccine was not well matched to the predominant circulating strain that was making people sick. That could explain the lack of protection among the vaccines — the shot may have been protecting against the wrong flu proteins. Targeting the correct strain is a always a bit of a guessing game however; researchers make their best scientifically based prediction as to which flu virus will be making the rounds in a coming season but they often have to make these predictions up to nine months ahead of time in order to keep up with the lengthy vaccine manufacturing process. Another reason for the flu shot's failure could be the fact that certain forms of the vaccine are more effective than others in children. In this study most of the children received the injected vaccine but recent studies have shown that the nasal spray known as FluMist appears to be better at protecting youngsters from influenza offering the same level of protection at par with the injected vaccine in adults disclosed Dr. William Schaffner of Vanderbilt University School of Medicine and an advisory member of the CDC's Advisory Committee on Immunization Practices. Dr. Geoffrey Weinberg professor of pediatrics at University of Rochester says: "In some circumstances it is like forecasting the weather.  Sometimes we are right on and sometimes we are off."