The FDA has approved injectible vaccine and a nasal spray vaccine for the 2009 H1N1. In fact, the results have been better than good. Four manufacturers, CSL Ltd, MedImmune LLC, Novartis Vaccines and Diagnostics Ltd and Sanofi Pasteur Inc, have been given the go-ahead to manufacture them. A study carried in Australia and another one by the US National Institutes of Health indicated that healthy adults got protection from the flu with just one dose of vaccine, instead of two doses. People showed “robust” protection against the virus after about eight to 10 days of getting the vaccine shot, according to the FDA. The Centers for Disease Control and Prevention expects about 45 million doses to be available by mid-October.