The St. Louis Post-Dispatch reports good news and bad news about the results of a pilot study on the Smallpox vaccine carried out right here at St. Louis University. The good news is that it would appear diluted vaccine does confer an immune response in people who were vaccinated previously (the general public hasn’t been vaccinated since 1972 in the US). Since there are only 15 million vaccine doses and more than 280 million Americans, that’s good news. Some scientists worried that the old vaccination would not confer enough of a response to require an even larger dose of the vaccine, let alone not allow a smaller dose to work. The bad news is that the old vaccination doesn’t appear to provide an immune response after more than 30 years – 10 years is apparently the accepted length of time, so for all of us who were once routinely inoculated and have that weird looking scar to prove it, we have no increased immunity to smallpox. A larger study is now being started to determine just how diluted the vaccine should be. If you’re worried and were once vaccinated, then call the Center for Vaccine Development at 314-977-6333 and see if you can sign up – although I warn you that people do have adverse responses to the vaccine (beyond the two weeks of a pus filled sore at the vaccination site).