serologic evidence of human infection by francisella tularensis in the population of castilla y león (spain) prior to 1997. | prior to an outbreak in castilla y león in december 1997, tularaemia was practically non-existent in spain. in this paper we studied the prevalence of antibodies against francisella tularensis in a representative sample of the population (4825 people) from castilla y león (spain) in samples collected before this outbreak. antibodies against f. tularensis were detected in nine (0.19%) of the 4825 sera, with antibody titres ranging from 1/20 to 1/160. of these nine sera, one was positive in seroag ... | 2003 | 12628554 |