| upper limit of normal titer for legionella pneumophila group 1 by indirect immunofluorescence and microagglutination tests in healthy population in italy. | the background prevalence of antibody to legionella pneumophila group 1 in two groups of healthy population of the areas of milano and roma, italy, was determined by testing single serum specimens from 530 blood donors by indirect immunofluorescence (ifa) test and by microagglutination (ma). the upper limit of normal (uln) titer was found to be 16 by ifa and 8 by ma. there was little difference in the prevalence of titers in the two geographic regions. of the 486 subjects from whom data were ava ... | 1985 | 3913451 |