Sero-survey for Legionella pneumophila antibodies--Singapore experience

One hundred and fifty blood bank donors were sero-surveyed for legionella antibodies by indirect immunofluorescence test using a polyvalent antigen group (1 to 4). 20% of the group surveyed had an antibody titre greater than or equal to 16 to the organism. This paper also reports a study on 166 hospitalised acute pneumonia patients. The sera from these patients were screened for L. pneumophila antibodies; 5 of the patients had significant antibody titre greater than or equal to 256 which is diagnostic of legionellosis.