Materials and methods
Eligible suspect cases of meningococcal meningitis underwent
a lumbar puncture to obtain a CSF sample. Most samples
underwent direct macroscopic and microscopic examinations
with WBC count followed by centrifugation, Gram
stain and Pastorex® agglutination test.
Samples were classified as negative by direct microscopy
if no bacteria were seen or if the presence of bacteria was
reported as rare with a WBC count 50/mm3. All samples with direct
microscopy results not fulfilling the criteria for either positive
or negative were classified as doubtful.