Table 1.

Criteria used to define leptospirosis case patients for the different study groups

Country or stateCase definitiona
BarbadosCulture positive, a ≥4-fold rise in the MAT titer, or an MAT titer of ≥1:800 (8)
IndiaMAT titer of ≥1:80
KenyabMAT titer of ≥1:320
New ZealandCulture positive, a ≥4-fold rise in the MAT titer, or an MAT titer of ≥1:400
PhilippinescMAT titer of ≥1:400
Puerto Ricod≥4-fold rise in the MAT titer or an MAT titer of ≥1:320
SurinambMAT titer of ≥1:320
The NetherlandsCulture positive, a ≥4-fold rise in the MAT titer with a minimum titer of 1:160 for the second sample, or an MAT titer of ≥1:160 (5)
Thailandd≥4-fold rise in the MAT titer with a minimum titer of 1:320 for the second sample or an MAT titer of ≥1:320
HawaiieCulture positive or a ≥4-fold rise in the MAT titer and a minimum titer of 1:200 for the second samplef
RussiaMAT titer of ≥1:100 or a positive slide agglutination test (9)
Seychellesg≥4-fold rise in the MAT titer and a minimum titer of 1:100 for the second sampleh
  • a Patients with a clinical suspicion of leptospirosis but who did not meet the criteria as defined in Materials and Methods were considered noncase patients.

  • b The MAT was performed at the Royal Tropical Institute, Amsterdam, The Netherlands.

  • c The MAT and dipstick assay were performed at the University of Shizuoke, Shizuoke, Japan.

  • d The MAT and dipstick assay were performed at the Royal Tropical Institute.

  • e The MAT was performed at the Centers for Disease Control and Prevention, Atlanta, Ga.

  • f Patients with a minimum MAT titer of 1:200 but without a ≥4-fold rise between paired samples or with a minimum titer of 1:200 for single samples were considered probable leptospirosis patients.

  • g The MAT was performed at Institute Pasteur, Noumea, New Caledonia.

  • h Suspected leptospirosis patients with MAT titers of ≥1:400 but who did not show a ≥4-fold rise were considered probable leptospirosis patients.