TABLE 1.

Detection of anti-recombinant LigB IgG and IgM antibodies in sera from leptospirosis patients and control subject groups as determined by immunoblotting

GroupNo. of samples testedrLigB seroreactivity (no. positive reactions [%]) to:
IgMIgG
Confirmed leptospirosis cases
    Acute phasea9587 (92)81 (85)
    Acute phase, IgM ELISA negativeb4023 (57)21 (52)
    Convalescent phasea9569 (73)93 (98)
Healthy control individualsc
    Region of nonendemicity400 (0)0 (0)
    Region of endemicity502 (4)3 (6)
    High-risk region of endemicity756 (8)9 (12)
Patient control groups
    Dengue301 (3)0 (0)
    Hepatitis303 (10)9 (30)
    Lyme disease302 (7)4 (13)
    VDRL test positive303 (10)6 (20)
  • a Paired serum samples from 95 laboratory-confirmed leptospirosis patients were evaluated. Acute and convalescent patients had sample collection means of 9.0 (±3.8) days and 35.3 (±26.8) days, respectively, after onset of symptoms.

  • b Acute-phase samples from 40 confirmed leptospirosis patients, which had negative reactions in the whole-Leptospira-based IgM ELISA, were tested.

  • c Samples were obtained from a serum bank for healthy individuals from northern California (region of nonendemicity), from randomly-selected subjects participating in a citywide serosurvey in Salvador, Brazil (region of endemicity), and from neighbors of leptospirosis cases residing in slum communities in Salvador, Brazil (high-risk region of endemicity).