Table 2. Description of the different data sets used in our study.
Columns include the category of data “Group” and “Sub-group”, the “Sample Size” of unique individuals, the “Selection Criteria” used for inclusion, the “Additional Details” regarding individuals included, the “Day 0”, i.e. the first day for which Leptospira infection related biomarkers were tracked in an individual, longitudinally monitored sea lion, and the “Length of Observation”, i.e. the period of time over which data were collected.
| Group | Sub-group | Sample Size | Selection Criteria | Additional Details | Day 0 | Length of Observation |
|---|---|---|---|---|---|---|
| Longi-tudinal | CLINICAL | 13 | Presented initially with clinical signs of severe renal compromise consistent with leptospirosis*. | Survived infection and released into wild 6–12 weeks after admission to rehabilitation center. | First day anti-Leptospira antibody titer detected (0–18 days of admission) | 6–12 weeks |
| SUB | 2 | Never showed clinical signs of leptospirosis. Admitted to rehabilitation center for treatment of other condition. Magnitude of the first detected anti-Leptospira antibody titers, and timing (October of a major Leptospira outbreak year in the wild sea lion population [32], suggest relatively recent Leptospira infection. | SUB1: No detectable anti-Leptospira antibodies initially, but seroconversion occurred (i.e. acquired anti-Leptospira antibodies) at some unknown point during rehabilitation, and in the absence of any observed clinical signs of leptospirosis. | First day anti-Leptospira antibody titer detected (log2 titer = 10 on 10/23/11, 15 months after admission). | 3 years | |
| SUB2: Moderately high anti-Leptospira antibody titer at admission. No clinical signs of leptospirosis. Released into wild 3 weeks after admission. Readmitted 3 months after initial admission, still no clinical signs of leptospirosis. | First day anti-Leptospira antibody titer detected ((log2 titer = 7 on 10/18/11, the day of admission) | |||||
| Cross-sectional | STRAND | 724 | All sea lions admitted to rehabilitation center for any cause, including leptospirosis. (i.e. not filtered by clinical signs) | N/A | 1 day | |
| WILD | 730 | Apparently healthy, free-ranging sea lions. | N/A | 1 day |
* Leptospirosis is the disease caused by infection with pathogenic species within the genus Leptospira.