Table 1. Clinical manifestations and laboratory test results for scrub typhus in 10 RTA soldiers who trained in Si Racha District, Chonburi Province, Thailand, 2013*.
| ID |
Age, y |
Clinical signs and symptoms | Symptom onset to collection, d† |
Test results for O. tsutsugamushi, IgM/IgG‡ | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Fever |
Eschar |
Headache |
Chill |
Eye pain |
IFA |
|
Dot-ELISA |
|||||||
| 1 |
2 |
3 |
1 |
2 |
3 |
|||||||||
| P01 | 25 | + | + | + | + | + | 3 | Neg/Neg | 1,600/1,600 | 1,600/1,600 | −/+ | +/+ | +/+ | |
| P02 | 22 | + | − | + | + | − | 5 | 200/50 | 1,600/50 | 1,600/50 | +/+ | +/+ | +/+ | |
| P03 | 25 | + | + | + | + | − | 5 | 200/200 | 1,600/3,200 | 1,600/3,200 | +/+ | +/+ | +/+ | |
| P04 | 23 | + | − | + | + | − | 5 | 200/100 | 3,200/800 | 3,200/800 | +/+ | +/+ | +/+ | |
| P05 | 21 | + | − | + | + | − | 5 | 200/100 | 3,200/800 | 3,200/800 | +/+ | +/+ | +/+ | |
| P06 | 21 | + | − | + | + | + | 5 | 800/100 | 6,400/3,200 | 6,400/3,200 | +/+ | +/+ | +/+ | |
| P07 | 21 | + | − | + | − | − | 8 | ND | 1,600/100 | 6,400/6,400 | ND | +/+ | +/+ | |
| P08 | 22 | + | − | − | + | − | 9 | ND | 800/50 | 800/50 | ND | +/+ | +/+ | |
| P09 | 45 | + | − | + | − | − | 23 | ND | ND | 1,600/1,600 | ND | ND | +/+ | |
| P10 | 21 | + | + | + | + | + | 12 | ND | ND | 3,200/3,200 | ND | ND | +/+ | |
*ID, patient identification number; IFA, indirect fluorescence antibody assay; ND, not determined; + positive; –, negative. †Time from onset of signs and symptoms to first blood collection. ‡Karp, Kato, and Gilliam genotypes. Tests were performed on September 27 (round 1), October 4 (round 2), and October 7 (round 3). Positivity cutoff titer for initial screening was 1:50 and the diagnostic criteria were established as a >4-fold increase in the titer of IgM or IgG in paired serum samples. If only 1 serum sample was available, titer of 1:50 to <1:400 was determined as recent or previous infection and titer >1:400 as active infection.