Volume 9, Number 4—April 2003
Research
Dengue Fever in Travelers to the Tropics, 1998 and 1999
Heidi Lindbäck*†, Johan Lindbäck†, Anders Tegnell†, Ragnhild Janzon†, Sirkka Vene†, and Karl Ekdahl†
Table 3
Odds ratios for diagnosis of dengue fever, calculated for possible risk factors
| Risk factor | Ratio in cases | Ratio in controls | Odds ratio | 95% CIa |
|---|---|---|---|---|
| Geographic area |
||||
| India with neighbors |
7/105 |
7/292 |
2.91 |
0.89 to 9.50 |
| Malay Peninsula |
79/105 |
111/292 |
4.95 |
2.92 to 8.46 |
| China |
0/105 |
17/292 |
0.00 |
0.00 to 0.65 |
| The rest of Asia |
3/105 |
15/292 |
0.54 |
0.10 to 1.98 |
| Carribean |
4/105 |
40/292 |
0.25 |
0.06 to 0.72 |
| Central America |
3/105 |
17/292 |
0.48 |
0.11 to 1.77 |
| South America |
1/105 |
21/292 |
0.12 |
0.00 to 0.79 |
| West Africa |
0/105 |
6/292 |
0.00 |
0.00 to 2.60 |
| East Africa |
1/105 |
4/292 |
0.69 |
0.01 to 7.11 |
| South Africa |
0/105 |
11/292 |
0.00 |
0.00 to 1.09 |
| Australia and Pacific Islands |
7/105 |
43/292 |
0.41 |
0.15 to 0.97 |
| Age groups (y) |
||||
| 0–14 |
2/107 |
14/292 |
0.38 |
0.04 to 1.69 |
| 15–29 |
58/107 |
82/292 |
3.03 |
1.87 to 4.92 |
| 30–44 |
33/107 |
79/292 |
1.20 |
0.72 to 2.01 |
| >45 |
14/107 |
117/292 |
0.23 |
0.12 to 0.43 |
| Sex |
||||
| Male |
54/107 |
154/292 |
0.91 |
0.57 to 1.46 |
| Length of travel (nights) |
||||
| 0–10 |
0/74 |
68/292 |
0.00 |
0.00 to 0.17 |
| 11–17 |
16/74 |
149/292 |
0.26 |
0.14 to 0.50 |
| 18–24 |
13/74 |
31/292 |
1.79 |
0.83 to 3.82 |
| >25 | 45/74 | 44/292 | 8.75 | 4.79 to 16.06 |
aCI, confidence interval.
