Table 2.
Variables | Primary infection (N = 67a) | Secondary infection (N = 283) | P | Children 5–15 years (N = 132a) | Adult ≥15 years (N = 218) | P |
---|---|---|---|---|---|---|
Age (yr)b | 12.2 (5.3–51.7) | 20.6 (5.5–73.6) | <0.001 | 11.2 (5.3–15.0) | 28.1 (15.5–73.7) | |
Male/female | 44/23 | 180/103 | 80/52 | 144/74 | ||
Body temperature (°C)b | 38.9 (38.0–39.9) | 39.0 (38.0–42.0) | 39.0 (38.0–42.0) | 39.0 (38.0–40.0) | ||
Pulse pressure (mmHg)b | 30.0 (30.0–60.0) | 40.0 (20.0–60.0) | <0.001 | 30.0 (20.0–55.0) | 40.0 (20.0–60.0) | <0.001 |
Heart rate (beats/min)b | 90.0 (70.0–130.0) | 90.0 (66.0–130.0) | 95.0 (76.0–130.0) | 90.0 (66.0–120.0) | <0.001 | |
Symptoms, (%) | ||||||
Headache | 91.0 | 94.7 | 92.4 | 95.0 | ||
Myalgia | 29.9 | 52.7 | 0.001 | 25.8 | 61.9 | <0.001 |
Sore throat | 32.8 | 42.4 | 44.7 | 38.1 | ||
Backache | 20.9 | 19.1 | 6.1 | 27.5 | <0.001 | |
Nausea | 20.9 | 23.7 | 14.4 | 28.4 | 0.003 | |
Cough | 28.4 | 33.6 | 31.8 | 33.0 | ||
Arthralgia | 16.4 | 17.7 | 10.6 | 21.6 | 0.009 | |
Gastrointestinal symptoms | 25.4 | 13.1 | 0.022 | 12.1 | 17.4 | |
Findings at physical examination, (%) | ||||||
Pallor | 19.4 | 17.3 | 12.1 | 21.1 | 0.043 | |
Dehydration | 11.9 | 13.1 | 13.6 | 12.4 | ||
Pharyngitis | 40.3 | 49.5 | 48.5 | 47.2 | ||
Lymph nodes | 0.0 | 0.7 | 1.5 | 0.0 | ||
Rash | 0.0 | 2.5 | 0.0 | 3.2 | ||
Bruises | 6.0 | 4.2 | 0.8 | 6.9 | 0.007 |
One child (age = 4.2 years) was excluded from analysis.
Median (range); differences between groups were analyzed with Mann–Whitney tests. Fisher's exact test was used in all dichotomous data. Gastrointestinal symptoms: abdominal pain, diarrhea and constipation.