Table 1.
Participant characteristics and their clinical signs and symptoms.
| Variable | Case, n = 197 | Control, n = 197 |
|---|---|---|
| Characteristics | ||
| Male:Female | 108:89 | 108:89 |
| Age (year), median (IQR) | 4 (0.41–65) | 4.1 (0.41–67) |
| Age group, n (%) | ||
| ≤ 2 years old | 58 (29.4) | 51 (25.9) |
| > 2 to ≤ 5 years old | 58 (29.4) | 65 (32.9) |
| > 5 to ≤ 15 years old | 59 (29.9) | 59 (29.9) |
| > 15 years old | 22 (11.2) | 22 (11.2) |
| Symptoms and signs | ||
| Number of days of fever, median (IQR) | 3 (2–5) | 0 |
| History of fever over the last 72 h, n (%) | 197 (100) | 0 |
| Tympanic temperature (ºC), median (IQR) | 38.0 (37.2–38.3) | 36.9 (36.7–37) |
| Rigors, n (%) | 20 (10.2) | 0 |
| Headache, n (%) | 57 (28.9) | 0 |
| Arthralgia, n (%) | 3 (1.5) | 1 (0.5) |
| Myalgia, n (%) | 28 (14.2) | 2 (1) |
| Back pain, n (%) | 3 (1.5) | 1 (0.5) |
| Nausea, n (%) | 34 (17.3) | 0 |
| Vomiting, n (%) | 68 (33.1) | 0 |
| Dysuria, n (%) | 3 (1.5) | 0 |
| Diarrhea, n (%) | 22 (11.2) | 0 |
| Abdominal pain, n (%) | 9 (4.6) | 0 |
| Shortness of breath, n (%) | 19 (9.6) | 0 |
| Difficulty breathing, n (%) | 30 (15.2) | 0 |
| Cough, n (%) | 167 (84.8) | 0 |
| Sputum, n (%) | 105 (53.3) | 0 |
| Sore throat, n (%) | 24 (12.2) | 0 |
| Runny nose, n (%) | 106 (53.8) | 4 (2) |
| Seizure, n (%) | 6 (3) | 0 |
| Respiratory rate/min, median (IQR) | 29 (20–30) | 26 (25–30) |
| Fast breathing€ (for children ≤ 5 years old), n (%) | 10/116 (8.6) | 0 |
| Abnormal chest auscultation, n (%) | 42 (21.3) | 0 |
| Pharyngeal erythema, n (%) | 143 (72.6) | 0 |
| Patient outcome | ||
| Pneumonia$ (for children ≤ 5 years old), n (%) | 10 (8.6%) | 0 |
| Severe pneumonia (for children ≤ 5 years old), n (%) | 6 (5.2%) | 0 |
| Duration of hospitalization (days), median (IQR) | 3 (3–5) | 0 |
| Death, n (%) | 0 | 0 |
| PCV-13* | ||
| Any PCV vaccination, n (%) | 49/100 (49.0) | 45/119 (37.8) |
| 1 dose, n | 3 | 4 |
| 2 doses, n | 1 | 1 |
| 3 doses, n | 44 | 29 |
€Fast breathing = aged 2–11 months: ≥ 50 breaths/min, aged 1–5 years: ≥ 40 breaths/min.
$Pneumonia and severe pneumonia were defined according to WHO criteria19. Children who presented with cough or difficulty breathing and had fast breathing or chest indrawing, were classified as having pneumonia. Children who presented with cough or difficulty breathing and had at least one of the following criteria were classified as severe pneumonia: oxygen saturation < 90%, while breathing room air, or central cyanosis; severe respiratory distress; signs of pneumonia with a general danger sign (inability to breastfeed or drink, lethargy or reduced level of consciousness, convulsions, vomiting).
*The number of doses were recorded if the vaccination card was seen by the study team. The pneumococcal conjugate vaccine 13 (PCV) was included in the Expanded Program on Immunization in Laos about 5 years before this study was conducted.