Table 2.
Hazard ratios of risk factors for developing total RSV‐LRTI and total severe RSV‐LRTI in children aged 2‐59 mo
| Risk factors | Child‐years (n = 4571) | Total RSV‐LRTI (n = 284) | Total severe RSV‐LRTI (n = 101) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | IR | HR | 95% CI | aHRa | 95% CI | n | IR | HR | 95% CI | aHRb | 95% CI | ||
| Age in months | |||||||||||||
| 2‐5 | 242 | 46 | 190.1 | 8.3** | 5.6‐12.4 | 8.5** | 5.7‐12.7 | 16 | 66.1 | 11.8** | 5.5‐25.4 | 11.3** | 5.2‐24.3 |
| 6‐11 | 421 | 36 | 85.5 | 3.7** | 2.4‐5.8 | 3.8** | 2.5‐5.9 | 19 | 45.1 | 8.1** | 3.9‐16.9 | 7.5** | 3.6‐16.0 |
| 12‐23 | 950 | 118 | 124.2 | 5.4** | 3.9‐7.6 | 5.4** | 3.8‐7.5 | 48 | 50.5 | 9.1** | 4.7‐17.4 | 8.3** | 4.3‐16.1 |
| 24‐35 | 986 | 39 | 39.6 | 1.7** | 1.1‐2.7 | 1.7** | 1.1‐2.7 | 7 | 7.1 | 1.3 | 0.5‐3.3 | 1.2 | 0.5‐3.2 |
| 36‐59 | 1972 | 45 | 22.8 | Ref | Ref | 11 | 5.6 | Ref | Ref | ||||
| Sex | |||||||||||||
| Male | 2395 | 150 | 62.6 | Ref | Ref | 60 | 25.1 | Ref | Ref | ||||
| Female | 2177 | 134 | 61.6 | 1.0 | 0.8‐1.2 | 1.0 | 0.8‐1.3 | 41 | 18.8 | 0.8 | 0.5‐1.1 | 0.8 | 0.5‐1.2 |
| Place of living (municipality) | |||||||||||||
| Caibiran | 2168 | 196 | 90.4 | 2.5** | 1.9‐3.2 | 2.5** | 2.0‐3.2 | 64 | 29.5 | 1.9** | 1.3‐2.9 | 1.9** | 1.3‐2.8 |
| Kawayan | 2404 | 88 | 36.6 | Ref | Ref | 37 | 15.4 | Ref | Ref | ||||
| Gestational age | |||||||||||||
| ≥36 wk | 4145 | 268 | 64.7 | Ref | Ref | 97 | 23.4 | Ref | Ref | ||||
| <36 wk | 51 | 3 | 58.8 | 0.9 | 0.3‐2.7 | 1.0 | 0.3‐3.0 | 2 | 39.2 | 1.7 | 0.4‐6.5 | 1.8 | 0.4‐7.2 |
| Unknown | 375 | 13 | 34.7 | 0.5** | 0.3‐0.9 | 0.8 | 0.4‐1.5 | 2 | 5.3 | 0.2** | 0.1‐0.9 | 0.4 | 0.1‐1.8 |
| Birthweight (g) | |||||||||||||
| ≥ 2500 | 3053 | 204 | 66.8 | Ref | Ref | 71 | 23.3 | Ref | Ref | ||||
| <2500 | 518 | 30 | 57.9 | 0.9 | 0.6‐1.3 | 0.9 | 0.6‐1.4 | 12 | 23.2 | 1.0 | 0.5‐1.8 | 1.1 | 0.6‐2.0 |
| Unknown | 1000 | 50 | 50.0 | 0.7* | 0.5‐1.0 | 1.0 | 0.7‐1.4 | 18 | 18.0 | 0.8 | 0.5‐1.3 | 1.3 | 0.8‐2.3 |
| No. of family member (persons) | |||||||||||||
| <7 | 2385 | 139 | 58.3 | Ref | Ref | 51 | 21.4 | Ref | Ref | ||||
| ≥7 | 2187 | 145 | 66.3 | 1.1 | 0.9‐1.4 | 1.1 | 0.8‐1.3 | 50 | 22.9 | 1.1 | 0.7‐1.6 | 0.8 | 0.5‐1.2 |
| Having smoker in the same HH | |||||||||||||
| No | 1916 | 122 | 63.7 | Ref | Ref | 46 | 24.0 | Ref | Ref | ||||
| Yes | 2656 | 162 | 61.0 | 1.0 | 0.8‐1.2 | 0.9 | 0.7‐1.1 | 55 | 20.7 | 0.9 | 0.6‐1.3 | 0.7 | 0.5‐1.1 |
| Birth order | |||||||||||||
| 1st | 1489 | 89 | 59.8 | Ref | Ref | 27 | 18.1 | Ref | Ref | ||||
| 2nd or 3rd | 1821 | 105 | 57.7 | 1.0 | 0.7‐1.3 | 0.9 | 0.7‐1.2 | 36 | 19.8 | 1.1 | 0.7‐1.8 | 1.1 | 0.6‐1.9 |
| >3rd | 1262 | 90 | 71.3 | 1.2 | 0.9‐1.6 | 1.0 | 0.7‐1.3 | 38 | 30.1 | 1.7** | 1.0‐2.7 | 1.5 | 0.9‐2.7 |
| Socioeconomic status (points) | |||||||||||||
| ≥30 | 2309 | 139 | 60.2 | Ref | Ref | 49 | 21.2 | Ref | Ref | ||||
| <30 | 2262 | 145 | 64.1 | 1.1 | 0.8‐1.3 | 1.0 | 0.8‐1.3 | 52 | 23.0 | 1.1 | 0.7‐1.6 | 0.9 | 0.6‐1.4 |
| Educational level of caregiver (y) | |||||||||||||
| ≤6 | 1237 | 68 | 55.0 | 1.3 | 0.8‐1.9 | 1.5** | 1.0‐2.3 | 25 | 20.2 | 1.4 | 0.7‐2.8 | 1.3 | 0.6‐2.8 |
| 7‐9 | 1320 | 91 | 68.9 | 1.6** | 1.1‐2.3 | 1.7** | 1.2‐2.5 | 25 | 18.9 | 1.3 | 0.7‐2.6 | 1.2 | 0.6‐2.4 |
| 10 | 1172 | 88 | 75.1 | 1.7** | 1.2‐2.5 | 1.7** | 1.2‐2.5 | 39 | 33.3 | 2.3** | 1.2‐4.4 | 2.1** | 1.1‐4.1 |
| ≥11 | 843 | 37 | 43.9 | Ref | Ref | 12 | 14.2 | Ref | Ref | ||||
| Educational level of father (y) | |||||||||||||
| ≤6 | 1342 | 79 | 58.9 | 0.9 | 0.6‐1.3 | 0.8 | 0.5‐1.1 | 37 | 27.6 | 2.4* | 1.0‐6.1 | 2.2 | 0.8‐5.7 |
| 7‐9 | 748 | 49 | 65.5 | 1.0 | 0.6‐1.5 | 0.8 | 0.5‐1.3 | 16 | 21.4 | 1.9 | 0.7‐5.0 | 1.7 | 0.6‐4.8 |
| 10 | 502 | 25 | 49.8 | 0.8 | 0.4‐1.3 | 0.6* | 0.4‐1.0 | 8 | 15.9 | 1.4 | 0.5‐4.2 | 1.2 | 0.4‐3.6 |
| ≥11 | 437 | 29 | 66.4 | Ref | Ref | 5 | 11.4 | Ref | Ref | ||||
| Unknown | 1543 | 102 | 66.1 | 1.0 | 0.7‐1.5 | 0.9 | 0.6‐1.3 | 35 | 22.7 | 2.0 | 0.8‐5.0 | 2.0 | 0.7‐5.3 |
| House wall material | |||||||||||||
| Light material | 1436 | 99 | 68.9 | Ref | Ref | 38 | 26.5 | Ref | Ref | ||||
| Strong material | 3136 | 185 | 59.0 | 0.9 | 0.7‐1.1 | 1.0 | 0.8‐1.3 | 63 | 20.1 | 0.8 | 0.5‐1.1 | 0.9 | 0.6‐1.3 |
| Kitchen location | |||||||||||||
| Outside of household | 1583 | 99 | 62.5 | Ref | Ref | 38 | 24.0 | Ref | Ref | ||||
| Inside of household | 2988 | 185 | 61.9 | 1.0 | 0.8‐1.3 | 0.9 | 0.7‐1.2 | 63 | 21.1 | 0.9 | 0.6‐1.3 | 0.8 | 0.6‐1.2 |
| Fuel type for cooking | |||||||||||||
| Electricity, LPG or kerosene | 308 | 17 | 55.2 | Ref | Ref | 5 | 16.2 | Ref | Ref | ||||
| Solid fuel | 4263 | 267 | 62.6 | 1.1 | 0.7‐1.9 | 1.0 | 0.6‐1.8 | 96 | 22.5 | 1.4 | 0.6‐3.4 | 1.1 | 0.4‐2.9 |
| Treatment of drinking water | |||||||||||||
| Nothing | 2070 | 136 | 65.7 | Ref | Ref | 44 | 21.3 | Ref | Ref | ||||
| Boil or bleach | 809 | 50 | 61.8 | 0.9 | 0.7‐1.3 | 1.1 | 0.8‐1.4 | 22 | 27.2 | 1.3 | 0.8‐2.1 | 1.3 | 0.8‐2.2 |
| Buying filtrated water | 1675 | 98 | 58.5 | 0.9 | 0.7‐1.2 | 1.0 | 0.8‐1.3 | 35 | 20.9 | 1.0 | 0.6‐1.5 | 1.0 | 0.7‐1.6 |
| Others | 17 | 0 | 0.0 | NA | NA | 0 | 0.0 | NA | NA | ||||
| Owning private toilet | |||||||||||||
| No | 1983 | 115 | 58.0 | Ref | Ref | 40 | 20.2 | Ref | Ref | ||||
| Yes | 2589 | 169 | 65.3 | 1.1 | 0.9‐1.4 | 1.3* | 1.0‐1.6 | 61 | 23.6 | 1.2 | 0.8‐1.7 | 1.4 | 0.9‐2.1 |
| # of other children <6 yr in HH | |||||||||||||
| None | 1575 | 87 | 55.2 | Ref | Ref | 28 | 17.8 | Ref | Ref | ||||
| 1 | 1843 | 133 | 72.2 | 1.3* | 1.0‐1.7 | 1.1 | 0.9‐1.5 | 53 | 28.8 | 1.6** | 1.0‐2.5 | 1.3 | 0.8‐2.2 |
| ≥ 2 | 1154 | 64 | 55.5 | 1.0 | 0.7‐1.4 | 0.8 | 0.6‐1.1 | 20 | 17.3 | 1.0 | 0.6‐1.7 | 0.7 | 0.4‐1.3 |
| # of other children 6‐14 yr in HH | |||||||||||||
| None | 1702 | 104 | 61.1 | Ref | Ref | 35 | 20.6 | Ref | Ref | ||||
| 1‐2 | 2006 | 116 | 57.8 | 0.9 | 0.7‐1.2 | 1.0 | 0.8‐1.3 | 42 | 20.9 | 1.0 | 0.7‐1.6 | 1.0 | 0.6‐1.6 |
| ≥ 3 | 864 | 64 | 74.1 | 1.2 | 0.9‐1.7 | 1.2 | 0.9‐1.6 | 24 | 27.8 | 1.4 | 0.8‐2.2 | 1.1 | 0.6‐2.1 |
| Breastfeeding statusc | |||||||||||||
| Non‐exclusive breastfeeding | 47 | 9 | 191.5 | Ref | Ref | 6 | 127.7 | Ref | Ref | ||||
| Exclusive breastfeeding | 70 | 8 | 114.3 | 0.6 | 0.2‐1.6 | 0.6 | 0.2‐1.6 | 2 | 28.6 | 0.2* | 0.0‐1.1 | 0.2* | 0.0‐1.2 |
| Unknown | 126 | 29 | 230.2 | 1.2 | 0.6‐2.6 | 1.1 | 0.5‐2.3 | 8 | 63.5 | 0.5 | 0.2‐1.5 | 0.5 | 0.2‐1.3 |
aHR, adjusted hazard ratio; HH, household; HR, hazard ratio; IR, incidence rate; LRTI, lower respiratory tract illness; RSV, respiratory syncytial virus.
Total RSV‐LRTI consists of RSV‐LRTI, severe RSV‐LRTI and very severe RSV‐LRTI. Total severe RSV‐LRTI consists of severe RSV‐LRTI and very severe RSV‐LRTI. Caregiver is the person that takes care of the child, knows best about the child and makes decisions for the best interest of the child. Solid fuel contains wood, charcoal, paper, etc
Adjusted for age group, sex, place of living, gestational age, birthweight, educational level of caregiver and number of other children <6 y in household.
Adjusted for age group, sex, place of living, gestational age, birth order, educational level of caregiver and father and number of other children <6 y in household.
Hazard ratio for breastfeeding status was adjusted for age group, sex, place of living and educational level of caregiver and calculated using subset data for 2‒6 y old.
P < 0.1.
P < 0.05.