Table 3.
Factors associated with clinical severity (MEWS > 4) in adults with SARI, Blantyre, Malawi, 2011–2013
| Characteristic | Number of cases with clinical severity N (%) | Univariable* | Multivariable*† | ||
|---|---|---|---|---|---|
| OR (95% CI) | P value | OR (95% CI) | P value | ||
| Gender | |||||
| Male | 105/489 (21.5) | Ref | – | Ref | – |
| Female | 133/636 (20.9) | 0.97 (0.72–1.29) | 0.82 | 0.93 (0.69–1.27) | 0.65 |
| Age group (years) | |||||
| 15–24 | 46/231 (19.9) | Ref | – | Ref | – |
| 25–34 | 87/419 (20.8) | 1.05 (0.71–1.57) | – | 0.82 (0.53–1.26) | – |
| ≥ 35 | 105/476 (22.1) | 1.11 (0.81–1.51) | 0.80 | 0.96 (0.63–1.46) | 0.55 |
| Year of surveillance | |||||
| 2011 | 78/251 (31.1) | 2.07 (1.46–2.94) | 0.001 | 2.31 (1.59–3.36) | < 0.001 |
| 2012 | 69/366 (18.9) | 1.07 (0.75–1.51) | – | 1.19 (0.82–1.72) | – |
| 2013 | 91/509 (17.9) | Ref | – | Ref | – |
| Season | |||||
| December–March (hot and rainy) | 125/348 (35.9) | 4.32 (2.80–6.67) | – | 4.98 (3.17–7.81) | < 0.001 |
| April–August (cool and dry) | 82/508 (16.1) | 1.48 (0.95–2.31) | – | 1.66 (1.05–2.63) | – |
| September–November (hot and dry) | 31/270 (11.5) | Ref | – | Ref | – |
| HIV status | |||||
| Negative | 91/551 (16.5) | Ref | – | Ref | – |
| Positive | 143/558 (25.6) | 1.74 (1.30–2.34) | < 0.001 | 1.86 (1.35–2.56) | < 0.001 |
| Medical history | |||||
| Pregnancy–No | 131/618 (21.2) | Ref | – | – | – |
| Yes | 2/19 (10.5) | 0.44 (0.10–1.92) | 0.27 | – | – |
| Recent antibiotics–No | 134/548 (24.5) | Ref | – | – | – |
| Yes | 101/483 (20.9) | 0.82 (0.61–1.10) | 0.19 | – | – |
| Current smoker—no | 224/946 (23.7) | Ref | – | – | – |
| Yes | 14/102 (13.7) | 0.25 (0.06–1.04) | 0.06 | – | – |
| Malaria RDT—Negative | 213/883 (24.1) | Ref | – | – | – |
| Positive | 6/28 (21.4) | 0.86 (0.34–2.14) | 0.74 | – | – |
| Influenza—negative | 198/962 (20.6) | Ref | – | – | – |
| Positive | 40/163 (24.5) | 1.25 (0.85–1.85) | 0.25 | – | – |
| Viral co-infections | |||||
| No | 198/976 (20.3) | Ref | – | – | – |
| Yes | 40/150 (26.7) | 1.37 (0.93–2.03) | 0.11 | – | – |
| Other respiratory viruses | |||||
| Adenovirus—negative | 228/1,076 (21.2) | Ref | – | – | – |
| Positive | 10/47 (21.3) | 1.01 (0.49–2.05) | 0.99 | – | – |
| Bocavirus—negative | 232/1,099 (21.1) | Ref | – | – | – |
| Positive | 6/24 (25.0) | 1.25 (0.49–3.17) | 0.65 | – | – |
| Coronavirus | |||||
| OC43—negative | 225/1,074 (21.0) | Ref | – | – | – |
| Positive | 13/49 (26.5) | 1.36 (0.71–2.61) | 0.35 | – | – |
| NL63—negative | 227/1,086 (20.9) | Ref | – | – | – |
| Positive | 11/37 (29.7) | 1.60 (0.78–3.29) | 0.20 | – | – |
| 229E—negative | 227/1,088 (20.9) | Ref | – | – | – |
| Positive | 11/35 (31.4) | 1.74 (0.84–3.60) | 0.14 | – | – |
| HKU1—negative | 220/1,063 (20.7) | Ref | – | – | – |
| Positive | 7/40 (17.5) | 0.81 (0.35–1.86) | 0.62 | – | – |
| Enterovirus—negative | 236/1,091 (21.6) | Ref | – | – | – |
| Positive | 2/32 (6.3) | 0.24 (0.06–1.02) | 0.05 | – | – |
| hMPV—negative | 224/1,089 (20.6) | Ref | – | – | – |
| Positive | 14/34 (41.2) | 2.70 (1.34–5.44) | 0.005 | – | – |
| Parainfluenza virus | |||||
| 1—Negative | 230/1,095 (21.0) | Ref | – | – | – |
| Positive | 8/28 (28.6) | 1.50 (0.65–3.46) | 0.34 | – | – |
| 2—Negative | 231/1,105 (20.9) | Ref | – | – | – |
| Positive | 7/18 (38.9) | 2.40 (0.92–6.28) | 0.07 | – | – |
| 3—Negative | 234/1,100 (21.3) | Ref | – | – | – |
| Positive | 4/23 (17.4) | 0.78 (0.26–2.31) | 0.65 | – | – |
| 4—Negative | 233/1,095 (21.3) | Ref | – | – | – |
| Positive | 5/28 (17.9) | 0.80 (0.30–2.14) | 0.66 | – | – |
| RSV—negative | 226/1,075 (21.0) | Ref | – | – | – |
| Positive | 12/47 (25.0) | 1.25 (0.64–2.45) | 0.51 | – | – |
| Rhinovirus—negative | 201/974 (20.6) | Ref | – | – | – |
| Positive | 37/149 (24.8) | 1.27 (0.85–1.90) | 0.24 | – | – |
CI = confidence interval; HIV = human immunodeficiency virus; MEWS = modified early warning score; OR = odds ratio; RDT = rapid diagnostic test; RSV = respiratory syncytial virus; SARI = severe acute respiratory infection.
*
Logistic regression.
†
Backward stepwise approach, including a priori confounders (age, gender, HIV status, and year of surveillance) and all variables with P < 0.20 in univariate analysis.