Gram-negative species as percentages of all infant bacteraemia (Gram-negative and Gram-positive) in high-income and low-income/middle-income countries*
| High-income countries (n=55 studies) | Low-income/middle-income countries (n=90 studies) | |||
| Isolates, n | Proportion (95% CI) | Isolates, n | Proportion (95% CI) | |
| Escherichia coli | 5026 | 11.7% (9.40 to 14.4%) | 2758 | 7.67% (6.36 to 9.24%) |
| Klebsiella spp | 2401 | 3.17% (2.07 to 4.84%) | 5915 | 19.0% (16.3 to 22.1%) |
| Pseudomonas spp | 665 | 0.70% (0.04 to 1.09%) | 1127 | 2.53% (1.83 to 3.49%) |
| Enterobacter spp | 1395 | 0.63% (0.31 to 1.29%) | 918 | 1.18% (0.74 to 1.85%) |
| Serratia spp | 441 | 0.15% (0.06 to 0.37%) | 237 | 0.02% (0.00 to 0.09%) |
| Proteus spp | 34 | 0.01% (0.00 to 0.05%) | 134 | 0.04% (0.01 to 0.13%) |
| Salmonella spp | 61 | 0.00% (0.00 to 0.26%) | 215 | 0.00% (0.00 to 0.03%) |
| Citrobacter spp | 74 | 0.01% (0.00 to 0.06%) | 249 | 0.09% (0.04 to 0.23%) |
| Haemophilus spp | 272 | 0.02% (0.01 to 0.10%) | 38 | 0.00% (0.00 to 0.06%) |
| Neisseria spp | 19 | 0.00% (0.00 to 0.07%) | 13 | 0.00% (0.00 to 0.20%) |
| Acinetobacter spp | 394 | 0.14% (0.05 to 0.39%) | 1996 | 3.25% (2.41 to 4.37%) |
| Moraxella spp | 3 | 0.00% (0.00 to 3.05%) | 10 | 0.00% (0.00 to 3.11%) |
| Other species or unspecified Gram-negative | 868 | 0.42% (0.21 to 0.85%) | 978 | 0.43% (0.22 to 0.83%) |
*Estimates obtained by random-effects meta-analysis; see online supplemental file 4 for heterogeneity statistics.