Table 1. Characteristics of patients infected with Salmonella enterica serovar Napoli and patients infected with the 5 most common other nontyphoidal serovars, Italy, 2011–2015*.
| Characteristic |
Serovar Napoli, no. (%) |
Other serovars, no. (%) |
Total |
p value |
aOR (95% CI) |
|---|---|---|---|---|---|
| Sex | |||||
| M | 525 (5.2) | 7,470 (73.8) | 10,119 | 0.001 | 1.17 (1.02–1.35) |
| F | 383 (4.3) | 6,521 (73.5) | 8,876 | 1 | |
| Unknown |
111 (4.5) |
1,757 (70.5) |
2,491 |
|
0.94 (0.75–1.18) |
| Age, y | |||||
| <1 | 69 (8.8) | 491 (62.6) | 784 | <0.001 | 3.05 (2.22–4.18) |
| 1–14 | 584 (5.6) | 8,378 (80.2) | 10,442 | 1.57 (1.28–1.92) | |
| 15–64 | 127 (3.1) | 2,667 (65.6) | 4,063 | 1 | |
| >65 | 195 (5.0) | 2,447 (63.3) | 3,863 | 1.76 (1.39–2.22) | |
| Unknown |
44 (1.9) |
1,765 (75.6) |
2,334 |
|
0.65 (0.45–0.92) |
| Geographic area | |||||
| North | 893 (5.1) | 12,708 (73.0) | 17,397 | <0.001 | 1.77 (1.43–2.20) |
| Central | 102 (3.0) | 2,540 (74.1) | 3,428 | 1 | |
| South |
24 (3.6) |
500 (86.4) |
661 |
|
1.63 (1.02–2.61) |
| Time of sampling | |||||
| Jan–Mar | 12 (0.3) | 3,623 (78.3) | 4,626 | <0.001 | 1 |
| Apr–Jun | 203 (4.4) | 3,356 (73.2) | 4,584 | 17.98 (10.02–32.26) | |
| Jul–Sep | 594 (8.8) | 4,622 (68.5) | 6,752 | 38.00 (21.41–67.44) | |
| Oct–Dec |
210 (3.8) |
4,147 (75.1) |
5,524 |
|
15.15 (8.45–27.17) |
| Period of sampling | |||||
| 2011–2013 | 643 (4.3) | 11,152 (73.9) | 15,081 | <0.001 | 1 |
| 2014–2015 |
376 (5.9) |
4,596 (71.8) |
6,405 |
|
1.4 (1.22–1.61) |
| Hospitalization | |||||
| Yes | 368 (4.9) | 5,453 (72.4) | 7,533 | 0.583 | ND |
| No | 358 (4.9) | 5,533 (75.1) | 7,367 | ND | |
| Unknown |
293 (4.4) |
4,762 (72.3) |
6,586 |
|
ND |
| Bacteremia | |||||
| Yes | 962 (4.6) | 15,527 (74.1) | 20,962 | <0.001 | ND |
| No | 57 (10.9) | 221 (42.2) | 524 | ND | |
| Unknown |
6 (4.9) |
75 (61.0) |
123 |
|
ND |
| Total | 1,019 (4.7) | 15,748 (73.3) | 21,486 | ND | ND |
*The 5 most common other serovars were the monophasic variant of Typhimurium, Typhimurium, Derby, Enteritidis, and Infantis. Hospitalization and bacteremia were not included in evaluation of risk factors because they were considered a consequence of the infection, rather than risk factors. aOR, adjusted odds ratio; ND, not determined.