Table 5. Retrospective cohort study of risk factors for Middle East respiratory syndrome coronavirus infection acquired at King Fahd General Hospital, Jeddah, Saudi Arabia, March 2–May 10, 2014.
| Population or variable | No. cases | No. patient-days | Rate* | Rate ratio | p value |
|---|---|---|---|---|---|
| Emergency department, inpatient areas, dialysis unit† | 50 | 81,987 | 6.1 | ||
| Setting | |||||
| Emergency department | 22 | 34,897 | 6.3 | 1.2 | 0.64 |
| Inpatient areas | 17 | 26,186 | 6.5 | 1.2 | 0.60 |
| Dialysis unit | 11 | 20,904 | 5.3 | Referent | |
| Outbreak week: start date | |||||
| 1: March 2 | 1 | 8,609 | 1.2 | Referent | |
| 2: March 9 | 0 | 11,136 | 0.0 | Referent | |
| 3: March 16 | 2 | 11,437 | 1.7 | Referent | |
| 4: March 23 | 5 | 11,793 | 4.2 | 4.4 | 0.047 |
| 5: March 30 | 11 | 10,666 | 10.3 | 10.7 | <0.001 |
| 6: April 6 | 20 | 6,805 | 29.4 | 30.5 | <0.001 |
| 7: April 13 | 8 | 5,654 | 14.2 | 14.7 | <0.001 |
| 8: April 20 | 1 | 5,333 | 1.9 | 1.9 | 0.57 |
| 9: April 27 | 2 | 5,509 | 3.6 | 3.8 | 0.19 |
| 10: May 4 |
0 |
5,047 |
0.0 |
0.0 |
0.63 |
| Emergency department, hospital inpatient areas‡ | 39 | 61,083 | 6.4 | ||
| Nationality | |||||
| Saudi | 18 | 40,384 | 4.5 | Referent | |
| Non-Saudi | 21 | 20,698 | 10.1 | 2.3 | 0.01 |
| Sex | |||||
| F | 10 | 21,897 | 4.6 | Referent | |
| M | 29 | 39,151 | 7.4 | 1.6 | 0.18 |
| Age group, y | |||||
| 0–19 | 8 | 33,005 | 2.4 | Referent | |
| 20–39 | 10 | 16,888 | 5.9 | 2.4 | 0.064 |
| 40–59 | 18 | 9,400 | 19.1 | 7.9 | <0.001 |
| >60 | 3 | 1,725 | 17.4 | 7.2 | 0.016 |
*Per 10,000 patient-days. †For these analyses, cases were attributed to the setting or week that was most probable on the basis of incubation period (Tables 1, 2); p values do not reflect uncertainty caused by these attributions. ‡Denominator data for dialysis patients was not available; dialysis patients are not included in these analyses.