Table 1.
Demographic and clinical characteristics of patients enrolled for severe respiratory and influenza-like illness surveillance and asymptomatic controls, South Africa, June 2012 – May 2016 (N = 12,922)
| Characteristic | Surveillance population | ||
|---|---|---|---|
| SRI n/N (%) N = 5634 | ILI n/N (%) N = 4933 | Controls n/N (%) N = 2355 | |
| Gender | |||
| Male | 2861/5626 (51) | 1757/4733 (37) | 774/2291 (34) |
| Female | 2765/5626 (49) | 2976/4733 (63) | 1517/2291 (66) |
| Race | |||
| Black | 5473/5604 (98) | 4723/4728 (100) | 2287/2292 (100) |
| Non-black | 131/5604 (2) | 5/4728 (0) | 5/2292 (0) |
| Age group (years) | |||
| < 1 | 1307/5618 (23) | 599/4921 (12) | 323/2352 (14) |
| 1–4 | 764/5618 (14) | 1019/4921 (21) | 464/2352 (20) |
| 5–14 | 168/5618 (3) | 727/4921 (15) | 520/2352 (22) |
| 15–24 | 276/5618 (5) | 649/4921 (13) | 191/2352 (8) |
| 25–44 | 1756/5618 (31) | 1388/4921 (28) | 371/2352 (16) |
| 45–64 | 1051/5618 (19) | 460/4921 (9) | 337/2352 (14) |
| ≥ 65 | 296/5618 (5) | 79/4921 (2) | 146/2352 (6) |
| Underlying illness* | |||
| No | 5023/5627 (89) | 4484/4723 (95) | 2172/2290 (95) |
| Yes | 604/5627 (11) | 239/4723 (5) | 118/2290 (5) |
| HIV status | |||
| Uninfected | 2577/5308 (49) | 3253/4451 (73) | 1314/2263 (58) |
| Infected | 2731/5308 (51) | 1198/4451 (27) | 949/2263 (42) |
| Hospital/Clinic | |||
| Edendale | 2507/5634 (45) | N/A | N/A |
| KTHC | 3127/5634 (56) | N/A | N/A |
| Edendale Gateway | N/A | 3655/4933 (74) | 1041/2355 (44) |
| Jouberton Clinic | N/A | 1278/4933 (26) | 1314/2355 (56) |
SRI = Severe respiratory illness; ILI = Influenza-like illness; N/A = Not applicable; KTHC = Klerksdorp Tshepong hospital complex
*Patients with previously diagnosed chronic conditions including asthma, chronic lung diseases, cirrhosis/liver failure, chronic renal failure, heart failure, valvular heart disease, coronary heart disease, immunosuppressive therapy, splenectomy, diabetes, burns, kwashiorkor/marasmus, nephrotic syndrome, spinal cord injury, seizure disorder, emphysema, or cancer. All percentages are rounded off