Volume 15, Number 5—May 2009
Research
Seroprevalence of Antibodies to Avian Influenza Virus A (H5N1) among Residents of Villages with Human Cases, Thailand, 20051
Table 1
Characteristics of the study population, overall and by method of selection, Thailand, 2005
Characteristic | Random sample (n = 131), no. (%) | Convenience sample (n = 770), no. (%) | p value | Total sample (N = 901), no. (%) |
---|---|---|---|---|
Age group, y | 0.30 | |||
1–14 | 19 (14.5) | 178 (23.1) | 197 (21.9) | |
15–29 | 14 (10.7) | 99 (12.9) | 113 (12.5) | |
30–44 | 37 (28.2) | 177 (23.0) | 214 (23.8) | |
45–59 | 32 (24.4) | 175 (22.7) | 207 (22.9) | |
60–74 | 24 (18.3) | 109 (14.2) | 133 (14.8) | |
75–89 | 4 (3.1) | 28 (3.6) | 32 (3.6) | |
90–104 |
1 (0.8) |
4 (0.5) |
5 (0.5) |
|
Occupation | 0.04 | |||
Plant farmer | 59 (45.0) | 236 (30.6) | 295 (32.7) | |
Animal farmer | 3 (2.3) | 11 (1.4) | 14 (1.6) | |
Farmer (plant and animal) | 2 (1.5) | 7 (1.0) | 9 (0.10) | |
Merchant | 2 (1.5) | 13 (1.7) | 15 (1.7) | |
Government officer | 0 | 3 (0.4) | 3 (0.4) | |
Other (employee, housekeeper) | 42 (32.1) | 346 (44.9) | 388 (43.0) | |
Missing |
23 (17.6) |
154 (20.0) |
177 (19.6) |
|
Sex | 0.70 | |||
Male | 58 (44.3) | 324 (42.1) | 382 (42.4) | |
Female |
73 (55.7) |
446 (57.9) |
519 (57.6) |
|
Risk factors | 0.60 | |||
Direct or close contact with backyard poultry (including chickens) | 89 (67.9) | 525 (68.2) | 614 (68.1) | |
Direct or close contact with backyard chickens | 86 (65.6) | 519 (67.4) | 605 (67.1) | |
Direct or close contact with dead/sick chicken | 36 (27.5) | 196 (25.5) | 232 (25.7) | |
Close contact with a person with a confirmed case
of avian influenza A |
13 (9.9) |
51 (6.6) |
64 (7.1) |
|
Acute respiratory symptoms* | 0.31 | |||
Symptoms | 12 (9.2) | 98 (12.7) | 110 (12.2) | |
No symptoms |
119 (90.8) |
672 (87.3) |
791 (87.89) |
|
Influenza-like illness† | 0.39 | |||
Symptoms | 7 (5.3) | 61 (7.9) | 68 (7.5) | |
No symptoms | 124 (94.7) | 709 (92.1) | 833 (92.5) |
*Acute respiratory symptoms were rhinorrhea, cough, sore throat, or dyspnea.
†Influenza-like illness was defined as a temperature >38.0°C in conjunction with any of the following: rhinorrhea, cough, sore throat, or dyspnea.
1Preliminary findings from this study were presented on June 18, 2007, at the Options for the Control of Influenza Conference VI, Toronto, Ontario, Canada.