Volume 32, Number 4—April 2026
Research
Respirable Aerosol Production and Reduction of Avian Influenza Transmission Risk during Chicken Processing, Bangladesh
Table
PM2.5 mass concentration across combined sensor positions during experiments of chicken slaughtering and defeathering methods in study of respirable aerosol production and reduction of avian influenza transmission risk during chicken processing, Bangladesh Livestock Research Institute, Savar, Dhaka, 2020*
| Method | Mean PM2.5 mass concentration during baseline, µg/m3 (min–max)† | Mean PM2.5, µg/m3 (SD) | PM2.5 mass concentration difference from referent, µg/m3 | Percentage of reduced PM2.5 mass concentration (95% CI) | p value‡ |
|---|---|---|---|---|---|
| Single chicken slaughtering, n = 27 | |||||
| Open barrel without lid | 11.1 (10–18) | 49.6 (25.4) | Referent | – | – |
| Barrel covered with solid lid | 10.1 (10–12) | 14.1 (5.5) | –35.5 | –71.6 (–77.7 to –63.9) | <0.001 |
| Barrel covered with star-cut lid | 10 (10–10) | 13.3 (5.2) | –36.2 | –73.1 (–78.9 to –65.8) | <0.001 |
| Small cone | 10.3 (10–16) | 57.4 (47.7) | 7.8 | 15.7 (–19.6 to 66.6) | 0.458 |
| Large cone |
11.4 (10–24) |
44.4 (31.6) |
–5.2 |
–10.5 (–35.5 to 24.2) |
0.509 |
| Multiple chicken slaughtering, n = 27§ | |||||
| Open barrel without lid | 10.4 (10–14) | 130.1 (27.5) | Referent | – | – |
| Barrel covered with solid lid | 10 (10–10) | 36 (13.6) | –84.5 | –64.8 (–69.2 to –59.7) | <0.001 |
| Barrel covered with star-cut lid | 10.7 (10–20) | 34.3 (21.2) | –85.5 | –65.5 (–71.9 to –57.7) | <0.001 |
| Small cone | 10.2 (10–12) | 112 (52.3) | –8.3 | –6.3 (–21.6 to 11.9) | 0.470 |
| Large cone |
12.6 (10–36) |
131 (60.1) |
13.1 |
10 (–8.2 to 31.8) |
0.327 |
| Single chicken defeathering, n = 9 | |||||
| Open machine without lid | 10 (10–10) | 20 (6.5) | Referent | – | – |
| Machine half covered by hinged lid | 10 (10–10) | 17.5 (6.7) | –2.5 | –12.5 (–36.4 to 20.5) | 0.438 |
| Machine partially covered by lid with hole | 10 (10–10) | 13.3 (3.4) | –6.7 | –33.5 (–49.0 to –13.3) | 0.019 |
| Machine fully covered by lid with hole and pivot door | 10 (10–10) | 10.0 (0.0) | –10 | –50 (–59.4 to –38.5) | 0.002 |
| Machine fully covered by solid lid | 10 (10–10) | 10.0 (0.1) | –10 | –49.9 (–59.3 to –38.3) | 0.002 |
*PM2.5, particulate matter <2.5 μm in diameter. †PM2.5 mass concentrations were measured for 5 minutes before each experiment. ‡Calculated using 2-sample t-test. 1.25% was considered as level of significance instead of 5% according to Bonferroni correction. §Slaughtering events with 4 chickens at a time.
1Current affiliation: Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
Page created: March 04, 2026
Page updated: April 15, 2026
Page reviewed: April 15, 2026
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.