Volume 14, Number 10—October 2008
Research
Risk Factors for Nipah Virus Encephalitis in Bangladesh1
Joel M. Montgomery2
, Mohamed J. Hossain, E. Gurley, D.S. Carroll, A. Croisier, E. Bertherat, N. Asgari, P. Formenty, N. Keeler, J. Comer, M.R. Bell, K. Akram, A.R. Molla, K. Zaman, Mohamed R. Islam, K. Wagoner, J.N. Mills, P.E. Rollin, T.G. Ksiazek, and R.F. Breiman
, Mohamed J. Hossain, E. Gurley, D.S. Carroll, A. Croisier, E. Bertherat, N. Asgari, P. Formenty, N. Keeler, J. Comer, M.R. Bell, K. Akram, A.R. Molla, K. Zaman, Mohamed R. Islam, K. Wagoner, J.N. Mills, P.E. Rollin, T.G. Ksiazek, and R.F. BreimanTable 2
Exposures and activities associated with Nipah virus infection, Bangladesh, December 2003–January 2004*
| Exposure or activity | No. (%) study participants with reported exposure or activity† |
|||
|---|---|---|---|---|
| Case-patients, n = 12 | Controls, n = 36 | OR (95% CI) | p value‡ | |
| Animal exposure | ||||
| Touched any ill animal§ | 9 (75) | 31 (85) | 1.8 (0.29–8.52) | 0.613 |
| Touched or observed a dead animal§ | 6/10 (60) | 12 (34) | 2.4 (0.4–616.5) | 0.392 |
| Killed any animal§ | 3 (25) | 6 (16) | 1.8 (0.2–79.51) | 0.670 |
| Other animal exposures | ||||
| Contact with animal stool | 2/9 (22) | 12 (35) | 0.5 (0.05–3.04) | 0.679 |
| Visited a poultry farm | 3 (25) | 13 (37) | 0.6 (0.08–3.29) | 0.740 |
| Observed fruit bats around household at night
(1 mo before outbreak) |
4/11 (36) |
7 (19) |
4.1 (0.27–261.9) |
0.491 |
| Outdoor activity | ||||
| Climbed trees | 10 (83) | 19 (51) | 8.2 (1.25–∞) | 0.025 |
| Picked fruit from trees | 8 (67) | 18 (49) | 3.2 (0.54–36.0) | 0.262 |
| Picked fruit from the ground | 7/11 (64) | 27 (74) | 0.79 (0.13–6.09) | 1.000 |
| Fished | 6 (50) | 10 (28) | 4.5 (0.69–49.7) | 0.139 |
| Hunted | 2/10 (20) | 10 (28) | 7.3 (0.38–432.6) | 0.240 |
| Played hide and seek | 8/11 (73) | 21 (58) | 4.3 (0.38–∞) | 0.256 |
| Played cricket | 4 (33) | 18 (51) | 0.5 (0.09–2.76) | 0.552 |
| Played soccer |
5 (42) |
9 (24) |
2.4 (0.44–16.9) |
0.403 |
| Exposure to human illness | ||||
| Had contact with a suspect or probable Nipah virus encephalitis case-patient | 8 (67) | 3 (9) | 21.4 (2.78–966.1) | <0.001 |
| Visiting a hospital |
12 (100) |
7 (19) |
32.4 (5.18–∞) |
<0.0001 |
| Consumption of fruit | ||||
| Bananas¶ | 11 (92) | 24 (67) | 4.9 (0.61–226.7) | 0.199 |
| Buroys | 7 (58) | 28 (77) | 0.4 (0.078–2.37) | 0.433 |
| Papaya | 3 (25) | 14 (40) | 0.49 (0.08–2.24) | 0.497 |
| Guava | 2 (17) | 12 (33) | 0.5 (0.05–2.70) | 0.608 |
| Sofeda | 1 (8) | 2 (5) | 2.0 (0.03–38.4) | 0.976 |
| Kamranga |
1 (8) |
3 (9) |
1.0 (0.006–165.9) |
1.000 |
| Other environmental exposures | ||||
| Drinking raw DPS | 10/11 (91) | 26 (72) | 4.1 (0.47–197.0) | 0.328 |
| Harvesting DPS | 3 (25) | 3 (8) | 3.4 (0.37–43.6) | 0.365 |
| Drinking DPS from collection vessel | 5/10 (50) | 12 (32) | 1.7 (0.36–8.34) | 0.612 |
| Someone in household collects DPS | 4 (33) | 5 (15) | 2.3 (0.38–13.3) | 0.454 |
*OR, odds ratio; CI, confidence interval; DPS, date palm sap.
†Data are no. of study participants responding affirmatively/total no. responding (%) unless otherwise noted.
‡Exact method using univariate conditional logistic regression.
§Cows, horses, sheep, goats, pigs, ducks, chickens, dogs, cats, or fruit bats.
¶Fruit was obtained from a market or another person, if not picked directly from the tree or ground.
