LBMs in West Java province had a higher risk for contamination than did other provinces. This risk probably is due to greater AIV (H5N1) disease activity in the province. Surveillance activities during 2006-2008 showed that West Java had a 4.7% outbreak detection rate compared with rates in Banten (4%) and Jakarta (0.2%) (18) . Furthermore, in West Java province chicken density is high: 14,000 birds/km 2 compared with densities in the neighboring provinces Banten and Jakarta (3,900 birds/km 2 and 400 birds/km 2 , respectively) (19) . Poultry density data are commonly used as a proxy for disease activity where areas of high poultry density have the highest risk for an outbreak (20, 21) .