Poultry supplies, the primary source of protein in the Gaza Strip, were being severely affected by measures implemented to contain the spread of the H5N1 avian flu virus. According to Ambrogio Manenti, regional head of office for the United Nations World Health Organization, the recent closures of the Karni border crossing with Israel have limited the import of alternative protein sources, further increasing concern over a nutrition gap in the Palestinian food supply. At a press conference in Jerusalem on Thursday, UN officials commended Israeli-Palestinian cooperation on the avian flu threat and called for increased aid in fighting the spread of bird flu in the Palestinian territories. Some 250,000 birds have been culled by UN officials and PA agencies so far. The figure represents 10 percent of the total estimated number of fowl in the Gaza Strip. More than 30,000 farmers lost their chickens to the culling and were left unable to provide for their estimated 200,000 family members. An additional 250,000 birds were slated for culling, according to UN officials, who said they believed the process would be carried out within a few days. The culling is conducted by UN and Palestinian health officials through the poisoning of the chickens' water supply. This is only done once the farmers give their permission, after which the corpses are gathered and buried between layers of plastic sheeting in deep ditches outside the farms. The farmers were promised compensation by the UN and the PA. However, according to Luigi Damiani, project manager for the UN's Food and Agricultural Organization, compensation involves more than just paying for the chickens. It must compensate for the downtime in which the farmers have nothing to sell and for restocking once the bird flu threat has passed. The process of culling, vaccinating and restocking, Damiani cautioned, would take many months. The lack of animal protein in the Palestinians' food supplies during this time was particularly problematic for children. Although Israel was being "proactive" in dealing with the bird flu threat both inside Israel and with regards to the PA, UN Special Coordinator for the Middle East PeaceProcess Alvero de Soto said that the "irregular opening of the Karni crossing" represented a significant problem. While this problem was long-standing, the UN envoy said, the bird flu situation has made it more pronounced. When asked if any measures were being taken to replace protein supplies in the Palestinian territories, Damiani said that there were discussions in the World Food Programme regarding the addition of fish to food supplies already being sent to the Palestinian territories. In addition, Damiani suggested, if Israel would allow fishing off the Gaza coast, it could add sardines to the Palestinian market. "Sardines are a cheap fish," he noted, "so the average person will be able to afford it." Israel provided several dozen doses of the anti-viral drug Tamiflu on loan to the PA, Manenti told reporters, adding that countries needed to purchase enough doses of Tamiflu to treat 25-30% of their population. But, he said, "even Israel can't afford that." The PA needed doses for at least 3% of its population just to deal with the direct threat of infection, at a cost of some $2 million. Meanwhile, Manenti said, the UN needed several hundred doses immediately for those officials and farmers who were exposed to the infected birds. A WHO mission to the Gaza Strip will release its findings later on Thursday regarding the spread of bird flu in Israel and the Palestinian Authority and will issue specific recommendations for responding to the threat. In mid-March, bird flu was confirmed in Israel in two agricultural communities outside the Gaza Strip. By March 23, the PA had confirmed bird flu cases in two commercial chicken farms in Gaza. No human cases have been reported in either Israel or the Palestinian territories.