Hijjah 18, 1431/Nov 24, 2010, SPA -- The United Nations warned Wednesday that unless the international community adopts a stronger response against cholera in Haiti, the epidemic could affect up to 400,000 people. The UN doubled its projection from the current estimate of 200,000 Haitians getting sick from cholera, which is mainly transmitted through contaminated water. "This epidemic has not yet peaked," dpa quoted Valerie Amos, the chief coordinator for UN humanitarian affairs and emergency relief, who arrived in Port-au-Prince late Tuesday as saying. "The humanitarian work already being done in Haiti ... has already saved tens of thousands of lives. But it is not enough to curb the loss of life, or equip Haitians to tackle this crisis themselves," she said. The Pan-American Health Organization and World Health Organization said 400,000 Haitians could be affected, taking into consideration how rapidly the disease was spreading. But they said the projection is a worst-case scenario, which can be avoided if prevention and treatment measures can reach people in poor areas in capital Port-au-Prince and outlying towns. "The projection is a wake-up call," Amos said, calling for prevention measures to be taken across Haiti, while medical centres were being built and health workers hired to support the work already underway. The UN last week appealed for 164 million dollars to provide additional health centres, scale up information to help people deal with the epidemic and purchase supplies, medical equipment, rehydration salts, water purification tablets and train Haitian health workers. The World Health Organization (WHO) estimates an annual global burden of 3-5 million cholera cases and 100,000-120,000 deaths. While the disease can kill within hours if left untreated, no one needs to die from cholera. A simple sugar-and-salt solution can revive even the severely dehydrated.