The U.N. Office for the Coordination of Humanitarian Affairs said in a bulletin Saturday that an average of 180 new cases of cholera a day were reported between August 24 and 29, during the period the storm struck. There was an average of 78 new cases a day reported in the full week before the storm.
The increase followed a decline in the average number of daily cholera infections, from 241 in late July to 115 in August, according to the Haitian health ministry.
Cholera is a waterborne disease that spreads through the contamination of water and feces and causes rapid dehydration. It's easily treatable but thousands have died in Haiti because the country lacks infrastructure and people were unable to obtain treatment in time.
Cholera has infected more than 588,000 people and killed 7,500 others, health officials say, since it was likely introduced to Haiti in October 2010 by a unit of U.N. peacekeepers from Nepal, where the disease is endemic.
Tropical Storm Isaac killed at least 24 people in Haiti when floodwaters swept them away or falling trees or walls crushed them. Three others went missing.
There was also considerable damage to livestock and cattle.
The storm killed more than 2,000 head of cattle and damaged more than 80 percent of the crops in 10 departments, the U.N.