The waterborne disease has killed at least eight people and is suspected of infecting more than 2,000, according to an international epidemiologist, Fred Hartman, who works on a US-supported health project. But the government said the death toll was lower and there was no reason to panic.

Nevertheless, hospitals were pitching dozens of tents in their yards to isolate patients should the number of cases spike.

Heavy Seasonal Rains

Abdullah Fahim, an adviser to the health minister, said all major water sources, including reservoirs, had been chlorinated, as well as 700 wells, the main source of water for many people. He said it wasn't clear how many wells were in the city, though it was believed to number in the thousands.

He said the outbreak of cholera and other waterborne diseases was caused by heavy seasonal rains raising the level of the groundwater that then mixes with sewage leaking from poorly maintained septic tanks.

"Kabul has no sewage system and septic tanks are close to wells and other water sources," Fahim said. "Water is easily contaminated."

Hartman, technical director for a US Agency for International Development-backed program, the Rural Expansion of Afghanistan's Community-based Health Care, said cholera had been detected in many wells around the city.

Major Killer in Developing Countries

Fahim said some 3,700 people have been diagnosed with acute diarrhea, but that only 30 had been confirmed to have cholera. He said two children and an adult who died with diarrhea were suspected of having cholera.

Hartman, who works closely with the Health Ministry, declined to comment on the government's lower death toll. He said individuals who show symptoms of the disease receive immediate treatment but are rarely tested to confirm they have the illness.

Cholera is a major killer in developing countries, where it is spread mainly through contaminated food or water. The bacterium attacks the intestine and causes severe diarrhea and dehydration. While potentially fatal, cholera can be easily treated if patients are rehydrated quickly.