Officials in Pakistan raised concern over the spread of waterborne diseases among thousands of flood victims as waters from powerful monsoon rains began to recede in many parts of the country.

Some doctors said initially they were seeing mostly patients traumatized by the flooding, but are now treating people suffering from diarrhea, skin infections, and other waterborne ailments in the country’s flood-hit areas.

The development has forced the government to deploy additional medical teams, dispatch medicine, and provide clean drinking water to survivors, many of whom are living in tents and makeshift homes. The warning came a day after record-breaking floods prompted the United Nations to formally issue an appeal for $160 million in emergency funding to the impoverished Islamic nation, where about a million homes have been damaged or destroyed.

Dr. Azra Fazal Pechuho, health minister in the country’s worst-affected province of Sindh, said officials have set up 4,210 medical camps in the province’s flood-hit areas to treat victims now suffering from skin and waterborne diseases, which are common during floods.