Pakistani health officials are reporting an outbreak of waterborne diseases in the flood-affected areas

ISLAMABAD — Pakistani health officials on Thursday reported an outbreak of waterborne diseases in areas hit by recent record-breaking flooding, as authorities stepped up efforts to ensure the provision of clean drinking water to hundreds of thousands of people who lost their homes in the disaster.

The U.N. children’s agency said more than 3 million children were in need of humanitarian assistance and stood at heightened risk of diseases, drowning and malnutrition due to the most severe flooding in Pakistan’s recent history.

Pakistani authorities and aid agencies also were working to secure medical facilities to thousands of pregnant women, who are among 33 million people affected by floods.

Diarrhea, skin diseases and eye infections are spreading at relief camps set up by the government across the country. Over 90,000 diarrhea cases were reported from one of the worst-hit provinces, Sindh, in the past 24 hours, according to a report released by the health officials. But the illnesses were also reported from other flood-hit areas.

The grim updates came a day after Pakistan and the World Health Organization raised concern over the spread of waterborne diseases among flood victims. Pakistan blames climate change for unusually early and heavy monsoon rains, which since June have caused flash floods that have killed 1,191 people and affected 33 million people. About a million homes have also been damaged or destroyed

Flood waters continued to recede in the most of the country, but many districts in southern Sindh province remained underwater, forcing displaced people to stay at donated camps.

Among those flood victims staying at a relief camp in the district of Shikar Pur in Sindh was Mundam Ali, 21, who is seven months pregnant. She said she has a backache and cough. Ali said she had no other choice except to live in the relief camp, as her village was still submerged.

Ramesh Kumar, a medical doctor in Shikar Pur, said he treated scores of flood victims and most of them had waterborne diseases.

Nearly half a million flood displaced are living in relief camps. In Sindh province, thousands of medical camps have been set up in flood-stricken areas to treat victims, said Dr. Azra Fazal Pechuho, the provincial health minister. Mobile medical units have also been deployed. The World Health Organization says it is increasing surveillance for acute diarrhea, cholera and other communicable diseases and providing medical supplies to health facilities.

Doctors say initially they were initially seeing mostly patients traumatized by the flooding, but are now treating thousands of people suffering from diarrhea, skin infections and other waterborne ailments. Many pregnant women living in flood-affected areas were also exposed to risks.

Farah Naureen, the director for Pakistan at international aid agency Mercy Corps, said waterborne diseases were increasing at a faster pace among displaced people in flood-hit areas. In a statement, she said other than infectious diseases, the health of women was of particular importance.

“Around 73,000 will be giving birth within the next month, and they need skilled birth attendants, privacy, and birth facilities, or the survival of the mother and the newborn will be at risk,” she said.

According to Minister for Poverty Alleviation, Shazia Marri, the government was aware of the problems faced by pregnant women and children and was acting swiftly to help.

According to the U.N. Population Fund, 6.4 million flood victims in Pakistan need humanitarian assistance. It said about 650,000 pregnant women in flood-affected areas, including 73,000 expected to deliver in the next month, need maternal health services.

Children were at special risk, UNICEF said in a statement.

“When disasters hit, children are always among the most vulnerable,” said Abdullah Fadil, UNICEF representative in Pakistan. The floods damaged 17,566 schools, the agency said.

Meanwhile, rescuers, backed by the military, continued operations to evacuate marooned people to safer places. Rescuers are mostly using boats, but helicopters are also flying to evacuate stranded people from those areas where bridges and roads were destroyed, making it difficult to evacuate people and deliver food to them.

Days ago, Pakistan and the United Nations issued an appeal for $160 million in emergency funding to Pakistan. Prime Minister Shahbaz Sharif on Thursday took to Twitter, thanking the United Arab Emirates for delivering the first tranche of relief goods worth $50 million. He also thanked the United States for announcing $30 million in aid.

So far, several countries, including Turkey, China, Qatar, and Saudi Arabia, have sent planeloads of aid to flood victims in Pakistan. According to initial government estimates, the devastation caused $10 billion in damages.

Associated Press writer Muhammad Farooq contributed to this story from Shikar Pur, Pakistan