Time and money are running out for relief operations in south Asia, where floods have affected 30 million people according to the World Health Organisation, and up to 50 million according to some officials*.
"Even if the rains stop, the danger remains, as flood water increases the risk of malaria and encephalitis," said Harjeet Singh of ActionAid India. "We are still in the middle of the monsoon season but the flood response is already running short of time and money."
ActionAid staff fighting the floods in Bangladesh say the most urgent problem is a severe shortage of drinking water, and the biggest fear is that disease will spread through the contaminated floodwaters.
Though the floods are now receding in the north of the country, the capital Dhaka is bracing itself for an inundation in the next few days as the waters flow downstream.
Relief workers are finding it difficult to reach flooded and marooned villages even by boat, because fuel is in short supply.
Meanwhile the floods in the north Indian state of Bihar are described by the United Nations as the worst in living memory.
"Bihar's poorest people, especially women and children, are living through the worst nightmare," said ActionAid’s Emergencies Advisor for Asia, P.V. Unnikrishnan.
Flood victims say that too often the food packets dropped by government helicopters only reach villages in the media spotlight. Many villagers have not had food parcels for days.
In the four worst hit districts of Sitamarhi, Samastipur, Muzaffarpur and East Champaran, ActionAid and its local partner organisations are distributing foods including rice and jaggery (sugar), shelter materials, halogen tablets and bleaching powder for purifying water, and oral rehydration salts for the treatment of diarrhoea.
In the northern state of Uttar Pradesh ActionAid is working in four of the worst hit districts - Maharajganj, Gorakpur, Siddarthnagar and Gondabaghi - providing transport for doctors to visit communities, and working with the government to organise medical camps.
In Assam in India's north-east, rivers have breached embankments in more than 50 places, inundating areas that are usually protected from the monsoon floods.
"The situation will worsen if the rains hit back, which is expected in the middle of the week" said Mrinal Gohain, Assam regional manager of ActionAid.
Reports are coming in of extensive flooding in Gadchiroli district in the western state of Maharashtra. Only a short time ago, farmers here were committing suicide rather than face ruin by drought.
"I was there last week and agricultural communities were fearing drought. Now there is flooding. Crops have been destroyed but this time by too much rather than too little water," said Kamini Ranjit Kapadia, ActionAid's regional manager in Maharashtra.
Field workers report that the water level is still rising. ActionAid's partner organisation Shughda has opened shelters in schools and is working with local people to move the most vulnerable individuals to safe areas.
In Pakistan, where 2.5 million people were affected by cyclone Yemyin in June and thousands are still homeless, the meteorological office has again predicted heavy rains in the south of the country.
ActionAid has delivered food, medicine and shelter to villagers in Nepal where floods and landslides have affected 200,000 people along the border with India, after torrential rains throughout the country.
Tomorrow (Wednesday 8 August) ActionAid will launch an appeal for donations at www.actionaid.org.uk