Official reports on Wednesday said 1800 people were killed in Haiti, while in the Dominican Republic it stood at 350 bodies had been recovered with 375 listed as missing.
The worst hit areas have been the Dominican town of Jimani and the southeastern region of Haiti near the border dividing the island of Hispaniola shared by the two countries.
In southeastern Haiti, 272 deaths were reported in and around the town of Mapou Belle-Anse and at least 100 in the Grand Gosier area. Another 165 died in the hard-hit town of Fonds Verrettes northeast of the capital, where the UN's World Food Programme (WFP) managed to bring in three tonnes of emergency food on Wednesday.
The WFP said it was targeting a total of 300 tonnes of food for Fonds Verrettes and other hard-hit regions.
The island is at the eye of a fierce tropical storm that has been lashing the Caribbean over the past 10 days.
Women, children killed
Jimani was devastated after the rain-swelled Soleil river burst its banks and swept hundreds of people, many of them women and children, from their homes, as thousands were evacuated.
Rescue workers are struggling to
find survivors in the mud
Jose Luis German, spokesman for the Dominican National Emergency Commission, said 300 were confirmed dead in Jimani, 120 were injured and 375 missing, with the toll rising steadily.
Fonds Verrettes, an agricultural town of 45,000 in Haiti built on a dry riverbed northeast of Port-au-Prince, reported 165 dead, along with 546 houses destroyed and more than 3000 heavily damaged.
Felix Dotel, a doctor with the local Jimani health department, said up to 1000 may have died in the town because the local authorities did not have an accurate register of the population.
The torrential rain showed no signs of abating on Wednesday as rescuers dug through the mud and local authorities buried many of the dead in mass graves. More than 100 unidentified bodies were buried in a grave in a forest outside Jimani on Tuesday.
Authorities said nearly 30,000 people had been evacuated from their homes in the Dominican Republic.
In Haiti, members of the multi-national force brought in to assure security after deposed president Jean Baptiste Aristide resigned and fled at the end of February were trying to get emergency supplies to the worst-hit areas.
United Nations and other aid workers were trying to reach hard-hit areas.
Multi-national force helicopters were ferrying food, water and emergency medical supplies.