Authorities confirmed the deaths were caused by the floods, taking the disasters' toll to 10.
A week of flooding has seen thousands of people evacuated, but 80,000 remain trapped.
Camped on rooftops
In the worst-hit state of Tobasco, where 80 per cent of the territory is submerged, many remained camped out on the rooftops or upper floors of their furnished homes to guard their possessions from looters.
However, some have been forced to give up their attempts at saving their goods.
"I would prefer to be in my house instead of a shelter, but we ran out of everything", said Patricio Bernal, 53.
She was evacuated by boat along with his wife from their home in the state capital, Villahermosa.
The homes of up to 500,000 people have been damaged or destroyed in the floods.
Rescuers are now said to be undertaking "selective evacuations", primarily of sick people, and delivering suppies to isolated communities surrounded by water.
Visiting Tabasco, Felipe Calderon, the Mexican president, said: "We are seeing one of the worst natural catastrophes in the history of the country."
"Not only because of the size of the area affected, but because of the number of people affected."
The government has said about half a million people have been affected by severed utilities and transportation links since rivers first burst their banks on October 28.
Four bridges and 290km of roads have been washed out in the neighbouring state of Chiapas.