The new data up to December 26 of 432 more recorded deaths compared with previous Haitian health ministry data marked a major jump in fatalities, although it was unclear exactly when they occurred.
The number of confirmed cholera deaths on December 19 alone was just over 100, the new data showed, far higher than previous peaks around 80 in mid-November.
More recently, the death tolls have returned to previous averages of around 50 new reported deaths each day.
The total number of infections soared towards 150,000 in Haiti and authorities in neighbouring Dominican Republic said Thursday there have been 139 cases there, none of them fatal.
Haiti's first cholera outbreak in more than a century has poured further misery on a poor and politically dysfunctional country trying to recover from a devastating January earthquake that killed some 250,000 people.
The epidemic, which began in October, spawned anti-UN riots last month as some turned their anger on peacekeepers from Nepal accused of bringing the disease into the country.
Experts say the outbreak was likely sparked by a human source from outside the region and the United Nations has promised a thorough investigation into the origin of the epidemic.
Angry mobs in the deeply superstitious nation have stoned or hacked to death at least 45 people – most of them voodoo priests – accusing them of spreading the waterborne bacterial infection.
Cholera, which causes potentially deadly cases of diarrhoea, often strikes in poor countries where there is a high danger of an epidemic due to inadequate sanitation and limited access to clean water.
The Pan-American Health Organization in early December estimated Haiti could see up to 400,000 cholera cases over the next 12 months, half of them within three months alone.
The epidemic comes against the backdrop of deep political uncertainty.
Flawed first round elections November 28 to find a successor to President Rene Preval are to be the subject of a recount monitored by international observers.