Haiti's cholera outbreak has spread to the country's largest jail, the national prison in Port-au-Prince.
The head of Haiti's prison service told the BBC that 30 inmates have been infected and 13 have died in recent days.
There are fears that the death toll could rise substantially in the overcrowded facility, which houses around 2,000 prisoners.
Almost 1,200 people have died in the outbreak, which began last month.
On Friday another 76 deaths were reported, bringing the total to 1,186, the health ministry said.
The International Committee of the Red Cross says its teams are working around the clock to make the national prison safe.
Jean Roland Celestin, the head of the prison system in Haiti, described the situation at the jail as serious.
Aid groups say the international response to the crisis in Haiti has been completely inadequate.
Imogen Wall, a spokeswoman for the UN humanitarian agency OCHA, told Reuters that the UN had only received $5m of the $164m it had appealed for a week ago to fight the epidemic.
Medecins sans Frontieres is urging all groups and agencies in the country to increase the scale and speed of their efforts.
"More actors are needed to treat the sick and implement preventative actions, especially as cases increase dramatically across the country," said Stefano Zannini, MSF's head of mission in Haiti.
"There is no time left for meetings and debate - the time for action is now," he said.
UN agencies have also had their work hindered in recent days by protests and riots by people angry about the epidemic.
Some Haitians blame United Nations peacekeepers from Nepal for bringing cholera to the country - a claim denied by the UN.
On Thursday police fired tear gas as demonstrators set up barricades and threw rocks at United Nations vehicles. Clashes on Monday in the north left two people dead.
UN humanitarian agencies renewed an appeal on Friday to stop the demonstrations, saying that lives are being lost because they can not reach people who need care.
UN officials argue that the violence is being encouraged by forces that want to disrupt a presidential election due on 28 November.
Cholera is present in all 10 of Haiti's regions.
The Cap-Haitien area has the highest fatality rate in the country but very little medical aid has been able to get through for days because of violent protests.
Most of the deaths recorded in the capital Port-au-Prince have been in the slum district of Cite Soleil.
Tainted food warning
The first cases of cholera - a water-borne disease - were reported near the Artibonite River north of Port-au-Prince. However, future outbreaks could result from tainted food, the Atlanta-based Centers for Disease Control (CDC) warned on Thursday.
Just 17% of Haitians had access to adequate sanitation before a devastating earthquake in January killed about 230,000 people, the CDC said, adding that the situation had considerably worsened since then.
It is unclear how cholera reached Haiti. There are claims that it originated from septic tanks at a base for UN peacekeepers from Nepal, but the UN says there is no evidence for this.
Cholera causes diarrhoea and vomiting, leading to severe dehydration. It can kill quickly, but is treated easily through rehydration and antibiotics.
More than 19,000 cases have been reported across Haiti.
The CDC and other agencies are trying to distribute oral rehydration solutions to combat the spread of the disease.