Aid agencies are battling to contain cholera in the Haitian capital Port-au-Prince, amid fears it will spread through camps housing 1.1m earthquake survivors.
More than 11,000 people have been infected since the outbreak began in October.
Roseann Dennery is working with the aid agency Samaritan's Purse near Cabaret, about one hour's drive north of Port-au-Prince.
"Today, our numbers sky-rocketed in Bercy, just north of Cabaret. The Samaritan's Purse cholera treatment centre is the only one servicing the area, and we are receiving people from nearby mountain villages, who appear to have been infected from their treks into the Cabaret market.
We started working here on Monday and we've been seeing 30 to 40 people a day. We're the only NGO working in Cabaret.
Today it got really hectic in the morning and we've seen something like 116 people through our station in the last 24 hours, 60 were new people today. We had 70 full beds and had to add 30 more this afternoon.
People are coming in on motorbikes and Tuktuks, near collapse. We've had to do many intravenous drips into the bone because the patients were too dry to put a line in elsewhere. It's a sign that the people we are seeing are very dehydrated.
It's starting to sink in with people that this could be a lot worse than we thought. When we are in nearby villages, there's an overall caution about travel, a feeling that the disease is moving and a heightened awareness of this.
We're trying to get ahead of the disease with education about the risks and hygiene preparation to reduce them. But our epidemiologist is worried that if it gets into some of the areas with the poorest hygiene, like Cite Soleil, then it could cause the outbreak to explode."