More than 500 cases of cholera have been reported over the past seven weeks in Douala, the largest city in Cameroon, and at least 13 people have died of the disease, according to government statistics.
However, health workers told IRIN that the real cholera infection rate in the heavily polluted port city of 2.5 million people could be much higher than official figures suggest.
They said many cholera victims were not registering with state hospitals, but were seeking treatment from private doctors and traditional healers instead. These people were not being captured by official statistics, they added.
"There is really no drainage or sewage disposal system in Douala. Many people are using latrines which are barely two metres away from their toilets. So we virtually have the same water in both our wells and toilets," Jules Kamajou, an urban planner in Douala, told IRIN.
"Worse still, the sandy soils cannot filter the water well. With this kind of condition we should always be ready for a catastrophe," he added.
Kamajou said 98 percent of the well water that is used by city residents is polluted and unfit for human consumption.
There are about 8,000 wells in Douala, according to the head of mission of Medecins Sans Frontiers (MSF) in Cameroon, Max Antoine Grolleron.
"Many of these wells are not protected and are located near latrines which definitely drain into them. This is a very likely source of contaminated wells,” Grolleron said.
There are fears that the situation could get out of hand with the coming of the rainy season if urgent measures are not taken to contain the spread of the epidemic, he warned.
Already, 4,850 wells have been treated with chlorine. But this is can only be an interim solution, one health officer said. He told IRIN that the threat of cholera would continue so long as latrines and wells continue to compete for space in the densely populated city.
Cholera is an acute intestinal infection that causes a copious, painless, watery diarrhoea, vomiting and headaches. It leads to severe dehydration and death unless treated quickly.
The disease spreads rapidly in densely populated areas when water becomes contaminated with faeces. However, simple solutions such as boiling water can render it safe for drinking.
The current outbreak in Douala was first reported seven weeks ago in the densely populated neighbourhood of Bepanda.
Within days, eight deaths were reported at the the city's Laquitinie General Hospital.
Since then, many serious cases have been isolated for intensive care.
Cholera cases are being handled with the utmost urgency by the city’s hospitals, which have started counselling services for patients.
"We have the duty to treat our patients, monitor the evolution of the disease and educate them on how to avoid further contamination upon leaving hospital," said Estelle Minyam, a member of staff at the Laquitinie Hospital.
The government has urged people to wash their hands before eating and avoid drinking any water from doubtful sources. It has also advised Douala residents to boil all drinking water.
At the end of a cabinet meeting on Thursday, Prime Minister Peter Mafany Musonge announced a government directive prohibiting water sellers in Douala from operating near school premises. He also announced a plan to construct safe water tanks and stand pipes in the city to deliver safe drinking water to people without a mains supply.
Health Minister, Olanguena Owono, said recently the cholera outbreak was under control.
However, new cases of cholera are still being recorded in Douala, according to Dr Jeremie Solle, a public health official in Littoral Province, where the city is situated.
On 15 February, 35 new cases were treated in just one of the hospital of the city’s hospitals, he noted.
The World Health Organisation, the UN Children's Fund (UNICEF) and MSF are all helping to tackle the outbreak.