Five days of vaccination against cholera are underway in Bauchi to stop the spread of cholera.

The target is to vaccinate some 600,000 people in high risk areas with the first dose before the start of Ramadan.

Nearly 270,000 residents received a first dose of the oral cholera vaccine in the first two days of the vaccination campaign, which started on May 9, said the group Medecins Sans Frontieres (MSF) or Doctors Without Borders, in a response to Bauchi’s appeal for assistance.

The epidemic has mainly affected urban local government areas of Bauchi.

The first case was recorded at the end of February, and by May 9, 4,536 cases had been reported across nine local government areas of Bauchi.

MSF says the rate of the epidemic is continuing to increase.

“We are still potentially in the early phases of the outbreak, given this region is regularly affected by serious and prolonged cholera epidemics,” said Miriam Harry, MSF project coordinator, in a statement.

More than 10,000 were infected in 2010 in Bauchi state. In 2014, Bauchi saw the most serious epidemic on record, with nearly 17,000 people infected.

Experts worry imminent rainy season could affected situation of water and sanitation, increasing potential for cholera to be spread.

“We feared this could develop into a massive cholera outbreak which would have a huge impact on the population, and that the response would be very difficult, said Dr Natalie Roberts, MSF emergency manager.

“It is therefore crucial to use all available means of control, which includes vaccinating as soon as possible. We know from our experience in cholera epidemics that providing people in high risk areas with one dose of the vaccine in addition to other control measures can quickly reduce or even stop the spread of the disease.”

MSF says Bauchi asked it to help define vaccination strategy, train and supervise vaccinatin teams, manage data and provide logistical support during the campaign—that would increase transporting vaccines.

MSF has been managing a 100-bed cholera treatment centre since the outbreak started, and setting up oral rehydration points.

A total 4,207 patients have been treated in in MSF’s structures between March 19 and May 6. The group also supplies chlorinated water to an average 160 households a day