Nearly 50 people have contracted cholera while attending a health conference in Weston Hotel, Nairobi.
The infected delegates were among hundreds who had gathered for the four day forum organised by the Ministry of Health on Tuesday.
They have been isolated at Kenyatta National Hospital, but health officials say the number of people infected may rise.
It is unclear how they caught the disease, which has led to five deaths in the past month.
Nairobi county Health Minister Dr Benjamin Muia told the BBC "The situation is under control. We can assure the public that we are fully prepared for any eventuality. If there is an outbreak of cholera in the city, we have a solid plan of how to tackle it."
Cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholera.
Most of those infected will have no or mild symptoms but, in severe cases, the disease can kill within hours if left untreated.
In Yemen, a large cholera outbreak is fast approaching 300,000 cases, according to UN humanitarian chief Stephen O'Brien. He described it as a "man-made catastrophe" caused by both sides of the country's ongoing civil war.
Kenya's Ministry of Health said in
a press release
on 24 May that
there had been 146 cases across the country since the outbreak began.
Some of those infected had attended a wedding at an upmarket estate in Nairobi.
As a result, authorities put in place emergency measures to try and curb its spread.
An outbreak two years ago killed 65 people across Kenya.