A passenger died on Thursday night in a Mombasa-bound bus from Busia.
Police in Makueni confirmed the death on Friday morning.
County commissioner Maalim Mohammed said the man was in a Simba Coach bus with 32 people on board.
The bus had stopped at Mukaa in observance of the 10pm curfew restrictions.
Most of the travellers alighted for refreshment. They found the man dead when they returned to the bus.
"Immediately we got the report, we assigned officers to the location to make sure there was no movement in and out of the bus. We notified public health officials and no one was allowed to leaveuntil dawn," the administrator told the Star.
The body was moved to Machakos Referral Hospital.
The man, who was accompanied by his sister, had a body temperature of 36.2 degrees Celsius before departure, Mohammed said.
The sister said the man had been sick.
"We have taken personal details of all the passengers in case of anything. At the moment, they will be allowed to go on the same bus with caution not to interact with other people," Mohammed said.
He said doctors counselled the passengers and assured that the man had pre-existing medical conditions that may have resulted in his death.
The bus was fumigated before continuing with the journey.
