Employees of Safaricom based at one of the company's customer care shop have all tested positive of Covid-19.
All 13 employees based in Meru County on Wednesday were among the day's cases announced by the Ministry of Health's Chief Administrative Secretary Dr Rashid Aman.
This brings to 14 the number of Safaricom staff who have tested positive for the coronavirus after another employee was reported to have contracted the virus on Friday last week.
According to Meru Health Executive Misheck Mutuma, about 42 contacts of the patient who was isolated on Friday had been quarantined by Wednesday.
"The 13 positive tests are from the 42 contacts who are in quarantine. We have embarked on tracing more contacts from the new cases," Mr Mutuma said.
Following the confirmation of the Covid-19 case on Friday, Safaricom closed its Meru shop until further notice.
Meru Health Chief Officer James Kirimi said contact tracing had been escalated following the record number of coronavirus cases in the county.
"The 13 include seven males and six females. We are well prepared to manage all the patients at the Meru Teaching and Referral Hospital," Dr Kirimi said.
The latest cases come just days after Safaricom was forced to close four shops to allow cleaning, fumigation and sanitization.
In a statement last week, the company said the closure had been undertaken to safeguard the wellbeing of its staff and customers.
The affected shops are Nyali and Rex House both in Mombasa as well as Thika and Lavington Mall both within the Nairobi Metropolitan Area.
"We will be undertaking such measures regularly to our shops and customer facilities to safeguard the health and well-being of our staff and customers as this remains our topmost priority even as we continue to help the country in managing the Covid-19 Crisis," Safaricom CEO Peter Ndegwa said in a statement then.
On May 31, Safaricom was also forced to close its Thika Road Mall (TRM) in Nairobi after a staff member tested positive for coronavirus.
Ndegwa said the staff working at the shop had been isolated for treatment, while the shop had been shut temporarily for cleaning and sanitization.
"Safaricom PLC was notified that one of our staff members working at the Thika Road Mall shop has tested positive for Covid-19. The employee is currently in isolation and receiving appropriate medical attention," he said in a statement.
All other staff members who were working with the affected employee at Thika Road Mall were also informed and counselled.
"They are undergoing screening to ensure their safety and wellbeing," the CEO said.
On Wednesday, the country recorded 184 positive cases, the highest ever since its first case on March 13 bringing the case-load to 4,044.