Denise Bucumi Nkurunziza, the wife of outgoing Burundi President Pierre Nkurunziza, is being treated at Aga Khan University Hospital after contracting Covid-19.
A source at the hospital said Mrs Nkurunziza is receiving treatment for an underlying condition as well.
She was airlifted to Nairobi on Thursday morning following a government-to-government agreement using Amref's acquired portable isolation chamber, which is an innovative medical unit and transportation system designed for optimal safety during patient loading and transport.
A source said the unit is a single patient isolator made of cleanable materials and is compatible with leading ambulance-stretcher systems as well as with most mechanical ventilator circuits.
"Due to our patient confidentiality policy, we cannot share any information with the public," the hospital's communication department stated.
Ministry of Health Chief Administrative Secretary Mercy Mwangangi said the Ministry of Foreign Affairs would confirm the matter as well as if other non-Kenyan residents would be allowed to seek treatment in the country.
"Kenya has a good medical structure and we continue to celebrate and promote that in terms of medical tourism. This is an issue that touches on foreign affairs and a comprehensive statement will be issued as to whether other people will be allowed to travel to Kenya for treatment," she said.
Burundi has put up a lacklustre fight against the coronavirus and the landlocked country of some 11 million has officially recorded 42 cases and one death from the coronavirus.
It has taken few precautions against the disease and testing is low, fuelling concerns that the true extent of the outbreak is not known.
The Burundi government ordered the country's top World Health Organization (WHO) representative and three other experts coordinating the coronavirus response to leave the country.
The expelled officials include WHO representative Dr Walter Kazadi Mulombo, the country's coronavirus coordinator Dr Jean Pierre Mulunda and Professor Daniel Tarzy.
Burundians went to the polls on May 20 to choose a new president, parliamentarians and local officials.
The country's election commission said on Monday the governing party candidate, retired General Evariste Ndayishimiye, had won the presidential election with 69 per cent of the vote.
It added that candidate Agathon Rwasa got 24 per cent of the vote and the election was peaceful.