USAID has released Sh4.4 billion to fund HIV and tuberculosis projects in Nairobi and the Coast region for the next five years.
The money will be channelled through the Aids, Population and Health Integrated Assistance Project whose earlier five-year funding ended last year.
Under the renewed funding, Aphia will also support family planning, malaria and maternal and child health programmes.
Usaid's head of HIV and Aids programmes Karen Klimowski said the new five-year phase, called Aphia-plus, will concentrate on interventions only.
"Over the next five years, this programme will engage every sector of the Kenyan society in every province to further improve the quality and accessibility of Kenya's health care services," she said.
Usaid has been funding Aphia II projects in five regions covering the entire country. Karen said funding for all other areas was renewed last month for the next five years.
"Aphia II was a very successful programme that made healthcare better throughout Kenya. To improve on these successes, we have modelled the Aphia-plus programme to respond to the specific needs of each region," she said.
Head of Aphia-plus in Nairobi and Coast Peter Eerens said the next five years will build on past successes.
"We are now consolidating gains made in the last five years," he said.
The programme works within the existing public healthcare system, Dr Eerens said.
Aphia-plus refers to People centred, Local leadership, Universal access and Sustainability (plus).
The launch yesterday was presided over by Nairobi PC Cyrus Waweru who said funded projects would help Kenya achieve health-related millennium development goals.
"Health status is worse among people living in slums because there are no government facilities there," he said.
Provincial director of medical services Pacifica Onyancha said that although Nairobi province is small it had the country's highest medical burden.
"Population characteristics of Nairobi are unique and people move around a lot," she said.
The population is 3.2 million at night but rises to up to six million during the day, said Onyancha.
Aphia-plus will give greater concern to most at risk populations to HIV.