Kariuki takes over from Dr Alfred Mutua who quit three months ago to contest the seat of governor for Machakos County.
Kariuki, 56, joined the VP’s office as an advisor on April 14, 2010.
He confirmed to Capital FM News that he had received his letter of appointment signed by President Mwai Kibaki from the Head of the Public Service.
The appointment takes effect immediately.
Kariuki who served as a media manager for president Kibaki during the 2002 election is a long-standing PR practitioner.
Between 1997 and 1999, he worked for Kenya Breweries Limited as the PR Manager. Prior to that he was the Deputy Public Relations Manager at the brewer between 1992 and 1997. Between 1987 and 1992 he was an Assistant Public Relation Manager at KBL.
He also worked as a clerk with Kenya Commercial Bank in the late 70s.
He plays golf, likes writing, reading and travelling.