Just as many countries around the world were beginning to loosen their border restrictions, reports of a newly detected coronavirus variant in South Africa sent many of those doors slamming shut again.

Co-founded by publisher Angela Wachuka and author Wanjiru Koinange, Book Bunk is working to renovate libraries across Nairobi.

Salim Abdool Karim, an epidemiologist and former co-chair of South Africa's Ministerial Advisory Committee on Covid-19, tells CNN's John Berman that a travel ban will have little, if any, impact on slowing the spread of the Omicron variant of Covid-19.