Why has no Gamma variant (P.1) been reported in Africa despite being found in 72 nations in the Americas, Asia, Europe and Australia? 

Every week the World Health Organization posts an epidemiological update that includes global maps (below) and nation-by-nation listing in Annex 1 (below) for each of their four variants of concern: Alpha, Beta, Gamma, and Delta.  Multiple nations in Africa have reported Alpha, Beta, and Delta variants. In contrast, no African nations are shown in this WHO weekly update as having reported the Gamma variant. 

This observation is based on both these WHO global maps from this week (July 6) when 74 nations across both Americas, Asia, Australia and Europe reported Gamma, and on Annex 1 listing in alphabetical order approximately 188 nations and presence or absence of the Alpha, Beta, Gamma, and Delta variants of concern. 

Looking back at several weekly WHO updates from as early as April 11 (when 40 nations had already verified and reported Gamma, through May 25 (when 59 nations reported Gamma) and June 29 (when 72 nations reported Gamma), the global maps do not show any African nations with Gamma, nor do any of the nation-by-nation line listings. 

While sequencing to identify variants is (likely) insufficient in at least some nations in Africa as well as the Americas, Asia, and Europe, some of the earliest and best sequencing took place in some laboratories in Africa.

In addition, the Alpha, Beta, and Delta variants appear in multiple African nations on these WHO maps (see right-hand side of WHO figure below for Delta and left-hand side for Gamma) and nation-by-nation line listings.  

There is no reason to doubt the accuracy of this data reported by WHO. No immunologic, genetic, or virologic speculation as to the cause seems immediately evident.