The Botswana health ministry says it has detected a new lineage of the Covid-19 Omicron variant.
The infected are currently being monitored to establish more information on the potential impact of the disease and its severity.
The new sub-variant, designated as Omicron BA.4 and BA.5 has already been detected in three other countries and on four people in Botswana.
The four people were fully vaccinated and had been experiencing mild symptoms.
So far, no conclusions have been made to establish whether this sub-variant is more transmittable than the known Omicron variant.
This happens as the World Health Organization announces it is tracking a few dozen cases of the two new sub-variants of the highly transmissible Omicron strain to assess whether they are more infectious or dangerous.