They cite deteriorating economic conditions and the Covid-19 containment measures
East African countries are poised to get nearly 40 million Covid-19 vaccine doses though the AU initiative.
His re-election last Thursday will take Mr Museveni to 40 years in power by the next election in 2026.
The capital city has seen a second wave of Covid-19 after authorities relaxed some restrictions.
The five highly-affected countries are South Africa, Morocco, Tunisia, Egypt and Ethiopia.