Whether people should take third or fourth booster doses will depend on the epidemiological situation in the phase to come, he said in televised remarks on Monday.
Coronavirus and seasonal influenza vaccines are more or less similar in that vaccination against them grants immunity for a limited period of time, usually six to nine months, Tageddin said.
Several waves of COVID-19 are spreading in many countries, including China and North Korea, the adviser said, adding that he hopes Egypt will not face another wave.
Egypt has vaccinated its citizens with about 83 million shots against COVID-19, he said, adding that several million people have received booster shots.
Tageddin said the most commonly prioritised target populations for booster doses are older adults and immunocompromised individuals.