People line up for the COVID-19 vaccination at a vaccination center during the fourth mass COVID-19 vaccination day in Tunis, Tunisia, on Sept. 4, 2021. (Photo by Adel Ezzine/Xinhua)
A woman receives the COVID-19 vaccine at a vaccination center during the fourth mass COVID-19 vaccination day in Tunis, Tunisia, on Sept. 4, 2021. (Photo by Adel Ezzine/Xinhua)
Medical workers prepare the COVID-19 vaccine at a vaccination center during the fourth mass COVID-19 vaccination day in Tunis, Tunisia, on Sept. 4, 2021. (Photo by Adel Ezzine/Xinhua)
A man receives the COVID-19 vaccine at a vaccination center during the fourth mass COVID-19 vaccination day in Tunis, Tunisia, on Sept. 4, 2021. (Photo by Adel Ezzine/Xinhua)
People register for the COVID-19 vaccination at a vaccination center during the fourth mass COVID-19 vaccination day in Tunis, Tunisia, on Sept. 4, 2021. (Photo by Adel Ezzine/Xinhua)
A man receives the COVID-19 vaccine at a vaccination center during the fourth mass COVID-19 vaccination day in Tunis, Tunisia, on Sept. 4, 2021. (Photo by Adel Ezzine/Xinhua)
