A vaccine volunteer gets an injection at the Chris Hani Baragwanath hospital in Soweto, Johannesburg Wednesday, June 24, 2020.

(AP Photo/Siphiwe Sibeko)

JOHANNESBURG (AP) — Africa’s first participation in a COVID-19 vaccine trial started Wednesday as nervous volunteers received injections, while officials said the continent of 1.3 billion people cannot be left behind.

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The pandemic was delayed in Africa “but is picking up speed very quickly,” the Africa Centers for Disease Control and Prevention chief John Nkengasong said Wednesday, with a steep increase in the number of cases and deaths.

Vaccine volunteers are seated, at the Chris Hani Baragwanath hospital in Soweto, Johannesburg Wednesday, June 24, 2020.

(AP Photo/Siphiwe Sibeko)

African leaders have been outspoken about the continent being elbowed out in the intense global competition for medical supplies in this pandemic, as well as what the World Health Organization’s Africa chief, Matshidiso Moeti, called the “distortion of the global market for key items.”