A staff member introduces a potential COVID-19 vaccine developed by BioNTech and Fosun Group at the Medical Equipment and Healthcare Products exhibition area during the third China International Import Expo (CIIE) in Shanghai, east China, Nov. 5, 2020. (Xinhua/Zhang Yuwei)

Globally, there are 163 COVID-19 candidate vaccines in preclinical evaluation and 51 others in clinical evaluation, according to a publication of the WHO.

by Xinhua writer Liu Yanan

NEW YORK, Dec. 5  -- The world's top scientists on the development of COVID-19 vaccines on Friday expressed optimism about and confidence in having affordable vaccines with equitable access to all despite challenges regarding funding, purchasing, distribution as well as information.

"I'm very optimistic and also confident that if we continue to mobilize everyone who is a stakeholder in vaccine development and distribution, we will make that happen," said Oezlem Tuereci, chief medical officer at the German vaccine developer BioNTech.

Scientifically and technologically it is possible to make COVID-19 vaccines a global public good, said Soumya Swaminathan, the World Health Organization (WHO) chief scientist.

"We are confident that we're going to have several candidates that are safe and effective," taking into account all the work that is going on and the many more vaccine candidates under development, said Swaminathan, who was speaking at a panel discussion of one special session of the United Nations General Assembly in response to the COVID-19 pandemic.

"We're in a very exciting stage now where we're seeing efficacy results coming out on the first vaccine licensure," said Sarah Gilbert, professor of vaccinology at Oxford University.

"That's not an option. We have to achieve it and we can achieve it," said Ugur Sahin, chief executive officer with BioNTech.