<p>The lab leak theory goes mainstream. How safe are top-security laboratories?</p><p>After the World Health Organization’s attempts to find the origin of Covid effectively rule out a lab leak, there’s a backlash. A new US president helps bring the lab leak theory into the mainstream. What are the dangers involved in the work being done in virology laboratories? How effective are their safety measures? And do the benefits of their work outweigh the risks? John visit’s a top biosafety lab to find out.</p><p>Archive: CGTN; CBS; The White House; CNN; C-SPAN.</p><p>Presenter: John Sudworth
Series producer: Simon Maybin
Editor: Richard Vadon
Sound design and mix: James Beard
Commissioning editor: Dan Clarke
Science advice: Julian Siddle and Victoria Gill
Extra production: Eva Artesona and Kathy Long
Research support: Zisheng Xu and BBC Monitoring
Production coordinators: Siobhan Reed, Helena Warwick-Cross, Sophie Hill, and Debbie Richford
Theme and original music: Pete Cunningham, with trumpet by Joss Murray
Radio 4 Editor of Editorial Standards: Roger Mahony
Head of BBC News - Long Form Audio: Emma Rippon</p>
