Resume de l’article : Épée du 6e siècle, plus grand site d’empreintes de dinosaures et grippe aviaire : l’actu des sciences

Article summary and answer:

The article presents three brief science news stories. The first one is about the discovery of a 1,500-year-old sword in a Swedish lake, which was used to cut through bones and analyze the DNA of ancient meals. The second news is that a site in Bolivia has been identified as the largest dinosaur footprint site in the world, with over 5,000 prints. The third story is a warning from the WHO about the increasing risk of avian flu outbreaks and the need for better preparedness.

The answer to your question is:

The largest dinosaur footprint site in the world has been discovered in Bolivia, with over 5,000 prints.