0 Wuhan scientists were studying viral samples of high-risk bat species living in Laos – the country where the closest relative to Covid-19 has been found, leaked documents show. In September, researchers discovered a viral strain called Banal-52 in Laos, which shares 96.8 per cent of its genome with Sars-CoV-2 – boosting claims that the pandemic was caused by a natural spillover event, rather than a laboratory leak.…