The Covid-19 pandemic has been one of the weirdest things any of us has lived through. But there was another sickness that once stalked the nation and turned things very strange for a while. In the 1990s Britain was hit by an epidemic of a fatal neurological disease in cows that also killed 178 humans. Science was split between government assurances of safety and dissidents warning of disaster. Trust in officials took a battering. Facts became blurred. And the grisly truth about our global industrialised meat industry was revealed. 30 years on, scientists and activists are still...