Medical disinformation is a growing concern for doctors and scientists, but what happens when it comes from people in the highest authority who are shaping health policy? Recently US President Trump claimed a link between austism and the pain killer tylenol, or paracetamol as it is known here. The US Health Secretary, Robert F Kennedy Junior has also blamed vaccines for autism when there is no evidence to support his claims. Dr Ashani Weeraratna is a leading cancer researcher and was a guest speaker at this week's New Zealand Society for Oncology annual meeting. She spoke to Lisa Owen.