Question category: Respiratory
A 52 year old gentleman has just returned from a cruise. He has developed had been unwell with fever, headache, myalgia and diarrhoea and vomiting with a dry cough. His cough is now more severe, with occasional haemoptysis and dyspnoea. Bloods reveal elevated WCC and CRP, hyponatraemia and deranged LFTs. What is the most likely causative agent?