Transmission from person to person has not been documented. Most human infections are silent. Pulmonary oedema and frank shock may feature. The haemorrhagic element is due to thromobocytopaenia, though substantial haemorrhage is uncommon. Laboratory confirmation is by serology and the outcome of the illness may be influenced favourably by intravenous Ribavirin.
Death is from non-cardiogenic pulmonary oedema and the adult respiratory distress syndrome.
In Europe, in 1993, documented hantavirus infection has been commonest in Germany and The Netherlands. In the UK, those most at risk are farm and sewage workers. The risk is not purely theoretical - GPs in Somerset, alerted to the syndrome, identified 5 cases in 1992. The risk to the public at large, and particularly campers and hikers, is extremely small. Since the withdrawal of this preparation last year, there has been no way for parents who initially decided against pertussis immunisation for their child to reverse that decision.