Generally it will not be appropriate to conduct contact tracing of patients or to provide anti-viral prophylaxis. However if there has been a particular type of contact between a healthcare worker and a patient (for example intubation) or a patient is at high risk of severe or complicated infection, then further risk assessment is indicated with a view to offering prophylaxis. An alternative approach, if practical, is to monitor exposed persons and administer antiviral treatment when symptoms develop. When a vaccine becomes available the first priority should be to immunize healthcare staff.