Definition of Infected Influenza A (H1N1) Cases

Suspect Case

Defined as an individual with an acute febrile respiratory illness (fever >38°C) with onset of symptoms:

  • Within 7 days of travel to affected areas; or
  • Within 7 days of close contact with a confirmed or probable case of Influenza A (H1N1)

Probable Case

Defined as an individual with an acute febrile respiratory illness (fever >38°C) with an influenza test that is positive for Influenza A but is un-subtypeable by reagents used to detect seasonal influenza virus infection, OR;

An individual with a clinically compatible illness or who died of an unexplained acute respiratory illness who is considered to be epidemiologically linked to a probable or a confirmed case.

Confirmed Case

Defined as an individual with laboratory confirmed Influenza A (H1N1) virus infection by one or more of the following tests:

  • Real-time RT-PCR;
  • Viral culture;
  • Four-fold rise in Influenza A (H1N1) virus specific neutralising antibodies.