Following the sudden and unexpected emergence of influenza A(H1N1)pdm09 (2009 H1N1) virus, this observational study was initiated to describe participants seeking medical care in geographically diverse locations with 2009 H1N1 infection and their clinical course over a 14-day period following enrollment. In 2011, as surveillance indicated that 2009 H1N1 virus was co-circulating with other seasonal influenza A and B viruses worldwide, the protocol was expanded to include other influenza A subtypes and influenza B viruses. This version of the protocol further broadens the scope of this observational study. With the recognition that novel respiratory viruses other than novel influenza A viruses, e.g., Middle East Respiratory Syndrome Coronavirus (MERS-CoV), could become prevalent and of major public health importance, the objectives of this protocol have been expanded

The purpose of this observational study is to describe participants in geographically diverse locations with influenza virus infection and other viral respiratory diseases of public health importance and their clinical course over a 14-day period following enrollment.

Specific objectives related to influenza virus infection are to estimate the percentage of participants who go on to develop severe disease or complications that require hospitalization; to obtain information on risk factors for disease severity; and to establish a central repository of specimens for use in virus characterization, including subtyping, antigenic and genetic analyses, identification of signature mutations associated with antiviral drug resistance, mutational evolution, and additional reassortment.

Specific objectives related to novel non-influenza respiratory viruses of potential major public health importance are to characterize initial cases and their outcomes in order to develop more specific protocols that could inform the prevention and treatment of these new infections

Sample size is open-ended for this observational study. Based on experience to date, it is estimated that 75 sites will participate and will enroll approximately 1,700 patients with influenza each year, about one-half in the Northern Hemisphere and one-half in the Southern Hemisphere. Sites in diverse geographic locations on several continents will participate.

Study Plan:

• Participants who meet the eligibility criteria will be enrolled at participating clinical sites.
• At enrollment, consent is signed and information (demographics, medical history (including prior influenza and pneumococcal vaccination), medications (including antivirals) and treatments prescribed will be recorded. A blood sample for serum and plasma will be obtained at enrollment, as well as an upper respiratory tract specimen. The respiratory specimen will be sent for central reverse transcriptase polymerase chain reaction (RT-PCR) testing for influenza.
• Status will be re-assessed at approximately 14 days after enrollment and another blood sample for serum and plasma will be obtained. For participants with a confirmed novel respiratory virus of public health importance, attempts will be made to obtain a sample of the local specimen used to diagnose the infection.

In February 2012, the FLU 004 Genomics protocol v 1.0 was released to the field.

In August 2013 v 2.0 of the protocol was released as INSIGHT Genomics. The protocol was expanded beyond the FLU 002 and FLU 003 studies to include all qualifying INSIGHT studies (list posted on the INSIGHT website, www.insight-trials.org. The purpose of this substudy is to obtain a whole blood sample from which DNA will be extracted to study polymorphisms in immune response genes and other genetic variants that may be associated with an increased risk of disease progression among individuals with infectious diseases of public health importance who are enrolled in qualifying INSIGHT studies.

Participating FLU 002 Plus sites are given the option to also participate in INSIGHT Genomics, which requires a separate protocol registration. Participants, once consented to FLU 002 Plus, will be offered the option to also consent to INSIGHT Genomics, which includes a single whole blood sample collection. Participation in FLU 002 Plus will not be compromised if a participant opts not to participate in INSIGHT Genomics.

Inclusion Criteria:

• Be ≥ 18 years of age
• Have a signed informed consent by participant
• Have a fever (37.8 degrees C (100 degrees F) or higher on examination or patient-reported fever (37.8 degrees C (100 degrees F) or higher, or feverishness (felt febrile but did not take temperature) in the past 24 hours.
• Have a cough and/or sore throat
• Have suspected influenza or a suspected targeted non-influenza viral respiratory infection

Exclusion Criteria:

- Current imprisonment, or compulsory detention (involuntary incarceration) for treatment of a psychiatric or physical illness.

Persons who seek medical care and are suspected of having influenza or a targeted novel respiratory virus* of major public health concern will be enrolled at numerous participating clinical sites on several continents.

*The current list of other targeted novel respiratory viruses includes MERS-CoV and SARS-CoV.