Interim Guidance for Clinicians on Human Infections with Variant Influenza Viruses | CDC

Interim Guidance for Clinicians on Human Infections with Variant Influenza Viruses | CDC

Guidance for Human Infections with Swine Flu Viruses

Swine flu is a respiratory disease of pigs caused by type A influenza viruses that regularly cause outbreaks of flu in pigs. While rare, human infections with swine flu viruses do occur and can be serious. Medscape’s CDC expert commentary gives clinicians recommendations on how to evaluate, test for, treat, and report human cases of swine influenza.

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Interim Guidance for Clinicians on Human Infections with Variant Influenza Viruses

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On This Page

• Background
• Clinical Presentation and Risk Groups
• Clinical Diagnosis
• Laboratory Diagnosis and Test Interpretation – Hospital and Clinical Laboratories
• Clinician Reporting
• Clinical Management
• Vaccination
• Prevention

Guidance for Clinicians: Variant Virus Infections in People pdf icon[186 KB, 4 pages]

Background

Influenza A viruses circulating in swine that have infected humans are referred to as “variant” viruses and denoted with a letter “v”. Human infections with H1N1v, H3N2v and H1N2v viruses have been detected in the United States.

Most commonly, human infections with variant viruses occur in people with exposure to infected swine (e.g., children near swine at a fair or workers in the swine industry). There have been documented cases of multiple people becoming sick after exposure to one or more infected swine and rare cases of limited spread of variant influenza viruses from person-to-person. The vast majority of human infections with variant influenza viruses do not result in person-to-person spread. However, each human infection with a swine influenza virus should be fully investigated to be sure that such viruses are not spreading in an efficient and ongoing way in humans and, if infected animals are identified, to limit further exposure of humans to these animals.