[Influenza A (H1N1). Experience in the United States]

Area of Science:

• Virology and Epidemiology
• Public Health
• Infectious Disease Outbreaks

Context:

• The 2009 H1N1 influenza A outbreak rapidly became a global pandemic.
• Influenza A (H1N1) activity exceeded previous years, with a notable impact on the pediatric population.
• Severe cases were associated with comorbidities like chronic pulmonary disease, immunosuppression, heart disease, obesity, and pregnancy.

Purpose:

• To review the North American experience of the 2009 influenza A (H1N1) pandemic.
• To provide a chronological examination of H1N1 epidemiology, high-risk groups, diagnosis, vaccination, and management.
• To analyze the substantial public health impact of the pandemic.

Summary:

• The review covers the epidemiology of the H1N1 virus, its spread, and its disproportionate effect on individuals under 18.
• It identifies key comorbid conditions associated with severe H1N1 influenza.
• The focus is on the North American response, including diagnostic and management strategies.

Impact:

• The 2009 H1N1 pandemic had significant global repercussions on mortality, morbidity, and healthcare costs.
• Understanding the pandemic's trajectory and impact is crucial for future public health preparedness.
• The review highlights the importance of targeted interventions for high-risk populations during influenza outbreaks.