Content on this page was developed during the 2009-2010 H1N1 pandemic and has not been updated.
- The H1N1 virus that caused that pandemic is now a regular human flu virus and continues to circulate seasonally worldwide.
- The English language content on this website is being archived for historic and reference purposes only.
- For current, updated information on seasonal flu, including information about H1N1, see the CDC Seasonal Flu website.
2009 H1N1 Flu May Be More Serious for Some
December 5, 2009, 6:00 AM ET
Most people have been able to recover at home from 2009 H1N1 and seasonal flu without needing medical care. However, the flu can be more serious for some people.
People at High Risk for Developing Flu-Related Complications
- Children younger than 5, but especially children younger than 2 years old
- Adults 65 years of age and older
- Pregnant women
- People who have medical conditions including:
- Neurological and neurodevelopmental conditions [including disorders of the brain, spinal cord, peripheral nerve, and muscle such as cerebral palsy, epilepsy (seizure disorders), stroke, intellectual disability (mental retardation), moderate to severe developmental delay, muscular dystrophy, or spinal cord injury].
- Chronic lung disease (such as chronic obstructive pulmonary disease [COPD] and cystic fibrosis
- Heart disease (such as congenital heart disease, congestive heart failure and coronary artery disease)
- Blood disorders (such as sickle cell disease)
- Endocrine disorders (such as diabetes mellitus)
- Kidney disorders
- Liver disorders
- Metabolic disorders (such as inherited metabolic disorders and mitochondrial disorders)
- Weakened immune system due to disease or medication (such as people with HIV or AIDs, or cancer, or those on chronic steroids)
- People younger than 19 years of age who are receiving long-term aspirin therapy
If you have flu symptoms and are also in one of the above groups, call the doctor. Your doctor may prescribe medicines that can make your illness milder and make you feel better faster. They may also prevent serious flu complications.
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