What symptoms were common in people infected with the 2009 H1N1 virus?

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Individuals infected with the 2009 H1N1 virus typically experienced fever and mild respiratory symptoms, such as coughing, a runny nose, and congestion.1

In some instances, symptoms were more severe and included:
* Chills1
* Diarrhea1
* Vomiting1

In rare cases, infected individuals experienced respiratory failure. The virus was found to be most lethal in people who had underlying health conditions or chronic diseases.1