How many H1N1 illnesses and hospitalizations did the CDC estimate occurred in the United States?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Caring for flu victims — influenza pandemic (H1N1) of 2009 Doctors at the Mexico City Navy Hospital wearing protective gear as they tend to patients complaining of H1N1 flu-like symptoms.

To accurately reflect the impact of the 2009 H1N1 pandemic in the United States, the Centers for Disease Control and Prevention (CDC) adjusted its methodology to account for individuals who did not seek medical care or undergo laboratory testing.1

Based on these adjusted estimates for the period from April 2009 through mid-April 2010, the CDC reported the following figures for the United States:

Illnesses (Cases): Between 43 million and 89 million1
Hospitalizations: Between 195,000 and 403,0001

These estimates provided a more comprehensive assessment of the pandemic's reach than earlier tracking methods, which relied solely on laboratory-confirmed cases.1