H1N1 Flu

Novel 2009 H1N1 Flu: International Situation Update

August 21, 2009, 11:00 AM ET

Map of International Activity Estimates
(Including 2009 H1N1 Flu)

This situation report provides an update to the international situation as of August 21, 2009. As of August 13, the World Health Organization (WHO) regions have reported over 182,166 laboratory-confirmed cases of 2009 H1N1 influenza virus (2009 H1N1) with 1,799 deaths. The laboratory-confirmed cases represent an underestimation of total cases in the world as many countries now focus surveillance and laboratory testing only in persons with severe illness. The 2009 H1N1 influenza virus continues to be the dominant influenza virus in circulation in the world. Decreases in disease due to 2009 H1N1 continue to be reported from South America and parts of Australia. The United Kingdom is also reporting national decreases in disease due to 2009 H1N1. In contrast, disease associated with 2009 H1N1 influenza is continuing to increase in southern Africa and more Africa countries have reported their first cases. In addition, 2009 H1N1 continues to circulate in tropical countries.

Selected Highlights

The 2009 H1N1 influenza virus is the predominant influenza virus in circulation worldwide.
The epidemiology of the disease caused by the 2009 H1N1 influenza virus in the Southern Hemisphere is very similar to that described in the United States this past spring.
There have been no significant changes detected in the 2009 H1N1 influenza virus isolated from persons in the Southern Hemisphere as compared to viruses isolated from persons in the Northern Hemisphere.

International Resources for 2009 H1N1 Information

Health Organizations

World Health Organization (WHO) Regional Offices

Travel and 2009 H1N1 Flu

Human cases of 2009 H1N1 flu virus infection have been identified in the United States and several countries around the world. For information on 2009 H1N1 flu and travel, see the CDC H1N1 Flu and Travel website.

Reports and Publications

ECDC Interim Risk Assessment Influenza A (H1N1) 2009 Pandemic
Issued July 30, 2009 - This document provides an interim risk assessment of novel H1N1 flu in Europe prepared by ECDC.
World Health Organization Weekly Epidemiological record – Issued July 24, 2009
This document by WHO provides updates on the international novel H1N1 flu situation.
MMWR – Update: Novel Influenza A (H1N1) Virus Infection – Mexico, March-May, 2009 – Issued June 5, 2009 / Vol. 58 / No. 21.
This Morbidity and Mortality Weekly Report describes the novel influenza A (H1N1) outbreak in Mexico from March-May, 2009.
MMWR – Update: Novel Influenza A (H1N1) Virus Infections – Worldwide, May 6, 2009 – Issued May 8, 2009 / Vol. 58 / No. 17.
This Morbidity and Mortality Weekly Report describes worldwide novel influenza A (H1N1) infections as of May 6, 2009.

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