3 August 2012 - Update number 165
• Most countries in the northern temperate zone have stopped weekly reporting or moved over to out of season surveillance schedules.
• In the tropical zone, the countries to report notable influenza activity are Brazil, Cuba, Ecuador, El Salvador and Panama in the Americas (influenza A(H1N1)pdm09 and type B); Ghana and Madagascar in sub-Saharan Africa (influenza A(H3N2); southern China, Singapore and Viet Nam in Asia (A(H3N2) in China and Viet Nam, A(H3N2), A(H1N1)pdm09, and B in Singapore).
• The influenza season has continued in most temperate countries of the southern hemisphere for which there is data and appears to have peaked in Chile and South Africa, where many indicators have recently begun to decline. In contrast, very low numbers of detections have been reported throughout the last several weeks in Argentina. Rates of disease have continued to increase across Australia and New Zealand.
• Influenza A(H3N2) viruses were the most commonly reported type/sub-type in recent weeks across the Southern Hemisphere temperate region in Chile, South Africa, Australia, and New Zealand. However, the distribution is not uniform across Australia where influenza type B accounts for a significant portion of viruses detected in the Western Australia, Northern Territory, and Queensland. Influenza A(H1N1)pdm09 is the most common influenza virus detected in Paraguay as well as neighboring areas of southern Brazil and the Plurinational State of Bolivia.
Source of data
The Global Influenza Programme monitors influenza activity worldwide and publishes an update every two weeks.
The updates are based on available epidemiological and virological data sources, including FluNet (reported by the Global Influenza Surveillance and Response System) and influenza reports from WHO Regional Offices and Member States. Completeness can vary among updates due to availability and quality of data available at the time when the update is developed.