Weekly updates, Influenza Epidemiological Week 22 (9 June 2023)

North America: Influenza activity has remained at low levels. During the last 4 EW, the predominant influenza viruses have been B/Victoria, with also circulation of influenza A (mostly A(H1N1)pdm09) at a lesser extent. Respiratory Syncytial Virus (RSV) activity has remained at low levels. SARS-CoV-2 activity has decreased however it continues circulating at moderate levels. SARI and ILI cases showed a decreasing trend, being most cases due to SARS-CoV-2 and at a lesser extent influenza.

Caribbean: Influenza activity has shown a decreasing trend. During the last 4 EW, the predominant influenza viruses have been B/Victoria, with less circulation of influenza A (mostly A(H1N1)pdm09). RSV activity has remained low. SARS-CoV-2 activity has shown an increase in the past 4 EWs circulating at moderate levels. SARI and ILI activity has shown a slight increase due to SARSCoV- 2 positive cases.

Central America: Influenza activity has shown an increase in the past 4 EWs with high levels of circulation. During the last 4 EW, the predominant influenza viruses have been A, mostly A(H1N1)pdm09, with co-circulation on influenza A(H3N2) and influenza B/Victoria. RSV activity has remained low. SARS-CoV-2 activity has remained low and has decreased in recent weeks. SARI and ILI activity has remained low, with most cases related to influenza and SARS-CoV-2.

Andean: Influenza activity has shown a decrease in the past 4 EW, although the number of influenza detections remains high. During the last 4 EWs the predominant influenza viruses have been influenza A, mostly A(H1N1)pdm09, with less circulation of influenza B /Victoria. RSV activity remained at medium levels of circulation. SARS-CoV-2 has circulated at moderate levels. SARI activity has shown a decrease in the last EWs, with influenza and RSV accounting for the majority of the cases. ILI activity has shown a decreasing trend with most cases related to influenza.

Brazil and Southern Cone: Influenza activity has decreased to moderate levels of circulation. Over the past 4 EWs, the predominant influenza viruses have been mostly A(H1N1)pdm09, with simultaneous circulation of influenza B/Victoria. RSV activity has remained steady at moderate levels during the same period. SARS-CoV-2 activity has remained low. Following a peak, both SARI and ILI activity have declined in the last 4EWs, primarily due to cases associated with RSV and influenza. In Chile, extraordinary levels of ILI activity have been observed, with the majority of cases linked to RSV and influenza. Moderate levels of SARI activity have also been detected in Chile, with RSV being the most common cause among positive cases. In Paraguay, high levels of SARI activity have been observed, with RSV being the primary cause of positive cases, followed by influenza and SARS-CoV-2 to a lesser extent.