Northern Hemisphere: Influenza Season Almost Over

In the U.S., the main influenza season is almost over, with the proportion of outpatient visits for influenza-like illness (ILI) in the most recent week at 2.7%, following 17 consecutive weeks above the national baseline of 2.2%; ILI peaked at 7.5% in early February. Influenza B continues to predominate over influenza A, a typical occurrence late in the influenza season. Currently, only 6 states are experiencing high ILI activity. Pneumonia and influenza mortality rates have nearly returned to baseline. In Canada, ILI rates have decreased below the 5-year average, and influenza B continues to predominate over influenza A. Influenza activity has peaked throughout most of Europe, with equal proportions of influenza A and B (almost exclusively B/Yamagata) being reported. It's still ideal for seasonal influenza vaccination for all travelers and oseltamivir as standby therapy, especially for those who are at high risk for complications from influenza or who are inadequately vaccinated. Antiviral treatment with neuraminidase inhibitors should be started as soon as possible and should not wait for laboratory confirmation of influenza.