When is flu season 2018

Health Tools. Flu The Impact of Influenza: The — Flu Season and Years of Pandemics The — flu season — one of the longest flu seasons on record — marked the th anniversary of the Spanish flu pandemic. Facebook Twitter Pinterest Copy Link. Reviewed: October 7, Medically Reviewed. Follow these steps to keep yourself — and those around you — protected from the flu. Wash your hands regularly with soap and water. Avoid close contact with people who are sick.

Cover your mouth when coughing or sneezing. But the length and trajectory of the most recent flu season—which began in November, peaked in mid-February and trailed off in April—was unique, the CDC says. Most flu seasons start off with lots of infections from influenza A viruses, which can be more severe and less responsive to vaccination than other subtypes, while generally less-severe influenza B viruses often strike later.

But this year, the CDC says, two different phases of influenza A activity dominated the season, contributing to its unusual length. H1N1 circulated widely from October to mid-February, then H3N2 picked up from mid-February into the spring, according to the new report. Even still, high early-season vaccination rates and a relatively effective annual vaccine appeared to help suppress illnesses. In total, the CDC estimates that up to The report documents that there were 2 notable waves of influenza A activity: from October to mid-February there was an influx of the A H1N1 pdm09 cases and from mid-February to mid-May there was an increase in A H3N2 cases.

Influenza B subtypes were available for Most of the A H1N1 pdm09 viruses were antigenically similar to the cell culture-propagated reference virus representing the Northern Hemisphere influenza vaccine virus, but considerable genetic diversity among currently circulating A H1N1 pdm09 viruses belonging to clade 6B,1A was observed.

Additionally, the increased circulation of clade 3C. The investigators also noted that the severity assessment was moderate across all age groups. The rate of hospitalization was lower for adults compared with the influenza season, but similar for children.