This Year ’s Flu Shot Was Far More Effective Than Last Year’s. Here’s Why

The 2018-2019 flu season has been a relatively mild one — and a pretty effective flu shot is part of the reason why. Mid-season estimates suggest that the flu shot has reduced the risk of illness by around 47% in vaccinated people, according to a report from the Centers for Disease Control and Prevention (CDC) released Thursday. During the severe 2017-2018 flu season, vaccine efficacy was estimated at just 36%. The difference is partly because the dominant influenza virus last year, H3N2, is known to cause more serious illnesses and to be less responsive to vaccination than other strains. This year, H1N1 — which is more easily targeted by the flu shot — has been circulating most widely, leading to less-severe and fewer illnesses overall. The CDC estimates that the flu shot reduced the risk of H1N1 infection by about 46% among adults, and about 62% among children ages six months to 17 years old. The shot’s effectiveness — and higher-than-average early-season vaccination rates — have contributed to a comparably mild flu season this year. But activity began picking up in January and is expected to continue for “several more weeks,” the CDC says. As of early February, about 4.3% of outpatient medical visits in the U.S. were due to influenza-like illness, according to the CDC. At this time during the 2017-2018 season, 7.7% of outpatient medical visits were caused by the flu. Flu- and pneumonia-related deaths have also been less comm...
Source: TIME: Health - Category: Consumer Health News Authors: Tags: Uncategorized healthytime public health Source Type: news