The Centers for Disease Control and Prevention (CDC) reports:

“A few things are new this season:

• Flu vaccines are updated to better match viruses expected to be circulating in the United States.
  • The A(H1N1)pdm09 vaccine component was updated from an A/Michigan/45/2015 (H1N1)pdm09-like virus to an A/Brisbane/02/2018 (H1N1)pdm09-like virus.
  • The A(H3N2) vaccine component was updated from an A/Singapore/INFIMH-16-0019/2016 A(H3N2)-like virus to an A/Kansas/14/2017 (H3N2)-like virus.
  • Both B/Victoria and B/Yamagata virus components from the 2018-2019 flu vaccine remain the same for the 2019-2020 flu vaccine.
• All regular-dose flu shots will be quadrivalent. (No trivalent regular-dose flu shots will be available this season.) Read more here.

This Website, FluNearYou.org, tracks flu cases around the country. “Early detection and early response are key to preventing the spread of any disease. We believe that letting individuals report symptoms in real-time can complement traditional tracking while providing useful information directly to the public.”

“While seasonal influenza (flu) viruses are detected year-round in the United States, flu viruses are most common during the fall and winter. The exact timing and duration of flu seasons can vary, but influenza activity often begins to increase in October. Most of the time flu activity peaks between December and February, although activity can last as late as May.” – CDC