The CDC recommends a flu shot every season because the body's immune response declines and needs to be improved every year.
"Influenza is an unpredictable infectious disease", said Dr. William Schaffner, professor of preventive medicine at Vanderbilt University School of Medicine. There are many cases that go undiagnosed. "But it could change".
Herlihy said that makes it all the more important for people to get vaccinated this year. The virus lives longer in the cold weather because there is less humidity in the air to kill it. People can inhale the flu or get it by touching everyday objects such as doorknobs, chairs, tables and many other objects.
Flu vaccines are created to trigger the development of antibodies in charge of protecting an individual against infection with the viruses contained in the shot.
"The flu vaccine is the best way to prevent serious illness and help stop the spread of the flu, especially for vulnerable populations like young children and people 65 and older", said Cohen.
People with respiratory diseases like COPD, emphysema or asthma are seven times more likely to die if they catch flu, and people with cardiovascular problems like chronic heart disease or angina, or have had a stroke, are 11 times more likely compared to those who don't.
The 2016-17 flu season saw 87 fatalities in the county, including two children. The state's influenza surveillance system does not specifically track deaths of adults, Herlihy said.
Without having a swab test done, there isn't a sure way to tell if you have the flu.
One can't get the flu from the flu shot.
But Australia had a particularly rough flu season this year - during the Northern Hemisphere summer - putting national health officials here on guard.
The vaccine protects you from the threatening complications.
NHS England has set aside £10m to ensure care home workers get a free injection this year. According to CDC, the yearly flu vaccine is the first and most important step in guarding yourself against the flu viruses.