Influenza outbreaks have almost always been a part of American history, dating back to a 1793 breakout in Vermont that affected over two million people. Some, such as the breakouts in 1918 or 2009, have been especially deadly, often coinciding with the emergence of formerly unknown strains of the virus.

In 2009, the H1N1 virus appeared for the first time, causing one of the most dangerous flu pandemics in the history of the country.

It would not be an exaggeration to say that the flu is as American as apple pie. Indeed, the Centers for Disease Control (CDC) has stated in the past that declaring the year’s flu season an epidemic is an almost annual occurrence.

That being said, the current flu season has proven especially dangerous. According to the CDC, every state except for Hawaii is experiencing widespread disease.

This makes it the busiest week for flu symptoms since the devastating 2009 outbreak, when the World Health Organization (WHO) issued their first ever declaration of a “public health emergency of international concern.”

Warning signs started to appear once Australia — whose flu season starts a few months before the American season due to the seasonal differences in hemispheres, and is often used to predict which strains will be most prevalent — announced that the year’s chosen vaccines were only 20 to 30 percent effective against the most common strain of the year, the H3N2 strain of Influenza A.

During the production of the vaccines for this season, the virus mutated in an unavoidable fashion, dramatically lowering the efficacy of the inoculation. Despite initially optimistic predictions for the season, 2017-18 is closely mirroring the 2014-15 flu season, in which the same strain had yet to peak in virality towards the end of January.

This season is also complemented by the H1N1 strain of Influenza A, an especially dangerous combination because H3N2 is incredibly dangerous for the elderly or extremely young, whereas H1N1 is very easy for a school-age child to contract.

The season’s much-discussed danger started manifesting itself early on in the year. In New York, more than 1,600 people have been hospitalized due to the flu in the last fifteen days. According to CDC Influenza director Dan Jernigan in a press briefing mid-January, the next week or two represents the peak of the season.

“We’re at the peak of it now,” Jernigan said. “We’ll probably see it go below the baseline in several months.”

Despite the low efficacy rates of vaccines, the CDC still recommends everyone get a flu vaccine if possible. The widespread rate of illness (6.3 percent visits to a health care provider being for a flu-like illness between Jan. 7 and Jan. 13, almost three times the annual average) means any form of protection is valuable.

Flu vaccines can be received from any Sutter Walk-In Care site in the Bay Area, including the Palo Alto Medical Foundation Palo Alto Center.