The flu has now reached epidemic levels after the Center for Disease Control announced the entire country has high levels of the virus.
Doctors also said this year, in some cases, the flu can cause a 'storm' in your body which can potentially lead to other infections.
The CDC has declared it as an epidemic with nearly every state seeing the most hospitalizations from the flu in recent memory.
"Usually there's a few strains circulating but this year there's a primary 'a' strain and 'b' strain," said Infectious Disease Specialist Dr. Daniel Skiest at Baystate Medical Center.
The viruses in circulation can often change and sometimes the viruses have many subtypes, also changing the mutation of the virus.
"Because it's changing and mutating so the vaccine wasn't as effective it looked like as we would've hoped. It would've been, and there may be other factors that we won't learn about until later on when they go back and study this season," Dr. Skiest explained.
Doctors said another setback with the flu this year is healthier people are getting sicker if they get the flu.
Dr. Skiest told Western Mass News this happens due to something called a 'cytokine storm'.
"Cytokine's release which are these chemicals in the body and they cause inflammation and they help fight off the infection. But sometimes they sort of go too far in some patients for reasons that are unclear and can actually make you sicker for a while. That's one of the theories why some of the people that are younger could be getting sicker and having more symptoms," he added.
Dr. Skiest also noted that many still think it's too late to get a flu shot and people believe it's ineffective, but he told Western Mass News the best protection against the flu is by getting the flu shot.
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