Although the flu season generally runs from October through May, Lee Health Epidemiology & Infection Prevention System Director Stephen A. Streed said last year the flu season did not ramp up locally until January.

“It starts circulating in the fall and winter,” he said because an influx of people from various parts of the country begin arriving in Southwest Florida. “Sometimes they bring with them an active infection and develop influenza.”

The best protection against the flu – a contagious respiratory illness that infects the nose, throat and lungs – he said is getting the annual shot. The vaccination provides six months of protection, which covers the length of the flu season.

“It has four of the strains of the flu virus that will most likely circulate,” Streed said.

Although the vaccine is made months in advance before flu season begins, the strains are created from monitoring influenza around the world. He said the strains, typically labeled as influenza A and B, are usually named after the locality of where the flu popped up.

The Centers for Disease Control and Prevention monitors the frequency of those strains, following how it moves around the world and the likelihood of it being introduced to North America.

“There are four different strains in this year’s vaccine. Two As and two B strains,” he said. “Like so many other diseases when you have widespread vaccine coverage, the disease can’t propagate in a group.”

Herd immunity, which he explained happens when there are enough people vaccinated stopping the disease from propagating.

“The shot is not a live virus. It’s a kill virus. It can’t give you the flu,” Streed said. “You can’t get sick from a virus that is dead.”

The vaccination can sometimes have a local reaction, soreness, joint pain and inflammation around the injection point. The joint pain associated with the shot is the immune system reacting to the vaccination.

“I think it is very important societally, that when we have a condition we can prevent, we ought to do that,” Streed said of getting the vaccination. “If one out of 100 is hospitalized, that is way too many.”

Lee Health in past years have seen anywhere from 200 to 300 cases throughout the system on a bad week during flu season.