Experts say it is highly contagious, and it only takes a small amount of the virus to infect a person. 

Last year, Kentucky saw a spike in illnesses between October and early January.

The approval comes as the nation faces the largest summer wave of COVID-19 cases in two years.

Norton Children's pediatrician Dr. Amael Shalash said there have been more than a thousand flu cases system-wide this month.

Flu cases are up over 15% while COVID-19 cases are down around 5% in Kentucky, according to data from the last week of 2023.

After large gatherings around the holidays, Louisville doctors are noticing a spike in COVID, flu, RSV and strep throat cases. 

As the weather gets colder, one Louisville doctor said more people are gathering with folks indoors.

Respiratory illnesses like COVID, RSV the flu and even some unnamed viruses are on the rise nationwide.

RSV is running rampant in Kentucky, infecting infants, kids and adults in record numbers.