LITTLE ROCK, Ark. (KTHV)- The Health Department said researchers try to match the flu shot as close to the different strains as they can but this year for some reason they're not sure why it's not working as well.

The parents of Tyler Dannaway, the first child to die from the flu in Arkansas this season, still can't believe how fast it happened.

The Dannaway’s said Monday is when he started to show signs.

“He seemed sluggish and had a fever of 100.4,” they said.

They said they didn't want to take any chances, so they took him to the doctor.

“The doctor ran his temperature and came back with a temperature of 104.7,” the Dannaway’s said.

The doctor diagnosed him with the flu and his symptoms were escalating so fast; he was given breathing treatments and prescriptions for Tamiflu and Albuterol.

But Tuesday morning Tyler couldn’t walk and collapsed on the floor, his parents rushed him to the ER.

“It wasn't going well and his heart had stopped and it had been stopped for about an hour and they just couldn't resuscitate him,” they said.

The Dannaway’s said they didn't realize how fast the flu could take a life.

“From the time the whole thing started and that we knew anything was wrong was less than an hour and a half,” they said.

Scientific researchers work with labs on the national level to develop the flu vaccine each, then the information is then passed to each state. The method is a proven one. However this year the Arkansas Department of Health said preliminary information across the U.S. is showing the 2017-2018 shots are not producing as good of results as in years past.

“We really don't have good explanations for that at this time. The vaccine still works but just not as great as we would like it to,” they said.

Chief medical officer, Gary Wheeler, said the flu has been known to develop and kill within hours

“It is a little bit of an unusual event but it is does describe the influenza virus,” he said.

Chief Wheeler said no matter what, it's always best to take precautionary measures.

“We do currently continue to encourage people to get a vaccine if they're not vaccinated,” he said.

The Health Department said they’ve also had over 100 hospitalizations this flu season.