10/14/2013 05:05 EDT | Updated 12/14/2013 05:12 EST

Flu shot too little, too late for some

The flu vaccine is now available at doctor's offices, clinics, and some pharmacies, but for some, flu season came too soon.

Ahmed Ullah is spending Thanksgiving at a medical clinic with three sick children. 

"Last month my kid had the flu, and my wife, then me and the other kids got after. It goes around the circles in the house," he said.

Dr. Allison McGeer, an infectious disease specialist, says flu season starts as early as November and typically runs for about 12 weeks. She adds that viruses are currently going around, but influenza is more severe.

Like past years, there are three strains of influenza in the vaccine this year: H1N1, H3N2, and a B strain.

But infectious disease specialists say there are two B strains that have infected people, but only one is included in this year's shot. There is a nasal spray vaccine that covers all four strains for children, but McGeer says for adults the four-strain vaccine is only available in the United States, and only in small quantities. 

Next year's vaccine will include the two B strains of the flu. 

"People who are elderly, who are 85 or 90, and for children who haven't met much influenza before who haven't had many years to get vaccinated — that's where the extra B strain is going to help," she says.