Science Buddies: "Ask an Expert"

Hi,
I have been researching influenza viruses and I am wondering how scientists use genetic fragments to make flu vaccines. I am wondering, because some vaccine strands are identical to their virus counterparts and some are less similar. Also, how come some seasons do not have a new flu vaccine?








Thanks,
Adam

Hi Adam,

You ask some excellent questions. Are you doing this fascinating Science Buddies project? https://www.sciencebuddies.org/science- ... p003.shtml

To understand how scientists make flu vaccines, I recommend doing some research online. I typed "engineering flu vaccine" into Google, and got several good hits. You could try other search terms like "flu vaccine genetics" and others.

Here is a news article about how scientists design flu vaccines: http://news.rice.edu/2009/03/17/better- ... accines-2/
Here is an abstract to a scientific article about the use of reverse genetics in making flu vaccines: http://www.ncbi.nlm.nih.gov/pubmed/15298174

The rate at which the flu vaccine needs to change is dependent upon the rate at which the flu viruses evolve. If no new viruses evolve between seasons, or the vaccine already contains antigens for all the strains out there, we don't necessarily need a new vaccine.

Make sure you understand a bit about how the immune system attacks viruses, including the terms "antigen," "antibody," and "pathogen."

I hope that helps. Please post again (in this same thread) if you have more questions about your project.

Heather

Thank you Heather. Yes I am. I wanted to ask you something else. On the BLAST website, when I was searching for the hemagglutinin and neuraminidase forms of strains of flu virus, I noticed that there were several forms for the strains. I am curious as to why this is the case. Thank you.










Adam

Hi Adam,

Make sure you read the Introduction of the background section of the project very carefully (https://www.sciencebuddies.org/science- ... background). Hemagglutinin and neuraminidase are proteins expressed on the surface of the virus. These are what can be recognized by the immune system, and they are what scientists use to engineer flu vaccines. Small changes in these proteins allow the virus to evolve and stay ahead of the immune system. These changes and differences are what you will be comparing among the strains.

I hope that helps!

Heather

Hello there,

To add on to what Heather had already provided for you (which is all really great advice), here are some super helpful resources on the CDC about how they design flu vaccines and how they determine whether the vaccine they design each year is "effective". You should definitely take a look at these, and they may answer a lot of the questions you have!

http://www.cdc.gov/flu/professionals/va ... irusqa.htm

Let us know if you have more questions!

Best,
Connie