Skip to main content

ASU researcher debunks flu shot myths

Does the vaccine work by making you sick? How long does it last? A Biodesign Institute professor explains it all

July 07, 2016

The fall semester is approaching fast, and so is flu season. Arizona State University employees are eligible for free flu shots in October, but there are several misconceptions about the vaccine — and the flu, itself.  

Karen Kibler, an assistant research professor in ASU’s Biodesign Institute, sorts out the myths and facts.

Question: Is it true that the vaccine works by getting you sick?

Answer: Well, there’s a long answer to that. There are two forms of the vaccine. Maybe you’ve seen the kind that you spray into your nose? That one is a live, attenuated vaccine. Now that means that in the lab, with genetic mechanisms, we can make the virus weaker. So it’s not like the flu that’s out there and infects you. It’s different. It’s modified. But it is able to replicate. Maybe not in a normal healthy person, because that’s why we make it weak, but for instance, if someone is immune compromised and they don’t realize it, then that live vaccine is contraindicated. And it’s always important to speak to a doctor before you have that vaccine.

The shot, there’s no living virus in the shot. It’s an inactivated vaccine. So the ways that viruses are inactivated are with heat, with radiation or chemicals. So it’s dead. It’s really just a little pile of proteins.

And that brings me to the next step in this: the proteins — whether it’s a natural infection or live vaccine or dead vaccine — it’s those proteins that our immune system recognizes as foreign. So the immune system sees those proteins and puts into gear all its antiviral defense systems. And part of that system will produce a substance called interferon. And interferon makes you feel awful. Kind of yucky. So sometimes people are feeling the effects of interferon, and they think they’re sick with the virus. It’s actually a sign that your immune system is working very well, it’s mounting a defense against these proteins. But the really critical part of the vaccine is that whether it’s a natural infection or a vaccine, the same mechanism takes place: When the immune system sees those proteins, it starts producing memory cells. And those cells will stay with you for a very long time. So those memory cells are what are really important, because the next time you’re with some people and you get exposed to the flu virus and the virus gets inside you … the memory cells respond within one to three days. That’s a really quick response. You won’t even know you were infected by the virus because your immune system will kill it off so fast. Now, the beauty of the vaccine is that the same thing happens when you get a natural infection, but you have to go through the whole infection to get to the point of the protection. So what a vaccine does, is give you that same exposure to the proteins, but in a much safer, a much more controlled way, and you don’t have to go through two weeks of illness to get the protection for the next time.

Q: What’s the time frame for the immunity? Around a year or so?

A: Well, the reason we have to be revaccinated with flu is that the flu changes constantly, it mutates and becomes different. Eventually, its proteins don’t look like the proteins your immune system saw the year before, and they don’t recognize the new ones. So they have to start all over in creating memory cells, and those memory cells take about 30 days. So by the time you’ve made memory cells, you’re past the infection, if you got a natural infection. And that’s why every year, some really incredible people take a look at all the flu viruses around the world and they try to figure out which strains of which subspecies, which virus’s versions of the virus are going to be around in six months, because it takes six months to make all those vaccines, the vaccination injections. So they try to figure out which one is going to be most prevalent, and that’s what they base the vaccine on.

Now, the vaccine actually covers three flu viruses, and there are vaccines that cover four. So they do their best — there have been a few years that the virus changed and went in a different direction and the vaccine wasn’t as effective. It’s always going to help some, because the whole virus doesn’t change. There are two primary proteins in the flu virus that are what the immune system recognizes, and those can change somewhat. And even if they change a little bit, they’re not completely different — it’s not like a horse becoming a dog. So your immune system is still helpful. You probably will get less sick, even if the vaccine doesn’t cover it as effectively as it might have the year before.

Q: I’ve also heard if you get the virus or vaccine, you’re done — you don’t have anything to worry about, and you’re completely safe.

A: That is not true. Sometimes a person’s immune system just isn’t as healthy. You may not be immune compromised, but maybe your immune system isn’t quite as active as someone else’s, so it maybe kind of sloughs off on producing the memory cells. Usually, if you’ve been vaccinated and get the flu, it’s because the virus that infected you just looks too much different from the one that was in the vaccine. And that’s why they try really hard to anticipate which versions of the virus will be most commonly around. And there will always be odd ones, and sometimes people are just the unfortunate ones who get infected with that really odd version, and it’s not covered by the vaccine.

Q: So what precautions you can take to try and make sure you lessen the risk of catching the virus?

A: Washing hands constantly is the biggest thing. And it’s reflex for me and many people who are virologists. Never cough and sneeze into your hands, because your hands touch everything. Now, the viruses don’t survive indefinitely on the surface, but when we’re in close proximity with other people, we touch so many things, we touch our faces — somebody did a study on this and it was something like 1,000 times a day we touch our faces. So if you have viruses and they get anywhere near your mouth or eyes or nose, they’re going to get inside. If you sneeze and you’re infected and you touch surfaces and someone else comes along and touches surfaces, that’s how it spreads most quickly. It’s really important to not let anything be on your hands. So if you have to touch surfaces where other people are, then you wash your hands. If you are the one who’s sick, you don’t touch surfaces unless you absolutely have to, and if you do you wash your hands before you do that. But unless there’s a medical reason to not be vaccinated, everyone should be vaccinated.

Q: So when you mention places where we’re in close proximity with other people, dorms, universities…

A: Yes, universities are terrible! (Laughs.) Schools, elementary schools, kids tend to be less careful about hygiene than adults, though sometimes college students aren’t too much different. How many students sit in the same desks and touch the same doorknobs and the same bathroom doors? And the faucets. And the drinking fountains. And the same computers. The list goes on and on.

Q: So what makes the flu season, the flu season in the first place? Why are people more susceptible to viruses in these fall and winter months?

It does tend to be the fall and winter months, but not because it’s cold outside — although it is kind of side effect of that — your nasal passages tend to get a little bit drier during the fall and winter. The natural means of keeping particles out of your respiratory system isn’t as effective. So you’re more likely to inhale some viruses. And that’s true with the flu and cold viruses.

Q: What are some common myths or stories you’ve heard about the flu?

A: As an instructor I was often told by students, “I’d rather just get sick then get the vaccination.” Because they figure they could try to avoid it and if they get sick, so what, they could just tough it out. And the problem with that, is that there are people who cannot get vaccinated. There are children too young, there are the elderly — their immune systems don’t work well, vaccinations aren’t nearly as effective in the elderly, and they die very quickly from the flu infection. There are people HIV infected, people on chemotherapy, people with organ transplants. They’re so fragile when it comes to the immune system. So if you aren’t vaccinated as a young, healthy person that can tough it out, even though we could probably get through it, if you give it to someone who can’t, that person might die from it. More than 35,000 people in just the United States die each year from flu infection. I think of this as a community responsibility.

Q: Do you have any additional information about the flu’s symptoms?

A: You know, I would much rather refer you to a website. The Centers for Disease Control (CDC) has a great flu section, as well as the Mayo Clinic and the World Health Organization (WHO), if you’re interested in worldwide.

ASU employees can receive the flu vaccine at these locations during the month of October:

West campus

10 a.m.-1 p.m., Monday, Oct. 3, UCB La Sala A

Tempe campus

7 a.m.-4 p.m., Tuesday-Thursday, Oct. 4-6, MU 228

Downtown Phoenix campus

8 a.m.-noon, Tuesday, Oct. 11, UCENT 580 A

Polytechnic campus

10 a.m.-1 p.m., Wednesday, Oct. 12, Student Union, Cooley BR A

All benefits-eligible ASU employees are welcome. Non-benefits-eligible employees can also receive flu shots, but they will cost $20, payable in cash or by check only. (Employees' family members, retirees, student employees, graduate assistants and other students are not eligible to receive a shot through this program.)

To receive a free flu shot you will need:

• a valid state-issued (Arizona) employee insurance card (if you are benefits-eligible and do not have insurance through ASU, just bring your Sun Card)

• a valid ASU Sun Card

There are no exceptions to these requirements. Shots will be given on a first-come, first-served basis for as long as the supply lasts.

More Science and technology


A group of people posing around the Arizona State University sign on the ASU Tempe campus with Old Main building in the background

ASU expands hands-on lab opportunities for online biochemistry students

As a New York City autopsy research coordinator, Stephanie McQuillan saw her continued education as a gateway for career advancement. Juggling full-time work in New York, McQuillan thrived in the…

Headshot of Petr Sulc

Blueprints of self-assembly: New design technique advances nanotechnology

Many biological structures of impressive beauty and sophistication arise through processes of self-assembly. Indeed, the natural world is teeming with intricate and useful forms that come together…

Three people sit at a table signing documents

ASU assists Panamanian microelectronics development efforts

Arizona State University continues to expand its efforts to support the development of the semiconductor workforce and supply chain on a global scale. On April 30, Panamanian President Laurentino…