Wednesday, October 9, 2013

5 things people say when they don't want a flu shot. . .and why they might be both right and wrong.

 Ah, 'tis the season. That time of year when leaves begin to fall, jackets come out of hiding, noses start running, and patients either beg for a flu vaccine or literally sprint out of the office in a mad hurry when offered one.

Such a bizarre dichotomy in the land of the seasonal flu vaccine: people are either vehement defenders or adamant disbelievers. (It reminds me of the Divine and Santa Claus). Which category do you fall into? Is one group more right? Should healthy people get the flu shot?

Do flu shots cause the flu? 12 influenza vaccine myths busted
As usual, in medicine, there is no perfectly perfect answer to these questions, so I thought I would address the top 5 reasons my patients give me for declining the flu vaccine. Hopefully, you will learn something from the process. I definitely did.

1) "The flu is no big deal."
There are two problems with this argument: semantics and reality.

Semantics.  People are often confusing common colds (a slew of  mild to moderate upper respiratory illnesses that feature runny nose, cough, fevers, and more) and the real deal flu (a super serious upper respiratory infection caused by a specific virus that circulates seasonally).

And how we talk about them is a big part of the problem. After all, "the flu" is a phrase that we use in quotidian conversation with some frequency and, often,  inaccuracy. We call winter "cold and flu season"; over-the counter medicines advertise themselves "for symptoms of cold and flu", people say things like, "gosh, I just got over a horrible flu";  and  in many languages and cultures, there is little vocabulary distinction between the words for "a cold" and the words for the real "flu".   Personally, I trip over my words with my Spanish-speaking patients, never quite sure I should actually be using the Spanish word "gripe" when talking about a common cold, though my patients often do.

But, please hear this: "the real deal flu" is not the same as "a cold".

People get colds all the time. My 3-year-old is on his third this month, having lovingly shared his most recent virus with my husband, mother-in-law, and our dear neighbor. (Thankfully and unbelievably he did not share with me, in spite of the large bucketfuls of snot I have wiped from his nose). And, though colds are pesky and annoying,  most of us would probably agree that they are hardly serious.

There are over 200 viruses that cause the common cold, including the rhinovirus, adenovirus, coronavirus, parainfluenza virus, respiratory synctial virus, and 195 more. That's one of the reason you can get cold after cold. In contrast, the real deal, "the flu" (aka influenza) is caused by a specific set of viruses called-- drum roll please-- the influenza viruses (I know, I know, we doctors are clever). These are totally different viruses than the viruses that cause the common cold, and they are much meaner.

Reality. Putting common colds aside, the flu is actually a pretty big deal. In fact, the influenza pandemic of 1918-19 killed between 20 and 40 million people, more people than World War I-- perhaps the most devastating epidemic in recorded world history. Thankfully, we have not had a flu epidemic as serious since then; however, there is still no cure for influenza, and plenty of  people do die from the flu each year.

The Centers for Disease Control (CDC) estimate that between 1976 and 2007, between 3,000 and 49,000 people each year died of the flu. The range is crazy big for two reasons: first, it's hard to figure out how many actually people die of the flu and second, each flu season varies intrinsically. Some years are bad years, others are good.

On average each year in the US, 200,000 people are hospitalized as a direct result of the flu. People 85 and older are at the highest risk of being hospitalized. The other high risk groups are children younger than 5 (especially those younger than 2), adults over 65, pregnant women, and American Indians and Alaskan Natives. Also at risk are people with asthma, chronic lung and heart disease and a whole list of other chronic health conditions.

For those of us who don't die, getting the flu still knocks us down. Big time. A study published in 2007, estimated that seasonal flu epidemic results in 3.1 million hospitalized days, and 31.4 million clinic visits (that's a lot of business for me and a lot of sick-time, co-pays, and stress for you all). Direct medical costs average $10.4 billion annually, and projected lost earnings due to illness and loss of life was $16.3 billion per year. In this study, the total economic burden of seasonal flu epidemics amounted to $87.1 billion.

No big deal?

2) "That flu shot does nothing to protect me, I still always get sick all winter long. I don't think it works."
You are right.

Winter is a germy time of year and, as alluded to above, the flu shot does absolutely squat (i.e. nothing) to protect you from the common cold. That is not its job.

The average preschooler gets 9 colds per year, the average kindergartner 12, and the average teenager and adult 7. Most of these occur between November and March. Yuck! And though colds and the flu are two different entities entirely, the flu and the common cold have a lot in common: both are spread by droplets, both are caused by viruses, both are present during this time of year, and people with colds often have "flu-like" symptoms.

So, how are you supposed to know the difference?

Really the best way to know whether or not you have the real flu is by getting tested (it's done by a nasty swab in your nose), but not everyone gets tested. Personally, I favor my mom's classic description of influenza: "When you have the flu, you literally cannot stand up. You literally have to lie down and stay in bed. And it lasts a good long time. A week, usually. Your body aches, your fever is high, and you feel like crap." (Mom doesn't use the word 'crap', that's my addition to her definition).

Most people cannot tell me that they feel that bad (or feel that bad for that long) when they get a cold--even a bad bad cold. 
Courtesy: Artville - Whitney Sherman

3) "I have never had the flu up 'til now. Seems like I just don't need the shot."
It is true, statistically-speaking, that most people will not get the flu in a given year. And though the pro-vaccine propaganda professes that getting a flu shot decreases your risk of the flu by 60%, the number is definitely misleading. The reason is this: this widely quoted percentage doesn't give any information about how likely it is that you will get the flu in the first place; it only tells you how much the flu vaccine will reduce your relative risk of getting the flu. Welcome to absolute versus relative risk reduction, two of the trickiest concepts in medicine.

Unlike the common cold, your risk of actually getting the flu is pretty low-- it's about 7% per year. That's why many of you have never had the flu. The flu vaccine reduces that risk down to 1.9%. This translates statistically into a 60% relative risk reduction but in actual terms is only a 5% reduction. Does 7% risk seem high or low to you? What about 1.9%, does that seem like a reasonable reduction?

Those of you who play the flu lottery and assume you won't get sick will be right 93% of the time, even if you are never vaccinated. Acceptance of risk is tricky and personal. We've hit on that notion before when talking about breast cancer screening, lung cancer screening, and car seats. It's your call to make.

The question to ask yourself is this: on the off chance that you are one of the 7%, who actually gets the flu, how horrible would the flu be (in addition to the inevitable fever, body aches, and general malaise)? Would missing work threaten your job security or make it impossible for you to pay your rent? Are there loved ones under 5 over 65 who could get really sick if you shared your influenza? Do you work with frail seniors who are at the highest risk of dying from the flu? Do you have a young vulnerable niece or nephew? Do you just prefer to be safer than sorry? Or does that flu shot hurt too much to be worth the risk?

4) "I got the flu shot last year and got the flu anyway, so why bother?"
 This is some of the most interesting part of the flu vaccine story. Did you know every year the vaccine is different? Each year there is a statistical modelling done by the World Health Organization (WHO) and scientists around the world to try to guess which will be the dominant influenza strains that year.

More than 100 centers in more than 100 countries do year-round surveillance for influenza. These centers receive and test thousands of influenza virus samples from patients with suspected flu illness. Then, the viruses are sent to five WHO Collaborating Centers located in Atlanta, London, Melbourne, Tokyo, and Beijing.

In February of each year, WHO consults with experts from these labs and other partners to review data generated by the worldwide network of influenza laboratories. Afterward, WHO makes recommendations for the what should go into the seasonal influenza vaccine for the Northern Hemisphere. For the Southern Hemisphere, the same groups meet in September.

Some years, the "match" is better than others. . .
See here  and here for more details from the CDC.

5) "That flu shot gives me the flu every time."
Impossible, mostly.

The injectable flu vaccine is dead vaccine. You cannot, I repeat can NOT, get the flu from the vaccine. You can get a really sore arm (I always do, along with 64% of people). And about 1% of people get fever, malaise, muscle pain and a general sense of feeling yucky (this is more common in kids who've never been exposed). They might interpret this as "getting the flu", but it's not nearly as bad. Believe me.

The caveat is this: the intranasal vaccine (for those of us who don't like needles) is a live attenuated vaccine, which in theory, means there is a risk of actually getting the flu from the vaccine. Big population studies have not shown this to be true. There is evidence that people who get the live vaccine can shed the virus, but these viruses are pretty close to dead and unlikely to make another person sick. We still don't give this vaccine to people who have chronic diseases-- it's licensed for "healthy people" ages 2-49. The advantage? No needle stick, just a weird sensation up your nose.

So, what do you think? Are you a vehement defender or an adamant disbeliever? 


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