The New Year is upon us and with the New Year comes an event as expected as the swallows return to Capistrano. What would that event be you ask? Well it must be Bill Tieleman’s annual articles against BC’s flu vaccination program. This year’s offerings are titled: Costly, Ineffective Flu Shots Fail Again (in the Tyee) and Flu shots fail again – at great cost – and what if all you hear is wrong? (in 24 Hrs). Last year’s offering was Time to End Expensive, Ineffective Forced Flu Shots (in the Tyee). His previous efforts including December 2014’s (Are Flu Shots as Effective as Billed?) and December 2013’s (More Evidence Against Forced Flu Shots). These are in addition to his similarly themed articles in Vancouver 24 Hrs (2013 and 2014) and his blog (Oct 2013, Dec 2013 and 2014). As I have written previously, one could almost suggest that he is a one-man content provider for the anti-flu shot brigade. Mr. Tieleman’s yearly pieces are similar in form and content and provide excellent fodder for any class studying the communication of science. As I explained last year, and will explain again this year, his articles provide excellent examples of problematic science communication and for those not able to take a science communication class, I will now examine parts of Mr. Tieleman’s latest articles for you.
Now to be honest, since he keeps repeating talking points it is only fair that I repeat a few things from my last year’s blog on the topic. Let’s start with a simple explanation of one of the critical terms used in these articles: “vaccine effectiveness”. Vaccine effectiveness is the “ability of a vaccine to prevent outcomes of interest in the real world”. To further clarify, if a vaccine has 50% effectiveness that means it reduces the likelihood of getting the flu by 50%. This does not represent a one-time deal, it is a seasonal effect. During the flu season you can be exposed to the influenza virus numerous times a day, numerous days a week, numerous weeks in the year and 50% effectiveness means that over that entire time the vaccine has reduced your likelihood of getting the flu by 50%. So let’s understand vaccine effectiveness is not some one-time event like turning the key in your ignition. Individuals are exposed to the influenza virus repeatedly over the course of the flu season.
In science communication we are always looking for good analogies. An apt analogy would involve some medical device or public safety innovation that had a comparable effectiveness in reducing a negative outcome. Happily for our discussion such an innovation exists, it is called “the seat belt”. A properly used seat belt reduces your likelihood to be injured in the event of an automobile accident. Seat belts aren’t perfect, however; and they won’t prevent all injuries. No seat belt in the world will save your life if you get t-boned by a semi but seat belts reduce serious crash-related injuries and deaths by, yes you guessed it: about 50%. Thus using the same descriptive criteria as is used for vaccines the effectiveness of seat belts would be defined as 50%. As presented by the CDC, the flu vaccine since 2004 has varied in effectiveness between 10% and 60% with an average just under 50%. Funny, I don’t see Mr. Tieleman suggesting that we should be giving up on seat belts in automobiles because they only have an effectiveness of 50%.
Now sticking with our seat belt analogy, as I pointed out above the best seat belt in the world will not save your life if you get T-boned by a semi. Similarly, the best vaccine in the world won’t work if it is designed for the wrong strain of influenza. The problem is that there is not one single human influenza virus, rather there are dozens of strain/subtype variations and experts must pick which viruses to include in the vaccine many months in advance in order for vaccine to be produced and delivered on time. Sometimes they get it wrong and like last year’s vaccine you end up with lower effectiveness. That is not a reason to abandon a good program. Even in a bad year (like 2014-2015 where we saw 23% effectiveness) the result is a substantial reduction in illness rate. This year it looks like we are going to be lucky as it appears that this year’s major strain (H3N2 a particularly virulent form) is in this year’s flu vaccine.
Going back to his standard rant, Mr. Tieleman’s talking points always seem to include a section deriding stats about the number of flu-related deaths. His lines this year:
A group called “Immunize Canada… a coalition of national non-governmental, professional, health, consumer, government and private sector organizations” — including major flu vaccine manufacturers — claims that: “Between 4,000 and 8,000 Canadians can die of influenza and its complications annually.”
Really? Because the Public Health Agency of Canada reports that in 2011-12 there were just 104 deaths; in 2012-13 deaths were 317; 331 in 2013-14; 591 in 2014-15 and 270 in 2015-16. In no year did flu fatalities approach 4,000 to 8,000.
The reason for the identified mismatch is because the flu is not the sole (or even major) cause of death in many/most cases, rather it is a contributing cause and thus the numbers do not match up perfectly. Instead public health agencies rely on regression modelling which allows scientists to peel out the effect of the influenza on increased death rates. In the old days they used to call the influenza the “old man’s friend” because it was the disease that ultimately weakened the severely ill enough to allow them to die of their diseases rather than lingering on with a debilitating ailment in an era prior to the development of effective palliative care.
As for statistics for emergency-room visits, in our modern era doctors don’t necessary see the need to actually submit samples for confirmation of flu strain when an elderly patient with a preexisting condition dies. Thus, only a small percentage of the deaths “attributed to influenza” are actually confirmed as being a caused by influenza. To be absolutely clear here when we are talking “deaths from influenza” (the stat he quotes from the Public Health Agency), we are talking only about cases where a person has died and because there was not an underlying condition a test was undertaken to confirm the diagnosis of “influenza”. In a purely technical sense a death is not recorded as an “influenza” death unless a test was administered that confirmed the actual influenza virus was the cause of the death.
As a personal example, this weekend my wife got bad news about a colleague’s son. This vibrant 30+ year-old man caught the flu and this flu left him dehydrated. When he tried to get up from his bed he fainted, and suffered a head injury in the fall that caused a cerebral bleed. He died later that day in hospital. His cause of death will not be reported as “influenza” even though that is precisely what killed him. Absent the influenza, that otherwise healthy 30+ year old would be alive today. His was an influenza-related death but would not be called “influenza” on the death certificate as his actual death was caused by a head injury related to a fall. A fall he only had because of dehydration caused by influenza.
The final point of today’s blog will be a topic Mr. Tieleman always makes a centerpiece of his anti-flu vaccine tirades: the cost of the vaccine. Like his other points, this is another case of being far too pedantic and thus missing the forest for the trees.
Consider that in the last two weeks of December 2016, the proportion of visits to BC Children’s Hospital Emergency Room (ER) attributed to influenza-related illnesses represented, 22% of all visits. That is a huge number. An even marginally effective vaccine can cut the number of hospital visits dramatically resulting in less crowded emergency rooms and bundles of saved government money. Taking a look at this resource from the CDC, it shows how incredibly effective the flu vaccine has been at reducing hospital admissions and thus reducing our national medical bill.
But we don’t only have to consider hospital stays because there are other ways in which influenza costs our economy money. According to the research for every 7 healthy children vaccinated 1 case of influenza is avoided. Now consider that number from a policy perspective. Take a class of 21 kindergarten kids. Vaccinating that class would avoid 3 cases of influenza. Now consider that a typical case of the flu usually lasts 7 to 10 days. That represents missing 5 days of school. Those 5 days of missed school are 5 days when the sick child has to be at home under the care of a care-giver; in my family’s case that means me (using sick time from work) or my wife (using her family leave from her her work as a school teacher). Each day our child is sick costs either my employer, or our provincial government (my wife’s ultimate employer) money.
Consider that an average teacher gets paid about $200 per actual school day. Missing those 5 days to take care of a sick child represents a direct cost to our government of around $1000 (to pay for the replacement teacher while my wife is at home on paid leave). Considering the flu shot costs about $20/shot those 7 shots cost the government around $140. In return they can generate a direct reduction of employment costs by about $1000. That represents $860 in reduced government costs. Don’t even get me started on the cost savings when you also include the doctor’s visits and the hospital and emergency room admissions. Can you show me any other health care intervention that saves the government over 7 times the cost of the program that Mr. Tieleman would like to cancel?
The data is clear: the flu shot reduces incidences of infection and does so at an impressive rate (around 50% effectiveness). In doing so it reduces the likelihood of serious illness for thousands upon thousands while preventing hundreds of deaths a year. Moreover, the vaccine program saves the health care system (and the public purse) a boatload of money. The 2016/2017 seasonal influenza vaccine program exists because there is a public health need for the program. It saves lives and saves money and so as long as Mr. Tieleman insists on slamming this program, I will write blog posts pointing out how wrong he is on the topic.