Skip to content

More H1N1 flu controversy: vitamin D deficiency, being elderly, and the seasonal vaccine

September 29, 2009

Here are a few questions that have been asked of me in response to my first H1N1 post, or at work in the process dealing with other healthcare providers who are concerned about their well-being during the flu this season. I’m not an expert in H1N1, and below are simply my opinions on the issues raised. I think discussion is important and you can take what you will from it.

1. Is Vitamin D deficiency linked with H1N1?

According to the website of naturopath Dr. Mercola, being deficient in Vitamin D makes one susceptible to H1N1. He argues this by employing CDC data about recent deaths in chronically ill children. [ JI: I hope you will bear with me as I think this is an important idea, and it’s worth re-hashing our discourse in this public forum]

The argument is as follows:

1. kids who are sick are more susceptible to getting sick! (i.e. kids with cerebral palsy are more likely to get very sick with H1N1)
2. kids who are chronically sick are vitamin D deficient
3. those who get H1N1 must be vitamin D deficient

Yes, the correlation may be there, but premise 3 does not follow from the axioms 1 &2.

As the article says, lots and lots and lots of children are Vitamin D deficient, and they don’t all have H1N1. Also, of those who have H1N1, not all are Vitamin D deficient [ok, this article does not demonstrate that ANY of the children who died were in fact Vitamin D deficient, it just says it is likely]. In addition, no mechanism for Vitamin D and susceptibility for flu is proposed.

Compound this with the fact that the website sells Vitamin D  (hello, conflict of interest!) and I just don’t buy it. This is where I feel the Internet can be a dangerous place. I am lucky enough to have been through the rigours of undergrad science and medical school, having had critical thinking beaten into me.  I think lots of non-allopathic practitioners and health reporters (including those with the CBC) are lacking in this area. Education in language and logic, as well as scientific reasoning, should be necessary for anyone trying to draw scientific conclusions or to interpret technical literature.

That said, in my part of the world, people don’t get enough Vitamin D from the sun between October and April. Talk to your doctor and see if you need Vitamin D for bone health.

2. Are older  people already exposed to H1N1, and thus resistant?

Yes and no. People born before 1950 may have encountered, carried, or been actively infected with a similar strain of the flu, according to a CDC report in May 2009 (MD Consult news). Past exposure means a potential for current resistance. But not everyone over a certain age will have been exposed, and even if they were, it is not certain that they will have maintained any degree of resistance. On an individual level, this fact should not affect whether a person get a flu vaccine. I think it’s best to consider this piece of news as an interesting explanation for the lower-than-expected rate of H1N1 in the senior population.

3.  Does the seasonal flu vaccine interfere with the H1N1 vaccine’s efficacy?

Maybe? So far, there isn’t a lot of data on this. Preliminary testing reveals there may be some interaction. Quebec has taken a hardline stance on this, intending to offer only the H1N1 shot, but I think the safest thing is to wait for more information. Lots of medications are known to interact, and in many cases, staggering the dosing (i.e. leaving enough time between each medication) can be helpful for avoiding/reducing the degree of interaction. Seasonal flu shots are due in October, and H1N1 vaccines won’t be available until November. Seasonal flu is not a nice beast either. Just because then H1N1 strain is getting all the media attention, it doesn’t mean the seasonal flu is going to forget to infect us.

4. Are vaccines safe? Aren’t they full of Mercury and other toxins? Don’t they cause autism?

I hear these questions a lot. I’m going to address it more thoroughly in a separate post, because I think it deserves a lengthy discussion. Stay tuned!

8 Comments leave one →
  1. September 29, 2009 9:25 am

    Another great post Doc

  2. September 29, 2009 10:08 am

    I have seen hundreds of H1N1 Flu and thus far I don’t think I’ve seen a single person over the age of 35 with this even though it is rampant in the community. Unfortunately I am under 35 and washing my hands till the skin cracks.

    Of course, this is the experience of one physician. I imagine the CDC has much better data.

    • September 29, 2009 4:32 pm

      I saw one 41 year old, very very sick Vent+ CRRT, was previously healthy.

      We see a lot in the clinics, but typically yes, they are younger people. Often we don’t bother to swab/type them if they are clinically well enough to rest at home, since it wouldn’t change management.

  3. Laena permalink
    September 29, 2009 3:42 pm

    Jessica, It’s not directly related, but I was thinking you might be interested anyway–
    Last week we had our CanPREP (the pandemic flu ethics thing i work on) symposium at the JCB–to summarize tentative findings and get feedback from respondent panels. One interesting bit of info from the stakeholder focus groups (and echoed in other studies)is that a surprising number of HCWs are not planning to report for work in a pandemic, esp if they fear their health would be at risk. Jeff Blackmer, the CMA ethics director, was one of the respondents and he had some interesting stuff to say about it.

    I don’t know where exactly his comments are….likely near the end of this section.

    • September 29, 2009 4:18 pm

      thanks! looks like the panel talks during the “green” part of the timeline. The attitudes toward global aid are pretty interesting!

      I’ve already been around H1N1 (confirmed, severe case, maybe fatal) but I can’t be afraid. The flu CAN be a deadly thing, but for health workers, we are so conscious of infection that it seems we might be less at risk of contracting it. I mean, we are used to washing our hands, donning masks/gowns/gloves when people are coughing, and we have privileged access to safety equipment (and possibly vaccination). If it were airborne spread, yeah, I would not want to go to work, but it’s only droplet and we know how to to prevent its spread.

  4. October 2, 2009 8:18 pm

    Here’s an article with compelling evidence re the link between D and susceptibility to flu:

  5. Dr. A permalink
    October 10, 2009 5:18 pm

    Dear Colleagues,

    For succinct and easy-to-read commentary on the current state of knowledge about vitamin D and influenza, have a quick read through the influenza-related postings on . For more details, a list of published articles on vitamin D and influenza is posted at

    I was particularly interested in Dr. Cannell’s recent posting about reports sent to him by two physicians regarding extremely low pandemic influenza incidence in a long term care facility and a family practice where residents / patients are taking supplemental vitamin D – posted at

    BTW, I’m sure influenza spreads by droplets, but the infective dose for virus inhaled into deep lung (i.e., droplet nuclei, aerosols) is far lower than for virus reaching only the nose/upper airways (i.e., droplets) . Therefore, we shouldn’t be so sure that influenza – especially pandemic influenza – doesn’t spread by aerosol. You might want to have a quick read of the discussion in this recently published study of influenza virus aerosol in ER’s: (full text free) My take on this is that if respiratory droplets don’t get into the air in the first place, they can’t turn into droplet nuclei – which is why coughing/sneezing patients should wear surgical masks to catch infectious droplets from coughing, sneezing, talking, etc. before they can get into the air and turn into droplet nuclei. Next best – catch cough/sneezes in the upper sleeve, as fabric traps and inactivates virus.

    For a systematic review of RCT’s on vitamin D supplementation vs assorted infections, including influenza, try Endocr Pract. 2009 Jul-Aug;15(5):438-49. Abstract is posted at

    For an example of a paper reviewing the mechanisms by which vitamin D supports immunity, try Adams et al, Vitamin D in Defense of the Human Immune Response, in the 2007 Annals of the New York Academy of Sciences – abstract posted at

    Me, I’m taking 5,000 IU of vitamin D a day. Based on the available information I’ve been able to find, there’s a good chance it will enhance my immune response to pan flu – and I’ve been taking it long enough I should be in the target mid-physiological range of 125-175 nmol/L 25(OH)D. If you haven’t been taking 5,000-10,000 IU/day before, be sure to read Dr. Cannell’s caveats about the risk of unmodulated cytokine response just below and at the lower level of the the physiological range – as well as his advice about taking a good solid loading doses of vitamin D if you do come down with symptoms of pandemic influenza. –


  1. More H1N1 flu controversy: vitamin D deficiency, being elderly, and the seasonal vaccine | H1N1DEATHS.US

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: