Welcome to DrPHealth

Please leave comments and stimulate dialogue. For those wanting a bit more privacy or information, email drphealth@gmail.com. Comments will be posted unless they promote specific products or services, or contain inappropriate material or wording. Twitter @drphealth.

Thursday 27 February 2014

Vaccine safety, can we make our monitoring system better?

Public Health Ontario has released its first report on vaccine safety PHO AEFI 2012 report .  Great news for those objectively trying to ensure we utilize quality and safe vaccines.  It is not a first, Health Canada used to release  such reports decades ago and then stopped in the pre-PHAC days.  There are vestiges of a vaccine safety system in Canada, actually a very good one, but lacking in national or even provincial reporting, until now.

Canada has a solid adverse events following immunization (AEFI) reporting system CAEFIS .  Standardized reporting forms, electronic data collection and transmission, formalized causality assessment processes -  all of which seems headed into a black hole.  The data are available for those who want to mine the data sets and know who to ask.  The problem is a lack of dedicated resource focused on vaccine safety surveillance.  Hence we collect the data and it sits.  Occasionally at an immunization conference one may find a poster on a provincial sub-analysis of the data, but rarely has anyone been so bold as to put the data out in the public eye.

So congratulations to PHO despite the shortcomings in the data.  We know that AEFI reporting by physician delivered systems is substantively less frequent and qualitatively different than where public health nurses diligently collect and submit the data.  Physicians are less likely to report, and much less likely to report what public health calls ‘mild’ AEFIs even though they are very disconcerting to parents.

Underestimation of actual rates because of relatively poor data quality is likely the main reason most jurisdictions are uncomfortable in data release (it is not that the findings suggest that there are significant harms of vaccines that there is a reluctance).  To this end, releasing the Ontario data does everyone a service.  It demonstrates the safety of vaccines, it demonstrates that public health does seriously care about AEFIs, and it demonstrates to the immunizing community that all those forms and time spent collecting AEFI information is being put to use.  Where generators of the data see the data being put to use, data quality and quantity will improve. Can the other provinces follow suit?  Or perhaps agree to let PHAC release the Canadian data. 

Canada has for over 17 years poured money into the major pediatric hospitals to have nurses intensively investigate cases admitted with events after immunization.  Probably the most biased method of data collection, and given the sparse funding for the universal data collection system,  clearly something that needs questioning.  The IMPACT program does produce a plethora of scientific publications carefully listed at the IMPACT   website.   The impact of IMPACT deserves greater scrutiny but appears to have become a sacred institution in Canada and a diversion of the scarce vaccine safety resources nationally.

Why in Canada have we perpetuated an elitist and biased surveillance system while allowing a standardized national system crumble should raise questions.  Worse, the IMPACT system skews what we can say about vaccines as it biases towards supporting vaccines as safe rather than stating vaccine safety in an objective and clear manner so that consumers can make an informed choice.  PHO’s report also contains biases towards communicating vaccines as safe.  

And then we wonder why parents remain skeptical about public health claims of the safety of vaccines.  Until we objectively and consistently report on the actual risks, that skepticism will continue to grow, fueled by what amounts to bad science.

Internationally those interested in vaccine safety should follow the   Brighton Collaboration as a body that is applying scientific rigor to the questions of vaccine safety.  The US approach of allowing anyone to submit a report on adverse events following a vaccine likely biases to overreporting of the effects of vaccines, but does present the worst case scenario VAERS  and is transparent.    


A closing note, the routinely available vaccines remain the best and safest way to protect ourselves and our families. It is almost unconscionable and unethical to withhold immunization from our children and ourselves.   While we should be critical of the current AEFI reporting system and accountability which has room to improve, there is nothing hiding in the data or reports that would do anything but provide further assurance about the safety of the vaccines we use.  In this respect, PHO should again be congratulated for challenging the Canadian public health system to be transparent and accountable on one of its foundational pillars.  

Friday 21 February 2014

Disparities in Cancer Control – or the determinants of cancer survival

Hot off the press is a well written exploration of disparities in outcome related to cancer management in Canada.  Produced by the Canadian Partnership Against Cancer who have effectively advocated and received funding to improve cancer outcomes nationally, and includes most of the provincial cancer control agencies augmented by the Canadian Cancer Society (although the actual partners are not listed on their Website home) .  The maintain a wealth of excellent information and surfing their site is worth a few minutes.

Perhaps it is notable that the disparities report is not yet locatable on the Partnership website, but can be accessed at Disparities in Cancer Control.   The 75 page report delves into the inequities carried by lower income, rural and remote residents, new immigrants, and carefully skirts First nations issues. 

The reading is not for the average Canadian, with a degree in epidemiology an asset.  However most public health professionals will be able to appreciate the tabulations against the three identified groups by; cancer risk factors, access to cancer screening, from screening to resolution for breast cancer, incidence and mortality from stage comparable cancers,  time of treatment, type of treatment (eg mastectomy versus breast conserving surgery), clinical trial participation, and finally a specific section on survival. 

While the majority of findings are not surprising in that those in lower income groups, those living in rural and remote areas, and those geographic areas with higher proportions of immigrants tend to be associated with measures that are relatively poorer, there are some surprises.  Notably are some of the relationships between risk factors which in this study puts smoking and alcohol consumption, and obesity rates higher in higher income groups, and generally lower in immigrant populations. 


While not yet a full exploration of the impacts of determinants of health on cancer, it is a step in the right direction, and well worth keeping a copy for reference.  

Tuesday 18 February 2014

Chikungunya disease – an emerging threat from the West Indies

Perhaps if you want to avoid attention, name a disease in such a fashion as to be unpronounceable.  The illness comes from a Makonbe word meaning “that which bends up” in reference to the impact the disease has on joints.   The illness has been widely found in Africa and Southeast Asia, has only recently been reported from the West Indies islands of the Caribbean since Dec 2013.   IN a short space of time, some 500 cases have been reported

The typical illness begins 3-4 days after a bite from an Aedes aegypti or A. albopictus infected mosquito.  Notable in presentation for fever, its hallmark is arthritis/arthralgia that can be debilitating in the short term and can result in rheumatologic symptoms for months to years – hence the unwieldy name.  While debilitating, mortality is uncommon and supposedly limited to older persons, currently with only one recorded death in the West Indies outbreak. Albeit that most work is done in developing countries where immunologically compromised persons may not be identified as a risk population.

The most notable issue with this outbreak is the geographic jump to the Americas, and the potential for yet another introduction of an organism previously not known to be endemic.  Comparative examples include Lyme disease and West Nile Virus Fever, where introductions into relatively naïve populations are associated with manifestations not noted in the countries from which they arose.  

In this respect, watching the dispersion of this virus through the Americas should be of public health interest.   Expansion in just a couple of months has been notable, and cases of exportation among travelers have been documented.  As the virus crosses into more populous tourist areas, further exportation may be expected.  


PAHO is maintain good information, and an excellent  information sheet for health care workers,  as well as regular updates on disease spread.  The geographic distribution as of mid-February is posted below.   The question, when will we see the first cases crossing into US or Canada among tourists?   


Monday 17 February 2014

Hookah use: A Science Update on a widely read subject

A DrPHealth posting from April 20 2012  on hookah hazards has recently come under significant activity. Now the second most visited posting and likely to move into the most viewed within a month.   The question of course being why?   Seems a moderate about of internationally directed traffic to the site.

For those following the issue, some recent publications are worth reviewing on health effects of hookah smoking.  CDC December 2013 with a key emphasis that while smoking sessions are less frequent, that their length results in inhalation levels comparable to more than a pack of cigarettes, and the actual amount of smoke inhaled may closer to a hundred or more cigarettes. However much of the CDC statement is based on equivalency risk for hookah smoking compared to cigarettes and not separately derived.  CDC delved deeper in policy options their Preventing Chronic disease 2012 publication again not based on specifically directed science. 

The science remains sketchy, though not reassuring.   A 2012 article in AJPH measured PM2.5 levels in hookah lounges with average readings for just being in the lounge.  For nine of ten lounges the ranges were 67 to 220 ug/m3, all unhealthy and comparable to significant fire smoke event situations.  One lounge averaged over 700, suggesting that even among hookah lounges there are characteristics that could mitigate or exacerbate potential health impacts. 

One case control study from Pakistan suggested lung cancer risk was six times greater than non-smokers, while smokers had a four times increase over non-smokers.  An early Pakistan study on increases in Carcinogenic Embryonic Antigen (CEA) has received considerable critique for biases. 

There is a minor research line on hypoxia impacts, carbon monoxide levels and related evidence of polycythemia among users.  There is considerable research focuses on behavioural sciences such as population use and decision processes, some looks at ecological relationships such as esophageal cancers over geographic regions. 

Conversely the number of papers on synthesis of knowledge, on policy implementation and on the purported health hazards of hookah appear to exceed primary research on the topic.


Hence, while policy has moved appropriately forward and science remains suggestive that the risks of hookah use are comparable or worse than cigarette smoking, our knowledge base on measured risks remains sketchy.   Certainly there is little published anywhere suggestive that hookah is a safer alternative than smoking.  

Hookah use is often precluded through appropriate smoking control regulation and the existing evidence continues to support its preclusion.  

Friday 14 February 2014

Valentine's Day - a celebration of the public health benefits of couples

Founded in liturgical celebrations with a variety of lore associated with its origins, Valentine’s Day was a feast day in honour of St. Valentine, and became prominent as a spring rite in celebration of courtship and love.  While detractors may be put off by commercialization, it is a day to reflect on the role of social relationships in support of health

Long been a favourite variable in epidemiological studies, in the mid 1850’s William Farr first demonstrated that marriage bestowed longer life than celibacy, and that the loss of lifetime partner subsequently reduced life expectancy of the remaining widow/widower.

The list of proposed benefits range from reduced cancer and dementia rates, lower surgical interventions, less hospitalization.  Uncoupled persons were substantively higher at risk for violent outcomes including homicide, suicide, even motor vehicle crashes. The one down side to marriage appears to be an increase in obesity. 

Subtler nuanced work demonstrates that happiness within the couple further extends benefit, and discord can actually result in worse health outcomes than being single.  Biochemical and immunological changes associated with increased or reduced stress may explain a portion of the variance.

As the institution of marriage has morphed through cohabitation arrangements, extended life expectancy and acceptance of same-sex coupling, the traditional family has changed.  While two thirds of Canada’s families remain in traditional marriages, substantial increases in common-law arrangements were noted between the last two censi.  Same sex marriages increased by over 40% between 2006 and 2011.  12% of family units involving children were blended families. More on marriage in the census can be found at Stats Can 2011 census on families

Divorce rates have decreased slightly recently but have been relative constant since reform of the Divorce Act in the late 1980s.  Still an estimated 40& of first marriages will end with divorce in Canada, Failure rates of subsequent marriages increase.  Putting those who have divorced at higher health risk than still married.  Ages of divorce have steadily been increasing over the past two decades.   More on demographics of failed marriage can be found at Employnent and Social development Canada


 Lifetime coupling remains a significant health benefit, and on Valentine’s Day, a time to renew investment in that commitment for those who have entered into a marriage arrangements.  For those still exploring, Valentine’s Day starts a nearly two century old traditional of spring time romancing.