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R E S E A R C H A R T I C L E Open Access
Admission to hospital for pneumonia and
influenza attributable to 2009 pandemic A/H1N1
Influenza in First Nations communities in three
provinces of Canada
Michael E Green
1,2*
, Sabrina T Wong
3,4
, Josée G Lavoie
5
, Jeff Kwong
6,7,8,9
, Leonard MacWilliam
10
, Sandra Peterson
4
,
Guoyuan Liu
2
and Alan Katz
10,11
Abstract
Background: Early reports of the 2009 A/H1N1 influenza pandemic (pH1N1) indicated that a disproportionate
burden of illness fell on First Nations reserve communities. In addition, the impact of the pandemic on different
communities may have been influenced by differing provincial policies. We compared hospitalization rates for
pneumonia and influenza (P&I) attributable to pH1N1 influenza between residents of First Nations reserve
communities and the general population in three Canadian provinces.
Methods: Hospital admissions were geocoded using administrative claims data from three Canadian provincial data
centres to identify residents of First Nations communities. Hospitalizations for P&I during both waves of pH1N1
were compared to the same time periods for the four previous years to establish pH1N1-attributable rates.
Results: Residents of First Nations communities were more likely than other residents to have a pH1N1-attributable
P&I hospitalization (rate ratio [RR] 2.8-9.1). Hospitalization rates for P&I were also elevated during the baseline period
(RR 1.5-2.1) compared to the general population. There was an average increase of 45% over the baseline in P&I ad-
missions for First Nations in all 3 provinces. In contrast, admissions overall increased by approximately 10% or less in
British Columbia and Manitoba and by 33% in Ontario. Subgroup analysis showed no additional risk for remote or
isolated First Nations compared to other First Nations communities in Ontario or Manitoba, with similar rates noted
in Manitoba and a reduction in P&I admissions during the pandemic period in remote and isolated First Nations
communities in Ontario.
Conclusions: We found an increased risk for pH1N1-related hospital admissions for First Nations communities in all
3 provinces. Interprovincial differences may be partly explained by differences in age structure and socioeconomic
status. We were unable to confirm the assumption that remote communities were at higher risk for pH1N1-
associated hospitalizations. The aggressive approach to influenza control in remote and isolated First Nations com-
munities in Ontario may have played a role in limiting the impact of pH1N1 on residents of those communities.
* Correspondence: michael.green@dfm.queensu.ca
1
Departments of Family Medicine and Public Health Sciences, Queen's
University, Kingston, Ontario, Canada
2
Centre for Health Services and Policy Research and Institute for Clinical
Evaluative Sciences, Queen’s University, Kingston, Ontario, Canada
Full list of author information is available at the end of the article
© 2013 Green et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
Green et al. BMC Public Health 2013, 13:1029
http://www.biomedcentral.com/1471-2458/13/1029
Background
The 2009 A/H1N1 influenza pandemic (pH1N1) origi-
nated in Mexico and quickly spread around the world.
The first Canadian cases were reported in April of that
year. Early descriptive studies focused on risk factors for
severe disease and identified key patterns such as the in-
creased risk for children and pregnant women and youn-
ger adults as well as those with chronic conditions [1-3].
It was also assumed that Indigenous
a
communities in
several countries including the United States, Australia,
New Zealand and Canada were at increased risk: this as-
sumption was confirmed in later studies [4-8]. As a con-
sequence, public health officials in Canada began to
consider specific recommendations for Aboriginal Cana-
dians, which includes First Nations, Inuit, and Métis.
Prior studies in Canada have examined primarily
laboratory-confirmed cases [8-11] and have either exam-
ined national or provincial rates, but did not compare
these across provinces. Internationally, most prior re-
search has also focused on lab-confirmed hospitalized
cases. We are not aware of any other Canadian studies
examining the population-based impacts across prov-
inces or between Aboriginal communities and the gen-
eral population. Yet, inequities between Aboriginal and
other Canadians persist for virtually every measure of
health and social status.
The potential for health and health care disparities
among those living on a reserve compared to residents
of other communities is higher. A reserve is a small por-
tion of what might have previously been part of a na-
tion’s traditional territory, which is protected by
legislation for the use and benefit of a First Nation [12].
Although more than half (51%) of the First Nations
population in the provinces of British Columbia, Mani-
toba, and Ontario live in urban areas [13-15], there con-
tinues to be a significant portion of First Nations
individuals who live on reserves that are considered
rural and remote geographic regions. Further, it has been
documented that many First Nations people who live
off-reserve travel back to their home reserve to access
healthcare [16,17].
This study was undertaken to assess whether there
were observed differences in the rates of hospitalizations
attributable to pH1N1 in British Columbia, Manitoba,
and Ontario between residents of First Nations commu-
nities and other residents, and between First Nations in
each province.
Methods
We used administrative data to examine rates of hospi-
talizations attributed to pH1N1 for those living on First
Nations reserves and the rest of the population in British
Columbia, Manitoba, and Ontario. Results were aggre-
gated for all First Nations reserve communities in each
province. We did not merge the British Columbia, Mani-
toba, or Ontario datasets because of documented data
coding variability.
Sources of data
The data included files held at Population Health Data
British Columbia, the Manitoba Centre for Health Pol-
icy, and the Institute for Clinical Evaluative Sciences
(ICES) in Ontario. Standardized data, based on every
hospital contact, are submitted (including scrambled
personal health identifiers, diagnoses, costs, hospital-
ization, and institutionalization data) as part of a system
maintained and controlled by all provincial ministries of
health. We used the hospitalization data available
througheachprovince’s Discharge Abstract Database
(DAD) files and the demographic data available through
province-specific datasets (Consolidation file in British
Columbia, the Population Registry in Manitoba, and the
Registered Persons Database in Ontario) in order to de-
termine sex, age, and location of residence. Socioeco-
nomic quintiles were identified using standard protocols
in each province that utilize a combination of census
data and location of residence. We also utilized the la-
boratory influenza testing result files from each prov-
ince to identify the time periods of interest for waves
1 and 2 of pH1N1 in each province.
FN identification
In most provinces, current databases are unable to reli-
ably report First Nations identification. Therefore, we
created an ecological sample that was assumed to in-
clude all British Columbia, Manitoba, and Ontario First
Nations living on a reserve. Our unit of interest was resi-
dents of First Nations reserve communities. Based on
previous work by Lavoie and colleagues we used a com-
bination of 6-digit postal code and First Nations reserve
numbers (from Indians and Northern Affairs Canada) to
identify all BC, Manitoba, or Ontario residents living on
a First Nations reserve [18]. In all three provinces Regis-
tered First Nations represent over 90% of the overall on-
reserve population [16]. The remainder of the on-
reserve population will be the children of one Registered
parent and Métis or non-indigenous individuals, all of
whom depend on the same services.
Geographic mismatching can be a concern in any rural
area, where many small communities may exist within a
single postal code. In British Columbia this is of particu-
lar concern as postal codes tend to cover larger areas,
and First Nations reserves are small. In the case of First
Nations, the payer of British Columbia provincial health
premiums is the First Nation Inuit Health Branch of
Health Canada. Therefore, we were able to use both a
proxy for First Nations identification (premium payer)
and postal codes where reserves are located to track
Green et al. BMC Public Health 2013, 13:1029 Page 2 of 8
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British Columbia First Nations individuals living on
reserve.
Outcome measures
Since influenza is infrequently confirmed by laboratory
tests and the criteria for testing for pH1N1 varied over
the study period, and between provinces, we estimated
pH1N1-attributable outcomes by applying statistical
methods to administrative data. Pneumonia and influ-
enza (P&I) hospitalization (International Classification of
Diseases, Tenth Revision [ICD-10] J10-J18) in any diag-
nostic field was the primary outcome. We examined as
secondary outcomes: i) hospitalizations due to pneumo-
nia and influenza as the primary diagnosis; and ii) any re-
spiratory condition (ICD-10 J00-J99) in any diagnostic
field. To confirm the specificity of any observed differ-
ences, we examined motor vehicle collisions (ICD-10
V01-V79) as a condition where pH1N1 was not expected
to have an impact.
Data analysis
Data analyses were conducted within each province. Fre-
quent communication during the analysis stage ensured
consistency in analyses despite slight variations inherent
in the health administrative data. To estimate pH1N1-
attributable outcomes, we first defined periods of pH1N1
activity (i.e., pandemic waves 1 and 2, which were ap-
proximately April-June and October-November 2009)
using provincial laboratory data. We then determined
event rates during these periods in 2009 and compared
them to event rates during the same periods in the previ-
ous five years (2004 to 2008). The rate during the previ-
ous years served as the expected baseline for these
outcomes, controlling for inherent differences between
provinces and between First Nations communities and
the general population in terms of health services
utilization, public health prevention and control strat-
egies, and influenza disease rates. pH1N1-attributable
event rates were calculated as the difference between the
pH1N1 waves in 2009 and the baseline periods in previ-
ous years.
We conducted analyses that included crude and age
standardized rates and rate ratios. Rates of admission
were first determined for each week then aggregated to
generate average weekly rates for the time periods of
interest. For Ontario and Manitoba we also used the
First Nations and Inuit Health rurality designation to de-
termine if there were differences between Remote and
Isolated First Nations reserve communities and those
rated as Semi-Isolated and Non-Isolated. In Ontario, the
locations and categories of each community in our data-
set were compared to the information in the First Na-
tions Community Profiles on the Aboriginal Affairs and
Northern Development Canada website to ensure they
were accurate. One of the investigators (MG) has con-
tent expertise in this area and was able to resolve any
conflicts identified during this processes. In Manitoba
this information was already available and verified from
previous work by one of the investigators( JL). This was
not possible in British Columbia due to the nature of the
dataset obtained from Population Health Data British
Columbia, where aggregation beyond the community
level had already been completed prior to release of the
data set, making it impossible to use this approach. We
used a rate ratio approach as the relatively low event
counts in the First Nations communities precluded the
meaningful use of regression models to adjust for con-
founding variables. We used SAS 8.0/9.2 for data analysis
depending on the version in use at each data centre [19].
Ethics and partnerships
This project was conducted in keeping with the Tri-
Council Policy Statement on Research involving Aboriginal
Peoples [20]. As we were using provincial-level datasets,
guidance and input into the study was provided by
provincial-level First Nations organizations. Research agree-
ments were implemented between the research team and
Chiefs of Ontario, the Assembly of Manitoba Chiefs, and
the British Columbia First Nations Health Council. The
roles of the partners included review and approval of the
application for funding, the methodology used for identify-
ing First Nations communities, review of preliminary re-
sults and review, and approval of the final manuscript.
All procedures were approved by ethics boards at the
Univeristy of British Columbia, University of Manitoba, and
Queen’s University. Data access requests were approved by
Population Data British Columbia, The Health Information
Privacy Committee in Manitoba, and the Institute for Clin-
ical Evaluative Sciences.
Results
There were key demographic differences between First
Nations reserve communities and other residents in each
of the three provinces (Table 1). Residents of First Na-
tions reserves were more likely to be younger, have
lower socioeconomic status and less likely to reside in
an urban area (as would be expected given the location
of most reserves). The age and SES differences were
greatest in Manitoba and smallest in British Columbia.
Ontario had several reserve communities located in
urban census metropolitan areas, while there were none
in Manitoba. British Columbia data were not available
for this particular analysis.
Figure 1 presents the weekly hospitalization rates for P&I
in one province (Ontario) from April 2004 to April 2010.
Hospitalization rates for P&I were higher in First Nations
reserves than in other communities throughout this period.
The influence of seasonal influenza on admission rates is
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clearly evident, as is the spike in admissions due to wave 2
of pH1N1.
The remainder of the results are limited to the pandemic
periods noted in Figure 1 and the corresponding control pe-
riods (same weeks) in each of the prior five years. Table 2
presents the results for our primary outcome. The differ-
ences between age-adjusted and crude rates did not signifi-
cantly influence the results of our primary outcome so we
have presented only the crude rates. For both the baseline
period and during pH1N1 waves, the rates of admission
were highest in Manitoba. All provinces had higher rates of
admission for First Nations reserve communities during
the baseline period (RR 1.5-2.1). pH1N1-attributable ad-
missions were higher for First Nations reserve communities
(RR 2.8-9.1). In all three provinces there was a similar in-
crease (44-46%) in P&I admissions among First Nations re-
serve communities. In contrast, there was little change in
the admission rates for the general population in either
British Columbia (8%) or Manitoba (11%), but a 33% in-
crease in Ontario. The “ratio of ratios”indicates the degree
by which the proportional increase in P&I related hospitali-
zations for residents of First Nations Reserve communities
was greater than that experienced by the general population
after taking into account expected differences based on his-
torical data. This showed the increase in hospitalization
rates for residents of First Nations Reserve communities to
be 35% higher in BC, 31% higher in Manitoba and 8%
higher in Ontario.
Table 1 Sociodemographic characteristics of First Nations Reserves and Other Residents in British Columbia, Manitoba,
and Ontario, 2009.
British Columbia Manitoba Ontario
First Nations Reserves Other residents First Nations Reserves Other residents First Nations Reserves Other residents
Age <16 years 26.9% 17.2% 35.2% 19.6% 32.4% 18.4%
Age >65 years 6.1% 13.6% 5.5% 13.6% 7.06% 13.05%
% Female 48.8% 50.6% 49.1% 50.8% 50.4% 50.1%
% Urban NA NA 0.02% 65.1% 12.2% 76.8%
SES Quintiles
1 45.1% 20.1% 61.9% 16.8% 49.1% 20.8%
2 16.5% 20.1% 17.1% 19.9% 11.8% 20.1%
3 14.5% 20.2% 16.2% 20.2% 7.2% 19.6%
4 13.6% 20.0% 2.7% 21.0% 14.0% 19.8%
5 10.3% 19.6% 1.9% 21.0% 17.9% 19.7%
Urban = Census Metropolitan Area (>100,000).
SES Quintiles excluding missing results.
NA = Not available.
Figure 1 Weekly hospitalizations rates for pneumonia and influenza in Ontario. Ontario –standardized rates per 100,000 population per
week, April 2004-April 2012. Vertical bars represent waves 1 and 2 of H1N1 and corresponding control periods in earlier years.
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Our additional sensitivity analyses showed that when
P&I was used as the primary diagnosis, we found similar
results to our primary outcome (data not shown). For all
respiratory hospitalizations an increase was also noted,
but with the degree of this somewhat tempered (increases
of approximately 15% rather than 44% in Ontario for ex-
ample) as would be expected by the inclusion of other
non-infectious respiratory admissions in this outcome
(data not shown). Sensitivity analyses also showed that
there was no temporal relationship noted between motor
vehicle collision rates and pH1N1, although motor ve-
hicle collision rates for residents of First Nations reserve
communities were also noted to be twice that of the gen-
eral population (data not shown).
For Manitoba and Ontario, we were also able to com-
pare remote and isolated First Nations reserve communi-
ties to those that are not remote or isolated (Table 3). In
Manitoba the rates of admission overall and the pH1N1-
attributable rates were similar for both groups. In On-
tario, there were fewer P&I admissions in remote and
Table 2 Pneumonia and Influenza Hospitalizations (Crude Rate per 100,000 per week)
2009 2004-08 H1N1 Attributable Rate Ratio: 2009:2004-08
British Columbia
First Nations Reserves 13.77 9.48 4.29 1.45
Other Residents 6.65 6.18 0.47 1.08
Rate Ratio: 2.07 1.53 9.13 1.35*
First Nations:Other
Manitoba
First Nations Reserves 26.84 18.44 8.40 1.46
Other Residents 11.21 10.07 1.14 1.11
Rate Ratio: 2.39 1.83 7.36 1.31*
First Nations:Other
Ontario
First Nations Reserves 16.84 11.74 5.10 1.44
Other Residents 7.35 5.54 1.81 1.33
Rate Ratio: 2.29 2.12 2.81 1.08*
First Nations:Other
Crude rates of hospitalization for pneumonia or influenza (any diagnostic field) per 100,000 population per week. 2009 represents the average combined rate of
both waves of H1N1 and 2004-08 the average rate during the same weeks in each of the prior 5 years. *Indicates the “ratio of ratios”which represents the degree
to which the rate of P&I admissions increased relative to the general population after taking into account expected differences in rates based on the rates of
hospitalization for P&I in 2004-2009.
Table 3 Pneumonia and Influenza Hospitalizations by Geographic Location –First Nations Communities in Manitoba
and Ontario only (Crude rates per 100,000 per week)
2009 2004-08 H1N1 Attributable Rate Ratio: 2009:2004-08
Manitoba First Nations Communities
Remote/Isolated 27.69 18.29 9.40 1.51
Other 25.71 18.64 7.07 1.38
Rate Ratio 1.077 0.98 1.32 1.10*
RI:Other
Ontario First Nations Communities
Remote/Isolated 7.05 7.91 −0.88 0.89
Other 21.47 13.56 7.91 1.58
Rate Ratio 0.33 0.58 −0.11 0.56*
RI:Other
Crude rates of hospitalization for pneumonia or influenza (any diagnostic field) per 100,000 population per week. 2009 represents the average combined rate of
both waves of H1N1 and 2004-08 the average rate during the same weeks in each of the prior 5 years. *Indicates the “ratio of ratios”which represents the degree
to which the rate of P&I admissions in remote or isolated FN communities increased (or decreased) relative to the rates in other FN communities after taking into
account expected differences in rates based on rates of hospitalization of P&I in 2004-2009.
British Columbia data was not included as the nature of the data set did not permit this particular subgroup analysis.
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isolated communities and there was actually a decrease
in admissions between the baseline period and 2009
for these communities. In contrast, there was a 58%
increase in admissions for other First Nations reserve
communities.
Discussion
This study confirms that at a population level, there
was a greater risk of pH1N1-attributable hospitalization
(RR = 2.8-9.1) for First Nations reserve communities
than the remainder of the population. These health dispa-
rities are consistent across BC, Manitoba, and Ontario,
and consistent with other studies of hospitalized or
laboratory-confirmed cases in North America, Australia,
and New Zealand [3-11,21]. For example, Campbell et al.
found that the likelihood of hospital admissions for lab
confirmed pH1N1 in Canada was 5-7 times greater for
those with Aboriginal status compared to the general
population [10]. LaRuche et al. compared hospitalization
rates for pH1N1 across several countries and found that
the relative risk for Indigenous populuations to be be-
tween 3.0-7.7 times higher than the general population
[4]. They also noted elevated mortality (RR 3.4-5.3) [4], as
did Castrodale et al. (RR2.9-5.6) in the United States [5].
Wilson et al. also reported increased mortality for the
Maori in New Zealand (RR 2.0-7.2), and further note that
this pattern has been consistently observed in all the
major pandemics documented since 1918 [21].
We also found elevated baseline risks of P&I hospi-
talization (RR = 1.5-2.1) variability in both the baseline
and pH1N1-attributable hospitalization rates between
provinces. Some of this variability may be explained by
demographic differences between FNs reserve communi-
ties in each province. Manitoba, which had the highest
rates, also has the youngest and poorest First Nations re-
serve population. This would be in keeping with other stud-
ies, which have shown a convincing association between
lower SES and increased risk of adverse outcomes from
H1N1 influenza [22,23]. Once baseline differences are
accounted for, the relative increase in risk of hospitalization
for pH1N1 for those living on a First Nations reserve was
similar across provinces at about 45% (44-46%) compared
to prior years. In Ontario, where pH1N1-related hospitali-
zations mostly occurred during the second wave, there was
also a significant impact in the general population, while in
BC and Manitoba the impact on the general population was
minimal. This would be consistent with a prior study of
laboratory-confirmed pH1N1 hospitalizations that found
the second wave to have much higher admission rates [11].
Guidelines identified remote or isolated First Nations as
being at particularly increased potential risk and in some
provinces such as Ontario, more aggressive pandemic con-
trol strategies (such as more liberal use of antiviral medica-
tion, expanded indications for mask usage and increased
consideration of cancellation of mass gatherings) were im-
plemented [24-27]. Our data did not show increased risk
for these communities compared to other First Nations re-
serve communities at baseline, with admission rates being
essential identical in Manitoba and actually lower in On-
tario. This may be due in part to the types of facilities and
healthcare services available locally in these communities
as more isolated communities often receive higher levels of
services on site. During pH1N1 in Manitoba there was only
a slightly higher rate of pH1N1-attributable admission in
remote/isolated vs. other First Nations community types
(RR = 1.51 vs. RR = 1.38). In Ontario, there was actually a
decrease in hospitalizations in remote/isolated First Na-
tions reserve communities during pH1N1, with all of the in-
crease in admissions coming from the other community
types. This could be related to the more aggressive ap-
proach taken to control and treatment of pH1N1 in these
communities or other factors. It should be noted that as
pH1N1 was primarily a second wave event in Ontario, the
experience of other jurisdictions with the first wave of
pH1N1 was taken into consideration during the develop-
ment and implementation of clinical and public health
guidelines in that province. Future guidelines should con-
sider all First Nations communities to be at elevated risk
and also address the needs of those less isolated communi-
ties that have limited access to on reserve healthcare
services.
Limitations
A number of limitations to the study should be taken
into consideration. The first is that we are using pH1N1-
attributable rather than laboratory-confirmed hospitali-
zations as an outcome. We feel this is reasonable be-
cause not all patients would necessarily have been
tested, but this does potentially lead to incorrect attribu-
tion of cases. We did not adjust for a number of known
risk factors such chronic diseases, pregnancy, or age
group. Moreover, there are other risk factors that are not
measurable in administrative data (e.g., access to safe
drinking water or overcrowding) [28]. However, our ana-
lyses included close to the entire population in each
province and age standardization did not have a major
impact on our conclusions. The time periods for obser-
vation were based on provincial level laboratory data,
which could be confounding if the waves of H1N1 on
First Nations reserves occurred at different times from
the general population. Finally, it is likely that there was
some misattribution due to imperfect matching of First
Nation reserve boundaries with postal code boundaries.
In BC, using a combination of postal code and premium
payer to identify First Nations may result in the inclu-
sion of a small number of First Nations living outside
but close to the reserve. We believe their access to
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health services compares to that of the First Nations on-
reserve population living adjacent to them.
Conclusions
The findings reported here are unique in that analyses were
carried out across three provinces using their health admin-
istrative data to shed light on the impact of pH1N1 among
First Nations reserve communities. Findings provide empir-
ical population level evidence of both an absolute and rela-
tive increase in risk for pH1N1-attributable hospitalizations
for First Nations reserves relative to the general population.
The increased baseline risk suggests that this risk is ele-
vated in general and not specific to pH1N1.
The interprovincial variations could indicate that SES,
age, and other differences for which we do not have
regular sources of data (e.g., housing status) are import-
ant mediators of these differences. Unlike what is gener-
ally assumed, increasing remoteness of the community
was not an important risk factor. Outcomes were not re-
lated to where the communities are situated, but rather
to the care provided. Future studies should examine
more closely the influence of the types of health services
delivered locally. Still, the aggressive use of antiviral
medications in remote and isolated communities in On-
tario may have contributed to the reduced impact of the
pandemic in those areas.
Endnote
a
Throughout this paper, the term Aboriginal will be
used when statements apply to First Nations living on-
and off-reserve, Inuit, and Métis. Elsewhere, the terms
First Nations, Inuit, and Métis will be used when specific
to each of these populations. Finally, the term Indigenous
will only be used when speaking in international terms.
Competing interests
MG serves as a medical officer for First Nations and Inuit Health Branch,
Ontario Region and participated in the management of the H1N1 pandemic
on First Nations reserves in Ontario.
Author’s contributions
MG, SW, AK, JL and JK designed the study and contributed to all aspects
including the development of partnerships, acquisition of data, analysis and
interpretation of results. LM, SP and GL worked directly on the analysis of the
administrative data. All authors contributed to the discussion and review of
the manuscript. All authors read and approved the final manuscript.
Acknowledgements
This project was funded by the Canadian Institutes of Health Research
though the Applied Health Services Research on H1N1 program grant H1N-
104058. We would like to thank Marlo Whitehead, senior analyst at ICES@
Queen’s for her assistance with specific aspects of the study. Most importantly,
we would like to recognize the essential contributions of our partner organi-
zations, the BC First Nations Health Council, the Assembly of Manitoba Chiefs
and the Chiefs of Ontario, without whom this project would not have been
possible. The administrative data centres (ICES, Manitoba Centre for Health
Policy, Population Health Data BC) receive support from provincial ministries
of health. The opinions, results and conclusions presented here are those of
the authors and are independent of these funding sources. No endorsement
by these sources of support is intended or should be inferred.
Author details
1
Departments of Family Medicine and Public Health Sciences, Queen's
University, Kingston, Ontario, Canada.
2
Centre for Health Services and Policy
Research and Institute for Clinical Evaluative Sciences, Queen’s University,
Kingston, Ontario, Canada.
3
School of Nursing and Centre, University of
British Columbia, Vancouver, BC, Canada.
4
Centre for Health Services and
Policy Research, University of British Columbia, Vancouver, BC, Canada.
5
School of Health Sciences, University of Northern British Columbia, Prince
George, BC, Canada.
6
Department of Family and Community Medicine and
Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario,
Canada.
7
Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
8
University Health Network, Toronto, Ontario, Canada.
9
Public Health Ontario,
Toronto, Ontario, Canada.
10
Manitoba Centre for Health Policy, University of
Manitoba, Winnipeg, Manitoba, Canada.
11
Departments of Family Medicine
and Community Health Sciences, Manitoba Centre for Health Policy,
University of Manitoba, Winnipeg, Manitoba, Canada.
Received: 19 July 2013 Accepted: 28 October 2013
Published: 30 October 2013
References
1. CDC: Update: Novel Influenza A (H1N1) Virus Infections –Worldwide,
May 6, 2009. MMWR 2009, 58(17):435–438.
2. CDC: Update: Influenza Activity –United States, August 30 –Oct 31,
2009. MMWR 2009, 58(44):1236–1241.
3. Jain S, Kamimoto L, Bramley A, Schmitz AM, Benoit SR, et al:Hospitalized
Patients with 2008 H1N1 Influenza in the United States, April-June 2009.
NEJM 2009, 361(20):1935–1944.
4. La Ruche G, Tarantola A, Barboza P, Vaillant L, Guerguen J, Gasteullu-
Etchegorry for the epidemic intelligence team an InVS: The 2009 Pandemic
H1N1 Influenza and Indigenous Populations of the Americas and the
Pacific. Euro Surveill 2009, 14(42):19366.
5. Castordale L, McLaughlin J, Imholte S, Komatsu K, Wells E, et al:Deaths
Related to 2009 Pandemic Influenza A (H1N1) Among American Indian/
Alaska Natives –12 States, 2009. MMWR 2009, 58(48):1341–1344.
6. McCracken Trauer J, Laurie KL, McDonnell J, Kelso A, Markey PG: Differential
Effects of Pandemic (H1N1) 2009 on Remote and Indigenous Groups,
Northern Territory Australia, 2009. Emerg Infect Dis 2011, 17(9):1615–1623.
7. Dee DL, Bensysl DM, Gindler J, Truman BI, Allen BG, et al:Racial and Ethnic
Disparities in Hospitalizations and Deaths Associated with 2009
Pandemic Influenza A (H1N1) Virus Infections in the United States. Ann
Epidemiol 2011, 21:623–630.
8. Boggild AK, Yuan L, Low DE, McGeer AJ: The impact of influenza on the
Canadian First Nations. Can J Public Health 2011, 102(5):345–348.
9. Zarychanski R, Stuart TL, Kumar A, Doucette S, Elliot L, et al:Correlates of
severe disease in patients with 2009 pandemic influenza (H1N1) virus
infection. CMAJ 2010, 182(3):257–264.
10. Campbell A, Rodin R, Kropp R, Mao Y, Hong Z, et al:Risk of severe
outcomes among patients admitted to hospital with pandemic (H1N1)
influenza. CMAJ 2010, 182(4):349–355.
11. Helferty M, Vachon J, Tarasuk J, Rodin R, Spika J, Pelletier L: Incidence of
hospital admissions and severe outcomes during the first and second
waves of pandemic (H1N1) 2009. CMAJ 2010, 182(18):1981–1987.
12. Canada: Frequently Asked Questions About Aboriginal Peoples. Indian
and Northern Affairs Canada [On-line] 2010. Available: http://www.aadnc-
aandc.gc.ca/eng/1100100016202/1100100016204.
13. Statistics Canada: British Columbia: Aboriginal Identity (3), Registered
Indian Status (3), Age Groups (12), Sex (3) and Area of Residence (6) for
the Population of Canada, Provinces and Territories, 2006 Census - 20%
Sample Data. Statistics Canada [On-line] 2006a. Available: http://www12.
statcan.ca/english/census06/data/topics/RetrieveProductTable.cfm?
ALEVEL=3&APATH=3&CATNO=97-558-XCB2006010&DETAIL=0&DIM=&
DS=99&FL=0&FREE=0&GAL=0&GC=99&GK=NA&GRP=1&IPS=97-558-
XCB2006010&METH=0&ORDER=1&PID=89126&PTYPE=88971&RL=0&S=1&
ShowAll=No&StartRow=1&SUB=734&Temporal=2006&Theme=73&VID=0&
VNAMEE=&VNAMEF=&GID=614145.
14. Statistics Canada: Manitoba: Aboriginal Identity (3), Registered Indian
Status (3), Age Groups (12), Sex (3) and Area of Residence (6) for the
Population of Canada, Provinces and Territories, 2006 Census - 20%
Sample Data. Statistics Canada [On-line] 2006b. Available: http://www12.
statcan.ca/english/census06/data/topics/RetrieveProductTable.cfm?
Green et al. BMC Public Health 2013, 13:1029 Page 7 of 8
http://www.biomedcentral.com/1471-2458/13/1029
ALEVEL=3&APATH=3&CATNO=97-558-XCB2006010&DETAIL=0&
DIM=&DS=99&FL=0&FREE=0&GAL=0&GC=99&GK=NA&GRP=1&IPS=97-558-
XCB2006010&METH=0&ORDER=1&PID=89126&PTYPE=88971&RL=0&S=1&
ShowAll=No&StartRow=1&SUB=734&Temporal=2006&Theme=73&
VID=0&VNAMEE=&VNAMEF=&GID=614142.
15. Statistics Canada: Ontario: Aboriginal Identity (3), Registered Indian Status (3),
Age Groups (12), Sex (3) and Area of Residence (6) for the Population of
Canada, Provinces and Territories, 2006 Census - 20% Sample Data. Statistics
Canada [On-line]. ; 2006c. Available: http://www12.statcan.ca/english/
census06/data/topics/RetrieveProductTable.cfm?ALEVEL=3&APATH=3&
CATNO=97-558-XCB2006010&DETAIL=0&DIM=&DS=99&FL=0&FREE=0&
GAL=0&GC=99&GK=NA&GRP=1&IPS=97-558-XCB2006010&METH=0&
ORDER=1&PID=89126&PTYPE=88971&RL=0&S=1&ShowAll=No&
StartRow=1&SUB=734&Temporal=2006&Theme=73&VID=0&VNAMEE=&
VNAMEF=&GID=614141.
16. Lavoie JG, O’Neil J, Sanderson L, Elias B, Mignone J, Bartlett J, et al:The
Evaluation of the First Nations and Inuit Health Transfer Policy. Winnipeg:
Manitoba: First Nations Centre for Aboriginal Health Research; 2005.
17. Institute of Urban Studies, U. o. W., Assembly of Manitoba Chiefs, &
Manitoba Métis Federation: First Nations/Métis/Inuit Mobility Study, final
report. Winnipeg: University of Winnipeg; 2004.
18. Lavoie JG, Forget E, Prakash T, Dahl M, Martens P, O’Neil JD: Have
investments in on-reserve health services and initiatives promoting
community control improved First Nations’health in Manitoba? Soc Sci
Med 2010, 71:717–724.
19. SAS Corporation: Carey North Carolina USA.
20. CIHR Aboriginal Health Ethics Working Group: CIHR Guidelines for Health
Research Involving Aboriginal People. CIHR; 2011. Accessed online at
http://www.cihr-irsc.gc.ca/e/29134.html.
21. Wilson N, Barnard LT, Summers JA, Shanks GD, Baker MG: Differential
Mortality Rates by Ethnicity in 3 Influenza Pandemics Over a Century.
New Zealand. Emerg Infect Dis. 2012, 18(1):71–77.
22. Tricco AC, Lillie E, Soobiah C, Perrier L, Straus SE: Impact of H1N1 on
Socially Disadvantaged Populations: Systematic Review. Plos ONE 2012,
7(6):e39437. 10.1371/journal.pone.0039437.
23. Lowcock EC, Rosella LC, Foisy J, McGeer A, Crowcroft N: The Social
Determinants of Health and Pandemic H1N1 2009 Influenza Severity.
Am J Public Health 2012, 102:e51–e58.
24. Public Health Agency of Canada: Guidance for Remote and Isolated
Communities in the Context of Pandemic H1N1 Outbreak. Ottawa, Ontario:
Government of Canada; 2009.
25. Government of British Columbia: Small and Isolated Communities British
Columbia’s H1N1 Pandemic Influenza Response Plan. Influenza pandemic
Planning for Small and Isolated Communities. Victoria, BC: Government of
British Columbia; 2009.
26. Manitoba Health, Public Health Division: Guidelines for H1N1 Influenza
(Updates May 1, May 9, June 19, 2009). Winnipeg, Manitoba: Government of
Manitoba.
27. Ontario Ministry of Health and Long Term Care: First Nations Guidance for
H1N1.; 2009.
28. Pollock SL, Sagan M, Oakley L, Fonatine J, Poffenroth L: Investigation of a
pandemic H1N1 influenza outbreak in a remote First Nations community
in northern Manitoba, 2009. Can J Public Health 2012, 103(2):90–93.
doi:10.1186/1471-2458-13-1029
Cite this article as: Green et al.:Admission to hospital for pneumonia
and influenza attributable to 2009 pandemic A/H1N1 Influenza in First
Nations communities in three provinces of Canada. BMC Public Health
2013 13:1029. Submit your next manuscript to BioMed Central
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