RSV and The Ulu: The Cutting Edge of Research into the Causes of Severe Recurrent Lower Respiratory Tract Infections in Inuit Infants

RSV and The Ulu:The Cutting Edge of Research into the Causes of Severe Recurrent Lower Respiratory Tract Infections in Inuit Infants Tom Kovesi MD Pediatric Respirologist Associate Professor of Pediatrics Children’s Hospital of Eastern Ontario University of Ottawa Ottawa, Canada

BronchiolitisBronchiolitis isan infection, causedby a virus, of thevery tiny airwaysin a baby’s lungs

Northern Communities Have the Highest Incidence of Severe RSV Bronchiolitis in the World Hospitalization Rate per 1000 infants500 All United States400300 Yukon-Kuskowkwim Delta (Alaska)200100 Baffin Region, Nunavut 0 Karron, J Infect Dis 1999; Banerji, CMAJ 2001

Nunavut has the highest rate ofTuberculosis infection in Canada 160 140 120 Canada (general) 100 80 Canadian Aboriginals 60 Inuit 40 20 0 TB rates per 100,000 persons

What the Houses? Indoor Air? Do they play a role?

What About Ventilation? Cape Dorset Pilot Project: Kovesi, Indoor Air 2006 Multi-Community Study: Kovesi, CMAJ 2007

Occupancy Distribution Median number occupants: 6, mean 5.9, range 2-12Number of Houses 12 10 8 6 4Cape Dorset,20 houses ofInuit Infants 2(Kovesi, 0Indoor Air 2.0 4.0 6.0 8.0 10.0 12.02006) Number of People Per House

Environmental Tobacco Smoke Exposure 5% 5% 90% Smoking Reported Likely Smoking No SmokersSmokers present 90% (probably 95%) of households

VentilationVentilation within recommended Mean CO2 > 1000 ppmCanadian standards (7.5 L/s/person) Recommended < 1000 79.9% 66.7% > 1000 20.1% 33.3% Below Recommended• 96 Inuit children in 4 communities:• Mean ventilation 5.6 L/s/person• Mean CO2 1358 ppm (Kovesi, CMAJ 2007)

Risk of Lower Respiratory Tract Infection 3000 12 10 2000 8 Mean CO2 (ppm) Occupancy 6 1000 4 0 2 N= 21 13 N= 25 15 Absent Present Absent Present Pneumonia Pneumonia• Ventilation also known to be important risk factor for TB (Menzies, Ann Int Med 2000)• *too few non-smoking households to test the effect of smoking

Heat Recovery Ventilators• Heat Recovery Ventilators bring fresh outside air into furnace, transfer heat from stale air to fresh air to maintain energy efficiency, and move stale air out of house• Trial of HRV’s installed in homes of Inuit children 5 years & less in 4 communities• HRV’s were installed in fall-winter 2006-2007: – Clyde River – Igloolik – Pangnirtung – Pond Inlet

Study HRV’s• Venmar Constructo 1.0 HRV, – (Venmar Ventilation Inc.)• Determined that additional 25-30 L/second ventilation needed to provide 7.5 L/s/person• Active HRV’s provided this ventilation• Placebo units circulated air in the house, but not increase the house’s outside (fresh) air• Placebo units were reprogrammed as functional devices at end of study (reprogram internal circuit board)

Conducting Research in Nunavut– Community Support • Town Hall Meetings: Pilot & Multi-community Studies; mainly assumed for HRV study • Qikiqtani Inuit Association, Nunavut Tunngavik Inc. • Approval from Nunavut Research Institute, Ministry of Health and Social Services– Need for community research coordinators with good organizational and computer skills (“too few and in too much demand”– Capacity-building: enlisted high school students to help with collecting data

Heat Recovery Ventilator Venmar HRV, Pond Inlet, Nunavut

HRV Study Findings - Engineering• Installations – 68 HRV’s installed – 51 available for analysis • Units (6) in Clyde River couldn’t be powered • 3 families dismantled units • Children in 4 families moved• HRV’s significantly reduced indoor CO2 (33%) – Mean CO2 1385 ppb placebo units – Mean CO2 924 ppb active units

Effect of HRV’s on Reported Wheezing • Significant reduction in risk of reported rhinitis (not associated with cold air exposure) (p = 0.0044)

Challenges• HRV’s significantly reduced relative humidity (25.6 vs 30.9%) & tended to reduce indoor temperature• Occupant complaints (house colder, drier…) • 21% active houses, • 27% placebo houses• Units unplugged > 50% of study period in ~20% houses (counter data, questionnaires)

Research Questions• Are Heat Recovery Ventilators the answer? – Maintenance and installation issues – Dry air – Small but real electricity cost – Retrofits• Can Heat Recovery Ventilators be engineered better for very cold weather performance? – Issue of drafts• Role of overcrowding/need for new homes versus ventilation (e.g. heat recovery ventilators)• Role of surface v.s. airborne transmission virus

Future Research (2)• How to deal with environmental tobacco smoke• Human architecture of Inuit housing• Capacity-building – research in Nunavut

Acknowledgements• Program of Energy Research and Development, NRCan• Nassivik Centre, CIHR• Canada Mortgage and Housing Corporation• Natural Resources Canada• Qikiqtani Inuit Association• Venmar Ventilation Inc.• Nunavut Housing Corporation• Health Canada• Children’s Hospital of Eastern Ontario Research Institute• Department of Health and Social Services, Government of Nunavut

RSV and The Ulu: The Cutting Edge of Research into the Causes of Severe Recurrent Lower Respiratory Tract Infections in Inuit Infants

by National Aboriginal Health Organization on Mar 22, 2012

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RSV and The Ulu: The Cutting Edge of Research into the Causes of Severe Recurrent Lower Respiratory Tract Infections in Inuit Infants Presentation Transcript