Patterns of Temperature and Avian

Influenza Outbreaks

Carol MatasciPacific Disaster Center

Supervisor: Pam Cowher

Avian Influenza

Global Outbreak

2 – 7.4 million deaths

231 total human cases

133 deaths confirmed by WHO

(World Health Organization) As of July 20, 2006

Avian Influenza and Temperature

Temp°C

Temp°F

Virus Survival

4 °C 39.2 °F 35 days

37 °C 98.6 °F 6 days

What is the relationship between temperature and the location of outbreaks?

Intent

PredictPrevent

AndPrepare

Minimize HarmfulImpact

Analyze

Geographical Information

Systems(GIS)

Store and manipulate data

in layers

Avian Influenza Case Data

• Avian Influenza Case Data Source:

•This analysis: avian cases only

World Organisation for Animal Health

World Climate Data

Climate Data Source:

The Global Historical

Climatology Network (GHCN)

Microsoft Access

ArcGIS

World Climate Data

Problem: some areas had little data

Indonesia

2005 Stations

Temperature Stations around

the world

World Temperature Interpolation

Example: January 2006Inverse Distance

Weighting (IDW) Interpolation

Elevation Adjustmen

t Model

Average Month Temperature

Map

Pairing Temperature and Case Data

• Avian Case & Temperature

• Number of cases / temperature

January 2006

Month PriorTemperature

Month AfterTemperature

Month OfTemperature

AvianCase &

Statistical Analysis

Pearson Correlation

What is the relationship between temperature and the number of outbreaks?

- Assumes linear distribution

- Does a correlation exist?

0.143 correlation

No significant correlation

Statistical AnalysisFurther graphical examination in Microsoft Excel

No satisfactory trendline

Bimodal Distribution

0

50

100

150

200

250

300

-24

-21

-18

-16

-14

-12

-10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Temperature (C)

Fre

qu

en

cy

(#

ou

tbre

ak

s)

Further Analysis

Analysis of bimodal distribution:

Countries with cases at 2°C

Suggests that temperature may influence outbreaks through migration patterns

0

50

100

150

200

250

300

-24

-18

-14

-10 -6 -2 2 6 10 14 18 22 26 30

Temperature (C)

Fre

qu

ency

of

ou

tbre

aks

DOM

MIG

Temperature and Case Animation

Further Research Suggested

• PROCESS can be used again• Data:

– More detailed temperature data– More detailed case data– Larger spread of cases– More time

• Domestic vs. Migratory Case Patterns

temperature migration

outbreaks

Conclusion

“A kolea, or plover, was a bad omen for ancient Hawaiians. A bird circling a home while uttering an eerie cry was a sign of death. “

+

temperature

other factors

Protect Hawai’iand the rest of the world

Avian Influenza

Model

Mahalo!Pam CowherBryan BoruffMaria NievesSharon Mielbrecht

Malika BellLisa HunterHilary O’BryanShort Course Team

Leslie WilkinsIsla Yap

Mark Hoffman

Kahu Charles Kauluwehi Maxwell

Funding provided through the Center for Adaptive Optics, a National Science Foundation Science and Technology Center (STC), AST-987683.

Resources

• http://www.noaa.gov/• http://www.who.int/topics/avian_influenza/en/• http://www.oie.int/eng/en_index.htm • http://en.wikipedia.org/wiki/Adiabatic_lapse_rat

e• www.hawaii.edu• http://starbulletin.com/2003/03/09/features/sto

ry1.html

• Elevation data: Shuttle Radar Topology Mission (SRTM)

• Data Source: Pacific Disaster Center

Questions?