CLIMATE CHANGE AND PANDEMIC INFLUENZA:

THRESHOLDS AND ADAPTATION

Kirsty Duncan PhD FSAScotHealth Studies, University of Toronto at

Scarborough ©

H5N1 IN HUMANS:SYMPTOMS

• fever

• abdominal pain, bleeding from the gums and nose, chest pain, diarrhoea, vomiting

• pneumonia

• multi-organ dysfunction

H5N1 IN HUMANS:TREATMENT

• some anti-viral drugs (e.g. Tamiflu)

-improve chance of survival

• older antivirals

• antibiotics

• the disease currently kills over 60% of its victims [357 cases, 225 deaths (31/01/08)]

H5N1: THE CONCERN

• is affecting new animal hosts• is increasing its geographic range• is highly pathogenic• is mutating rapidly• several instances of limited human-to-human

transmission have occurred• causes severe disease in humans• has many genetic similarities to the 1918 virus

PANDEMICS

• global epidemic due to a newly-emerged strain of flu

• few, if any, people have any immunity

• three pandemics in the last century– 1918 (H1N1)– 1957 (H2N2)– 1968 (H3N2)

EPIDEMIOLOGY

• the principal vectors are:– the migration of wild birds harboring the virus

• Bar-headed geese

• Brown-headed gulls

• Great black-headed gulls, etc.

– trade in domestic poultry• crew

• egg flats

• trucks

WEATHER AND MIGRATION

• weather can directly and indirectly affect breeding success and migration– chilling or starving young– foraging conditions– temperature affects pre-migratory preparation– fronts signal when to migrate– high pressures signal when to feed– wind conditions affect flying

CLIMATE CHANGE AND MIGRATION

• global temperature is expected to increase 1.1-6.4 C over the coming century– this warming is likely to be without precedent

during the last 10,000 years

• if springs become warmer, birds will nest earlier– in North America, Tree Swallows breed 9 days

earlier than 30 y.a.

SUMMER AND FALL 2006

• sixth-warmest year on record since 1850• Europe experienced its warmest fall in 500 years

– Central England experienced warmest, July, September, and autumn temperatures

– Switzerland experienced November and early- December temperatures 10C above normal

– anecdotally, in North America: New York City experienced no snowfall in November and December for the first time since 1877; in Maryland, buds appeared in apple trees, and crocuses pushed up from the ground in New Jersey; and frogs re-emerged from winter hibernation

FUTURE

CAN A PANDEMIC BE AVERTED?

• the answer is unknown

Adaptation

• the best way to prevent a pandemic would be to eliminate the influenza virus from birds

• antiviral medications to treat early cases

ADAPTATION

• global problem• global responsibility• national responsibility• organizational responsibility

– U.S. officials asked business, health, and religious groups in June, 2007 to urge Americans to prepare for a possible pandemic

• personal responsibility