Global Linkages

Biodiversity conservation

Global pandemics occur when a new disease suddenly appears against which humans have no immunity. They are often caused by a virus or other pathogens “jumping” from animals to humans. These transfers from animals to humans are called zoonoses and include infections or infectious diseases caused by viruses, bacteria, parasites, fungi and prions (proteins linked to several fatal neurodegenerative diseases). Zoonoses are transmitted through a variety of pathways, including through direct contact between animals and humans, biting insects, ingesting food and water contaminated with parasites and through the air. The Spanish flu of 1918, caused by the Influenza A virus found naturally in wild aquatic birds, claimed between Zoonoses: From animals to humans

30 and 50 million lives (Taubenberger and Morens, 2006) and is perhaps the best-known – and deadliest – example. The rabies virus and recent emerging diseases, such as the Ebola and Zika viruses, are other examples. The greatest risk of emerging zoonotic diseases is thought to occur in tropical regions, where wildlife biodiversity and land- use change is highest (Allen et al., 2017). However, given the high rate of warming in the Arctic, animal hosts or insect vectors may expand northward and survive, bringing them, together with their pathogens, into contact with human populations. A warmer climate could allow infected host species to

Probable hotspots for infectious diseases

Alaska (U.-S.)

WASHINGTON STATES

Seattle

CALIFORNIA

PACIFIC OCEAN

CANADA

UNITED STATES

PACIFIC OCEAN

ARCTIC OCEAN

MIDDLE WEST

TEXAS

EAST ASIA

MEXICO

Beijing

Shanghaï

NORTH EAST COAST

Hongkong

CHINA

Stockholm

Moscow

COLOMBIA

ECUADOR

VENEZUELA

Dacca

EUROPE

INDONESIA

PERU

INDIA

AUSTRALIA

Sydney

Madrid

SOUTH ASIA

Tehran

Mumbai

Jakarta

ISRAEL

MAGHREB

Melbourne

Abu-Dhabi

Alexandria

Riyad

EGYPT

ATLANTIC OCEAN

INDIAN OCEAN

BRAZIL

Santiago

ETHIOPIA

Land use change

NIGERIA

NORDESTE

SOUTH EAST REGION

CHILE

Kampala

WEST AFRICA

Primary drivers of past disease emergence

Rio de Janeiro

Sao Paulo

10 12 14 16 18 20 22 24 26 28 30

GREAT LAKES

Porto Alegre

SOUTH AFRICA

Agriculture industry

International travel and commerce

Medical industry

War and famine

Climate and weather

Human demography and behaviour

High risk of new infectious diseases events being observed High estimated risk of new events after factoring out reporting bias Prediction of relative risk distribution of zoonotic emerging infectious disease events

0 2 4 6 8

Public health breakdown

Other drivers

Bushmeat

Food industry

42

Global Linkages