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Globalization in Emerging Diseases 2
Content Overview
• Global Public Health• Globalization• Emerging / Re-Emerging Diseases• The Role of Globalization in Emerging/Re-
emerging Diseases
Globalization in Emerging Diseases 3
Learning Objectives
• Define global public health • Explain the role of globalization in emerging
and re-emerging diseases • Introduce emerging and re-emerging diseases
Globalization in Emerging Diseases 4
Global Public Health
• Global public health refers to improving the health of all people on the planet, not just those within one nation
• Refers to issues that affect multiple countries
Globalization in Emerging Diseases 5
Global Public Health
• An area for study, research, and practice• Affected by governmental organizations,
intergovernmental organizations, the media, international foundations, nongovernmental organizations, and transnational corporations
Globalization in Emerging Diseases 6
Globalization
• “The increased interconnectedness and interdependence of peoples and countries.”
• Increases importance of Global Public Health• Globalization includes:– Movement of people, products, services, capital,
and ideas between borders– Affected by changes in policy at the international
and national levels
Globalization in Emerging Diseases 7
Globalization History
• Dates back 2,000 years to the era of the ancient Silk Road trade route
http://en.wikipedia.org/wiki/File:Silk_route.jpg
Globalization in Emerging Diseases 8
Global Public Health History
• Middle Ages: Plague spread across Europe and Asia
• 16th Century: Smallpox and Measles introduced to the New World by European invaders
• 16th Century: Europeans took tobacco from America back to Europe
• 18th Century: Opium sold to China by Europeans
Globalization in Emerging Diseases 9
Globalization Today
• Rapidly increasing due to:– Technology– Reduced cost of transactions– Increased mobility of capital– Open economies– International architecture
• United Nations• World Bank • World Health Organization• European Union
Globalization in Emerging Diseases 11
Emerging Diseases
• Incidence of emerging diseases in humans has increased recently or threatens to increase in near future
• “Zoonotic” diseases – transmitted animals-humans• May be due to – Spread of a new pathogenic agent– Recognition of an agent previously undetected– Identification of infectious cause of a disease– Mutation or recombination allowing “jump” into humans– Changes in human habitation or land use
Globalization in Emerging Diseases 12
What Are Emerging Diseases?
• Emerging diseases are outbreaks of previously unknown diseases or known diseases whose incidence in humans increased significantly– Examples: Bartonella henselae, Ehrlichiosis,
Hendra virus, Lyme disease, and Hepatitis C
Globalization in Emerging Diseases 13
What Are Re-Emerging Diseases?
• Re-emerging diseases are known diseases that have reappeared after a significant decline in incidence– Examples: Clostridium difficile, Mumps virus,
Streptococcus Group A, and Staphylococcus aureus
Globalization in Emerging Diseases 14
Why Are There Emerging Diseases?
• Changes in Ecology– Land use (dams, agriculture, and deforestation), the
design of the built environment, and climate change• Changes in Human Demographics– Population growth and movement from rural areas to
cities, war, and immigration• Changes in Human Behavior– Sexual behavior, drug use, outdoor recreation, eating
habits, and increased use of child care centers
Globalization in Emerging Diseases 15
Why Are There Emerging Diseases?
• International Travel and Commerce• Changes in Technology and Industry– Globalization of food supplies, changes in food
processing and packaging, organ/tissue transplants, drug therapy resulting in immunosuppression, and the use of antibiotics
• Microbial Adaptation and Change• Poor Public Health Measures– Reduction of prevention programs, inadequate
sanitation, and inadequate vector control measures
Globalization in Emerging Diseases 16
Where are Diseases Emerging?
• Around the world• Typically where there are the most people• Potential hotspots of future disease
emergence:– Central America– Tropical Africa– South Asia
Globalization in Emerging Diseases 17
What Types of Diseases are Emerging or Re-emerging?
• 70% are zoonotic or vector-borne• Drug-resistant infections• Types of pathogens– Viruses– Bacteria– Protozoans– Prions
Globalization in Emerging Diseases 18
A Recent History of Emerging Diseases
• 29 microbes and infectious diseases recognized since 1973– 1976 Cryptosporidium parvum– 1977 Ebola virus– 1977 Legionella pneumophila– 1981 Toxin-producing Staphylococcus aureus– 1982 Escherichia coli O157:H7– 1982 Borrelia burgdorferi
Globalization in Emerging Diseases 19
A Recent History of Emerging Diseases
• --1983 HIV• --1983 Helicobacter pylori• --1989 Hepatitis C virus• --1992 Vibrio cholerae 0139• --1993 Sin nombre virus• --1994 Sabia virus• --1994 Mad Cow disease• --1994 Hendra virus• --1995 Human herpes virus 8• --1999 West Nile virus in US• --1999 Nipah virus• --2003 SARS virus• --???? Next??
Cells Infected with Hepatitis C Virus
Globalization in Emerging Diseases 20
Ebola
• Initially seen in 1970’s in various locations in Africa—identified as new virus
• Related to other viruses causing hemorrhagic fevers—uncontrollable bleeding
• Kills >90% of people infected• Subsequent recurrent outbreaks in west and
central Africa
Globalization in Emerging Diseases 21
Public Health Failures in Ebola Outbreaks
• Two largest outbreaks, 1976 and 1995, spread by hospitals—reuse of needles; lack of basic supplies such as gloves and masks
• Large number of victims were hospital employees
• War and poverty in developing world helped spread disease—probably isolated cases before; now epidemics
Globalization in Emerging Diseases 22
Ebola—The Future
• Natural host still not known but chimpanzees are suspected
• No cure or effective treatment as yet• Vaccine trial (DNA vaccine) is in progress—has
shown some potential in chimps
Globalization in Emerging Diseases 23
Hendra and Nipah Viruses
• Hendra isolated 1994; Australia• Nipah isolated 1999; Malaysia• Disease in animals (pigs, horses, dogs, cats)
and humans (spread from infected animals)• Natural host/reservoir – fruit bats• Severe flu-like symptoms with encephalitis
and death in some cases
Globalization in Emerging Diseases 24
Rift Valley Fever Virus
• Losses to livestock, including abortions (sheep especially susceptible)
• Primarily affects animals but also humans• Can cause severe disease and death• 1931—Rift Valley of Kenya• Major outbreaks in Africa; has spread to Saudi
Arabia and Yemen
Globalization in Emerging Diseases 25
Rift Valley Fever Distribution
• Blue, countries with endemic disease and substantial outbreaks of Rift Valley Fever (RVF); green, countries known to have some cases, periodic isolation of virus, or serologic evidence of RVF.
Globalization in Emerging Diseases 26
Transmission of Rift Valley Fever Virus (RVFV) to Humans
• Direct or indirect contact with blood or organs of infected animals
• Herders, farmers, slaughterhouse workers, veterinarians at risk
• Inoculation through broken skin or inhalation of aerosols
• Also via insects (mosquitoes and flies)
Globalization in Emerging Diseases 27
Chikungunya
• High fever, disabling joint and muscle pain, some hemorrhagic symptoms; low fatality (<0.5%)
• First isolated 1952 from humans, Aedes and Culex mosquitos in Tanzania
• Zoonotic, cycling through wildlife species via mosquitoes
• 2004-06—major human outbreak in India and islands; many European tourists infected
Globalization in Emerging Diseases 28
Chikungunya Virus Distribution
• 2007—detected in S. Europe in human case and in introduced Aedes species; has new mutation in envelope gene that enhances spread
Globalization in Emerging Diseases 29
Crimean-Congo Hemorrhagic Fever
• Characterized in Crimea in 1944 andCongo in 1969
• Ticks are reservoir and vector• Wild and domestic animals can be
hosts• Human transmission via infected
animal blood and tick bites• Symptoms: headache, fever, pain,
bleeding; 9-50% fatalities seen
Globalization in Emerging Diseases 31
Re-Emerging Diseases: Why?
• Social and political changes, changes in agricultural or industrial practices, land use, etc., can cause previously quiescent diseases to re-emerge
• Sometimes these are much more deadly than before• May have acquired resistance to previously effective
drugs• Examples:
-- Dengue: transportation, travel, and urbanization --Yellow fever: drug and insecticide resistance
Globalization in Emerging Diseases 32
Dengue
• Viral, insect transmission• Rapidly spreading, no vaccine• WHO calls “most important arboviral disease”• Fever, headache, joint/muscle pain• Up to 5% lethality• Mosquito vector expanding range
Globalization in Emerging Diseases 33
Distribution of Aedes Aegypti Mosquitoes and Dengue
Distribution of Aedes aegypti in1970, at the end of the mosquitoeradication program, and in 1997
Confirmed cases of dengue
Globalization in Emerging Diseases 34
Distribution of Countries or Areas at Risk of Dengue Transmission Worldwide, 2008
Globalization in Emerging Diseases 36
Globalization Factors that Increase Risk of Spread of Disease
• The movement of:– People– Animals / Animal Products– Food
Globalization in Emerging Diseases 37
The Movement of People
• In 2009, there were 880 million international tourist arrivals for business, leisure, and other purposes– Includes travel by air, road, rail, and sea
• If a person contracts a disease in one country, they can quickly travel around the world where they can spread the disease to new populations
Globalization in Emerging Diseases 38
The Movement of People
• Infected people quickly spread disease around the world
• People may contract a disease in one country and travel to other countries before they are symptomatic
• May result in super spreading events
Globalization in Emerging Diseases 39
Travel Medicine
• Preventing infectious diseases during international travel
• Ensuring personal safety of international travelers
• Avoiding environmental risks during travel
Globalization in Emerging Diseases 40
Travel Medicine
• Pre-travel– Risk assessment
• Traveler: Existing medical conditions, allergies, etc• Risks of travel country: itinerary, season, planned activities, etc
– Preventive counseling• Preventing illness – vaccines, sources of illness, vectors,
environmental concerns, travel medical kits, etc
– Vaccination• Post-travel– Evaluation of ill
Globalization in Emerging Diseases 41
Increased Risk of Zoonotic Diseases During Travel
• Bites/scratches from direct contact with animals• Visits to farms and agricultural areas• Local food/bushmeat/live animal markets– Slaughter, undercooked meat, raw milk, cross-
contamination, raw fish• Wilderness travel – vector-borne disease• Walking barefoot/swimming• Contamination of souvenirs• If pets travel, they can get disease that may spread
to people
Globalization in Emerging Diseases 42
Severe Acute Respiratory Syndrome (SARS)
• November 2002—first reports of new respiratory disease in Guangdong, China
• Large outbreaks in Hong Kong, Beijing, Singapore, Taiwan, and Toronto in Spring 2003
• >8000 cases with 774 deaths in 30 countries on 5 continents
Globalization in Emerging Diseases 43
Source of SARS?
• Agent is a novel coronaviruses• Connection noticed with wild food markets—
animal source?• Closely related viruses found in civets, raccoon
dogs, and bats• Bat appears to be source; amplified by
transmission in civets; following species jump, transmitted between humans
Globalization in Emerging Diseases 44
SARS Super Spreading Events
• Hospitals• Hotel• Airplane flight• Housing complex
Globalization in Emerging Diseases 48
Movement of Animals: Travel with Pets
• Reasons people travel with pets– Companionship– Reluctance to leave pet at home– Save on cost of boarding animal – Taking animal for breeding or medical care
Globalization in Emerging Diseases 49
Movement of Animals: Travel with Pets
• Risks– Pets may contract diseases, including zoonotic
diseases and bring them back home– Exposure to toxins during travel– Physical injuries and stress– Allergies• In pet• In humans traveling near pet (airplanes, trains, etc)
Globalization in Emerging Diseases 50
Movement of Animals andAnimal Products
• Global Animal Trade – Legal
• From 2000-2004, there were 37,858,179 live amphibians, birds, mammals, and reptiles legally imported to the U.S. from 163 countries.
• Highest demand for animals in U.S., People’s Republic of China, and the European Union
– Illegal• Estimated to be $5-20 billion annually• U.S. demand for illegal wildlife estimated to be same as legal
demand– $2.8 billion in 2007
Globalization in Emerging Diseases 51
Animal Trade
• Primary sources of demand:– Wildlife items for personal use• Souvenirs, exotic pets
– Products for commercial use or related to hunting• Hunting trophies
– Other sources• Zoos, research, conservation programs, scientific
education, food, pets of tourists and immigrants
Globalization in Emerging Diseases 52
Animal Trade in the U.S.
• Globalization increases demand for illegal animals– Examples• Sea turtle eggs and meat is in demand by immigrants
from Central America• Increased demand for traditional Asian medicines
Globalization in Emerging Diseases 53
Disease Outbreaks from Animal TradeAnthrax
• Anthrax from untreated, imported animal hides for drums– 1974: imported drum from Haiti, cutaneous Anthrax, patient
survives– 2006: drum maker imports hides from Côte d'Ivoire; contracts
inhalation Anthrax while making drums; patient dies– 2007: drum maker and his child get cutaneous Anthrax form
imported hides from Guinea in West Africa; both survive– 2008: drum maker in London contracts inhalation Anthrax
from contaminated animal hides from Africa; dies– 2009: gastrointestinal Anthrax contracted while playing in
drum circle; multiple drums and environment contaminated; patient survives
Globalization in Emerging Diseases 54
Anthrax
• Bacteria Bacillus anthracis• Cutaneous – handling products from infected animals• Inhalation – breathing in spores from infected animal products• Gastrointestinal – eating undercooked meat from infected animals• Weaponized – 22 cases in 2001 Anthrax spores sent through the mail• Treat with antibiotics• Vaccine is available• Anthrax does occur naturally in animals in the U.S. but much more
prevalent in Asia, the Middle East, and Africa• Importation of cattle and goat hides regulated by the USDA. Hides
must be treated to reduce risk of Anthrax.
Globalization in Emerging Diseases 55
Disease Outbreaks from Animal TradeMonkeypox
• Monkeypox– June 2003—several people in US became infected
through contact with pet prairie dogs infected by legally imported African rats
Globalization in Emerging Diseases 56
Monkeypox
• Found in 1958 among monkeys captured for research
• 1970—found in human patients in Africa• Related to smallpox; can kill up to 10% of
infected people• Isolated cases during 1980’s; didn’t seem to be
major problem—not very contagious
Globalization in Emerging Diseases 57
Monkeypox Concerns
• Can the virus become more lethal or transmissible????
• Some reports of human-human transmission• Increased host range and geographic spread• HIV infection in Africa makes monkeypox more
difficult to control
Globalization in Emerging Diseases 58
The Movement of Food
• In the United States, 15% of food is imported from more than 150 countries
• These numbers have been increasing for past 10 years
• When food is contaminated, it can cause widespread outbreaks due to the movement of food
Globalization in Emerging Diseases 59
Food and Drug Administration Globalization Act of 2009
• All facilities operating in the U.S. or importing to the U.S. must register with the FDA
• Food facilities must have plan to identify and mitigate hazards
• FDA inspects all plants on a risk-based schedule• Expanded traceback capabilities• Requires country-of-origin labeling and
disclosure• FDA may issue mandatory recalls
Globalization in Emerging Diseases 60
The Movement of Food
• Illegal bushmeat trade from Africa– $50 million annually sold worldwide– Sold to some communities in U.S.– Diseases associated with bushmeat• Ebola• HIV/AIDS• Monkeypox • SARS
Globalization in Emerging Diseases 61
The Movement of Food
• Legal food imports may also cause disease– 1996: Cyclospora is strawberries from Guatemala– 2000-2002: Salmonella in cantaloupe from
Mexico– 2008: Salmonella in peppers from Mexico– 2011: Salmonella in Papayas from Mexico
Globalization in Emerging Diseases 62
The Benefits of Globalization Regarding Disease Outbreaks
• Shared research/medical advances• Global surveillance and disease response• Global Health Initiatives
Globalization in Emerging Diseases 64
Global Surveillance & Disease Response
• Animal Diseases/Zoonotic Diseases– Global Early Warning and Response System
(GLEWS)• Human Diseases– Global Outbreak Alert and Response Network
(GOARN)
Globalization in Emerging Diseases 65
Animal Disease Outbreak Alerts
• Global Early Warning and Response System (GLEWS)– For Major animal diseases, including zoonotic diseases– Developed by:
• World Health Organization (WHO)• Food and Agricultural Organization of the United Nations
(FAO)• World Organization for Animal Health (OIE)
– Goals:• Earlier detection• Coordinated response
Globalization in Emerging Diseases 66
GLEWS Alerts in 2010
• Rabies in Peru, Trinidad, and Tobago• Nipah Virus in Bangledesh• H5N1 Influenza in Vietnam, Romania, Bulgaria• Highly pathogenic avian influenza in China and Japan• Rift Valley Fever in South Africa, Saudi Arabia• Foot and Mouth Diseases in Republic of Korea• Glanders in Bahrain• Venezuelan Equine Encephalomyelitis in Panama• African Swine Fever in Armenia and Chad• Anthrax in Bangladesh
Globalization in Emerging Diseases 67
Human Disease Outbreak Response
• Global Outbreak Alert and Response Network (GOARN)– Combat international spread of outbreaks among
humans– WHO, UNICEF, Red Cross, and others
Globalization in Emerging Diseases 68
GOARN Response to SARS
• WHO recognized outbreak in March 2003; declared Global Alert
• Goal was to allow all countries time to prepare for possible global epidemic
• Created network of 13 labs in ten countries– Identified virus associated with SARS in 2 weeks– Genome sequenced in 2 more– (Took 2 years to identify HIV as cause of AIDS in 80’s)
Globalization in Emerging Diseases 69
GOARN Alerts in 2010• Avian Influenza in Egypt, Indonesia, China, Cambodia, Vietnam• Cholera in Haiti, Pakistan, Central Africa• Polio in Central Asia, the North Caucasus Federal Region of the
Russian Federation, Congo, Angola, Tajikistan• Crimean-Congo haemorrhagic fever (CCHF) in Pakistan • Dengue in Pakistan• Yellow Fever in Senegal, Congo, Cameroon, Guinea, Côte d'Ivoire• Plague in Peru• Lead poisoning in Nigeria from mining• Acute Haemorrhagic Fever in Congo• Rift Valley Fever in South Africa• Meningococcal disease in Chad
Globalization in Emerging Diseases 70
Global Health Initiatives
• Roll Back Malaria– Launched in 1998– More than 500 partners– Vision: World free from Malaria
• Stop TB– Launched in 1998
• Global Alliance for Vaccines and Immunization– Launched in 2000 – Bring vaccines to developing countries
• Hepatitis B, Childhood meningitis, Yellow Fever, and respiratory infections
Globalization in Emerging Diseases 71
Summary
• Summary ideas are still needed here.
• © by Kansas State University
Globalization in Emerging Diseases 72
References
• The WHO Global Health Observatory Map Gallery
• The US Centers for Disease Control and Prevention
• http://www.ispub.com/journal/the_internet_journal_of_biological_anthropology/volume_1_number_1_10/article_printable/how_to_deal_with_emerging_and_re_emerging_infectious_diseases_globally.html
• http://www.ispub.com/ostia/index.php?xmlFilePath=journals/ijba/vol1n1/infections.xml
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