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Global Trade and Infections

Global Trade and Microbial Traffic Ann Marie Kimball, MD., MPH School of Public Health and Community Medicine University of Washington. Global Trade and Infections. Conceptual framework, background

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Global Trade and Infections

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  1. Global Trade and Microbial Traffic Ann Marie Kimball, MD., MPHSchool of Public Health and Community MedicineUniversity of Washington

  2. Global Trade and Infections • Conceptual framework, background • Summarize four illustrative infections: HIV/AIDS, enteric infections from sprouts, cyclospora from rasberries, BSE from beef products • Examine surveillance, prevention and control options extant through the WHO,WTO

  3. “Trade-Related Infection” an infectious disease whose • Emergence is hastened by ecological pressure of “scaling up” production to meet international trade markets • Transmission is broadened through transportation or trade in goods • Economic impact is large in terms of trade disruption

  4. Uneven Access to Water/Sanitation

  5. Uncontrolled Urbanization

  6. International Agricultural Trade, 1961-2000 US Dollars (millions) Years Source: UN Food and Agriculture Organization

  7. ***Value of food trade in US alone in 1994: $266 billion

  8. Global Trade /Globalization • Major increases in global trade, particularly in meats and fresh produce over the past thirty years • Increased traffic of goods an humans overlayed on inadequate public health infrastructure, and increasing population, urbanization

  9. Human Disease as Travelers on the Global Express

  10. Examples of Global Epidemics • HIV/AIDS- factors of urbanization, transportation, technology,trade, • Enteric Disease • Bovine Spongiform Encephalopathy (New variant Jacob Creutzfeldt Disease)

  11. Eastern Europe & Central Asia 1 million Western Europe 560 000 North America 940 000 East Asia & Pacific 1 million North Africa & Middle East 440 000 South & South-East Asia 6.1 million Caribbean 420 000 Sub-Saharan Africa 28.1 million Latin America 1.4 million Australia & New Zealand 15 000 Total: 40 million Source: UNAIDS, 12/01 Adults and Children Estimated to be Living with HIV/AIDS as of end 2001

  12. Factor VIII development, late 1970’s 1 unit derived from 20,000 units of plasma US hemophiliac HIV epidemic 1982-85, (followed hepatitis epidemic) US main exporter of factor VIII in 1980’s Japan epidemic began with commercial product introduction 1993 64% of HIV/AIDS cases in Japan in hemophiliacs HIV in Factor VIII, IX

  13. Alpha Therapeutic (owned by Green Cross, Japan) Armour Pharmaceutical Hyland of Travenol Labs (later Baxter) Cutter Division, Miles labs (later Bayer) 1981 sales $10 million, 1988 $38m 1982 sales $51m,1988 $125m. 1982 sales $60 million, 1988 $98 m. 1982 sales $69 million, 1988 $123m. Big Four Pharma Plasma to Blood Products Fractionation

  14. 1,600,000 1,400,000 1,200,000 1,000,000 Blood Fractions & 800,000 Modified 600,000 Immunological Products 400,000 200,000 0 1993 1995 1997 1999 1989 1991 US Export of Blood Fractions & Modified Immunological Products1989 – 2000 1,000 US Dollars Years United States International Trade Commission, Interactive Tariff and Trade DataWeb

  15. Sprouts and Enteric Disease • Global trade provides access to fresh produce year-round • Consumers seek fresh fruits and vegetables as part of a healthy diet • Unlike bacteria traveling on meat, those on produce often escape cooking “kill-step” • Seed contamination probable, bacteria multiply in sprouting

  16. Sprout Production Process • Seeds purchased from a distributor and sprouted locally • Several opportunities for contamination • Provides ideal conditions for bacterial growth

  17. Many unexpected cases • Serotype specific CDC surveillance system begun • Salmonella stanley isolates were the cause of numerous reports of gastroenteritis in 1995

  18. Three S. stanley outbreaks • Two states • Michigan • Arizona • SALM-Net • Finland • from Mahon, BE et al, JID 1997;175:876

  19. Identifying a common source • Case control studies conducted in each location • Confirmed the role of alfalfa sprouts in transmitting the variant Salmonella

  20. outbreak sporadic Molecular Epidemiology • PFGE & antibiogram • common source for the three outbreaks • Unique isolate found at all locations 1–5, outbreak isolates (1 and 2, Arizona; 3, Michigan; 4, Finland; 5, Ohio). Lanes 7–10, sporadic isolates not linked to outbreak (7, Arizona;8, Missouri; 9, Finland; 10, Virginia). Lane 6, l ladder molecular weight marker.

  21. Tracebacks • Case interviews • Trace contaminated sprouts to their source • identify retail outlets and dates of purchase • determine shippers and growers who provided sprouts • Invoices and delivery records identify seed suppliers, lot numbers, and dates of sprouting • 50 successful tracebacks • 9 growers used single U.S. supplier • seeds from Netherlands distributor • combination of lots from Hungary, Pakistan, & Italy

  22. No. of Location of Typeof Likely Source of Year Pathogen Cases Outbreak Sprout Contamination Reference 1988 S. Saint - Paul 143 United Mung Seed O'Mahony et al., 1990 Kingdom Bean 1989 S. Gold - C oast 31 United Cress Unkown Joce et al., 1990 Kingdom 1994 S. 492 Sweden, Alfalfa Seed Ponca et al., 1995 Bovismorbificans Finland Puohiniemi et al., 1997 1995 S. Stanley 114 Finland Alfalfa Seed Kontiainen et al., 1996 Mahon et al., 1997 1995 S. Newpor t ???? Denmark, Alfalfa Seed OregonHealth Division, 1995 Canada Aabo and Baggesen, 1997 1996 . Ecoli O157:H7 >6,000 Japan Radish Unknown Nat'l Inst. Infect. Dis. and Infect. Dis. Ctrl Div., Ministry of Health and Welfare of Japan, 1997 1997 S. Meleagrid is 78 Canada Alfalfa Seed Buck et al., 1998 1997 E. coli O157:H7 126 Japan Radish Unkown Gutierrez, 1997 Sprouts: an international threat

  23. Cylcospora cayetanesis • Emerging infection • First documented case in 1977 • Confirmed coccidian parasite in 1993 • Received its name in 1994 • Outbreaks starting in 1995

  24. Lifecycle • Not completely understood • Humans are only known host • Infectious spores are ingested • Prolonged GI illness • Oocysts excreted in feces

  25. “Sentinel” Outbreaks in 1995 • First North American outbreaks • New York and Florida • Three small clusters • Inconclusive investigation • Suggested raspberries and strawberries

  26. Difficult Detective Work • Trace-back and case-control studies • Delayed GI illness • Delayed diagnosis • Difficult to remember food intake • Fresh fruit no longer available • No brand name recognition

  27. Outbreak in 1996 • 1465 cases in US and Canada • 55 event clusters • Guatemalan Raspberries were implicated • Widespread contamination prior to export • Multiple farms • Varied ports of entry • Many distribution patterns within North America • Herwaldt B et al NEJM 1997

  28. Canada and US both experienced clusters of disease 737 lab confirmed cases clustered seasonally

  29. Cultivation Related Contamination • Infected humans contaminate water sources • Water used in crop treatments • Insecticides • Fertilizers • Contaminated raspberries exported

  30. Virulence Factors • Single raspberry can cause infection • Simple water wash ineffective • Resistant to Chlorine treatment of water • Oocyst is very strong and can survive difficult environments • Food-borne and water-borne transmission

  31. Outbreak in 1997 • Guatemalan Berry Commission implemented voluntary control measures • Hygiene • Sanitation • Water sources • Another multi-state, multi-cluster outbreak in the U.S, Canada • Suspension of export by Guatemala to N. American markets ended the outbreak

  32. Despite measures, 41 new clusters occurred Shipments were stopped from Guatemala end of May, 1997 (voluntary)

  33. Outbreak in 1998 • FDA prohibited importation of Guatemalan raspberries • “Interventional study” where Canada was exposed and the US was the control • No outbreak in the US • Multi-cluster outbreak in Canada

  34. Guatemalan Raspberries • The epidemiologic evidence was strong • Tighter controls within Guatemala decreased number of outbreaks in following years • Definitive control with trade import restriction by U.S.

  35. The Guatemalan Incident • Unsafe cultivation in resource poor setting of a newly introduced cash crop • Role of surveillance • Is trade restriction the only remedy?

  36. BSE/nCJD Disease • Change in rendering, husbandry practice implicated in emergence • silent global circulation in product • Novel agent (prion), long latency,

  37. Cases of vCJD, worldwide, as of end of August 2001 30 numberof cases 25 20 15 10 5 0 1995 1996 1997 1998 1999 2000 2001 Source: UK, France

  38. Bovine Spongiform Encephalopathy, United Kingdom

  39. BSE and vCJD: potential exposure through international trade, early 1990s Live cattle Meat and bone meal Food containing beef Pharmaceuticals Blood and blood products Human and bovine tissue used in biologicals

  40. 900,000 800,000 700,000 600,000 500,000 UK Bovine Meat 400,000 UK Beef and Veal 300,000 200,000 100,000 0 1979 1982 1985 1988 1991 1994 1997 1970 1973 1976 UK Beef Exports1970 - 1999 1,000 US Dollars Years Food and Agriculture Organization of the United Nations, FAOSTAT

  41. Contaminated Meat • Numerous examples of enteritis outbreaks from contaminated meat worldwide and in U.S.(Ecoli O157, Salmonella typhimurium DT104) Coincides with marked increase in meat and meat product trading worldwide

  42. 7,000,000 6,000,000 5,000,000 4,000,000 US Bovine Meat 3,000,000 Total US Meat and 2,000,000 Edible Offal 1,000,000 0 1993 1995 1997 1999 1989 1991 US Meat Exports1989 – 2000 1,000 US Dollars Years United States Department of Agriculture, Foreign Agriculture Service

  43. E. Coli in Meat, BSE analogies Changes in production to dramatically increase yield, and economize in expense predated outbreak emergent infections linked to meat products for human consumption. Was Global Trade a driver?

  44. “Primary prevention” prevention of emergence of new infections “Secondary Prevention” through prevention of dissemination through trade “Surveillance and timely control” through enhanced surveillance systems What is new in Trade - related surveillance for trade related infections? Addressing Direct Trade Related Infections

  45. Public Health and Trade • WHO • Improve health • Prevent/control disease • Provides health input to • Codex Alimentarius • standards • Develops and manages • health regulations (IHR) • WTO • Establish trade rules • Solve trade problems • Codex • Alimentarius • Sets food • standards • SPS Agreement • Recognizes Codex • Alimentarius standards as the • reference for food safety • requirements when they affect • health and international trade • IHR • WHO establishes IHR • under Constitution

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