360 likes | 506 Views
Risk of FMD-virus Introduction into the US via Cheese Importation (from around the World). Anwar Ahmad, T. Habtemariam, O. Ayanwale, B. Tameru, D. Nganwa CCEBRA, TU; M. Modarres CTRS, University of Maryland; and Richard Fite USDA/APHIS. Objectives.
E N D
Risk of FMD-virus Introduction into the US via Cheese Importation(from around the World) Anwar Ahmad, T. Habtemariam, O. Ayanwale, B. Tameru, D. Nganwa CCEBRA, TU; M. Modarres CTRS, University of Maryland; and Richard Fite USDA/APHIS
Objectives • To develop a quantitative risk assessment model to determine the risk of introduction of foot and mouth disease (FMD) virus into the United States via cheese importation from various parts of the world
Foot-and-mouth Disease • Foot-and-mouth disease (FMD) is a highly infectious disease of cloven footed animals such as cattle, swine, goats, sheep, buffalo, bison, yak, camels, deer, llamas, reindeer, moose, elk, vole, rats. • It is the most contagious disease that is confined to above named animals in its clinical manifestations. Shows much earlier in pigs and sheep than in cattle. • It does NOT affect human being. However, people handling infected animals may harbor the virus in their nasopharynx for up to 24 hours.
Foot-and-Mouth Disease Virus • CAUSATIVE AGENT • It is caused by a virus called FMD virus. • There are 7 distinct types of this virus: • O, A, C, SAT 1, SAT 2, SAT 3 and Asian type 1 • The USA is as of today free of FMD virus.
Clinical Manifestation • After 2-5 days of incubation (may be up to 18 days) in a receptive host, there is high fever. • May be absent or unnoticed in cattle • Pigs showed more rapidly: eruption of vesicles in the mouth and on the feet • Vesicles soon filled with colored fluid • Mouth, tongue, gums, lips become tender and sore • Salivation • Starvation & Dehydration (for inability to eat and drink) • Complications follow e.g. abortion, mastitis, pneumonia, septicemia
FMD Virus • FMD virus in the dirt of a shed is viable for up to 14 days • In animal refuse/dung for 39 days • Inside manure for 6 days • On the surface of manure during summer for 28 days • In winter for 67 days • Can also survive up to 15 weeks in feed • On cattle hair for 4 weeks
FMD Virus • In waste water up to 103 days • Can survive in milk and cheese for several days and months • Dies at pH of 6 and below • Dies at pasteurization temperature (74oC for 30sec) • All the serotypes in naked forms can easily be destroyed by acids like acetic, formic, sulfuric and phosphoric acids, alkali like 1% of Sodium Hydroxide, 1% of sodium metasilicate and 4% of Sodium carbonate, glutaraldehyde and formalin • The virus can also be destroyed by heat, UV lights, gamma radiation and X-rays
WORLDWIDE FMD AND THE US CHEESE IMPORTATION • So far, USA is free of FMD. • No FMD has been reported in any part of this country for decades. • However, the risk of reintroduction of this virus into the country is real since US imports a lot of cheese into the country annually. • As of October 2001, the US has imported a cumulative amount of over 1000 metric tons of cheese from all over the world including neighboring South American countries some of which have FMD, endemic in their livestock.
POLITICS AND SCIENCE • An “International Conference on Perspectives for the Eradication of Foot and Mouth Disease in the Next Millennium and its Impact on Food Security and Trade in the Americas” was held in Brasilia, Brazil, from 11 to 12 July 1996
POLITICS AND SCIENCE • The event was organized by the Pan-American Health Organization/World Health Organization (PAHO/WHO), the Office International des Epizooties (OIE) and the Food and Agriculture Organization of the United Nations (FAO). In addition to Ministers of Agriculture of the Americas or their representatives, there was large participation of private producers and representatives of institutions involved in programs for the eradication of foot and mouth disease.
WHAT FOLLOWED THE PAHO/WHO/OIE CONFERENCE? Questions: • Do we feed garbage to our animals in the US? • Do we treat garbage before feeding to animals ? • How does the garbage treated ? • What is the consequence of FMD virus in garbage-fed livestock industry
Foot-and-Mouth Disease • FMD is one of the most contagious viral diseases of cloven footed animals (Cattle, Sheep, Swine, Goat, Sheep, Deer, etc.)
Foot-and-Mouth Disease in UK Spring 2000 UK outbreak has devastated the livestock industry in particular and the economy in general with 2030 confirmed cases
Foot-and-Mouth Disease in UK • 3,195,000 slaughters • Overall ~$10 Billion price tag • US 10X the UK livestock population
Foot-and-Mouth Disease Virus FMD virus is a member of the Aphthovirus genus of the Picornaviridae family
Foot-and-Mouth Disease Virus • There are seven distinct immunological serotypes: O, A, C, SAT 1, SAT 2, SAT 3 and Asian-1 • FMD virus is a relatively resistant virus
Foot-and-Mouth Disease Virus • FMD virus may be excreted in the milk of animals • The virus survival in milk depends on the temperature, the bacterial count, and pH
FMD Virus Distribution • OIE maintains the worldwide FMD virus status based upon vaccination practices In April, Phoenix the calf is spared from the cull after surviving for five days under a mound of slaughtered cattle
Risk Analysis Risk Management Risk Assessment Risk Communication
Quantitative Risk Assessment • Hazard Identification • Likelihood Characterization • Magnitude (Quantification), if the hazard occurs *Magnitude of the damage in biological and economic terms
Quantitative Risk Assessment • The process of identifying a hazard and evaluating the risk of a specific hazard, whether in absolute or relative term • It includes estimates of uncertainty and is based on the best reasonably obtainable and sound scientific knowledge available
Methodology Initiating Event: Cheese Importation into the US No Risk Is the cheese imported from FMD country? NO YES Risk Propagated
Methodology • Categorize the exporting countries into FMD vs. non-FMD based upon OIE recommendations (http://www.oie.net)
Methodology • This categorization with the past 10 years historical data of the major cheese exporting countries provide us the proportion of the cheese coming from FMD countries and the probability of risk associated with that
Methodology Is the cheese made from pasteurized milk? No Risk YES NO Risk Propagated
Cheese Varieties • Due to numerous cheese varieties manufactured around the world, it is impossible to determine the risk from individual varieties of cheese • After consulting the cheese expert on the subject matter we have divided cheeses into five broad categories based upon the processes and the equipment rather moisture or fat contents
Cheese Varieties • Category 1: Cheddar - Dry Salted varieties (the salt is applied as dry) - Vat, Belt system, Block formation • Category 2: Semi hard - Brine Salted, Gouda, Edam, Swiss, Parmesan (the salt is applied as a brine) - Vat, Block formation, Pressing, Brining • Category 3: Mozzarella - Pizza cheese - Vat, Belt system, Cooker stretcher, cooling tunnel, brining system.
Cheese Varieties • Category 4: Soft - Cottage (can also be camembert) Vat, De wheying system, Washing, Creamer, Dressing, Filling machine • Category 5: Specialty - Goats milk, blue vein, quarg etc can be a range of different equipment
Methodology Is the cheese matured at pH <= 6.0 No Risk YES NO Risk Propagated
Methodology Is the cheese aged > 60 days? No Risk YES NO Risk Propagated
Methodology Initiating Event: Cheese Importation into the US NO No Risk Is the cheese imported from FMD country? YES Is the cheese pasteurized at desired temp and duration? Is the cheese made from pasteurized milk? YES No Risk Is the cheese matured at pH <= 6.0 No Risk YES YES No Risk Is the cheese aged > 60 days? FMD virus introduction via cheese importation into US
Results • This is work in progress • In consultations with: • Experts • Universities • Government • Industry • Other countries