Mad cow disease other names. Mad Cow Disease: Understanding BSE and Its Impact on Global Health

21.08.202308.07.2023 by alexxlab

What is Mad Cow Disease. How does Bovine Spongiform Encephalopathy spread. What are the risks of BSE to human health. How is BSE prevented and controlled. What are the economic impacts of BSE outbreaks. How has BSE affected international trade policies. What are the current global surveillance efforts for BSE.

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The Origins and Nature of Mad Cow Disease

Mad Cow Disease, scientifically known as Bovine Spongiform Encephalopathy (BSE), is a progressive neurological disorder affecting cattle. This fatal brain disease belongs to a family of conditions called transmissible spongiform encephalopathies (TSEs) or prion diseases. Prions, misfolded proteins that can trigger normal proteins in the brain to fold abnormally, cause these diseases.

BSE first emerged as a significant concern in the United Kingdom in the 1980s. The disease’s origin is believed to be linked to the practice of feeding cattle with meat and bone meal derived from other ruminants, which may have contained the infectious prion protein. This practice, now banned in many countries, allowed the disease to spread within cattle populations.

Symptoms and Progression of BSE

How does BSE manifest in cattle? The disease typically has a long incubation period of 4-6 years. Early symptoms include:

Changes in behavior and temperament
Abnormal posture
Lack of coordination
Difficulty in rising from a lying position

As the disease progresses, affected cattle may experience tremors, weight loss, and decreased milk production. Eventually, the animal becomes unable to stand and dies. The spongiform appearance of the brain tissue post-mortem is a hallmark of the disease.

The First U.S. Case: A Turning Point in BSE Surveillance

On December 23, 2003, the United States Department of Agriculture (USDA) announced a presumptive diagnosis of the first known case of BSE in the United States. This landmark case involved an adult Holstein cow from Washington State. The international reference laboratory in Weybridge, England, confirmed the diagnosis on December 25, marking a significant moment in U.S. agricultural history.

Trace-back investigations, based on ear-tag identification and genetic testing, revealed that the BSE-infected cow had been imported from Canada in August 2001. This finding highlighted the importance of robust international surveillance and trade policies in controlling the spread of BSE.

Immediate Response and Recall

How did authorities respond to this first U.S. case of BSE? The reaction was swift and comprehensive:

The USDA’s Food Safety and Inspection Service (FSIS) recalled beef from cattle slaughtered in the same plant on the same day as the BSE-positive cow.
An epidemiologic investigation was launched in cooperation with Canadian agricultural authorities to determine the source of the disease.
The incident triggered a reevaluation of BSE surveillance and prevention measures in the United States.

This case underscored the critical importance of having effective systems in place for detecting and responding to potential BSE cases, even in countries previously considered BSE-free.

BSE and Human Health: The vCJD Connection

The discovery of BSE raised significant concerns about potential risks to human health. Strong evidence indicates that BSE has been transmitted to humans, primarily in the United Kingdom, causing a variant form of Creutzfeldt-Jakob disease (vCJD).

Variant Creutzfeldt-Jakob disease (vCJD) is a rare and fatal human neurodegenerative condition. It is believed to be caused by consumption of beef products contaminated with the BSE agent. As of December 1, 2003, a total of 153 vCJD cases had been reported worldwide, with 143 of these occurring in the United Kingdom.

The Species Barrier and Risk Assessment

Despite the large number of cattle potentially infected with BSE in the United Kingdom (over 1 million), the number of human vCJD cases has been relatively low. This suggests the existence of a substantial species barrier that protects humans from widespread illness.

Is there a significant risk of vCJD in the United States? The risk to human health from BSE in the United States is considered extremely low. This assessment is based on several factors:

Stringent import restrictions on live ruminants and ruminant products from BSE-affected countries
The ban on feeding ruminant-derived proteins to cattle
Comprehensive surveillance and testing programs
Removal of specified risk materials (SRMs) from the food supply

Surveillance and Monitoring: Keeping BSE at Bay

Following the first U.S. case of BSE, surveillance efforts were significantly enhanced. The Centers for Disease Control and Prevention (CDC) plays a crucial role in monitoring trends and current incidence of CJD in the United States.

How does the CDC monitor for potential BSE-related human cases? The process involves several key components:

Analyzing death certificate information from U.S. multiple cause-of-death data
Conducting follow-up reviews of clinical and neuropathology records of CJD decedents younger than 55 years of age
Collaborating with the National Prion Disease Pathology Surveillance Center at Case Western Reserve University

The National Prion Disease Pathology Surveillance Center provides free, state-of-the-art diagnostic services to U.S. physicians and helps monitor for emerging forms of prion diseases, including vCJD.

International Collaboration and Resources

Effective BSE surveillance requires international cooperation and the sharing of resources. Several key organizations contribute to this effort:

United States Department of Agriculture’s (USDA) BSE Surveillance Information Center
Food and Drug Administration (FDA) Bovine Spongiform Encephalopathy resources
CDC Prion Diseases information
National Institutes of Health (NIH) National Institute of Neurological Disorders and Stroke (NINDS) Creutzfeldt-Jakob Disease Information Page

These resources provide valuable information for researchers, healthcare professionals, and the public, ensuring a coordinated approach to BSE surveillance and prevention.

Prevention Strategies: Safeguarding Against BSE

Preventing the spread of BSE is crucial for protecting both animal and human health. Various measures have been implemented globally to reduce the risk of BSE transmission and exposure.

Import Restrictions and Feed Bans

One of the primary prevention strategies involves strict regulations on the importation of live ruminants and certain ruminant products. In the United States, severe restrictions were placed on imports from countries where BSE was known to exist. These restrictions were later extended to include all European countries.

What is the most crucial step in preventing BSE spread? The ban on feeding ruminant-derived proteins to cattle is considered the most important measure. This practice, which is believed to have led to the initial spread of BSE, is now prohibited in many countries worldwide.

Surveillance and Testing

Robust surveillance programs are essential for early detection of BSE cases. These programs typically involve:

Testing of high-risk cattle, including those showing neurological symptoms
Random testing of healthy cattle at slaughter
Continuous monitoring of CJD cases in humans

Advanced diagnostic techniques, including histopathology and immunohistochemical testing, are used to confirm BSE cases.

Economic Impact and Trade Implications of BSE

The discovery of BSE cases can have severe economic consequences for affected countries. The immediate impact often involves trade restrictions and bans on beef exports, leading to significant financial losses for the cattle industry.

Market Reactions and Consumer Confidence

How do BSE outbreaks affect consumer behavior? BSE scares can lead to:

Reduced domestic consumption of beef products
Shifts in consumer preferences towards alternative meats
Increased demand for organic or grass-fed beef

These changes can have long-lasting effects on the beef industry, even after the immediate crisis has passed.

Cost of Prevention and Surveillance

Implementing and maintaining BSE prevention measures and surveillance programs require significant financial investment. Costs include:

Testing equipment and procedures
Training of personnel
Compensation for farmers in case of herd culling
Research and development of new diagnostic tools

While these costs are substantial, they are generally considered necessary to protect public health and maintain consumer confidence in the beef industry.

Global Perspectives: BSE’s Impact on International Trade

The emergence of BSE has had far-reaching effects on international trade policies and practices. Countries have implemented various measures to protect their domestic cattle populations and ensure food safety.

Trade Restrictions and Negotiations

How have countries responded to BSE in terms of trade? Common responses include:

Immediate bans on beef imports from affected countries
Negotiations for resuming trade based on risk assessments
Implementation of traceability systems for cattle and beef products

These measures have led to complex international negotiations and the development of new trade agreements that take BSE risk into account.

Global Standards and Harmonization

The World Organization for Animal Health (OIE) plays a crucial role in setting international standards for BSE control and prevention. These standards help countries to:

Assess their BSE risk status
Implement appropriate control measures
Facilitate safe trade in cattle and beef products

Harmonization of BSE-related regulations across countries is an ongoing process aimed at ensuring food safety while minimizing unnecessary trade disruptions.

Future Challenges and Research Directions

While significant progress has been made in understanding and controlling BSE, several challenges and areas for future research remain.

Improving Diagnostic Tools

Current diagnostic methods for BSE are primarily post-mortem. Developing reliable ante-mortem tests for BSE in cattle and vCJD in humans is a key research priority. Such tests could allow for earlier detection and better disease management.

Understanding Prion Biology

What are the key questions in prion disease research? Scientists are focusing on:

The mechanisms of prion protein misfolding and propagation
Factors influencing the species barrier in prion diseases
Potential therapeutic approaches for prion diseases

Advances in these areas could lead to breakthroughs in preventing and treating BSE and related conditions.

Emerging Prion Diseases

Vigilance is required for potential new forms of prion diseases that may emerge. Ongoing surveillance and research are essential to identify and respond to new threats promptly.

In conclusion, the story of Mad Cow Disease illustrates the complex interplay between animal health, human health, and global trade. While significant progress has been made in controlling BSE, continued vigilance, research, and international cooperation are essential to protect both animal and human populations from this and other potential prion diseases.

BSE Cases Identified in the United States BSE (Bovine Spongiform Encephalopathy) | Prion Diseases

On December 23, 2003, the U.S. Department of Agriculture (USDA) announced a presumptive diagnosis of the first known case of BSE in the United States. It was in an adult Holstein cow from Washington State. This diagnosis was confirmed by an international reference laboratory in Weybridge, England, on December 25. Trace-back based on an ear-tag identification number and subsequent genetic testing confirmed that the BSE-infected cow was imported into the United States from Canada in August 2001.

Because the animal was non-ambulatory (a “downer cow”) at slaughter, brain tissue samples were taken by USDA’s Animal and Plant Health Inspection Service as part of its targeted surveillance for BSE. However the animal’s condition was attributed to complications from calving. After the animal was examined by a USDA Food Safety and Inspection Service (FSIS) veterinary medical officer both before and after slaughter, the carcass was released for use as food for human consumption. During slaughter, the tissues considered to be at high risk for the transmission of the BSE agent were removed.

On December 24, 2003, FSIS recalled beef from cattle slaughtered in the same plant on the same day as the BSE positive cow. (see Bovine Spongiform Encephalopathy in a Dairy Cow—Washington State, 2003.)

Preliminary Investigation Suggests BSE-Infected Cow in Washington State Was Likely Imported from Canada

On December 23, 2003, the U.S. Department of Agriculture (USDA) announced a presumptive diagnosis of bovine spongiform encephalopathy (BSE, or “mad cow” disease) in an adult Holstein cow from Washington State. Samples were taken from the cow on December 9 as part of USDA’s BSE surveillance program. The BSE diagnosis was made on December 22 and 23 by histopathology and immunohistochemical testing at the National Veterinary Services Laboratory, Ames, Iowa. The diagnosis was confirmed by an international reference laboratory in Weybridge, England, on December 25. Preliminary trace-back based on an ear-tag identification number suggests that the BSE-infected cow was imported into the United States from Canada in August 2001.

USDA, in close cooperation with Canadian agricultural authorities, has launched an epidemiologic investigation to determine the source of the disease. Beef from the slaughtered cow had been processed for human consumption. On December 23, 2003, the Food Safety and Inspection Service (FSIS), USDA announced the recall of all beef from cattle slaughtered on December 9 at the involved slaughter plant.

Strong evidence indicates that BSE has been transmitted to humans primarily in the United Kingdom, causing a variant form of Creutzfeldt-Jakob disease (vCJD). In the United Kingdom, where over 1 million cattle may have been infected with BSE, a substantial species barrier appears to protect humans from widespread illness. As of December 1, 2003, a total of 153 vCJD cases had been reported worldwide; of these, 143 cases had occurred in the United Kingdom. The risk to human health from BSE in the United States is extremely low.

CDC monitors the trends and current incidence of CJD in the United States by analyzing death certificate information from U.S. multiple cause-of-death data compiled by the National Center for Health Statistics. With the support of the Council of State and Territorial Epidemiologists, CDC conducts follow-up review of clinical and neuropathology records of CJD decedents younger than 55 years of age. In addition, during 1996-1997, in collaboration with the American Association of Neuropathologists (AANP), CDC established the National Prion Disease Pathology Surveillance Centerexternal icon at Case Western Reserve University in Cleveland, Ohio. This pathology center provides free, state-of-the-art diagnostic services to U.S. physicians. It also helps to monitor the possible occurrence of emerging forms of prion diseases, such as vCJD, in the United States. For more information about the center visit its website at:

United States Department of Agriculture’s (USDA): BSE Surveillance Information Centerexternal icon
FDA Bovine Spongiform Encephalopathy external icon
CDC Prion Diseases
NIH NINDS Creutzfeldt-Jakob Disease Information Pageexternal icon

Prevention BSE (Bovine Spongiform Encephalopathy) | Prion Diseases

Prevention Measures against BSE Spread

To prevent BSE from entering the United States, severe restrictions were placed on the importation of live ruminants, such as cattle, sheep, and goats, and certain ruminant products from countries where BSE was known to exist. These restrictions were later extended to include importation of ruminants and certain ruminant products from all European countries.

Because the use of ruminant tissue in ruminant feed was probably a necessary factor responsible for the BSE outbreak in the United Kingdom and because of the current evidence for possible transmission of BSE to humans, the U.S. Food and Drug Administration instituted a ruminant feed ban in June 1997 that became fully effective as of October 1997. As of October 26, 2009, a regulation issued by FDA in April 2009 came into effect establishing an enhanced BSE-related feed ban in the U.S. This enhanced feed ban will further harmonize BSE feed control measures in the U.S. with those in Canada (see below). In addition, FDA continues to enforce its important 1997 mammalian-to-ruminant feed ban through its BSE inspection and BSE feed testing programs.

As of July 12, 2007, an enhanced BSE-related feed ban came into effect in Canada. CFIA established this ban to more effectively prevent and quickly eliminate BSE from Canada. The enhanced ban prohibits most proteins, including potentially BSE infectious tissues known as “specified risk materials” (SRM) from all animal feeds, pet foods, and fertilizers, not just from cattle feed as required by the ban instituted in 1997. The 1997 feed ban in Canada was similar to the feed ban instituted in the United States that same year. As recently reported by CFIA, removing SRM from the entire animal feed system addresses risks associated with the potential contamination of cattle feed during production, distribution, storage, and use. Applying the same measure to pet food and fertilizer materials addresses the possible exposure of cattle and other susceptible animals to these products. With this ban in place, CFIA expects BSE should be eliminated from the Canadian cattle herd by about the year 2017.

In late 2001, the Harvard Center for Risk Assessment study of various scenarios involving BSE in the U.S. concluded that the FDA ruminant feed rule provides a major defense against this disease.

BSE/TSE Action Plan of the Department of Health and Human Services (DHHS)

On August 23, 2001, the Department of Health and Human Services (HHS) issued a department-wide action plan outlining steps to improve scientific understanding of BSE and other transmissible spongiform encephalopathies (TSEs). The action plan has four major components:

Surveillance for human disease is primarily the responsibility of CDC.

Protection is primarily the responsibility of the Food and Drug Administration (FDA).

Research is primarily the responsibility of the National Institutes of Health (NIH).

Oversight is primarily the responsibility of the Office of the Secretary of DHHS.

Read the Department of Health and Human Services press release: USDA and HHS Strengthen Safeguards Against Bovine Spongiform Encephalopathyexternal icon

what you need to know about mad cow disease

The Department of Veterinary Medicine of the Sverdlovsk Region warns owners of cattle about the danger of importing into the country from disadvantaged zones or countries of breeding stock, meat, canned food, offal and semi-finished products, meat and bone meal, sperm, embryos, technical fat, intestinal raw materials and other products and feeds of animal origin from ruminants. In order to prevent mad cow disease infection, it is necessary to inform veterinary clinics in a timely manner.

What is mad cow disease?

Bovine spongiform encephalopathy (BSE), or mad cow disease, is a slowly developing infectious prion transmissible disease of adult cattle, characterized by a long, up to 2.5-8 years, incubation period and manifested by damage to the central nervous system with 100% mortality.

Historical reference.

Spongiform encephalopathy was first reported in 1985-1986 in the UK under the name “mad cow disease”. In the next 10 years, BSE spread to other countries: France, Portugal, Switzerland, Germany, the Netherlands, Italy, Denmark, Slovakia, Finland, etc.

scrapie cattle (scrapie) – a similar agent (causative agent of sheep scrapie), found in meat and bone meal, which was included in the diet of cattle. In Russia, the disease has not been registered.

Economic damage.

BSE caused enormous economic damage to European countries, due to the fact that about 4 million heads of cattle were destroyed. The UK alone suffered an economic loss of £7 billion.

Epizootological data.

Under natural conditions, cattle are susceptible to BSE, especially at 4 years of age. The source of the causative agent of infection are sick and animals in the incubation period. The factors of transmission of the infectious agent are the products of slaughter of sheep with scrapie, and cattle with EH.

Course and symptoms of the disease.

The incubation period is from 2.5 to 8 years, in some cases it can be extended up to 25-30 years. The course of the disease is progressive, without remissions. The disease proceeds without an increase in body temperature of the animal, with continued appetite. Despite a normal appetite, cows have reduced milk production.

The clinical manifestation of the disease is characterized by signs of damage to the central nervous system.

Three types of nervous phenomena are detected during GE.

The first type of nervous phenomena is accompanied by the development in animals of a feeling of fear, nervousness, aggressiveness, gnashing of teeth, restlessness, timidity. The above symptoms occur in 98% of sick animals.
The second type of nervous phenomena is characterized by the presence of movement disorders in sick animals: trotting movements, “raking in the front limbs”, “lowering” of the hind legs, raised tail
In the third type of nervous phenomena, there is a violation of sensitivity, when in sick animals we note hyperesthesia with noise, touch and light. The duration of the disease is from several weeks to 12 months or more. The disease always ends in the death of the animal.

Pathological changes.

At autopsy of dead animals, characteristic pathoanatomical changes are either absent or mild.

Diagnosis.

Send to the laboratory for diagnostic tests:

– bovine brain after testing for rabies and other viral infections after the diagnosis was not confirmed;

– the brain of cattle from meat processing plants (0. 01% of slaughtered animals older than 3 years).

Pathological material (brain) is taken from animals with clinical signs of damage to the central nervous system). In this case, the brain for research must be taken from animals immediately after their slaughter or death.

Specific prophylaxis.

BSE does not produce either cellular or humoral immunity, so no vaccine has been developed in the world to date.

Treatment.

Treatment is ineffective, the prognosis for the disease is unfavorable.

Prevention.

The basis of prevention for prosperous countries is: preventing the importation of pedigree cattle, meat, canned food, by-products and semi-finished products, meat and bone meal, semen, embryos, technical fat, intestinal raw materials and other products and feeds of animal origin from ruminants; careful control over purchases of breeding stock and biological tissues, especially from disadvantaged countries; prohibition of feeding ruminants with meat-and-bone and bone meal from cattle and sheep.

If BSE is suspected, contact a veterinary clinic.

In order to prevent bovine spongiform encephalopathy, owners of susceptible animals must strictly comply with the requirements provided for in paragraph 7 of the Veterinary Rules for the implementation of preventive, diagnostic, restrictive and other measures, the establishment and lifting of quarantine and other restrictions aimed at preventing the spread and eliminating foci of large spongiform encephalopathy approved (hereinafter referred to as the Veterinary Rules), including paragraphs 6 and 7 of clause 7 of the Veterinary Rules regarding the incineration of waste from the slaughter of susceptible animals and the prohibition of feeding animals meat and bone, bone meal, protein briquettes, as well as other feed and feed additives for animals containing ruminant proteins in their composition.

“Mad cow disease” is gaining momentum – RBC

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