Mad cow disease other names. Mad Cow Disease: Understanding BSE, Prevention, and Impact on Public Health

21.08.202308.07.2023 by alexxlab

What is Bovine Spongiform Encephalopathy. How does mad cow disease spread. Can humans contract BSE. What measures are in place to prevent mad cow disease. How is BSE diagnosed in cattle. What are the symptoms of variant Creutzfeldt-Jakob disease. How has BSE affected the global beef industry.

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The Origins and Nature of Bovine Spongiform Encephalopathy

Bovine Spongiform Encephalopathy (BSE), commonly known as mad cow disease, is a fatal neurodegenerative disorder affecting cattle. This prion disease gained notoriety in the 1980s and 1990s due to its potential link to human health risks. But what exactly are prions, and how do they cause such devastating effects?

Prions are misfolded proteins that can trigger normal proteins in the brain to misfold as well, leading to brain damage and a range of neurological symptoms. In BSE, these prions primarily affect cattle, causing a spongy degeneration of the brain and spinal cord.

The Emergence of BSE

BSE was first identified in the United Kingdom in 1986, but its origins can be traced back to the practice of feeding cattle with meat and bone meal derived from other ruminants. This practice inadvertently led to the spread of prions among cattle populations, creating a cycle of infection that would have far-reaching consequences.

BSE is caused by prions, not bacteria or viruses
The disease has a long incubation period, often 4-6 years
Affected cattle show progressive neurological symptoms
There is no cure for BSE, and it is always fatal in affected animals

The First BSE Case in the United States: A Turning Point

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. This event marked a significant turning point in the country’s approach to beef safety and cattle management. But how did this case come to light, and what were its implications?

The infected animal was an adult Holstein cow from Washington State. Confirmation of the diagnosis came from an international reference laboratory in Weybridge, England, on December 25, 2003. Subsequent investigations revealed that the BSE-infected cow had been imported from Canada in August 2001, highlighting the interconnected nature of the North American cattle industry.

Immediate Response and Recall

Upon confirmation of the BSE case, swift action was taken to protect public health and maintain consumer confidence. The Food Safety and Inspection Service (FSIS) of the USDA issued a recall for all beef from cattle slaughtered on the same day and at the same plant as the infected cow. This precautionary measure aimed to eliminate any potential risk to consumers, even though the specific tissues known to carry the highest risk of BSE transmission had been removed during slaughter.

Identification of the infected cow through routine surveillance
Confirmation of diagnosis by international experts
Trace-back investigation to determine the cow’s origin
Recall of potentially affected beef products
Enhanced surveillance and testing protocols implemented

BSE Surveillance and Monitoring in the United States

Following the 2003 case, how did the United States enhance its BSE surveillance efforts? The USDA, in collaboration with various agencies, implemented a robust system to monitor and prevent the spread of BSE within the country’s cattle population.

The Centers for Disease Control and Prevention (CDC) plays a crucial role in monitoring trends and current incidence of Creutzfeldt-Jakob Disease (CJD), the human form of prion disease. This surveillance involves analyzing death certificate information and conducting follow-up reviews of clinical and neuropathology records for CJD decedents younger than 55 years of age.

The National Prion Disease Pathology Surveillance Center

In 1996-1997, the CDC, in collaboration with the American Association of Neuropathologists (AANP), established the National Prion Disease Pathology Surveillance Center at Case Western Reserve University in Cleveland, Ohio. This center provides free, state-of-the-art diagnostic services to U.S. physicians and helps monitor the possible occurrence of emerging forms of prion diseases, such as variant CJD (vCJD), in the United States.

Analysis of death certificate data for CJD cases
Follow-up reviews of young CJD decedents
Free diagnostic services for suspected prion diseases
Monitoring for emerging forms of prion diseases

Prevention Measures Against BSE Spread

How has the United States worked to prevent BSE from entering and spreading within its borders? The USDA has implemented severe restrictions 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 from all European countries.

One of the key prevention measures was the ban on the use of ruminant tissue in animal feed. This practice, which was believed to be the primary route of BSE transmission, was prohibited to break the cycle of infection among cattle populations.

Feed Bans and Surveillance

The feed ban, implemented by the Food and Drug Administration (FDA), prohibits the use of most mammalian protein in the manufacture of animal feed intended for ruminants. This measure aims to prevent the amplification of BSE within the cattle population should an infected animal enter the food chain.

Import restrictions on live ruminants and ruminant products
Ban on the use of most mammalian protein in ruminant feed
Enhanced surveillance of cattle populations
Strict guidelines for slaughter and processing of cattle

The Human Health Risk: Variant Creutzfeldt-Jakob Disease

While BSE primarily affects cattle, its potential link to human health has been a major concern. Variant Creutzfeldt-Jakob Disease (vCJD) is believed to be caused by consuming beef products contaminated with the BSE agent. But how significant is this risk, and what do we know about vCJD?

Strong evidence indicates that BSE has been transmitted to humans primarily in the United Kingdom, causing vCJD. However, the species barrier appears to provide some protection against widespread illness in humans. As of December 1, 2003, a total of 153 vCJD cases had been reported worldwide, with 143 of these occurring in the United Kingdom.

Symptoms and Diagnosis of vCJD

Variant CJD is a rare and fatal human neurodegenerative condition. Its symptoms can include psychiatric problems, behavioral changes, and painful sensations. As the disease progresses, neurological symptoms worsen, leading to loss of coordination, dementia, and ultimately death.

Early psychiatric symptoms such as depression and anxiety
Painful sensations and difficulty with coordination
Progressive neurological decline
Dementia in later stages
Fatal outcome with no known cure

Global Impact of BSE on the Beef Industry

The discovery of BSE cases in various countries has had far-reaching effects on the global beef industry. How have these outbreaks influenced international trade and consumer confidence in beef products?

The BSE crisis led to significant economic losses for beef producers and related industries. Many countries imposed bans on beef imports from affected nations, disrupting global trade patterns. Consumer fear and reduced beef consumption in some regions further compounded the economic impact.

Recovery and Rebuilding Trust

In the years following major BSE outbreaks, the beef industry has worked diligently to rebuild consumer trust and restore market stability. This has involved implementing stringent safety measures, enhancing transparency in production practices, and educating the public about the low risk of BSE transmission to humans when proper precautions are taken.

Implementation of comprehensive traceability systems
Enhanced testing and surveillance programs
Public education campaigns on beef safety
Gradual lifting of import bans as countries demonstrate BSE control
Development of alternative markets and products to diversify risk

Advancements in BSE Research and Diagnostic Techniques

Since the emergence of BSE, significant strides have been made in understanding prion diseases and developing more effective diagnostic tools. What are some of the key advancements in BSE research, and how have they improved our ability to detect and manage the disease?

Scientists have made progress in understanding the molecular mechanisms of prion propagation and the factors that influence susceptibility to BSE. This knowledge has led to the development of more sensitive and specific diagnostic tests, enabling earlier detection of the disease in cattle.

Innovations in BSE Testing

New diagnostic techniques, such as real-time quaking-induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA), have shown promise in detecting prions with high sensitivity. These methods could potentially allow for ante-mortem testing of cattle, which would be a significant advancement in BSE surveillance.

Development of more sensitive prion detection methods
Improved understanding of prion biology and disease mechanisms
Potential for ante-mortem testing in cattle
Advancements in genetic research related to BSE susceptibility

As research continues, our understanding of BSE and related prion diseases grows, leading to more effective prevention strategies and potentially opening avenues for treatment development. While the risk of BSE remains low in countries with strong prevention measures, ongoing vigilance and scientific inquiry are essential to maintain food safety and public health.

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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