Mucca Pazza: What is it? Causes, Symptoms, Diagnosis, Therapy and Relations with the Human Being of A.Griguolo

Generality

The mad cow is a neurodegenerative disease typical of cattle, always fatal, which creates on the encephalon of holes, such that this organ takes on the appearance of a sponge.

As a transmissible condition, mad cow seems to be due to a modified form of a normal protein expressed in almost all mammals, whose name is prion.

After a completely asymptomatic incubation period of 3 to 5 years, the mad cow begins to show herself, with symptoms such as: tremors, myoclonus, balance and motor coordination problems, abnormal gait, difficulty getting up, changes in behavior and hyper-reactivity to stimuli.

The mad cow is a disease for which there is no cure, except for some symptomatic treatment.

The mad cow is a condition of considerable interest for human beings, since, in the mid-1990s, some people living in the United Kingdom developed an equivalent neurological disease, after consuming meat from sick cattle.

Brief reference to Encephalopathies

Encephalopathies represent a group of non-inflammatory neurological diseases, characterized by a structural alteration of the brain that affects the functions of the latter and in general the so-called mental state .

Congenital or acquired, an encephalopathy can be a permanent and incurable condition ( permanent encephalopathy ) or a condition that has a more or less considerable margin of healing ( temporary encephalopathy ).

To distinguish one encephalopathy from another are: the causes (to which the specific name of the disease is usually given), the symptoms, the possible complications, the expected treatment and the prognosis.

In general, those suffering from an encephalopathy develop numerous disorders, including for example memory impairment (especially amnesia), depression, personality changes, inability to solve simple problems of daily life, lethargy, myoclonus and tremor.

What is the Mad Cow?

The mad cow, also known as bovine spongiform encephalopathy, BSE or mad cow disease, is a progressive neurological disease typical of cattle, characterized by a permanent degeneration of the brain so that the latter assumes the appearance of a sponge (from which the term "spongiform") and loses its normal functions.

From the always fatal outcome, the mad cow is a condition transmissible to animals of the same species and to animals of different species (including the human being), when a healthy subject ingests some tissue of a sick subject.

To understand: a brief review of the meaning of some key terms

• "Spongiform": indicates that the brain develops pores on the cerebral cortex, such as to be similar to a sponge.
• "Bovine": refers to the fact that it affects cattle, especially cows.
• "Progressive neurological disease": indicates a suffering of the nervous system (neurological disease) which worsens over time (progressive).
• "Neurodegenerative disease": refers to a disease that involves a degeneration of the nervous system.

The Mad Cow as a Transmissible Disease

Due to its transmissibility, the mad cow is included in the list of so-called transmissible spongiform encephalopathies (or TSEs ); Transmissible spongiform encephalopathies are spongiform encephalopathies that a healthy subject can develop if he ingests tissues from an affected subject.

Like the mad cow are transmissible spongiform encephalopathies: kuru, fatal familial insomnia, Gerstmann-Sträussler-Scheinker syndrome, Creutzfeldt-Jakob disease, new variant of Creutzfeldt-Jakob disease, scrapie, encephalopathy feline spongiform, spongiform encephalopathy of the mink, encephalopathy of exotic ungulates and chronic wasting disease of the deer .

Mad Cow and Human Being: the connection

The mad cow represents a topic of extreme interest for the human being, since - as will be seen a little later - in the mid-90s of the 900, in correspondence with a BSE epidemic that took place in the United Kingdom, a non-negligible percentage of people fell ill with a neurological disease very similar to Creutzfeldt-Jakob disease, after having consumed meat belonging to sick cattle.

This neurological disease very similar to Creutzfeldt-Jakob disease is the aforementioned new variant of Creutzfeldt-Jakob disease.

The new variant of Creutzfeldt-Jakob disease can be considered the human equivalent of mad cow disease .

A bit of History of the Mad Cow

The first identified cases of mad cow date back to 1986 ; the place of discovery was a cattle farm in the United Kingdom.

From that moment on, just in the United Kingdom, a sort of BSE epidemic began, reaching its peak in 1993 (a period in which, according to the statistics of the time, the beauty of 1000 new cases of sick cattle were counted at week) and was slowly exhausted, thanks to a series of government measures, in the following years (in 2015 the cases of mad cow registered were only 2).

According to the experts in the sector, the mad cow epidemic was used to feed animal-based flours in UK cattle farms, in which there were meat and minced bones from cattle suffering from a sporadic form of BSE (remember that mad cow is a transmissible disease).

Beyond the impressive numbers reached, the mad cow epidemic occurred in the United Kingdom had a strong echo not only in Europe but also worldwide, for another reason: a few years after the first cases of BSE, a percentage not negligible number of English citizens began to develop, as a result of the consumption of meat of bovines sick of bovine spongiform encephalopathy, a new neurological disease, very similar to the Creutzfeldt-Jakob disease (ie the new variant of Creutzfeldt-Jakob disease).

According to statistics of June 2014, the sick people of the new variant of Creutzfeldt-Jakob disease, as a result of the effects of the BSE epidemic in the United Kingdom starting from the late 1980s, were 177 .

Causes

The precise causes of the mad cow are not yet completely clear.

According to most experts, however, the appearance of the neurological disease in question would have as its protagonist a modified form of a protein normally present in cattle, whose name is prion or cellular prion protein .

The Prione and the Mad Cow

WHAT IS PRION?

Normally present in numerous species of Mammals (including human beings), Reptiles, Birds, Amphibians and Pisces, the prion is, in its healthy variant, a glycoprotein with a high probability of signal transduction or cell adhesion (on the role precise there are still doubts).

PRIONE AS A CAUSE OF MUCH COW

The idea that the prion is involved in the onset of the mad cow is the result of two equally important observations:

• First observation: in cattle with BSE there are modified forms of the prion protein. By modified forms of the prion protein, it is understood that the prion has an anomalous conformation, different from the normal.
• Second observation: in the modified variant, the prion loses its glycoprotein function and acquires such properties, which make it harmful to the encephalon and nervous tissue in general and capable of transforming normal prions (ie in the healthy variant) into prions modified .

In light of these two important observations, the experts compared the prion to a sort of infectious agent (ie they equated it to a virus or a bacterium), assigning them also the alternative names of " unconventional infectious agent " and " infectious particle only protein ".

The modified form of the prion is responsible for a chain reaction with devastating effects ; its manifestation, in fact, involves the progressive modification of normal prions, present in the affected subject, and the formation of protein aggregates which, after having affected the encephalon in several points, cause the death of the nervous tissue, creating real holes in it (the spongiform aspect that characterizes the brain of BSE affected cattle is the result of the creation of these holes).

OTHER CHARACTERISTICS OF MODIFIED PRION

Scientific studies on the prion have shown that:

• The prion is also smaller than the viruses (which are the smallest infectious agents);
• The prion is incredibly resistant to the most classic procedures used to eliminate viruses, bacteria, fungi or other known microorganisms. This explains why the cooking of the meat belonging to the cattle suffering from mad cow does not destroy the modified prion present.

PRIONE AND OTHER DISEASES

According to those who see the cause of the mad cow in the prion, the same prion would also be implicated in all known transmissible spongiform encephalopathies; in other words, the appearance of Creutzfeldt-Jakob disease, the new variant of Creutzfeldt-Jakob disease, the kuru, the Gerstmann-Sträussler-Scheinker syndrome, the feline spongiform encephalopathy, the mink spongiform encephalopathy etc.

Obviously, the idea that the prion is also involved in other known transmissible spongiform encephalopathies derives from scientific observations similar to those reported for mad cow disease (presence of modified prions in sick animals and modified prions capable of attacking the brain, causing damage to it) .

In pathology, the diseases that doctors believe are related to the modified prion (such as transmissible spongiform encephalopathies) are also called prion diseases .

Incubation Times

The mad cow has long incubation times ; in fact, the bovine that comes into contact with the causative agent of the disease - the modified prion, if this were the cause of the condition - develops the disease within the next 3-5 years .

Did you know that ...

When the human being contracts the human equivalent of the mad cow by ingestion of contaminated beef, it could manifest the neurological disease even more than 10 years after the aforementioned ingestion event .

According to the most recent studies, the average incubation period of the human mad cow equivalent would be 13 years.

Transmission of Mad Cow to the Human Being

The transmission of mad cow to human being can take place only by ingestion of meat belonging to a BSE sick cattle.

The mad cow, therefore, is not like a cold or infectious infectious diseases, in which it is sufficient, for the transmission of the disease, even the simple proximity between the healthy subject and the sick subject.

Curiosity: does the milk of a cow affected by BSE transmit the disease?

Drinking milk from a BSE-affected cow or eating the latex produced with this milk is not enough to cause the human equivalent of mad cow disease .

Symptoms and Complications

Mad cow symptoms appear at the end of the incubation period, so they are not immediate at all.

Among the manifestations of BSE, there are typical disorders, such as:

• Poor balance and loss of motor coordination ( ataxia ),
• Tremors,
• Sudden muscle spasms ( myoclonus ),
• Abnormal and difficult pace,

• Difficulty getting up,
• Hyper-reactivity to certain stimuli e
• Changes in behavior (affected animals suddenly become aggressive or appear strangely nervous),

and less common or less specific disorders, such as:

• Tendency to continuous rubbing or licking,
• Weight loss,
• Continuous grinding of teeth,
• Recurring ear infections e
• Decrease in milk production.

The Mad Cow is a fatal disease

Mad cow disease is a fatal outcome .

Before death, in general, affected animals enter a coma .

Death from BSE occurs a few weeks or months after the onset of symptoms.

The Symptoms of Mad Cow in the Human Being

In humans, the equivalent of mad cow disease (ie the new variant of Creutzfeldt-Jakob disease) is responsible, at the end of the incubation period, for:

• Psychiatric symptoms, including depression, anxiety, withdrawal disorders, etc .;
• Progressive loss of motor coordination (ataxia);
• Sensory disorders;
• Dementia;
• Myoclonus (short and involuntary contraction of a muscle or a group of muscles).

The new variant of Creutzfeldt-Jakob disease is always fatal, exactly like the mad cow and the other known transmissible spongiform encephalopathies; normally, those who develop this disease die within 14 months .

Diagnosis

As long as the affected animal is alive, the presence of BSE is only conceivable on the basis of symptoms; for the definitive diagnosis of the mad cow, in fact, it is necessary to wait for the death of the sick bovine and the outcome of a post-mortem histopathological examination of the encephalic and nervous tissues .

Summing up, therefore, the mad cow is only a suspicious condition as long as the sick animal is alive, because for its definitive diagnosis a post-mortem laboratory examination of the nervous tissues is required.

It is possible to hypothesize the presence of Mucca Pazza during the Incubation

During the incubation period, the mad cow gives no sign of her presence .

Therefore, it is impossible to predict its future onset.

Examinations for the Diagnosis of the Human Equivalent of the Mad Cow

As is the case with mad cow disease, the new variant of Creutzfeldt-Jakob disease is a disease whose definitive diagnosis is not sufficient for the symptoms manifested by the sick person, but the results of the post-mortem histopathological examination on the nervous tissue of the 'brain.

Did you know that ...

Post-mortem histopathological examination of the brain's nervous tissue is the only diagnostic investigation that allows not only to identify the human equivalent of mad cow disease, but also to distinguish the latter from the human transmissible spongiform encephalopathy that most closely resembles it : Creutzfeldt-Jakob disease.

Therapy

Currently, there is no therapy capable of curing mad cow disease or even stopping its progression; this explains why the cattle that fall ill with BSE are inevitably destined for death.

Is there any symptomatic treatment?

Cattle affected by mad cow disease can count on some purely symptomatic treatments, which alleviate disorders such as tremors or sudden muscle spasms (myoclonus).

Human equivalent therapy of Mucca Pazza

The new variant of Creutzfeldt-Jakob disease is a disease for which there is no cure, except for some symptomatic treatment that alleviates the symptoms before the onset of death (eg the clonazepam and sodium valproate drugs against myoclonus).

Prognosis

The mad cow always presents a poor prognosis ; as reiterated on more than one occasion, in fact, this neurological disease always culminates with the death of the sick animal.

Prevention

Currently, at the center of any preventive plan against the mad cow is the prohibition of feeding cattle based on animal meal.