Subacute Sclerosing Panencephalitis (SSPE) is a rare, progressive, and fatal inflammatory disease of the brain characterized by seizures, cognitive decline, and motor function loss. It is caused by a persistent infection with the measles virus, even in individuals who had an uncomplicated acute measles infection earlier in life. The infection results in widespread degeneration and scarring (sclerosis) of the brain's gray matter.

The subacute phase of SSPE typically lasts for several months to a couple of years, during which patients experience a decline in cognitive abilities, behavioral changes, myoclonic jerks (involuntary muscle spasms), and visual disturbances. As the disease progresses, it leads to severe neurological impairment, coma, and eventually death.

SSPE is preventable through early childhood measles vaccination, which significantly reduces the risk of developing this fatal condition later in life.

Subacute sclerosing panencephalitis (SSPE) is not caused by a virus, but rather it is a slow, progressive, and fatal inflammatory disease of the central nervous system that is caused by a persistent infection with the measles virus. Therefore, there isn't a specific "SSPE virus," but rather SSPE is a complication of a measles virus infection.

In most cases, measles causes an acute infection that lasts for about 1-2 weeks and then resolves. However, in rare cases, the measles virus can persist in the body, particularly in immunocompromised individuals, and cause a progressive neurological disorder known as SSPE. The disease typically develops several years after the initial measles infection, and it is characterized by behavioral changes, intellectual deterioration, myoclonus (involuntary muscle jerks), seizures, and eventually coma and death.

It's important to note that vaccination against measles is highly effective in preventing both the acute infection and the development of SSPE.

Measles virus is a single-stranded, negative-sense RNA virus belonging to the genus Morbillivirus in the family Paramyxoviridae. It is the causative agent of measles, a highly contagious infectious disease characterized by fever, cough, runny nose, and a red, blotchy rash. The virus primarily infects the respiratory tract and then spreads throughout the body via the bloodstream.

The genome of the measles virus is approximately 16 kilobases in length and encodes for eight proteins: nucleocapsid (N), phosphoprotein (P), matrix protein (M), fusion protein (F), hemagglutinin (H), large protein (L), and two non-structural proteins, V and C. The H protein is responsible for binding to the host cell receptor CD150 (SLAM) and mediating viral entry, while the F protein facilitates fusion of the viral and host cell membranes.

Measles virus is transmitted through respiratory droplets and direct contact with infected individuals. The virus can remain airborne for up to two hours in a closed space, making it highly contagious. Measles is preventable through vaccination, which has led to significant reductions in the incidence of the disease worldwide.

Measles, also known as rubeola, is a highly infectious viral disease that primarily affects the respiratory system. It is caused by the measles virus, which belongs to the family Paramyxoviridae and the genus Morbillivirus. The virus is transmitted through direct contact with infected individuals or through airborne droplets released during coughing and sneezing.

The classic symptoms of measles include:

1. Fever: A high fever (often greater than 104°F or 40°C) usually appears before the onset of the rash, lasting for about 4-7 days.
2. Cough: A persistent cough is common and may become severe.
3. Runny nose: A runny or blocked nose is often present during the early stages of the illness.
4. Red eyes (conjunctivitis): Inflammation of the conjunctiva, the mucous membrane that covers the inner surface of the eyelids and the white part of the eye, can cause redness and irritation.
5. Koplik's spots: These are small, irregular, bluish-white spots with a red base that appear on the inside lining of the cheeks, usually 1-2 days before the rash appears. They are considered pathognomonic for measles, meaning their presence confirms the diagnosis.
6. Rash: The characteristic measles rash typically starts on the face and behind the ears, then spreads downward to the neck, trunk, arms, and legs. It consists of flat red spots that may merge together, forming irregular patches. The rash usually lasts for 5-7 days before fading.

Complications from measles can be severe and include pneumonia, encephalitis (inflammation of the brain), and ear infections. In rare cases, measles can lead to serious long-term complications or even death, particularly in young children, pregnant women, and individuals with weakened immune systems.

Vaccination is an effective way to prevent measles. The measles vaccine is typically administered as part of the Measles, Mumps, and Rubella (MMR) vaccine, which provides immunity against all three diseases.

Slow virus diseases, also known as persistent viral infections or chronic viral infections, are characterized by a lengthy incubation period and a slow progression of symptoms. These viruses can remain dormant in the body for extended periods, sometimes even years, before they start causing damage to cells and tissues.

The term "slow virus" is somewhat misleading because it does not necessarily mean that the virus itself is slow-replicating. Instead, it refers to the fact that the disease progression is slow and can take a long time to manifest symptoms. The immune system may have difficulty recognizing and eliminating these viruses, allowing them to persist in the body and cause ongoing damage over time.

Examples of slow virus diseases include:

1. Progressive multifocal leukoencephalopathy (PML): A rare and serious brain infection caused by the JC virus that primarily affects people with weakened immune systems, such as those with HIV/AIDS or those taking immunosuppressive drugs.
2. Subacute sclerosing panencephalitis (SSPE): A progressive neurological disorder caused by a measles virus infection that has become persistent in the brain. It primarily affects children and young adults who had measles during their early childhood.
3. Kuru: A rare, fatal degenerative neurological disorder that was once prevalent among the Fore people of Papua New Guinea. It is caused by an infectious protein called a prion, which can be transmitted through cannibalistic practices.
4. Creutzfeldt-Jakob disease (CJD): A rare and fatal brain disorder caused by prions. There are several types of CJD, including sporadic, hereditary, and acquired forms. The acquired form is a slow virus disease that can be transmitted through contaminated surgical instruments or dura mater grafts.
5. Human T-lymphotropic virus type 1 (HTLV-1) infection: A retrovirus that can cause adult T-cell leukemia/lymphoma and a progressive neurological disorder called HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP).
6. Progressive multifocal leukoencephalopathy (PML): A rare, often fatal demyelinating disease of the central nervous system caused by the JC polyomavirus. It primarily affects individuals with weakened immune systems, such as those with HIV/AIDS or those receiving immunosuppressive therapy for organ transplantation.

Inclusion bodies, viral are typically described as intracellular inclusions that appear as a result of viral infections. These inclusion bodies consist of aggregates of virus-specific proteins, viral particles, or both, which accumulate inside the host cell's cytoplasm or nucleus during the replication cycle of certain viruses.

The presence of inclusion bodies can sometimes be observed through histological or cytological examination using various staining techniques. Different types of viruses may exhibit distinct morphologies and locations of these inclusion bodies, which can aid in the identification and diagnosis of specific viral infections. However, it is important to note that not all viral infections result in the formation of inclusion bodies, and their presence does not necessarily indicate active viral replication or infection.

Skin manifestations refer to visible changes on the skin that can indicate an underlying medical condition or disease process. These changes can include rashes, lesions, discoloration, eruptions, blisters, hives, and other abnormalities. The appearance, distribution, and pattern of these manifestations can provide important clues for healthcare professionals to diagnose and manage the underlying condition.

Skin manifestations can be caused by a wide range of factors, including infections, inflammatory conditions, allergic reactions, genetic disorders, autoimmune diseases, and cancer. In some cases, skin manifestations may be the primary symptom of a medical condition, while in other cases, they may be a secondary effect of medication or treatment.

It is important to note that while skin manifestations can provide valuable diagnostic information, they should always be evaluated in the context of the patient's overall medical history and presentation. A thorough physical examination and appropriate diagnostic tests are often necessary to confirm a diagnosis and develop an effective treatment plan.

Morbillivirus is a genus of viruses in the family Paramyxoviridae, order Mononegavirales. It includes several important human and animal pathogens that cause diseases with significant morbidity and mortality. The most well-known member of this genus is Measles virus (MV), which causes measles in humans, a highly contagious disease characterized by fever, rash, cough, and conjunctivitis.

Other important Morbilliviruses include:

* Rinderpest virus (RPV): This virus caused rinderpest, a severe disease in cattle and other cloven-hoofed animals, which was eradicated in 2011 through a global vaccination campaign.
* Canine Distemper Virus (CDV): A pathogen that affects dogs, wild canids, and several other mammalian species, causing a systemic disease with respiratory, gastrointestinal, and neurological symptoms.
* Phocine Distemper Virus (PDV) and Porpoise Morbillivirus (PMV): These viruses affect marine mammals, such as seals and porpoises, causing mass mortality events in their populations.

Morbilliviruses are enveloped, negative-sense, single-stranded RNA viruses with a genome size of approximately 15-16 kilobases. They have a pleomorphic shape and can vary in diameter from 150 to 750 nanometers. The viral envelope contains two glycoproteins: the hemagglutinin (H) protein, which mediates attachment to host cells, and the fusion (F) protein, which facilitates membrane fusion and viral entry.

Transmission of Morbilliviruses typically occurs through respiratory droplets or direct contact with infected individuals or animals. The viruses can cause acute infections with high fatality rates, particularly in naïve populations that lack immunity due to insufficient vaccination coverage or the absence of previous exposure.

In summary, Morbillivirus is a genus of viruses in the family Paramyxoviridae that includes several important human and animal pathogens causing acute respiratory infections with high fatality rates. Transmission occurs through respiratory droplets or direct contact, and vaccination plays a crucial role in preventing outbreaks and controlling disease spread.

Antibodies, viral are proteins produced by the immune system in response to an infection with a virus. These antibodies are capable of recognizing and binding to specific antigens on the surface of the virus, which helps to neutralize or destroy the virus and prevent its replication. Once produced, these antibodies can provide immunity against future infections with the same virus.

Viral antibodies are typically composed of four polypeptide chains - two heavy chains and two light chains - that are held together by disulfide bonds. The binding site for the antigen is located at the tip of the Y-shaped structure, formed by the variable regions of the heavy and light chains.

There are five classes of antibodies in humans: IgA, IgD, IgE, IgG, and IgM. Each class has a different function and is distributed differently throughout the body. For example, IgG is the most common type of antibody found in the bloodstream and provides long-term immunity against viruses, while IgA is found primarily in mucous membranes and helps to protect against respiratory and gastrointestinal infections.

In addition to their role in the immune response, viral antibodies can also be used as diagnostic tools to detect the presence of a specific virus in a patient's blood or other bodily fluids.

Sclerosing cholangitis is a chronic progressive disease characterized by inflammation and scarring (fibrosis) of the bile ducts, leading to their narrowing or obstruction. This results in impaired bile flow from the liver to the small intestine, which can cause damage to the liver cells and eventually result in cirrhosis and liver failure.

The condition often affects both the intrahepatic (within the liver) and extrahepatic (outside the liver) bile ducts. The exact cause of sclerosing cholangitis is not known, but it is believed to involve an autoimmune response, genetic predisposition, and environmental factors.

Symptoms of sclerosing cholangitis may include jaundice (yellowing of the skin and eyes), itching, abdominal pain, fatigue, weight loss, dark urine, and light-colored stools. The diagnosis is typically made through imaging tests such as magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP), which can visualize the bile ducts and detect any abnormalities.

Treatment for sclerosing cholangitis is aimed at managing symptoms, preventing complications, and slowing down the progression of the disease. This may include medications to relieve itching, antibiotics to treat infections, and drugs to reduce inflammation and improve bile flow. In severe cases, a liver transplant may be necessary.

Viral matrix proteins are structural proteins that play a crucial role in the morphogenesis and life cycle of many viruses. They are often located between the viral envelope and the viral genome, serving as a scaffold for virus assembly and budding. These proteins also interact with other viral components, such as the viral genome, capsid proteins, and envelope proteins, to form an infectious virion. Additionally, matrix proteins can have regulatory functions, influencing viral transcription, replication, and host cell responses. The specific functions of viral matrix proteins vary among different virus families.

Immunoglobulin G (IgG) is a type of antibody, which is a protective protein produced by the immune system in response to foreign substances like bacteria or viruses. IgG is the most abundant type of antibody in human blood, making up about 75-80% of all antibodies. It is found in all body fluids and plays a crucial role in fighting infections caused by bacteria, viruses, and toxins.

IgG has several important functions:

1. Neutralization: IgG can bind to the surface of bacteria or viruses, preventing them from attaching to and infecting human cells.
2. Opsonization: IgG coats the surface of pathogens, making them more recognizable and easier for immune cells like neutrophils and macrophages to phagocytose (engulf and destroy) them.
3. Complement activation: IgG can activate the complement system, a group of proteins that work together to help eliminate pathogens from the body. Activation of the complement system leads to the formation of the membrane attack complex, which creates holes in the cell membranes of bacteria, leading to their lysis (destruction).
4. Antibody-dependent cellular cytotoxicity (ADCC): IgG can bind to immune cells like natural killer (NK) cells and trigger them to release substances that cause target cells (such as virus-infected or cancerous cells) to undergo apoptosis (programmed cell death).
5. Immune complex formation: IgG can form immune complexes with antigens, which can then be removed from the body through various mechanisms, such as phagocytosis by immune cells or excretion in urine.

IgG is a critical component of adaptive immunity and provides long-lasting protection against reinfection with many pathogens. It has four subclasses (IgG1, IgG2, IgG3, and IgG4) that differ in their structure, function, and distribution in the body.

A measles vaccine is a biological preparation that induces immunity against the measles virus. It contains an attenuated (weakened) strain of the measles virus, which stimulates the immune system to produce antibodies that protect against future infection with the wild-type (disease-causing) virus. Measles vaccines are typically administered in combination with vaccines against mumps and rubella (German measles), forming the MMR vaccine.

The measles vaccine is highly effective, with one or two doses providing immunity in over 95% of people who receive it. It is usually given to children as part of routine childhood immunization programs, with the first dose administered at 12-15 months of age and the second dose at 4-6 years of age.

Measles vaccination has led to a dramatic reduction in the incidence of measles worldwide and is considered one of the greatest public health achievements of the past century. However, despite widespread availability of the vaccine, measles remains a significant cause of morbidity and mortality in some parts of the world, particularly in areas with low vaccination coverage or where access to healthcare is limited.

Encephalitis is defined as inflammation of the brain parenchyma, which is often caused by viral infections but can also be due to bacterial, fungal, or parasitic infections, autoimmune disorders, or exposure to toxins. The infection or inflammation can cause various symptoms such as headache, fever, confusion, seizures, and altered consciousness, ranging from mild symptoms to severe cases that can lead to brain damage, long-term disabilities, or even death.

The diagnosis of encephalitis typically involves a combination of clinical evaluation, imaging studies (such as MRI or CT scans), and laboratory tests (such as cerebrospinal fluid analysis). Treatment may include antiviral medications, corticosteroids, immunoglobulins, and supportive care to manage symptoms and prevent complications.

Canine distemper virus (CDV) is a single-stranded RNA virus that belongs to the family Paramyxoviridae and causes a contagious and serious disease in dogs and other animals. The virus primarily affects the respiratory, gastrointestinal, and central nervous systems of infected animals.

The symptoms of canine distemper can vary widely depending on the age and immune status of the animal, as well as the strain of the virus. Initial signs may include fever, lethargy, loss of appetite, and discharge from the eyes and nose. As the disease progresses, affected animals may develop vomiting, diarrhea, pneumonia, and neurological symptoms such as seizures, muscle twitching, and paralysis.

Canine distemper is highly contagious and can be spread through direct contact with infected animals or their respiratory secretions. The virus can also be transmitted through contaminated objects such as food bowls, water dishes, and bedding.

Prevention of canine distemper is achieved through vaccination, which is recommended for all dogs as a core vaccine. It is important to keep dogs up-to-date on their vaccinations and to avoid contact with unfamiliar or unvaccinated animals. There is no specific treatment for canine distemper, and therapy is generally supportive, focusing on managing symptoms and preventing complications.

The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:

1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.

The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.

Multiple Sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS), which includes the brain, spinal cord, and optic nerves. In MS, the immune system mistakenly attacks the protective covering of nerve fibers, called myelin, leading to damage and scarring (sclerosis). This results in disrupted communication between the brain and the rest of the body, causing a variety of neurological symptoms that can vary widely from person to person.

The term "multiple" refers to the numerous areas of scarring that occur throughout the CNS in this condition. The progression, severity, and specific symptoms of MS are unpredictable and may include vision problems, muscle weakness, numbness or tingling, difficulty with balance and coordination, cognitive impairment, and mood changes. There is currently no cure for MS, but various treatments can help manage symptoms, modify the course of the disease, and improve quality of life for those affected.

Hemagglutination inhibition (HI) tests are a type of serological assay used in medical laboratories to detect and measure the amount of antibodies present in a patient's serum. These tests are commonly used to diagnose viral infections, such as influenza or HIV, by identifying the presence of antibodies that bind to specific viral antigens and prevent hemagglutination (the agglutination or clumping together of red blood cells).

In an HI test, a small amount of the patient's serum is mixed with a known quantity of the viral antigen, which has been treated to attach to red blood cells. If the patient's serum contains antibodies that bind to the viral antigen, they will prevent the antigen from attaching to the red blood cells and inhibit hemagglutination. The degree of hemagglutination inhibition can be measured and used to estimate the amount of antibody present in the patient's serum.

HI tests are relatively simple and inexpensive to perform, but they have some limitations. For example, they may not detect early-stage infections before the body has had a chance to produce antibodies, and they may not be able to distinguish between different strains of the same virus. Nonetheless, HI tests remain an important tool for diagnosing viral infections and monitoring immune responses to vaccination or infection.

CD46, also known as membrane cofactor protein (MCP), is a regulatory protein that plays a role in the immune system and helps to protect cells from complement activation. It is found on the surface of many different types of cells in the body, including cells of the immune system such as T cells and B cells, as well as cells of various other tissues such as epithelial cells and endothelial cells.

As an antigen, CD46 is a molecule that can be recognized by the immune system and stimulate an immune response. It is a type I transmembrane protein that consists of four distinct domains: two short cytoplasmic domains, a transmembrane domain, and a large extracellular domain. The extracellular domain contains several binding sites for complement proteins, which helps to regulate the activation of the complement system and prevent it from damaging host cells.

CD46 has been shown to play a role in protecting cells from complement-mediated damage, modulating immune responses, and promoting the survival and proliferation of certain types of immune cells. It is also thought to be involved in the development of some autoimmune diseases and may be a target for immunotherapy in the treatment of cancer.

Nucleocapsid proteins are structural proteins that are associated with the viral genome in many viruses. They play a crucial role in the formation and stability of the viral particle, also known as the virion. In particular, nucleocapsid proteins bind to the viral RNA or DNA genome and help to protect it from degradation by host cell enzymes. They also participate in the assembly and disassembly of the virion during the viral replication cycle.

In some viruses, such as coronaviruses, the nucleocapsid protein is also involved in regulating the transcription and replication of the viral genome. The nucleocapsid protein of SARS-CoV-2, for example, has been shown to interact with host cell proteins that are involved in the regulation of gene expression, which may contribute to the virus's ability to manipulate the host cell environment and evade the immune response.

Overall, nucleocapsid proteins are important components of many viruses and are often targeted by antiviral therapies due to their essential role in the viral replication cycle.

An antigen is any substance that can stimulate an immune response, particularly the production of antibodies. Viral antigens are antigens that are found on or produced by viruses. They can be proteins, glycoproteins, or carbohydrates present on the surface or inside the viral particle.

Viral antigens play a crucial role in the immune system's recognition and response to viral infections. When a virus infects a host cell, it may display its antigens on the surface of the infected cell. This allows the immune system to recognize and target the infected cells for destruction, thereby limiting the spread of the virus.

Viral antigens are also important targets for vaccines. Vaccines typically work by introducing a harmless form of a viral antigen to the body, which then stimulates the production of antibodies and memory T-cells that can recognize and respond quickly and effectively to future infections with the actual virus.

It's worth noting that different types of viruses have different antigens, and these antigens can vary between strains of the same virus. This is why there are often different vaccines available for different viral diseases, and why flu vaccines need to be updated every year to account for changes in the circulating influenza virus strains.

A Cytopathic Effect (CPE) is a visible change in the cell or group of cells due to infection by a pathogen, such as a virus. When the cytopathic effect is caused specifically by a viral infection, it is referred to as a "Viral Cytopathic Effect" (VCPE).

The VCPE can include various changes in the cell's morphology, size, and structure, such as rounding, shrinkage, multinucleation, inclusion bodies, and formation of syncytia (multinucleated giant cells). These changes are often used to identify and characterize viruses in laboratory settings.

The VCPE is typically observed under a microscope after the virus has infected cell cultures, and it can help researchers determine the type of virus, the degree of infection, and the effectiveness of antiviral treatments. The severity and timing of the VCPE can vary depending on the specific virus and the type of cells that are infected.

Haplorhini is a term used in the field of primatology and physical anthropology to refer to a parvorder of simian primates, which includes humans, apes (both great and small), and Old World monkeys. The name "Haplorhini" comes from the Greek words "haploos," meaning single or simple, and "rhinos," meaning nose.

The defining characteristic of Haplorhini is the presence of a simple, dry nose, as opposed to the wet, fleshy noses found in other primates, such as New World monkeys and strepsirrhines (which include lemurs and lorises). The nostrils of haplorhines are located close together at the tip of the snout, and they lack the rhinarium or "wet nose" that is present in other primates.

Haplorhini is further divided into two infraorders: Simiiformes (which includes apes and Old World monkeys) and Tarsioidea (which includes tarsiers). These groups are distinguished by various anatomical and behavioral differences, such as the presence or absence of a tail, the structure of the hand and foot, and the degree of sociality.

Overall, Haplorhini is a group of primates that share a number of distinctive features related to their sensory systems, locomotion, and social behavior. Understanding the evolutionary history and diversity of this group is an important area of research in anthropology, biology, and psychology.

Virus cultivation, also known as virus isolation or viral culture, is a laboratory method used to propagate and detect viruses by introducing them to host cells and allowing them to replicate. This process helps in identifying the specific virus causing an infection and studying its characteristics, such as morphology, growth pattern, and sensitivity to antiviral agents.

The steps involved in virus cultivation typically include:

1. Collection of a clinical sample (e.g., throat swab, blood, sputum) from the patient.
2. Preparation of the sample by centrifugation or filtration to remove cellular debris and other contaminants.
3. Inoculation of the prepared sample into susceptible host cells, which can be primary cell cultures, continuous cell lines, or embryonated eggs, depending on the type of virus.
4. Incubation of the inoculated cells under appropriate conditions to allow viral replication.
5. Observation for cytopathic effects (CPE), which are changes in the host cells caused by viral replication, such as cell rounding, shrinkage, or lysis.
6. Confirmation of viral presence through additional tests, like immunofluorescence assays, polymerase chain reaction (PCR), or electron microscopy.

Virus cultivation is a valuable tool in diagnostic virology, vaccine development, and research on viral pathogenesis and host-virus interactions. However, it requires specialized equipment, trained personnel, and biosafety measures due to the potential infectivity of the viruses being cultured.

Electroencephalography (EEG) is a medical procedure that records electrical activity in the brain. It uses small, metal discs called electrodes, which are attached to the scalp with paste or a specialized cap. These electrodes detect tiny electrical charges that result from the activity of brain cells, and the EEG machine then amplifies and records these signals.

EEG is used to diagnose various conditions related to the brain, such as seizures, sleep disorders, head injuries, infections, and degenerative diseases like Alzheimer's or Parkinson's. It can also be used during surgery to monitor brain activity and ensure that surgical procedures do not interfere with vital functions.

EEG is a safe and non-invasive procedure that typically takes about 30 minutes to an hour to complete, although longer recordings may be necessary in some cases. Patients are usually asked to relax and remain still during the test, as movement can affect the quality of the recording.

Viral proteins are the proteins that are encoded by the viral genome and are essential for the viral life cycle. These proteins can be structural or non-structural and play various roles in the virus's replication, infection, and assembly process. Structural proteins make up the physical structure of the virus, including the capsid (the protein shell that surrounds the viral genome) and any envelope proteins (that may be present on enveloped viruses). Non-structural proteins are involved in the replication of the viral genome and modulation of the host cell environment to favor viral replication. Overall, a thorough understanding of viral proteins is crucial for developing antiviral therapies and vaccines.