Mt Simulation Examination 5

If a patient is still shedding poliovirus even after appearing to have recovered from the infection, it means that they can still transmit the virus to others. This is problematic because it can lead to the spread of the virus and potentially cause epidemics.

Plantar warts and flat warts are non-genital types of HPV. CIN 3 is caused by genital HPV of the high-risk type. Genital HPV types 6 and 11 can cause a rare condition known as recurrent respiratory papillomatosis, in which warts form on the larynx or other areas of the respiratory tract. HPV is acquired through oral-genital sexual contact, or when a mother with genital warts passes it to her baby during childbirth.

Enteroviruses are spread through fecal-oral contamination, which means that the virus is transmitted when someone ingests food or water that has been contaminated with fecal matter containing the virus. This can occur through poor hygiene practices, such as not washing hands properly after using the toilet. Once ingested, the virus can then infect the digestive system and cause illness.

Cell-mediated immunity is most responsible for fighting viral infections. This type of immunity involves the activation of T-cells, which directly attack and destroy infected cells. T-cells recognize viral antigens presented on the surface of infected cells and initiate an immune response to eliminate the virus. This response is particularly effective against intracellular pathogens like viruses. Humoral immunity, on the other hand, primarily deals with extracellular pathogens and involves the production of antibodies to neutralize viruses. Innate immunity provides immediate, non-specific defense mechanisms against a wide range of pathogens but may not be as effective against specific viral infections.

Cell cultures are used for the diagnosis of picornoviruses. This is because picornoviruses cannot be grown on chocolate agar plates, and reverse transcription PCR is often ineffective for their diagnosis. Cell cultures provide a suitable environment for the replication of picornoviruses, allowing for their detection and identification. Season, climate, and epidemics are irrelevant to the diagnosis process.

Hematogenous spread refers to the spread of the virus through the bloodstream. In the context of the given question, it suggests that the primary replication of the virus occurs before it spreads through the bloodstream. This means that the virus first replicates in a specific location, such as the respiratory tract or another site of initial infection, before entering the bloodstream and spreading to other parts of the body.

Type B influenza only undergoes antigenic drift and is not known to undergo antigenic shift. Antigenic drift refers to small genetic changes in the virus over time, leading to minor variations in the surface proteins. This allows the virus to evade the immune system and cause seasonal outbreaks. On the other hand, antigenic shift occurs when two different strains of influenza virus infect the same host and exchange genetic material, resulting in a completely new strain that can cause pandemics. Type B influenza primarily affects humans and seals, and its genetic changes are more gradual, making it less likely to cause major shifts in the virus.

Capillaries are tiny blood vessels that connect arterioles and venules. They are a site of entrance for arboviruses, which are transmitted by arthropods such as mosquitoes and ticks. Arboviruses enter the body through the bite of an infected arthropod and then travel through the bloodstream, infecting various organs and tissues. On the other hand, enteroviruses typically enter the body through ingestion, meaning they are ingested through contaminated food or water. Therefore, capillaries are a site of entrance for arboviruses but not enteroviruses.

Glycoproteins are commonly associated with virus spikes. Virus spikes are protein structures that extend from the surface of a virus and play a crucial role in the virus's ability to infect host cells. These spikes are often composed of glycoproteins, which are proteins that have attached carbohydrate molecules. The glycoproteins on virus spikes allow the virus to attach to specific receptors on the surface of host cells, enabling the virus to enter and infect the cell. Therefore, glycoproteins are closely associated with virus spikes and their ability to infect host cells.

In the acute phase of viral infection, the virus actively replicates and produces a large number of progeny viruses. This rapid replication leads to the characteristic symptoms of viral infection. However, during the latent phase, the virus remains dormant and does not actively replicate. Therefore, multiple rounds of replication occur in the acute phase of viral infection but not in the latent phase.

A capsid is the major protein component of the shell of the core. It is the protective protein coat that surrounds the nucleic acid (DNA or RNA) of a virus. The capsid is responsible for protecting the viral genome and facilitating its entry into host cells. It also plays a role in the assembly and release of new virus particles.

The correct answer is "Membrane surrounding virus core." This is because the envelope refers to the outer layer or membrane that surrounds the core of a virus. The envelope is composed of lipids and proteins and is derived from the host cell's membrane during the process of viral replication. It plays a crucial role in the virus's ability to infect and enter host cells.

Non-enveloped viruses are characterized by the absence of a lipid envelope surrounding their protein coat. Unlike enveloped viruses, which can enter host cells through fusion with the plasma membrane, non-enveloped viruses cannot fuse directly with the plasma membrane. Instead, they rely on other mechanisms such as receptor-mediated endocytosis or direct penetration through the plasma membrane to gain entry into the host cell. Therefore, the correct answer is penetration through the plasma membrane.

Nine HPV types increase risk for developing reproductive cancer
2 account for 70% of metastatic tumors

only 1% of patients with viremia develop cns involvement

Enteroviruses enter the body at one specific site and then cause disease in that particular area. However, they are also capable of spreading to other parts of the body, leading to systemic infections. This ability to spread from the initial site of entry is a characteristic feature of enteroviruses. Therefore, the statement "enter at one site and cause disease then spread" is true about enteroviruses.

Vaccination of children can sometimes lead to virus-induced immunopathology. This refers to a situation where the immune response triggered by the vaccine actually causes damage to the body's tissues. In some cases, the immune response can be too strong or misdirected, leading to inflammation and tissue damage. This is a rare occurrence but can happen with certain vaccines. It is important to note that the benefits of vaccination in preventing infectious diseases far outweigh the potential risks of immunopathology.

Viruses are classified based on various factors such as type of replication, structure of the virion, type of nucleic acid, and structure of the virus. However, the host required for survival is not a factor used to classify viruses. This means that the dependence on a host for survival is not considered when categorizing viruses into different groups.

A virion refers to a single virus particle. It is the complete infectious unit of a virus that consists of nucleic acid (DNA or RNA) enclosed in a protein shell called a capsid. The virion is capable of infecting a host cell and reproducing, leading to the spread of the virus.

Humans are susceptible to monkeypox and cowpox

Herpesviruses replicate within the nucleus. This is because herpesviruses are DNA viruses, and the replication of DNA generally occurs within the nucleus of eukaryotic cells. The viral DNA is transported into the nucleus where it utilizes the host cell's machinery to replicate its genome. This allows the virus to produce multiple copies of its DNA and ultimately generate new viral particles. Replicating within the nucleus also provides protection for the viral DNA from cellular defense mechanisms, allowing the virus to efficiently replicate and establish infection.

Influenza - Enveloped Segmented Single-Stranded RNA Viruses

Adeno refers to adenovirus, which is not a segmented RNA virus. Adenoviruses have a double-stranded DNA genome and do not possess segmented RNA. Segmented RNA viruses, on the other hand, have their genetic material divided into separate RNA segments. Examples of segmented RNA viruses include Bunyavirus, Influenza virus, and Rotavirus.

Non-enveloped viruses are able to freely cross the plasma membrane. Unlike enveloped viruses that require endocytosis into the cell, non-enveloped viruses can enter the cell by directly crossing the plasma membrane. This is possible because non-enveloped viruses have a more stable capsid structure that allows them to withstand the harsh conditions of the extracellular environment and pass through the plasma membrane without the need for specific sites or clathrin-coated pits.

Cold climate is most likely to reduce arbovirus infections because arboviruses are primarily transmitted by insects, such as mosquitoes, which are more active in warm climates. In cold climates, the activity and population of these insects decrease, reducing the transmission of arboviruses. Additionally, cold temperatures can also directly affect the survival and replication of arboviruses, further reducing their spread.

Togovirus may be responsible for causing rash and arthritis. Togovirus is a type of virus that belongs to the family of viruses called Flaviviridae. It is primarily transmitted to humans through the bites of infected ticks. Togovirus infections can lead to symptoms such as fever, headache, muscle and joint pain, and in some cases, a rash and arthritis. While it is not as well-known as diseases like dengue or yellow fever, Togovirus can still cause significant health issues in affected individuals.

Viruses replicate by using the host's cellular machinery, whereas bacteria undergo binary fission to reproduce. This means that viruses rely on a host organism to replicate, while bacteria can replicate independently. Therefore, the statement "replicates with host mechanism" accurately describes viruses but not bacteria.

Polyomaviridae is a double stranded DNA virus. This family of viruses includes several species that infect mammals, including humans. The double stranded DNA genome of polyomaviruses allows them to efficiently replicate and produce viral proteins. These viruses are known to cause various diseases in humans, such as polyomavirus-associated nephropathy and progressive multifocal leukoencephalopathy.

Immunoglobulin injections are the best treatment for a patient with polio infection. Polio is caused by a virus, and antiviral drugs are not effective against it. The Salk vaccine is administered intramuscularly, not intravenously, and is used for prevention rather than treatment. The Sabin vaccine is given orally and is also used for prevention. Immunoglobulin injections contain antibodies that can help the body fight off the virus and reduce the severity of symptoms. Therefore, immunoglobulin injections are the most appropriate treatment option in this case.

Single stranded positive sense RNA viruses have nucleic acid that functions directly as mRNA. This means that when these viruses enter a host cell, their RNA can be immediately translated into proteins by the host cell's ribosomes without the need for any additional steps. This is because the RNA of these viruses has the same polarity and sequence as the mRNA that is normally produced by the host cell. As a result, the host cell can directly use the viral RNA as a template for protein synthesis.

Togaviridae is a single stranded RNA virus. This family of viruses includes the genus Alphavirus, which are enveloped viruses with a positive-sense, single-stranded RNA genome. These viruses are known to cause diseases such as chikungunya and eastern equine encephalitis in humans.

Adsorption is the process by which a virus attaches to a host membrane. It is a random and reversible process, meaning that the virus can attach and detach from the host membrane multiple times. Nonenveloped viruses attach to host cells via exposed capsid regions. However, it is not true that adsorption requires ATP. ATP (adenosine triphosphate) is a molecule that provides energy for cellular processes, but it is not involved in the adsorption of viruses to host cells.

The correct answer is Rubella – Edmonston zagreb. The Edmonston zagreb strain is actually used in the measles vaccine, not the rubella vaccine. The rubella vaccine uses the RA 27/3 strain.

may involve specialized "replication complexes"

has restricted tropism

The given question describes a patient with a viral infection and various immune system deficiencies. The options provided are weakened cellular immunity, defective complement system, low antibody response, and age. The correct answer is weakened CMI, which stands for weakened cell-mediated immunity. This means that the patient's immune system is not effectively responding to the viral infection at the cellular level, making it difficult to eliminate the infection. The other options, while also potentially impacting the immune response, do not directly address the cellular immune response.

Hepadnoviridae is the correct answer because it is a family of viruses that have a mixed-stranded DNA genome. This means that the genome of these viruses contains both single-stranded and double-stranded regions. The other options, Reoviridae, Rhabdoviridae, Poxviridae, and Parvoviridae, do not have mixed-stranded genomes.

All of the viruses mentioned in the options (picornoviruses, rhinoviruses, and enteroviruses) can be considered positive sense. Positive sense viruses have RNA genomes that can be directly translated into proteins by the host cell's machinery. These viruses do not require a separate step of RNA synthesis before protein synthesis can occur. Therefore, all the mentioned viruses can be considered positive sense.

Enterovirus and coxsackievirus have been found to be linked to the development of Type 1 Diabetes Mellitus. Several studies have shown that these viruses can trigger an autoimmune response in the body, leading to the destruction of insulin-producing cells in the pancreas. This link between viral infections and Type 1 Diabetes Mellitus suggests that these viruses may play a role in the development of the disease. Therefore, the statement that Enterovirus and coxsackievirus are not linked to Type 1 Diabetes Mellitus is incorrect.

Plasma membrane, endoplasmic reticulum, golgi aparatus, or nuclear membrane.

Hemagglutinin (H) is the correct answer because it is responsible for binding the influenza virus to host cells and facilitating the fusion of the viral envelope with the host cell membrane. This allows the virus to enter the host cell and initiate infection. Neuraminidase (N) is involved in the release of newly formed viral particles from infected cells, while M2 is a proton channel that plays a role in viral replication but is not directly involved in binding or fusion with host cells.

for the posterior pharynx

Capsids of viruses self-assemble, meaning they spontaneously come together to form the outer protein shell of the virus. This process does not require any external factors or assistance. The capsid is responsible for protecting the genetic material of the virus, which can be DNA or RNA. It can take on different shapes, such as icosahedral or helical, but the icosahedral form can vary in size while the helical form has a defined set of subunits. Therefore, the correct answer is that capsids self-assemble.

double stranded RNA virus

Adenoviidae, Poxviridae, and Herpesviridae are classified as double-stranded DNA viruses. This means that their genetic material consists of two strands of DNA that are complementary to each other. These viruses replicate their DNA using a double-stranded intermediate, and their genetic information is encoded in the form of double-stranded DNA.

It is likely that the majority of viruses cause no disease.

The best target for the treatment of viral diseases is unique viral enzymes. Viral enzymes play a crucial role in the replication and survival of the virus within the host. By targeting these specific enzymes, it is possible to disrupt the viral replication process and inhibit the spread of the virus. This approach can help in developing antiviral drugs that specifically target the viral enzymes, minimizing the potential for side effects on host cells. Targeting infected animals, unique viral DNA, or infected host cells may not be as effective in treating viral diseases as they do not specifically address the viral enzymes responsible for viral replication.

Small pox is eradicated. NOT the virus.
2 laboratories in USA and Russia still contain the virus.

for minor

Single stranded negative sense RNA viruses use the genome as a template to make mRNA transcripts corresponding to each viral gene. In these viruses, the RNA genome is complementary to the viral mRNA, and therefore, the viral RNA needs to be transcribed into positive sense mRNA before it can be translated into proteins. This process is carried out by the viral RNA-dependent RNA polymerase, which synthesizes the mRNA transcripts using the viral genome as a template.

This virus is classified as DS RNA because it requires its genetic material to be copied into positive sense SS-RNA. DS RNA viruses have a double-stranded RNA genome, which means they have two complementary strands of RNA. In this case, one of the strands is copied into positive sense SS-RNA, allowing the virus to replicate and produce proteins.

The correct answer is VLDL and ICAM1. Rhinovirus, which is the causative agent of the common cold, must bind to specific receptors on the surface of host cells in order to infect them. In this case, the virus binds to two receptors, VLDL (Very Low-Density Lipoprotein) and ICAM1 (Intercellular Adhesion Molecule 1). These receptors play a crucial role in facilitating the entry of the virus into the host cells and initiating the infection process.

HPV infection is limited to the basal cells of stratified epithelium, the only tissue in which they replicate.

90% of individuals infected with high-risk HPV infections clear the viral infection within two years.

The correct answer is "attaches to receptors before replication." This means that the poliovirus must first attach to specific receptors on the surface of host cells before it can begin the process of replication. This attachment allows the virus to enter the host cell and hijack its cellular machinery to replicate itself.

adenoviruses are DS NONenveloped!

Poxviruses replicate in the cytoplasm. This means that the replication process of these viruses takes place outside of the nucleus of the host cell. Unlike most other viruses, which replicate within the nucleus, poxviruses have their own machinery to replicate their genetic material and produce new virus particles in the cytoplasm. This allows them to avoid the host cell's defense mechanisms and efficiently produce large amounts of viral progeny.

This statement suggests that arboviruses have the potential to cause damage to neurons or the liver. It implies that these viruses can specifically target these tissues and potentially lead to negative effects on their functioning. This answer option does not mention anything about tissue damage being reversible by antitoxins, dengue fever targeting mononuclear cells, or yellow fever creating cross-reacting antibodies.

Rabies - Bullet | Pox - complex symmetry

All have a protein capsid and envelope: This statement is not true regarding viruses. While many viruses do have a protein capsid, not all of them have an envelope. Some viruses, such as bacteriophages, do not have an envelope.

Viruses are different from bacteria because they do not replicate by binary fission, which is the process by which bacteria divide and reproduce. Additionally, viruses are smaller in size compared to bacteria. Therefore, the correct answer is A and B.

HPV Type 45 is a high-risk HPV type which is strongly associated with adenocarcinoma, a less common but aggressive cancer arising from the endocervical glandular epithelium.

The chronic phase of viral infection is characterized by the presence of RNA viruses. This phase occurs when the virus is able to establish a persistent infection in the host, often leading to long-term or lifelong infections. During this phase, the virus replicates and persists in the body, causing ongoing symptoms or disease. This phase is typically seen in infections caused by RNA viruses rather than DNA viruses.

DS Enveloped
SS nonenveloped
DS Noneveloped all do

A defective virus is a virus that needs simultaneous infection. This means that it requires the presence of a helper virus in order to complete its life cycle and replicate. Without simultaneous infection, the defective virus is unable to reproduce on its own. This makes it dependent on another virus to provide the necessary machinery and components for replication.

During hematogenous spread, bacteria can spread through the bloodstream and then replicate in different parts of the body. This process can occur without causing any symptoms, which is known as being asymptomatic. It is also possible for individuals with hematogenous spread to not experience prodromal symptoms, which are early signs or symptoms that precede the onset of a disease. Therefore, the correct answer is "can be asymptomatic."

For enveloped viruses, assembly typically occurs at the site of membrane acquisition - nucleus, ER/golgi, plasma membrane.

Antigenic DRIFT (random DNA mutations) in Influenza A is what causes the new seasonal strains we see most years

orthomyovirus (RNA virus that causes influenza)replication occurs in the nucleus, not the cytoplasm.

Nonenveloped viruses are released from host cells by cell lysis. This means that the virus particles cause the host cell to burst open, releasing the viral particles into the surrounding environment. This is in contrast to enveloped viruses, which are typically released by budding, where the virus acquires a portion of the host cell's membrane as it exits. The option "disrupt cell membrane and bind to m proteins" is not a correct description of the release of nonenveloped viruses.

This question is asking for the statement that is not true regarding capsids. The correct answer is "Only A and B". This means that it is not true that capsids are composed of repeating subunits and able to self-assemble into virions. Capsids are indeed composed of repeating subunits and have the ability to self-assemble into virions. The other statements in the question are true, such as the helical structure having a fixed number of subunits and being spherical in shape.

CIN2 is considered a high-grade lesion that may regress spontaneously in 40 percent of women.

Also, there is aSignificant relationship between HHV-6 and Hodgkin’s lymphoma, oral carcinoma, certain T-cell leukemias

DNA viruses are best linked to transcription in the host nucleus. This is because DNA viruses have their genetic material in the form of DNA, which needs to be transcribed into mRNA in order to be translated into proteins. Transcription is the process by which the DNA sequence is copied into mRNA by the host cell's transcription machinery, which takes place in the nucleus of the host cell. Therefore, transcription in the host nucleus is the most appropriate association for DNA viruses.

Both polivirus and rhinovirus share the similarity of needing to bind to receptors in order to replicate. This means that both viruses require specific receptors on host cells to attach to and enter the cells in order to replicate and cause infection. This is a common characteristic among many viruses, as they rely on host cell machinery for their replication and survival.

Nonenveloped viruses do not have an outer lipid envelope, so they cannot use glycoproteins for adsorption like enveloped viruses. Type III secretion system is a mechanism used by bacteria to deliver virulence factors, so it is not relevant to the adsorption of nonenveloped viruses. Nonenveloped viruses can only attach to specific sites on host cells, which allows for specific recognition and binding. The correct answer, "exposed regions of capsid proteins," is consistent with the fact that the capsid proteins of nonenveloped viruses are responsible for attachment to host cells.

Prions are best described as proteins similar to that of normal cells. Prions are misfolded proteins that can cause other proteins to misfold as well, leading to the formation of abnormal aggregates in the brain. They do not contain nucleic acid and are not surrounded by an infectious protein capsid. Prions are also not susceptible to proteolytic enzymes.

The correct answer is "causes lytic destruction of host cell tissue." Poliovirus is known to cause lytic destruction of host cell tissue. This means that the virus replicates within the host cells and causes the cells to burst, leading to tissue damage. This destruction of host cell tissue is one of the characteristic features of poliovirus infection.