Virology, Essay Example

To find general information about hemorrhagic fevers via the World Wide Web, what search engines and sites would you use? What keywords would you use in your searches?

In order to locate information regarding viral hemorrhagic fevers, it is important to use search engines such as Google, and this would lead me to websites such as the Centers for Disease Control, the Mayo Clinic, the National Institutes of Health, and a number of state websites that provide information regarding this type of fever. I used the keywords “viral hemorrhagic fever” to conduct the search.

How would you find research papers pertaining to viral hemorrhagic fever? List your resources and the titles of the journal articles. Where was the research conducted?

I would use Google Scholar in order to locate specific resources regarding hemorrhagic fever. This search provides many different journal articles and books regarding the topic, including journals such as Current Opinion in Virology, Annual Review of Pathology, Journal of Virology, and PlOS Neglected Tropical Diseases, among others.

Chapter 2

Rashes can be explained by a variety of causes. List a few possibilities.

Rashes may be caused by such factors as skin irritation with an unfavorable substance, such as a poisonous plant, a type of soap or perfume, a type of fabric, latex, and any number of viral infections. Rashes may also represent a type of skin condition that is chronic in nature, or an allergic reaction to a medication. Finally, some rashes are a side effect of a more serious disease, such as cancer.

Could additional cases be caused by a new or yet-to-be-identified virus? Why or why not?

Yes, as there is a significant possibility that new types of viral infections could emerge at any given time, thereby posing a risk of rash to patients.

The CDC points to several challenges that impede investigations of reported rashes among schoolchildren and the identification of their causes. List these challenges.

These challenges include the lack of reporting of symptoms that might occur in children, thereby limiting the information that public health officials have in regards to a rash. Therefore, diagnosis and treatment cannot begin in a timely manner and could create problems for children.

Chapter 3

Mimivirus has been proposed as the sole member of a new virus family Mimiviridae whose members are classified as large nucelocytoplasmi dsDNA viruses. This virus significantly challenges the evolution and definition of a virus. Discuss this.

Mimivirus is the most complex virus that has ever been identified. It is much larger in size and uses a host as its means of translation, and is distinct from many other types of viruses because it does not have the same properties, including a lack of ribosomes. These factors demonstrate that the virus is highly unique and represents a challenge to researchers to identify its true origins and purpose.

Based on ribosomal RNA analysis, where would you tentative propose to place Mimivirus in the three-doman “Tree of Life” hypothesized by Carl Woese?

It is believed that Mimivirus does not fall under any of the current scenarios of the tree of life, and that perhaps it is a new branch that is unique from all other existing viruses, particularly since it does not have ribosomes.

3.Many have debated the issue of whether or not viruses are alive. Besides the inclusion of a partial translational machinery apparatus, Mimivirus carries other genes that have not been identified in any other known virus. Research these genes and their functions.

The genes within the Mimivirus that are associated with DNA repair, translation, and metabolism have not existed in the same form in past viruses; furthermore, they were acquired through a process known as horizontal gene transfer. Some genes are similar to those in eukaryotes, while others are similar to bacteria.

Viruses and the nuclei of cells share some structural similarities. List these similarities.

Viral DNA is able to be integrated into the cell nucleus because its pore ruptures and enables this DNA to enter the nucleus without difficulty, thereby increasing its replication properties.

From an evolutionary standpoint, could a virus have provided the first nucleus? Or was a nucleus something an early bacterial cell evolved on its own or in partnership with an archaeum?

It is possible that a virus generated the first nucleus, and in this case, a virus that was living in an archaeum was responsible for creating the nucleus and the genetic material that evolved during that merger.

Chapter 4

hMPV and RSV belong in the Paramyxoviridae family. What type of nucleic acid genome do they have? Do they encode their own viral polymerase?

This genome includes approximately 15,000 nucleotides, an RNA strand encompassing negative polarity, and 10 genes that encode 11 proteins. These viruses represent a reverse-transcriptase polymerase chain reaction (RT-PCR).

How many genes does hMPV have in its genome?

hMPV includes genes that code for nucleoprotein, matrix protein, phosphoprotein, fusion protein, small hydrophobic surface protein, major attachment glycoprotein, and major polymerase subunit.

The first report of a fatal encephalitis case associated with hMPV was established in the CDC’s Emerging and Infectious Diseases publication in 2005. The authors recommended screening for patients, especially children with encephalitis symptoms of unknown origin. What is encephalitis?

Encephalitis is a type of brain inflammation that is most commonly caused by herpes simplex virus; however, mosquitoes also carry a virus that may cause the condition in some cases, along with ticks and West Nile versions. Symptoms are often flu-like, including fever, headaches, muscle aches, and fatigue. Many complications may occur from encephalitis if left untreated, including coma and eventual death. Treatments may include antiviral drugs, including Acyclovir, particularly when herpes simplex virus is the primary cause.

Have neurological symptoms been associated with other viruses in the Paramyxoviridae family? If so, which viruses?

Other viruses within this family may lead to neurological symptoms, including Hendra virus, which was first discovered in Australian horses and humans, and Nipah virus, which was identified in adult males in Malaysia and Singapore after they came in contact with infected pigs.

Chapter 5

Early recognition of meningitis and/or encephalitis requires rapid diagnosis. Why?

Viral meningitis and encephalitis, if left undetected, may cause serious complications, including coma and death. The virus results is significant brain damage at a rapid rate; therefore, diagnosis and treatment must be achieved as early as possible to prevent further complications from occurring in this patient population.

Besides the viruses presented in the case study, what other viruses can cause meningitis or encephalitis in humans?

The primary causes of viral meningitis include enteroviruses such as Coxsackie and Echoviruses within the enterovirus family. In addition, herpes simplex virus may cause meningitis and encephalitis, the former caused by HSV-2 and the latter caused by HSV-1. In addition, HSV viruses may cause recurrent lymphocytic meningitis in some patients.

Besides nucleic acid amplification, what other methods can be used to detect viruses that cause central nervous system infections and how long do these test results take?

The use of PCR technique is the standard method to identify herpesvirus that cause central nervous system infections. However, recent studies demonstrate that a DNA microarray test known as the Clart Entherplex kit could also play a valuable role in this process. Regardless of the method, sensitivity must be high in order to detect viral nucleic acids.

Chapter 6: Gene Therapy

Is gene therapy a permanent cure for any condition?

Gene therapy is a highly beneficial alternative for some patients because it provides some relief in treating various conditions or diseases. However, gene therapy is a complicated process that may or may not have lasting or permanent benefits. If germ line cells are treated with gene therapy, then it is possible that the changes are permanent and will impact future generations. However, in cases where gene therapy take place later on, there is a likelihood that these treatments will not be permanent in nature.

Can gene therapy be used for disorders that arise from mutations in more than one gene?

Gene therapy is not the most feasible alternative for disorders that arise from mutations that occur in more than one gene. Gene therapy is likely to be more effective in situations that involve a single gene mutation, particularly when using somatic gene therapies, in diseases such as cystic fibrosis and hemophilia.

What types of viruses are used in gene therapy? What are their advantages and limtiations?

Virus vectors are often used in gene therapy as a means of altering gene expression and the presentation of disease. This is accomplished by using retroviruses, adenoviruses, herpes simplex virus, and adeno-associated viruses.

Will gene therapy patients mount an immune response against the virus vector used in treatments?

It is likely that some patients will respond to gene therapy, but that there is also a greater risk that the introduction of viral vectors may lead to an increased immune response that could alter the function of the gene therapy. In addition, it is possible that some patients will experience challenging and harmful side effects, for which the body will establish the aforementioned immune response to fight these symptoms and the impact of the vectors within cells.

Are there toxic effects related to gene therapy treatments?

A number of toxic effects may occur with the introduction of viral vectors, thereby creating a situation that may no longer be beneficial to patients, as it may cause intolerable side effects or toxic consequences for patients.

Are there examples of patients who had major complications related to gene therapy and how was the problem resolved?

A number of patients have experienced complications as a result of gene therapy. A notable case involved a patient with liver disease in 1999 who died after experiencing an inflammatory response to adenovirus vector. Therefore, to avoid these types of complications, investigators have sought methods of introducing viral vectors outside of the body, and administering low doses of the virus, along with drugs to suppress the immune system and a subsequent immune response to the treatment.

What are some of the ethical considerations for using gene therapy?

Gene therapy is a dangerous alternative and poses many risks to patients in clinical trials, including death. Therefore, regulation and oversight regarding gene therapy within clinical trials must be carefully and continuously monitored in order to promote ethically responsible practices associated with gene therapy treatments.

Gene therapy is expensive. Who has access to these therapies and who pays for their use?

Gene therapy is only offered in experimental environments in the form of clinical trials; therefore, private companies often pay for these treatments, perhaps in conjunction with private health insurance. The NIH offers a list of clinical trials that are available to patients, so discussions with a physician are essential to determine if a patient qualifies for a gene therapy clinical trial.

Chapter 7: Measles

LCMV infection is either asymptomatic or causes a mild, self-limiting illness in healthy persons. Discuss reasons why four of the organ recipients were at higher risk for LCMV.

Organ recipients were at higher risk for LCMV because they were potentially exposed to wild rodents, they had cared for pet hamsters in the home environment, there was a common donor between the recipients, and rodent care was performed by the primary recipients.

Who else is at risk for LCMV infection? Why?

Pregnant women face a significant risk of infection, thereby supporting the belief that they should not care for rodents in any capacity while pregnant or when trying to become pregnant. In addition, any other persons who are immunosuppressed should exercise caution in these cases.

Family members of the donor tested positive for LCMV antibodies. LCMV was isolated from the pet hamster. The family member who cared for the pet hamster had both high IgM and Ig-specific LCMV antibodies in her blood. What does IgM indicate?

IgM is an indicator of anti-mouse immunoglobulin M, and this reflects the potential for isolating antibodies that are potentially able to fight LCMV infection in humans.

How will scientists determine whether the LCMV isolated from the hamster is the same LCMV that infected the organ recipients?

The use of epidemiologic data provides a basis for exploring the identification of LCMV in patients, and is perhaps the most useful means of identifying the virus in human patients.
How is LCMV transmitted to rodents?

LCMV is carried by infected mice, including feces, saliva, and urine, who then may transmit the virus to pet hamsters in the pet store or the home environment through exposure with infected mice.

If you own a pet hamster, what precautions should you take after handling it and cleaning the cage?

Most importantly, cross-ventilation in the area is necessary, along with the use of latex gloves, disinfectants, and the proper disposal of rodents, along with the active use of soap and water after removing gloves.

How would you clean a rodent-infested area such as a dusty garden shed?

The use of disinfectants is essential, along with the removal of any materials from the area that might be affected.

Chapter 8: Musicians and Viral Infections

Whom would you agree or disagree with and why?

High-risk behaviors are a staple in the lives of many musicians, particularly those who experience fame and fortune; therefore, it is not surprising to discover a potentially higher incidence of viral infections within this population group.

Research the average life expectancy of humans. What was the average life expectancy during the baroque period? The classical period? Today?

During the baroque period, the average life expectancy was approximately 35 years of age, and during the classical period it was an average of 40 years of age. Today, men have a life expectancy of 76 years, and 81 years for women.

What is Jeffrey Sartin’s assessment of innovative musical artists? Are they more at risk for contracting and dying from an infection? Why or why not?

Innovative musical artists have a greater tendency to commit to non-traditional lifestyles, whereby they face a greater risk of viral infection, drug abuse, and other challenges that might not occur in some other population groups.

Perform additional literature research. Create a list of at least ten famous musicians and their cause of death.

Some famous musicians and their causes of death include the following: 1) Sid Vicious (heroin overdose); 2) Buddy Holly (plane crash); 3) Selena (homicide); 4) Karen Carpenter (heart failure due to anorexia nervosa): 5) Kurt Cobain (suicide); 6) Amy Winehouse (alcohol poisoning); 7) Andy Gibb (myocarditis); 8) Bob Marley (cancer) 9) Marvin Gaye (gunshot wound); 10) Cass Elliott (heart attack).

Compare deceased musicians from different genres of music. Is there any correlation between the type of music generated by the artist and his/her risk for contracting a lethal infectious disease? Explain your answer.

In recent decades, rock n’ roll musicians have succumbed to many different types of conditions, most notably, drug overdoses, while those in the rap genre are more likely to succumb to violence. However, there are many different causes of death across many genres of music to consider.

Chapter 9: Xenozoonosis

What are the major obstacles to confronting xenotransplantation?

Xenotransplantation is highly questionable from an ethical point of view, and it represents a much higher risk of infection to many patients, who could spread these infections to other persons under different conditions.

Can the safety of human recipients be guaranteed?

The safety of human recipients cannot be guaranteed, as this type of procedure is high risk and represents a challenge to the medical community due to its high risk nature.
What ethical arguments can be made against the ethical use of animals in this way?

There is a potential advantage for humans in treating diseases such as diabetes; however, the ethical risks are also great, as this type of procedure is not yet proven effective in a sufficient number of cases. In addition, animals must be treated with additional caution if being considered for these procedures.

Is xenotransplantation the only way in which to tackle the donor deficit problem?

Xenotransplantation is a possible alternative to address disease and the need for organ transplantation; however, other alternatives should also be considered, such as life-prolonging procedures for patients requiring transplants.

Given the history of viruses crossing the species barrier, is xenotransplantation too risky?

This procedure leads to many high risks that must be considered when addressing the potential benefits of this practice for human patients.

Chapter 10: Cancer Therapy

Given your new knowledge of oncolytic viruses, the idea of engineering measles virus against cancer isn’t just science fiction. Compared to standard forms of cancer therapy like chemotherapy and radiation, why are oncolytic viruses less toxic to the patient?

These viruses are less toxic because they are able to be administered in smaller doses without any observed toxic effect. However, their ability to fight tumors is not yet proven effective in sufficient clinical trials.

List the characteristics of an “ideal” replicating oncolytic virus.

An ideal virus is injected directly into a tumor to destroy the tumor, as well as to generate an anti-tumor response in the host.

Are there viruses that turn humans into darkseekers? What types of characteristics would a virus have to create a darkseeker?

This appears to be a work of science fiction, but it raises interesting questions regarding the ability of human beings to be effective communicators in the transmission of viruses to fight disease.

Is serum used as a vaccine? Is serum used to cure individuals of viral infections? Explain your answer.

Serum is used as a vaccine in some variations and as a form of growth media to enable viruses to grow in a laboratory environment.

Most adults have  preexisting immunity to measles through vaccination. Discuss how this may be a roadblock and/or a safety feature in the use of a modified measles virus as a cancer therapy.

The Measles virus may serve as a viable cancer treatment in some cases, but existing immunity may pose a problem. Therefore, it is important to identify cell carriers and immunosuppressant drugs that may overcome this obstacle when using measles for this purpose.

Using oncolytic viruses to treat cancer is not a new idea. Speculate why its use was abandoned and why there is interest today.

This is a potentially beneficial means of fighting cancer tumors; however, it poses a high risk. If these risks are minimized, then it is possible to achieve the desired results with this treatment method.

Chapter 11: Echovirus-4

What is the most frequent travel-related illness among individuals going from industrialized countries to developing regions?

The most common illness is diarrhea, which is caused by different strains of E. coli bacteria within developing countries.

Do you think all of the sick travelers were infected by the same source? Explain your answer.

It was possible that the travelers were infected by the same source, particularly if it included the same type of food or same source of water that was used.

What is the suspected source of contamination in this case?

The suspected source of contamination is the local water supply.

What are possible routes of transmission?

Contaminated water is a likely route of transmission to humans in this case, along with exposure to fecal matter.

In what countries is Echovirus-4 present?

This virus is present in countries such as Australia, India, and China.
What dietary recommendations would you follow if you were to travel to certain parts of India? Gambia? Thailand? Brazil? Kenya? Nepal?

It is recommended not to drink tap water, not to eat meat, eggs, or milk, uncooked vegetables, and fish, and only eat in restaurants that are upscale or that are designed for tourists.

How do echoviruses differ at the molecular level from coxsackle viruses? From polioviruses? From other enteroviruses?

Echoviruses are different because they are nondeveloped and have a different type of configuration than the other viruses mentioned, and are resistant to alcohol and ether.

Do all members of the Picornaviridae family cause the same diseases? Elaborate upon your answer.

This family of viruses encompasses a wide range of diseases, including but not limited to meningitis, hepatitis, and the common cold, all of which possess a variety of symptoms in many patients.

Chapter 12

Which countries are currently affected by a highly pathogenic avian influenza strain that infects humans?

Avian influenza affects countries such as Indonesia, Egypt, Vietnam, Cambodia, China, Thailand, Turkey, and Bangladesh.

What are control measures for birds?

Control measures include protection areas to protect poultry from infection by wild birds, in addition to greater surveillance within affected communities.

How do outbreaks of avian influenza spread within a country?

This virus may spread through birds through shedding in saliva and feces to other non-infected birds. This may lead to transmission to poultry products and subsequent transmission to human beings.

How are humans infected?       

Humans are infected by poultry that has been infected by wild birds that have transmitted the virus.

In this case, list possible routes of avian flu transmission.

Avian flu transmission may occur through chickens, pigs, and ducks; however, birds often transmit the virus to poultry that humans then ingest, or they are transmitted through another type of host, such as a pig.

List good hygiene practices to avoid spreading the virus through food.

Cooking all poultry products at the proper temperature and only purchasing poultry that looks appropriate and from reputable vendors is ideal to prevent the spread of the virus.

Will an annual flu shot protect humans from avian influenza?

The standard flu shot does not protect humans from the virus; however, an experimental vaccine is under consideration.

Works Cited

Schildgen, Verena, et al. “Human Metapneumovirus: lessons learned over the first decade.” Clinical microbiology reviews 24.4 (2011): 734-754.