Assignment/Assessment (Ch. 25) Micro

Please choose the answer that describes the progression of HIV infection to AIDS to test your understanding of how AIDS is defined as a disease

ALL CHOICES Early presentation resembles a vague mononucleosis-like condition, with a rapid increase, then decrease of HIV virus particles in the blood. An extended period of latency which can last for years, during which time the patient's T-cell numbers are steadily decreasing, gradually moving toward the immune deficient (AIDS) state. The actual onset of AIDS is marked by fatigue, diarrhea, weight loss, and complications associated with various organs systems such as nervous, cardiovascular, respiratory, and gastrointestinal.

Influenza infection can be treated with

All of the choices are correct (amantadine; rimantadine; zanamivir; oseltamivir)

The abnormal form of the protein is designated

PrPsc

Please select the answers below that correspond to structural features of HIV and their host cells necessary for HIV infection to occur.

The HIV envelope contains glycoproteins that mediate viral absorption and fusion to the host cell injectable host cell membranes must present surface receptors including a CD4 marker, as well as a co-receptor

This term implies the constant and gradual change of influenza glycoproteins through mutation which decreases the host cells' ability to recognize the virus.

antigenic drift

This term implies a relatively sudden and dramatic change in the influenza virus genome through substitution or recombination of genes from an influenza virus originating from a different animal host.

antigenic shift

synthetic nucleoside reverse transcriptase inhibitor; mimicks an actual DNA base, resulting in a faulty reverse transcript which terminates the viral cycle

azidothymidine (AZT)

Please select the answers that explain why rhinovirus infections are typically limited to the upper respiratory tract.

being sensitive to the acid environments of the gut, rhinoviruses remain as high in the respiratory tract as possible to avoid these conditions unlike most human viruses, rhinovirus prefers a cooler environment than the human core temperature of 37 degrees C provides

A harmless PrP is converted into the infective PrP

by an abnormal PrP which binds to the normal protein and causes it to become misfolded.

Please choose the following mechanism or vector by which the causative agent of hantavirus pulmonary syndrome is believed to be transferred to humans.

by inhalation of the dried feces of an infected rodent

Please select each of the common reservoirs of rabies listed below.

canines skunks, raccoons, and badgers bats

Please select all of the correct answers that describe factors increasing the likelihood of human hosts contracting influenza.

contact with chickens, other poultry, and swine contact with other individuals in crowded areas with poor ventilation during winter months in seasonal areas inhalation of respiratory aerosols

Influenza vaccine

contains three or four different viral variants is created from flu viruses that have been chemically inactivated

Treating HIV infection with multiple drugs at the same time is advisable because

different strains of HIV may exist in the same person overcoming the effects of multiple drugs would require a virus to acquire multiple mutations simultaneously

Which of the following are unique characteristics of reoviruses?

double stranded RNA genome double-layered capsid

The provirus state exists when

double-stranded viral DNA is integrated into host cell chromosome.

Arboviral diseases may includes which signs and symptoms?

fever encephalitis rash localized bleeding joint pain

The screening of donated blood for the presence of viruses greatly reduced the frequency of transmission of

hepatitis B virus hepatitis C virus HIV

Please select each of the options below that describe structural characteristics of influenza virus.

influenza viruses are enveloped segmented single-stranded RNA viruses influenza viruses possess hemagglutinin, named for its ability to clump red blood cells

Rubella

is particularly serious for pregnant women is often asymptomatic can be prevented through vaccination can cause miscarriage and birth defects

Results are available within minutes.

latex agglutination test

Prions are believed to cause _______ diseases.

neurodegenerative

protease inhibitor that blocks the action of those HIV proteases involved in final assembly of the HIV virus particles

norvir

Treatment of Creutzfeldt-Jacob disease relies upon

nothing. Creutzfeld-Jakob disease has no treatment

If the DNA of the provirus is transcribed,

one long polygenic mRNA is produced.

Complications of influenza infection include

pneumonia as a result of secondary infection with Strptococcus pneumonia pneumonia as a results of secondary infection with Staphylococcus aureus

Please select the answers below that correspond to characteristics of polioviruses increasing their likelihood of transmission.

poliovirus can be transmitted in a fecal-oral fashion, passed from person to person through contaminated food, water, and other substances contaminated with feces polioviruses have a naked capsid making them resistant to harsh conditions such as those present in the host's gastrointestinal tract

reverse transcriptase inhibitor that actually binds and restructures the enzyme leaving it nonfunctional

sustiva

Please select each of the ecological factors of arthropod vectors that tie them to the life cycle of their particular arbovirus counterpart.

the arthropod's life span availability of the arthropod's food source and breeding site climatic influences such as temperature and humidity

Please select each of the answers that correspond to the epidemiology and pathology of Hepatitis A virus distinguishing it from other hepatitis viruses.

transmitted primarily in a fecal-oral fashion through ingestion of contaminated food and water infection is acute and temporary, rarely resulting in lasting liver damage

Retroviruses have

two copies of single-stranded RNA.

A warming worldwide climate is predicted to lead to an increase in the number of malaria infections because

warm regions capable of supporting the Anopheles mosquito will increase in size

Please choose the answer that best described the age group in which respiratory syncytial virus is the most prevalent cause of respiratory infection.

young infants

The virus HTLV-1 is associated with

adult T-cell leukemia

requires days or even a week before results are available

ELISA test

If the virus is present as a provirus in the host cell, it remains latent and never produces new virus.

False

Please select the answers below that correspond to reasons for the difficulty in the manufacture of an effective HIV vaccine.

HIV becomes later in host cells which serves to "hide" the virus from the host immune system HIV antigens mutate rapidly which decreases or eliminates the ability of host immune components to recognize them as foreign entities

Please select each of the diseases caused by coronaviruses listed below

a form of the common cold myocarditis enteric infections severe acute respiratory syndrome

The polygenic mRNA codes for making one long polyprotein which is then cleaved into the separate individual virus proteins.

True

Please select each arboviral disease that is transmitted by a mosquito vector.

West Nile virus yellow fever virus dengue fever virus

used to confirm initial positive test

Western blot