HII SAQs - Micro/Pharm Week 3

E

A 10-year-old girl presents with a temperature of 38.5° C and a macular rash on her trunk, face, and arms. She has several classmates with a similar illness. She has scattered raised papular lesions inside her mouth. The throat culture for group A beta-hemolytic streptococci is negative but a test for antiviral antibody in her serum is positive. Which of the following BEST DESCRIBES the genome of the virus that causes this disease? A.) double-stranded DNA of >100 kb B.) double-stranded DNA of <10 kb C.) double-stranded RNA D.) single-stranded RNA of + polarity E.) single-stranded RNA of - polarity

E

A 15-month-old girl presented to her pediatrician's office with fever of 39.2°C, swollen lymph nodes, and a vesicular rash on her trunk and upper arms. The vesicles were at various stages of development, some newly formed and some erupted with crust formation. This patient's symptoms were MOST LIKELY caused by: A.) smallpox virus. B.) Staphylococcus aureus. C.) measles virus. D.) papillomavirus type 1 . E.) varicella-zoster virus.

E

A 3-year-old child presents at the physician's office with symptoms of coryza, conjunctivitis, low-grade fever, and Koplik's spots. The causative agent of this disease belongs to which family of viruses? A.) adenoviruses B.) herpesviruses C.) picornaviruses D.) orthomyxoviruses E.) paramyxoviruses

D

A 31-year-old female diagnosed with AIDS presents with a progressive blurring of vision in her right eye. On funduscopic examination, a small white opaque lesion is noted on the retina of her right eye. Which of the following is the most appropriate therapy for this patient? A.) acyclovir B.) amantadine C.) flucytosine D.) ganciclovir E.) zidovudine

D

A 32-year-old woman visits her gynecologist for a routine Pap smear. A few small raised, flat lesions are observed on her cervix and several genital warts are observed on her vulva. Histology revealed moderate dysplasia. Presence of a DNA virus in cervical cells was confirmed by immunofluorescent antibody detection of viral antigens. Which of the following mechanisms would be MOST RELEVANT in explaining how the causative agent transformed this patient's cervical cells? A.) Viral protein E6 bound cellular RNA polymerase and caused mdm-2 overexpression. B.) Viral protein E7 caused genome instability by binding Ku70. C.) Viral genome inserted into host cell genome and caused c-myc overexpression. D.) Viral protein E6 caused degradation of cellular p53 protein. E.) Viral protein E7 bound cyclin B and disrupted cell cycle regulation.

E

A 41-year-old male presents in your office complaining of shortness of breath, chest pain, and multiple papular purple skin lesions on his legs. The patient denies homosexual contacts, but has a long history of IV drug use. Microscopic examination of the lesion biopsy showed multiple characteristic spindle cells and abnormally irregular and dense blood vessels. Which of the following is the MOST LIKELY cause of this patient's skin lesions? A.) measles virus B.) respiratory syncytial virus C.) adenovirus type 5 D.) molluscum contagiosum virus E.) Kaposi's sarcoma herpesvirus

C

A 56-year-old man developed symptoms consisting of headache, fatigue, general achiness and a distinct chill. Severe muscular aches ensued and his temperature rose to 103°F on the following day. Laryngitis, cough, and substernal soreness were noted. Physical examination revealed a slight tachycardia and slightly lower than normal blood pressure. The lymphoid follicles of the soft palate were enlarged and the nasal mucous membrane appeared bright red with areas of hemorrhage. The patient complained of loss of appetite and general weakness. 18. What mechanism is responsible for the emergence of new epidemic forms of this pathogen? A.) homologous recombination with similar viruses B.) an error prone replicase C.) antigenic shift D.) mutations in IBsAg E.) mutations in the matrix protein

C

A 6-year-old child presents with a fever and severe cough. A few days later, his baby sister has to be hospitalized due to respiratory distress, hypoxemia, hypercapnia, and pneumonitis. An immunofluorescence test is positive for an RNA virus. Which agent is the MOST LIKELY cause of this infection? A.) influenza C virus B.) measles virus C.) respiratory syncytial virus D.) adenovirus type 5 E.) rhinovirus type 2

E

A 68-year-old man presents with a chief complaint of intense pain on his left side for the past four days associated with a rash. He has a history of prostate cancer and has been receiving external beam radiation to treat spinal metastases for several weeks. On examination, multiple small vesicular lesions on an erythematous base are visible along the right side of the chest wall in a 4-6 cm stripe from the midline to the flank. Some of the lesions are fluid-filled, and some are crusted. Which infectious agent is MOST LIKELY responsible for this patient's condition? A.) Kaposi's sarcoma herpesvirus B.) lassa virus C.) measles virus D.) molluscum contagiosum virus E.) varicella-zoster virus

C

A developing country is experiencing a rise in the incidence of neonatal tetanus (first 28 days after the birth). Which of the following measures would be the most appropriate prevention measure to control the problem? A.) routine vaccination at birth B.) peripartal antibiotics C.) vaccination of pregnant mothers D.) early postpartum breast feeding E.) extended postpartum hospital stay

A

A female baby is born at 39 weeks gestation with a petechial rash, low birth weight, hepatosplenomegaly and bilateral cataracts. The symptoms are thought to be due to an infection acquired in utero. What infectious agent is MOST LIKELY responsible this clinical presentation? A.) cytomegalovirus B.) group B streptococcus C.) rubella virus D.) parvovirus B19 E.) herpes simplex virus type 2

E

A virus was isolated from the cerebrospinal fluid of a 42-year-old male with severe neurological symptoms. The virion was naked and the icosohedral nucleocapsid contained a singled-stranded RNA genome of positive-polarity. The virus MOST LIKELY belongs to which of the following families? A.) polyomavirus B.) orthomyxovirus C.) retrovirus D.) reovirus E.) picornavirus

D

According to recommendations issued by the U.S. Public Health Service, which of the following statements regarding vaccination against smallpox is true? A.) Pregnant women should be vaccinated in the first trimester. B.) Persons who have eczema should be vaccinated soon after diagnosis. C.) Persons who have immune deficiencies should be vaccinated every 5 years. D.) Persons traveling abroad need not be vaccinated. E.) Children should be vaccinated before they begin school.

C

An active 6-year-old boy presents with a cluster of pale, painless, pearl-like, umbilicated nodules on his neck. You are able to express a cheesy material from the center of one of the nodules, and explain to his mother that this infection is caused by a poxvirus. This common condition is called: A.) monkeypox. B.) carbuncles. C.) molluscum contagiosum. D.) warts. E.) chickenpox.

A

An example of a drug that targets a viral reverse transcriptase is: A.) lamivudine. B.) rimantadine. C.) enfuvirtide. D.) interferon. E.) acyclovir.

B

An immunocompromised person with history of seizures had an MRI that revealed a temporal lobe lesion. Brain biopsy results showed multinucleated giant cells with intranuclear inclusions. The MOST LIKELY cause of the lesion is: A.) hepatitis C virus. B.) herpes simplex virus type 1 . C.) yellow fever virus. D.) rabies virus. E.) parvovirus B19.

C

During replication of a virus, the defining feature of the eclipse phase is the: A.) lysis of virus-infected cells. B.) release of infectious virions from cells. C.) absence of infectious virions. D.) presence of intracellular infectious virions. E.) synthesis of viral mRNAs and proteins.

E

Each of the following has an RNA genome of positive-polarity EXCEPT for: A.) coxsackievirus. B.) hepatitis A virus. C.) hepatitis C virus. D.) human immunodeficiency virus. E.) rabies virus.

D

Genetic variation in viruses contributes to their ability to evade the immune response. What is the principal mechanism by which antigenic shift occurs in influenza A virus? A.) low fidelity of DNA-dependent DNA polymerase B.) low fidelity of RNA-dependent RNA polymerase C.) low fidelity of reverse transcriptase D.) reassortment of ssRNA segments E.) homologous recombination between RNA genomes

D

Genomic material of some RNA viruses can be 'infectious' when artificially delivered into cultured cells in a laboratory setting. RNA from which of the following viruses would MOST LIKELY be infectious? A.) Ebola virus B.) influenza virus C.) measles virus D.) yellow fever virus E.) Sin nombre virus

A

Hantavirus is an emerging pathogen that is best described by which of the following statements? A.) Influenza-like symptoms are followed rapidly by acute respiratory failure. B.) Hemolysis is common in infected patients. C.) It is acquired by inhalation of aerosols of the urine and feces of deer. D.) Transmission from human to human is common. E.) Effective antiviral therapy is available.

C

Hemagglutinin, one of the antigenic determinants of influenza, is responsible for which of the following functions? A.) replication of viral RNA B.) release of virions from host cells C.) attachment of virions to host cells D.) nuclear export of unspliced RNA E.) formation of ribonucleoprotein complexes

E

Hepatitis B virus is a major cause of hepatocellular carcinoma. Replication of its nucleic acid is depicted as a 4-step process: Which enzyme is most likely involved in step 2? A.) viral RNA polymerase B.) viral DNA polymerase C.) viral reverse transcriptase D.) host cell RNA ligase E.) host cell RNA polymerase

D

Hepatitis D virus (delta agent) is a defective virus that can replicate only in cells already infected with which of the following viruses? A.) hepatitis A virus B.) Epstein-Barr virus C.) hepatitis G virus D.) hepatitis B virus E.) human immunodeficiency virus

C

Infectious mononucleosis is a potentially debilitating viral disease, and is characterized by which of the following statements? A.) It is most prevalent in children less than 14 years old. B.) It is caused by human herpesvirus 8 . C.) It is caused by Epstein-Barr virus. D.) It is caused by varicella-zoster virus. E.) Ribavirin is the treatment of choice.

D

Latent infection is characteristic of which of the following virus groups? A.) picornaviruses B.) orthomyxoviruses C.) paramyxoviruses D.) herpesviruses E.) poxviruses

C

Mad Cow Disease has been highly publicized in Great Britain. This disease, which is similar to scrapie, is caused by: A.) a bacterium. B.) a fungus. C.) a prion. D.) a protozoan. E.) a virus.

E

Mumps virus accounts for 10 to 15% of all cases of aseptic meningitis in the United States. Which of the following statements about mumps virus is MOST ACCURATE? A.) Infection with mumps virus is apt to recur periodically in many affected persons. B.) Infection with mumps virus usually causes orchitis in adult males. C.) Mumps virus is maintained in an animal reservoir, which includes dogs. D.) Mumps virus infection usually produces severe systemic manifestations. E.) Mumps virus infection is preventable by immunization.

B

One of the most common sexually transmitted diseases that may lead to cervical carcinoma is caused by which of the following viruses? A.) cytomegalovirus B.) papillomavirus C.) hepatitis C virus D.) herpes simplex virus E.) human immunodeficiency virus

E

Reactivation of latent Varicella-Zoster Virus infection is a frequent cause of: A.) varicella. B.) encephalitis. C.) Burkitt's lymphoma. D.) herpetic whitlow. E.) post-herpetic neuralgia.

C

Reverse transcriptase is an enzyme unique to the retroviruses. Which of the following is a function of reverse transcriptase? A.) RNA-dependent RNA polymerase B.) synthesis of viral mRNA from proviral DNA C.) RNA-dependent DNA polymerase D.) replication of proviral DNA E.) integration of proviral DNA into the host chromosome

A

Rhinovirus is primarily transmitted by: A.) aerosolized droplets. B.) blood products or shared needles. C.) fecal-oral route. D.) sexual contact. E.) vertical transmission from mother to child.

A

Rotavirus infection in children is MOST OFTEN diagnosed: A.) using ELISA to detect anti-viral secretory IgA in the patient's stool. B.) using ELISA to detect anti-viral IgM in the patient's blood. C.) using Western blot to detect anti-viral IgG in the patient's blood. D.) using horse red blood cells to test for the presence of agglutinating antibodies. E.) using RT-PCR to measure rotaviral RNA load in the patient's stool.

C

Some viruses produce nucleocapsids with helical symmetry. Which of the following statements about helical nucleocapsids is most accurate? A.) All human viruses that produce helical nucleocapsids are members of a single virus family. B.) Most of the human viruses that produce helical nucleocapsids also have DNA genomes. C.) All human viruses that produce helical nucleocapsids also possess an envelope. D.) Helical nucleocapsids are more common than icosahedral nucleocapsids. E.) Only plant viruses (e.g., tobacco mosaic virus) synthesize virions that contain helical nucleocapsids.

A

Subacute sclerosing panencephalitis virus (SSPE) is best described by which of the following statements? A.) It is a progressive disease involving both white and gray matter. B.) It is a late CNS manifestation of mumps. C.) It occurs in approximately 1 per 100,000 cases of mumps. D.) Viral DNA can be demonstrated in brain cells. E.) Demyelination is characteristic.

C

The most sensitive test for the diagnosis of herpes simplex (HSV) meningitis in a newborn infant is to test for the presence of: A.) HSV-specific IgG antibody by Western blot. B.) HSV-specific IgM antibody by ELISA. C.) HSV DNA by polymerase chain reaction. D.) infectious virus capable of infecting cultured cells. E.) intracellular inclusion bodies in a Tzanck smear.

E

The presence of Negri inclusion bodies in host cells is characteristic of: A.) an infection caused by mumps virus. B.) infectious mononucleosis. C.) a congenital rubella virus infection. D.) aseptic meningitis. E.) a rabies virus infection.

E

The vaccine against measles is BEST CHARACTERIZED as: A.) a trivalent vaccine. B.) an inactivated vaccine. C.) a live-attenuated virus vaccine. D.) a recombinant protein-based vaccine. E.) A and C.

A

This vignette applies to the next 3 questions: A 56-year-old man developed symptoms consisting of headache, fatigue, general achiness and a distinct chill. Severe muscular aches ensued and his temperature rose to 103°F on the following day. Laryngitis, cough, and substernal soreness were noted. Physical examination revealed a slight tachycardia and slightly lower than normal blood pressure. The lymphoid follicles of the soft palate were enlarged and the nasal mucous membrane appeared bright red with areas of hemorrhage. The patient complained of loss of appetite and general weakness. What is the most common complication associated with his condition? A.) secondary pneumonia B.) otitis media C.) hepatitis D.) myocarditis E.) meningoencephalitis

B

This vignette applies to the next 3 questions: A 56-year-old man developed symptoms consisting of headache, fatigue, general achiness and a distinct chill. Severe muscular aches ensued and his temperature rose to 103°F on the following day. Laryngitis, cough, and substernal soreness were noted. Physical examination revealed a slight tachycardia and slightly lower than normal blood pressure. The lymphoid follicles of the soft palate were enlarged and the nasal mucous membrane appeared bright red with areas of hemorrhage. The patient complained of loss of appetite and general weakness. 16. What virus is the most likely cause of his condition? A.) rhinovirus B.) influenza virus C.) respiratory syncytial virus D.) parainfluenza virus E.) coronavirus

B

Traditional vaccination for the common cold is virtually impossible because there are multiple serotypes of which one of the following viruses? A.) rabies virus B.) rhinovirus C.) cytomegalovirus D.) respiratory syncytial virus E.) mumps virus

E

Which group of viruses causes a pathological change seen in epithelial cells termed koilocytosis? A.) herpesviruses B.) enteroviruses C.) arboviruses D.) polyomaviruses E.) papillomaviruses

E

Which is the most common etiological agent of viral diarrhea and gastroenteritis in infants? A.) adenoviruses B.) cytomegalovirus C.) Norwalk-like agents D.) arenaviruses E.) rotavirus

C

Which of the following BEST DESCRIBES a trait shared by hepatitis C virus and West Nile virus? A.) both are non-enveloped RNA viruses B.) both are routinely grown in cell culture C.) both belong to the same virus family D.) both are usually transmitted by blood E.) both routinely cause jaundice in patients

D

Which of the following best describes the presently available vaccine for hepatitis B? A.) a trivalent vaccine B.) an inactivated vaccine C.) a live-attenuated virus vaccine D.) a recombinant protein-based vaccine E.) A and C

B

Which of the following characteristics is true for the virus family that is the MOST COMMON cause of virus-induced diarrhea? A.) they are DNA viruses B.) their virions lack an envelope C.) their virions are sensitive to acidic pH D.) their virions are primarily transmitted in aerosol droplets E.) the incubation period between infection and disease onset is typically 3 weeks

E

Which of the following clinical manifestations are associated with advanced AIDS? A.) cytomegalovirus retinitis B.) Kaposi's sarcoma C.) loss of appetite and weight D.) neurological disorders E.) all of the above

B

Which of the following conditions is most likely to be associated with a parainfluenza virus infection? A.) transient aplastic crisis B.) bronchiolitis C.) coryza and cough in adults D.) otitis media E.) gingivostomatitis

C

Which of the following diseases might respond favorably to treatment with a reverse transcriptase inhibitor? A.) encephalitis caused by West Nile virus B.) encephalitis caused by herpes simplex virus C.) hepatitis caused by hepatitis B virus D.) poliomyelitis caused by poliovirus E.) pneuomonia caused by respiratory syncytial virus

D

Which of the following drugs has been shown to block uncoating of influenza A viruses? A.) acycloguanosine (acyclovir) B.) AZT (3'-azido-3'-deoxythymidine, zidovidine) C.) accutane D.) amantadine E.) zanamivur

C

Which of the following is a common cause of epidemic gastroenteritis, particularly aboard cruise ships and in summer camps? A.) rotavirus B.) adenovirus type 41 C.) Norwalk virus D.) astrovirus E.) hepatitis A virus

B

Which of the following is an enveloped RNA virus that may cause birth defects and is preventable by vaccination? A.) polio virus B.) rubella virus C.) hepatitis A virus D.) hepatitis C virus E.) cytomegalovirus

E

Which of the following is transmitted by the fecal-oral route, can be acquired from shellfish, and often causes acute jaundice, diarrhea, and liver function abnormalities? A.) rotavirus B.) adenovirus type 41 C.) Norwalk virus D.) Hendra-Nipah virus E.) hepatitis A virus

A

Which of the following protein markers is closely associated with the infectivity and DNA polymerase activity of hepatitis B virus? A.) HBeAg B.) HBsAg C.) HBcAg D.) anti-HBc E.) HBeAb

D

Which of the following statements about hepatitis A virus (HAV) is NOT correct? A.) HAV is related to poliovirus and may cause acute hepatitis. B.) Infectious hepatitis occurs predominantly in persons under 50 years old. C.) Infected persons may shed HAV for weeks before the onset of symptoms. D.) Health care workers who handle blood are at high risk for acute hepatitis. E.) Human immunoglobulin is used to prevent HAV infections during outbreaks.

B

Which of the following statements about hepatitis C virus infection is true? A.) It is caused by a naked, single-stranded RNA virus. B.) It is the most common cause of post-transfusion hepatitis. C.) It requires co-infection with hepatitis B virus to replicate. D.) Its pattern of transmission is similar to that of hepatitis A virus. E.) An effective vaccine is available.

E

Which of the following statements about measles virus and rubella virus is NOT TRUE? A.) Both viruses can cause an exanthem. B.) Both viruses have a single antigenic type. C.) Both viruses are transmitted by the aerosol respiratory route. D.) Both viruses can cause encephalitis. E.) Both viruses are teratogenic.

A

Which of the following statements about neonatal herpes and/or HSV-2 infection of pregnant mothers is FALSE? A.) Neonatal infection with HSV-2 usually occurs in utero by transplacental transmission. B.) Neonatal herpes is associated with severe neurologic morbidity of the newborn. C.) Mothers who acquire HSV-2 in the 3rd trimester are at higher risk for delivering a baby with neonatal herpes. D.) The risk of neonatal herpes is reduced when HSV-2 (+) mothers deliver their babies by Caesarian section. E.) The rate of birth defects does not increase when HSV-2 (+) mothers take acyclovir during pregnancy.

A

Which of the following statements about rabies is NOT true? A.) The majority of cases worldwide result from bat bites. B.) Infection may be prevented by active and passive immunization. C.) The rabies vaccine is based on formalin-inactivated virus. D.) The animal reservoir differs from country to country. E.) The disease may be diagnosed by serology.

A

Which of the following statements about recurrent genital herpes is TRUE? A.) People with genital herpes are at a greater risk for contracting HIV. B.) Oral acyclovir is not useful in reducing the severity of recurrent herpes outbreaks. C.) Anti-HSV IgG antibodies in a person's blood is proof that they have genital herpes. D.) Condoms offer complete protection against HSV-2 transmission from women to men. E.) None of the above.

A

Which of the following tests would BEST ALLOW you to differentiate whether or not an HIV-positive patient has AIDS? A.) CD4 lymphocyte count B.) ELISA for anti-HIV antibodies C.) RT-PCR for HIV RNA load D.) Western blot for anti-HIV antibodies E.) ELISA for HIV p24 antigen

B

Which of the following viral proteins is most directly associated with antiviral action of oseltamivir against influenza A and B viruses? A.) host cell DNA-dependent RNA polymerase B.) the viral neuraminidase C.) the viral hemagglutinin D.) the viral RNA polymerase E.) the M2 protein

C

Which of the following viral proteins is most directly associated with the antiviral action of amantadine and rimantadine against influenza A virus? A.) viral hemagglutinin B.) viral neuraminidase C.) viral M2 protein D.) host cell sialic acid E.) viral RNA-dependent RNA polymerase

C

Which of the following viruses has such a high incidence of genetic drift that multiple antigenic variants may be isolated from a single infected individual? A.) adenovirus type 5 B.) herpes simplex virus type 1 and type 2 C.) human immunodeficiency virus D.) influenza A virus E.) poliovirus

B

Which of the following viruses have segmented genomes? A: measles virus and influenza virus B: rotavirus and influenza virus C: Machupo virus and measles virus D: Norwalk virus and influenza virus E: measles virus and Lassa fever virus

C

Which of the following viruses is primarily transmitted by the fecal-oral route? A.) St. Louis encephalitis virus B.) Colorado tick fever virus C.) coxsackievirus D.) yellow fever virus E.) Dengue fever virus

A

Which of the following viruses would be the MOST LIKELY to be inhibited by an antiviral drug that inhibits a viral DNA polymerase? A.) cytomegalovirus B.) influenza virus C.) measles virus D.) mumps virus E.) rabies virus

C

Which of the following viruses would you expect to be MOST resistant to harsh environmental conditions? A.) human respiratory syncytial virus B.) human parainfluenza virus type I C.) poliovirus D.) influenza type A virus, H3N2 E.) measles virus

C

Which statement BEST EXPLAINS the selective action of acyclovir on DNA synthesis in herpes simplex virus-infected cells? A.) acyclovir blocks herpesvirus virions from attaching to host cells B.) acyclovir inhibits the RNA polymerase in the virion C.) viral thymidine kinase phosphorylates acyclovir more effectively than host kinases D.) acyclovir can only inhibit viral (not cellular) DNA polymerases E.) acyclovir inhibits the reverse transcriptase of herpes simplex viruses

B

Which statement about genital herpes is FALSE? A.) Asymptomatic carriers can transmit herpes simplex virus 2 (HSV-2) to a sexual partner. B.) Most HSV-2 infections cause 1 to 4 recurrences per year. C.) HSV-1 may cause genital herpes. D.) Crusted herpes lesions are a poor source of virus for culture tests. E.) None of the above.

E

Which statement about rhinoviruses is TRUE? A.) sensitive to low pH B.) initiate infection on mucosal surfaces C.) have distinct peaks of infection in the spring and fall D.) often spread via contact with viruses in nasal secretions on surfaces E.) all of the above