Question 1 - Single Best Answer
You are asked to give advise to a group of archeologists who will spend a year exploring ruins in a remote area of Mexico where indoor plumbing is non-existent. You will advise
they get immune serum globulin to prevent Hepatitis E they get Hepatitis A vaccine they get Hepatitis B vaccine they get Hepatitis C vaccine all the above
Question 2 - Single Best Answer
A 6-month-old baby boy was brought to your office in December because of fever, rhinorrhea, and a harsh, "barking" cough. The cough did not produce any sputum. The child's mother said that the baby's appetite was "o.k." and that he had not been vomiting. The mother also said that this was the first time the baby had ever been sick. Examination revealed a slightly red throat and prominent upper airway sounds. There were no crackles or subcostal retractions, but there was persistent stridor during inspiration. The virus causing this disease
can cause three types of neurological complications has a genome composed of seven RNA fragments has been engineered and made into an efficacious vaccine can be effectively treated with antiviral medication
Question 3 - Single Best Answer
For rabies virus infection of humans:
Virus is transmitted by insect bites The human vaccine is a live, attenuated virus The virus is carried in the blood and passes the blood/brain barrier to infect the brain It is possible to protect an individual by vaccination after exposure to the virus because of its long incubation period The vaccination protocol involves administering only the vaccine
Question 4 - Single Best Answer
Which of the following viruses would be most resistant to drying in the environment?
an adenovirus a herpesvirus, such as herpes simplex type I a retrovirus, such as HIV a paramyxovirus, such as measles a flavivirus, such as hepatitis C a hepadnavirus, such as hepatitis B
Question 5 - Single Best Answer
A 55 year old male presents with fever, a stiff neck and confusion. You suspect meningitis and perform a spinal puncture which reveals the presence of WBCs (mostly mononuclear cells) but normal glucose levels. A family history reveals the patient's granddaughter who recently visited had herpangina. A positive viral culture from the CSF confirms your suspicion that the meningitis was caused by:
group B streptococcus coxsackievirus poliovirus human herpes virus 6 west nile virus
Question 6 - Single Best Answer
Although enveloped viruses are generally more unstable in the environment they are thought to have a pathogenic advantage in that
they induce less interferon because they do not have a double-stranded RNA intermediate antibody has more targets on a naked virus whose coat is composed of only protein than on an enveloped virus cell mediated immunity is not induced against enveloped viruses enveloped viruses can go directly from cell to cell and are therefore less susceptible than naked viruses to host defenses enveloped viruses do not induce an antibody response due to the lipid in the envelope which inhibits contact with B cells
Question 7 - Single Best Answer
Choose the most correct statement about antiviral drugs
antiviral drugs are directed solely against enzymes and proteins associated with the replication nucleic acid one justification for the use several rather than one antiviral agent is related to concerns about development of drug resistance generally, resistance to an antiviral agent is associated with a precise single mutation in a single protein target the preponderance of antiviral drugs on the market today are those targeted towards herpesviruses and the hepatitis viruses
Question 8 - Single Best Answer
Which of the following viruses is LEAST likely to contain a nucleic acid polymerase in the virion?
a reverse transcribing virus such as HIV or hepatitis B a reovirus, such as rotavirus a picorna virus, such as polio an orthomyxovirus, such as influenza a rhabdovirus, such as rabies
Question 9 - Single Best Answer
Which of the following is not a means of acquiring a hantavirus infection?
aerosol route from rodent urine direct exposure to rodent feces person to person contact sweeping out a shed in an area where hantavirus is prevalent
Question 10 - Single Best Answer
A 19 year old U of F college student is seen in the student infirmary with nausea, diarrhea, mild fever, and dark urine. You would order the following laboratory tests:
alanine aminotransferase (ALT) hepatitis B surface antigen hepatitis B core IgM antibody hepatitis A IgM antibody all the above
Question 11 - Single Best Answer
The reservoir for measles virus has been found to be
birds seals dogs humans humans and great apes
Question 12 - Single Best Answer
Which of the following statements is TRUE of an HBV infection?
Antibody to HBsAg indicates a chronic infection The presence of HBcAg indicates a recovered infection The presence of HBsAg and the absence of antibody to HBsAg indicates a chronic infection 90% of infections result in chronic infection 50% of infections result in hepatocellular carcinoma
Question 13 - Single Best Answer
Influenza hemagglutinin molecules within the same subtype
are all found on only one species of animal are all equally crossreactive in serological tests may differ significantly in their ability to bind sialic acid are always associated with the same neuraminidase subtype are all at least 90% homologous at the amino acid level
Question 14 - Single Best Answer
Live vaccines have the potential to mutate or recombine with wild-type viruses to revert to a virulent form. For which of the following vaccines would this type of reversion NOT occur?
Sabin polio vaccine (OPV) varicella vaccine Hepatitis B vaccine measles vaccine
Question 15 - Single Best Answer
Rubella
is spread by an insect vector causes a severe disease in children is dangerous because it can have teratogenic effects (effects on a developing fetus) is prevented by a killed viral vaccine; the killed vaccine is used because a live virus vaccine was found to harm unborn children
Question 16 - Single Best Answer
If you were vaccinating for a disease prevalent in rural Sub-Saharan Africa which of the following vaccines would you predict to be most effective considering the locale.
Measles vaccine Hepatitis B vaccine Sabin polio vaccine Rubella vaccine Varicella-zoster
Question 17 - Single Best Answer
The "eclipse" phase of virus growth results from
clearance of infectious virus by the immune system uncoating of infecting virus particles early during infection shut off of host protein synthesis attachment of virus to the cell surface cell lysis
Question 18 - Single Best Answer
A 25 year old pregnant female presents with jaundice. She returned a month ago from a trip to India. You suspect viral hepatitis as a possible cause and order a serological tests. Because of her condition, which of the following would pose the greatest risk:
Hepatitis A Hepatitis B Hepatitis C Hepatitis D Hepatitis E
Question 19 - Single Best Answer
The first step in making new proteins for positive strand RNA viruses is
making double stranded RNA making double stranded DNA binding the injected RNA to the ribosomes making negative strand RNA entering the nucleus to utilize the host's RNA polymerase
Question 20 - Single Best Answer
A population of mouse cells in culture is infected with a mouse retrovirus at a high multiplicity of infection. Among the infected cells only about 1 cell in 10 million cells exhibits characteristics of a transformed cell. Which of the following is the most likely mechanism for the viral transformation of the mouse cells in this case?
insertional activation of a cellular proto-oncogene expression of a viral oncogene cellular mutation by insertion of the virus within the coding sequence of an essential cellular gene stimulation of cellular replication by a viral replication gene
Question 21 - Single Best Answer
A common feature of cervical carcinomas is that they contain integrated papillomavirus DNA. Which of the following statements best describes the common feature of these integrated viral genomes?
They are all integrated into the same place on human chromosome 19. The E1 gene, responsible for viral DNA replication, is disrupted. The E2 gene, responsible for regulation of viral transcription, is disrupted. The E6 gene, responsible for degradation of cellular p53, is disrupted. The E7 gene, responsible for binding the cellular Rb protein, is disrupted. No. This could happen, but it would not cause a carcinoma.
Question 22 - Single Best Answer
Prions are infectious entities that can reproduce by:
a (-) stranded RNA template a virally encoded polypeptide catalyzing the refolding of homologous peptides triplet repeat expansion within the gene encoding the protein
Question 23 - Single Best Answer
Neonatal encephalitis is a danger to babies born of mothers with
rubella measles Eastern Equine Encephalitis HSV I HSV II
Question 24 - Single Best Answer
The most serious complication of measles is:
pneumonia encephalitis cardiomegaly epilepsy deafness
Question 25 - Single Best Answer
Which of the following is NOT a disease associated with adenovirus infection?
acute respiratory disease conjunctivitis gastroenteritis hemorrhagic cystitis erythema infectiosum or fifth disease.
Question 26 - Single Best Answer
A 10 year old male presents with a mild fever and respiratory symptoms, and severe bilateral conjunctivitis. Which of the following viruses would you least likely suspect as the cause:
adenovirus enterovirus echovirus coxsackievirus
Question 27 - Single Best Answer
Influenza vaccine strains used each year in the US are
the same every year based on isolation of virus from birds in China based on isolation of virus from pigs in China based on the strains circulating in South America prior to the flu season in the US. based on the first cases of flu in the US
Question 28 - Single Best Answer
Differential diagnosis between smallpox and chicken pox include:
smallpox lesions develop differently with time, whereas chicken pox lesions have a synchronous, similar times of development smallpox lesions tend to be more extensive at the extremities whereas those of chickenpox tend to concentrate on the trunk fever in chickenpox precedes onset of rash, whereas in smallpox fever occurs simultaneously with rash development chickenpox lesions are common on the hands and feet, whereas in smallpox, lesions on the hands and feet are relatively rare.
Question 29 - Single Best Answer
Cytopathic effect
is caused by all viruses is caused only by naked capsid viruses is caused only by enveloped viruses invariably includes cell lysis can sometimes help in the identification of the type of virus in cell culture
Question 30 - Single Best Answer
The human parvovirus B19
is transmitted as a zoonosis from dogs. causes widespread infections, most of which are asymptomatic replicates only in non-dividing cells. encodes its own DNA polymerase. infection can be prevented by use of an inactivated virus vaccine.
Question 31 - Single Best Answer
The human polyomavirus BK
is transmitted by the fecal oral route causes acute nephritis in most infected people, and then is cleared. can cause hemorrhagic cystitis in immunosuppressed people. encodes its own DNA polymerase. integrates its DNA into the host chromosome to establish latency.
Question 32 - Single Best Answer
Who discovered that rabies could be prevented by post-exposure vaccination?
Salk Sabin Jenner Koch Pasteur
Question 33 - Single Best Answer
A 10-year-old boy was sent home from school due to pain on both sides of the parotid area while eating lunch. The swelling of the glands increased in 2 to 3 days while he remained home. He complained of a headache and had a low-grade fever. This child had not received all the required vaccinations. The teacher reported that one of the other students in the classroom had similar complaints three weeks earlier. The initial replication with this virus takes place in the:
villi of the small intestine colonic mucosa brain meninges upper respiratory tract parotid gland
Question 34 - Single Best Answer
In the context of virus infections, a "prodrome" is defined as
an initial incubation period following infection that produces nonspecific early symptoms. the innate immune response to a virus infection an asymptomatic early phase of a virus infection. the first stages of the adaptive immune response to a virus infection. the emergence of disease symptoms at secondary sites of virus infection.
Question 35 - Single Best Answer
Which of the following does not represent an accurate transmission cycle for West Nile Virus?
bird --> mosquito --> man bird --> mosquito --> bird --> mosquito --> horse bird --> mosquito --> horse --> mosquito --> bird bird --> mosquito --> horse mosquito --> bird --> mosquito
Question 36 - Single Best Answer
A young women at the University of Florida, about a month after her first sexual encounter, came to the infirmary complaining of 4-day history of fever, chills, and myalgia. Two days prior to this, she had noted some blisters on her vagina that were very painful. She also had developed a severe headache and a stiff neck. All of these symptoms were still present. Loud noises and bright lights bothered her, but she could still go about most of her daily activities. Her doctor recommended which of the following therapies?
ribivarin interferon acyclovir aspirin and bed rest penicillin
Question 37 - Single Best Answer
Paul is infected with HIV and in fact has AIDS. His CD4 cell count was less than 200 cells/mm3 but after treatment with HAART he is doing much better. What clinical picture is most likely after 5 months on HAART?
his viral load is undetectable and his CD4 cell counts are 400 cells/ mm3 his viral load is high and his CD4 cell counts are 400 cells/ mm3 he has begun to clear HIV from the reservoirs of sequestered cells and may eventually eliminate the virus from his system there has been no change in either his viral load or CD4 cell count
Question 38 - Single Best Answer
A common factor facilitating the re-emergence in the 1990s of measles in the US was?
an increased immunocompromised population inadequate immunization increased injection of drugs microbial adaptation the spread of HIV infection
Question 39 - Single Best Answer
A "fomite" is defined as
any agent that is capable of inactivating microbes, for example bleach. an insect vector that carries a microbial infection from an animal, for example birds, to humans. an intermediate animal host capable of transmitting microbes from a non human reservoir to humans, for example swine, which may serve as an intermediate host for transmission of influenza from birds to humans. any object which can be contaminated with microbes and therefore serve to transmit microbes from one person to another, for example a handkerchief or a toy. an antimicrobial agent that specifically inhibits nucleic acid replication.
Question 40 - Single Best Answer
Determination of the papillomavirus type present in an infection is best done
by culturing the virus serology cytological examination of infected tissue. assay of infected tissue for papillomavirus DNA polymerase assay for viral DNA.
Question 41 - Single Best Answer
A lingering concern over the varicella zoster vaccine is that the vaccine:
has a high mortality rate may increase the incidence of shingles is associated with Reyes syndrome is not effective in adults does not reduce the incidence of chickenpox
Question 42 - Single Best Answer
Parainfluenza and respiratory syncitial viruses differ from measles virus in that
they initially infect the respiratory tract they have segmented RNA genomes they don't cause a viremia they can infect animals
Question 43 - Single Best Answer
A medical student at USF called his mother, a microbiologist, complaining of a fever, headache, and inability to swallow. She drove from Gainesville with some chicken soup and found him in bed, dehydrated and somewhat feverish. When he opened his mouth she could see that his throat was very red and that his tonsils almost touched at midline. She thought he had a virus infection and that chicken soup would cure him, but just to be safe she swabbed his throat for later growth in her laboratory on blood agar. The virus she thought he had also can cause
neonatal encephalitis nasopharyngeal carcinoma croup labial cold sores Koplick spots
Question 44 - Single Best Answer
Which of the following procedures inactivate(s) prions?
Boiling in water Filters used for removing bacterial pathogens X-irradiation doses suitable for inactivating most viruses All of the above None of the above
Question 45 - Single Best Answer
Which of the following vaccines protects against hepatitis D virus induced disease? A vaccine against:
Hepatitis A Hepatitis B Hepatitis C HIV None of the above
Question 46 - Single Best Answer
Which of the following is NOT a factor contributing to the occurrence of major pandemics of influenza A virus?
a major reservoir for influenza viruses is birds influenza has a segmented genome different influenza hemagglutinin subtypes are not serologically crossreactive reassortment of influenza genome segments can take place in intermediate species, for example pigs. small changes in amino acid sequence within immunodominant epitopes within a given influenza hemagglutinin subtype can alter the immunological reactivity of the hemagglutinin.
Question 47 - Single Best Answer
The MMR vaccine is given at about 15 months of age, as opposed to DTP (Diphtheria, Tetanus, Pertussis) which is given starting at about 2 months of age. The reason for this is
measles, mumps and rubella are not a problem in babies until they are over a year old the rubella portion of the vaccine can cause teratogenic effects in young babies the maternal antibodies to measles will inactivate the vaccine virus the cellular immune system is not active until after 15 months of age
Question 48 - Single Best Answer
HIV infection causes:
cellular proliferation due to the presence of an oncogene lymphocyte proliferation induced by activation of cellular protooncogenes slow and persistent destruction of lymphocytes a completely asymptomatic disease prior to onset of terminal symptoms purple skin lesions referred to as Kaposi's sarcoma
Question 49 - Single Best Answer
Which statement regarding measles, mumps, parainfluenza viruses and respiratory syncytial virus (RSV) is true
each of these viruses causes a general disseminated infection mumps infections are characterized by extensive rashes all paramyxovirus infections are characterized by a high percent of non-apparent infections vaccines are available for measles, mumps and RSV neurological complications are the most serious concern with measles virus but are of little concern with mumps virus
Question 50 - Single Best Answer
A direct electron microscope count of a preparation of influenza virus reveals 1010 particles per ml of virus solution. A plaque assay of the same preparation reveals a titer of 108 plaque forming units (pfu) per ml of virus solution. A hemagglutination assay of the same preparation reveals an HA titer of 103 HA units per ml of virus solution. Considering these observations, which of the following statements is true?
Only one in 107 of the influenza virus particles in this preparation is infectious. Only one in 100 of the influenza virus particles in this preparation is infectious. A minimum of 107 virus particles are required to observe one unit of hemagglutination. Each erythrocyte in the hemagglutination assay binds 107 virus particles. The electron microscope is broken.
Question 51 - Single Best Answer
Assembly of mature infectious papilloma virus particles
occurs only after viral DNA integration into host cell DNA. requires active cell division. occurs only in cells co-infected with adenovirus. normally occurs only in immunosuppressed people. occurs only in non-dividing, upper spinous layers of the epithelium
Question 52 - Single Best Answer
Influenza virus (NOTE: This question was discarded as there was apparently some confusion that caused many people to miss it the best answer, and one that everyone SHOULD have chosen, is,however, C.)
enters cells via fusion directly with the plasma membrane replicates its genome in the cell cytoplasm packages an RNA dependent RNA polymerase in the virion directs synthesis a single protein from each of its RNA segments all of the above
Question 53 - Single Best Answer
A 27 year old white male college student who had been raised in a religious community that prohibited vaccination developed a very painful swelling of his testicles a week to ten days after he had had a sore throat and fever. One side of his face was also somewhat swollen. The disease causing his problem was almost certainly transmitted to him by
sexual activity respiratory route saliva (kissing) fecal-oral route endogenous route
Question 54 - Single Best Answer
To which of the following will a person develop antibody after successful immunization against hepatitis B virus?
HBcAg HBeAg HBsAg All of the above None of the above
Question 55 - Single Best Answer
A hemagglutination inhibition test is used to measure
virus particles in serum virus infected erythrocytes infectious virus in serum antiviral antibodies in serum none of the above
Question 56 - Single Best Answer
Which of the following viruses does NOT cause a viremia during the course of a normal infection?
varicella zoster virus influenza virus measles virus polyomavirus hepatitis A virus
Question 57 - Single Best Answer
A 32 year old female is diagnosed with Dengue-shock syndrome. Which of the following situations is associated with increased risk for this syndrome?
hypertension prior infection with a different serotype of Dengue acquiring the infection during the first trimester of pregnancy co-infection with HIV
Question 58 - Single Best Answer
Most of the herpesviruses are spread by direct person-person contact. Which of the herpesviruses below can also be spread by the airborne route?
HSV-1 EBV CMV VZV HHV8
Question 59 - Single Best Answer
Vaccines are currently available for which of the following hepatitis viruses?
HBV HAV and HBV HAV and HEV HBV, HCV and HDV HBV, HDV and HEV
Question 60 - Single Best Answer
Which of the following is an example of an equilibrium human virus?
influenza ebola varicella hantavirus HIV
Question 61 - Single Best Answer
A virus that can cause an aplastic crisis in sickle cell anemics also causes
a respiratory disease a rash in children lymphoma hepatitis
Question 62 - Single Best Answer
New and effective antiviral compounds are in development and many have been in use for about a decade. One such compound is ribavirin, a synthetic nucleoside structurally related to guanosine. Ribavirin therapy has been most successfully used against?
parvovirus rhinovirus herpes simplex virus respiratory syncytial virus group A coxsackie virus
Question 63 - Single Best Answer
Which of the following statements is TRUE of a rotavirus infection?
The virus has a long incubation period A licensed vaccine is currently available The virus replicates primarily in the gastrointestinal tract The virus is spread by respiratory secretions Infections are rarely asymptomatic
Question 64 - Single Best Answer
During a chronic infection
an infected person may shed virus even in the absence of symptoms no virus is detectable in the infected person. an infected person invariably displays symptoms of clinical disease. the viral genome must become integrated into the host chromosome in order to maintain the viral genome over a long period of time. individual infections are cleared but a person is continuously reinfected.
Question 65 - Single Best Answer
Papillomaviruses are normally transmitted by
direct contact, including sexual contact the fecal-oral route blood transfusion or organ transplant insect vectors animal bites
Question 66 - Single Best Answer
When considering an infectious agent for eradication which conditions are the most optimal
three serotypes, infections limited to humans, few inapparent infections and natural infections produce long term immunity a single serotype, infections limited to humans, few inapparent infections, natural infections produce short term immunity a single serotype, infections limited to squirrels and humans, long term immunity a single serotype, infections limited to humans, many infections are inapparent and natural infections produce long-term immunity
Question 67 - Single Best Answer
Which of the following viruses naked genomes would NOT be infectious if introduced into a cell? (This question had two right answers)
rhinovirus yellow fever virus ebola virus poliovirus *vaccinia virus
Question 68 - Single Best Answer
The Alphavirus genomic RNA contains a "stop codon" just past the halfway point on the genome. This stop codon:
terminates transcription of the (-) strand RNA template terminates transcription of the (+) strand RNA genome copy terminates translation of the non-structural polyprotein initiates transcription of the sub-genomic RNA
Question 69 - Single Best Answer
In addition to Rubella, which of the following poses a risk of the offspring having mental retardation and microcephaly if the mother acquires the primary infection during pregnancy?
varicella zoster cytomegalovirus hepatitis A virus coxsackievirus Epstein barr virus
Question 70 - Single Best Answer
A 65 year old woman presents with a painful, vesicular lesion over her left eye. The region covers several centimeters and has very defined borders. You diagnose the syndrome as shingles or herpes zoster, and know that this resulted from a reactivation of latent virus from the:
trigeminal ganglion cervical ganglion monocytes keratinocytes dendritic cells
Question 71 - Single Best Answer
Which of the following groups of hepatitis viruses all pose a significant risk of cirrhosis?
HAV and HBV HAV and HEV HBV, HCV and HDV HBV, HDV and HEV
Question 72 - Single Best Answer
The adenovirus vaccine used against adenovirus serotypes 4 and 7
consists of live wild type virus taken orally as an enteric capsule. is a killed vaccine is a live attenuated vaccine is a subunit vaccine make by expression of viral capsid proteins in yeast. is used routinely to prevent adenovirus infections in children