6th MICROBIOLOGY LONG LECTURE EXAM

TRUE about management of hepatitis C infection.

1- treatment duration is usually 24-48 weeks depending on the presence of hepatocellular carcinoma [12-24]

2- acute infection is usually not treated since it will resolve on its own in 80%

3- liver damage can be assessed through APRI

scoring and liver biopsy in resource limited settings[FIB4]

4- treatment can be started as early as 12 years old and above

• A. 1,2,3

• B. 1 AND 3

• C. 2 AND 4

• D. 4 ONLY

• E. None of the choices above

All of the following statement/s is/are TRUE about Yellow fever :

1- it is one of the first diseases identified among the flaviviruses

2- it causes death up to 90% during the first 7 days of infection

3- It primarily infects liver and biliary system thus causing jaundice and bleeding

4- The vaccine is very effective in preventing the resurgence of yellow fever infection

• A. 1,2,3

• B. 1 AND 3

• C. 2 AND 4

• D. 4 ONLY

• E. None of the above choices

Answer explanation

2- it causes death up to 90% during the first 7 days of infection [5-50% mortality rate]

3- It primarily infects liver and biliary system thus causing jaundice and bleeding [liver cells only]

E. None of the above choices [1,4]

A 77 year old patient diagnosed diabetic with cancer on chemotherapy seek consult due to 5 days history of cough associated with fever and difficulty breathing. What is the best diagnostic test to consider possible COVID-19 infection in this patient?

• A. antigen test using nasopharyngeal swab

• B. saliva for RT PCR testing

• C. nasopharyngeal swab for RT PCR

• D. rapid antigen test done at the clinic using blood

• E. antibody testing using serum since it has a faster turn -around time and cheaper

Answer explanation

C. nasopharyngeal swab for RT PCR (Agree since chemotherapy therefore low Ab response)

TRUE about neuraminidase glycoprotein of influenza viruses EXCEPT:

1-it facilitates release of mature virions from the infected cells

2- assists in viral movement through the mucus to adjacent cells

3- they are mushroom shaped spikes

4- facilitate attachment to cell receptors

• A. 1,2,3

• B. 1 AND 3

• C. 2 AND 4

• D. 4 ONLY

• E. None of the above choices

Answer explanation

4- facilitate attachment to cell receptors -hemagglutinin

They are double stranded, nonenveloped RNA virus with segmented RNA genome.

• A. Retroviruses

• B. Polioviruses

• C. Picornaviruses

• D. Reoviruses

• E. All of the above

TRUE about Dengue virus EXCEPT:

1- it is the most prevalent arthropod borne disease in the world

2- subsequent infection will result in immune enhanced disease such as dengue shock syndrome

3- infecting serotypes confer immunity to the other serotypes

4- a vaccine is already available

• A. 1,2,3

• B. 1 AND 3

• C. 2 AND 4

• D. 4 ONLY

• E. None of the above choices

Answer explanation

E. None of the above choices [3 only]

Which of the following statements is NOT TRUE about antigen tests for COVID-19 infection?

• A. They are best used in asymptomatic patients who are exposed to COVID-19 positive patients since they have high sensitivity and specificity

• B. They are expensive and can be used at the point of care such as clinics.

• C. They detect specific viral antigens present in the blood

• D. nasopharyngeal and nasal swabs can be used as specimens

• E. All of the above

Answer explanation

A. They are best used in asymptomatic patients who are exposed to COVID-19 positive patients since they have high sensitivity and specificity [persons with high viral load; moderate sensitivity]

When was Zika virus infection confirmed?

• A. February 2012

• B. May 2015

• C. December 2019

• D. September 2009

• E. January 2017

Answer explanation

A. February 2012 [MERS-CoV]

B. May 2015 [Zika]

C. December 2019 [SARS-

CoV-2]

E. January 2017 ?others; Nov 2002 [SARS-CoV], not sept. 2009 [H1N1]

The most common human viral infections are dueto:

• A. Retroviruses

• B. Rhinoviruses

• C. Flaviruses

• D. Enteroviruses

• E. A and C only

TRUE about Arenaviruses.

• A. They are non-envelope spherical viruses with Tshape glycoprotein spikes

• B. They readily infect mammals including humans,rodents and bats

• C. Infection of humans is through direct contact with animals and inhalation of rodent secretions thru aerosols

• D. Viral culture can be done routinely especially if antibody detection is delayed for several days

• E. All of the above

Answer explanation

Anwer is in blue

A. They are non-envelope spherical viruses with Tshape glycoprotein spikes - enveloped

B. They readily infect mammals including humans,rodents and bats [i think this bc only via rodents ang transmission?

C. Infection of humans is through direct contact with animals and inhalation of rodent secretions thru aerosols [rodents specifically?]

D. Viral culture can be done routinely especially if antibody detection is delayed for several days - not routinely recommended