Viruses

Question 1

A patient comes in who has been travelling. Symptoms include tachycardia, diarrhoea, and you find they are confused and have been having fits.

What is the causative agent? Name the 4 main types of this agent? What are the drugs given for this agent? What are the three things required of you to do when someone comes in asking for advice when going abroad?

Answer 1

Malariaa
Falciparum, Ovale, Malariae, vivax
Falciparum: Doxycycline, Quinine, Artesutate
Others: Primaquine or chloroquine

Assess risk
Bite prevention
Chemoprophylaxis

Question 2

Person comes in with lymphadenopathy, pharyngitis, fever and on examination you find they have splenomegaly. Very sexually active with numerous sexual partners. You also find a lump in their jaw.

Causative agent? What is the name of the fever part of the infection? What is the name of the cancer? Explain how this agent causes the cancer (the mechanism of infection)? How would yyou identify this microbe in the lab?

Answer 2

Epstein barr virus
Infectious mononucleosis
Burkitt’s Lymphoma

Mechanism: Infects Oropharyngeal epithelium–>infecting B lymphocytes–>immortalisation and multiplication. This is what leads to the lymphoma

Lad identification: Atypical lymphocytes. Increased lymphocyte number (50-60% of the total leukocyte number). Increases in IgG, IgM and IgA

Question 3

Someone has come in from travelling with severe myalgia and headache. You send off the tests and it comes back positive for dengue

What type of virus is this? What is the incubation period of this virus? On the first infection, what are the symptoms and how do you treat it? On re infection, what is the danger?

Answer 3

arbo virus
<10 days
Symptoms of first infection: Non specific febrile infection that requires supportive treatment and goes away by itself

Second infection can cause haemorrhage and shock.

Question 4

A group of 20 people have come in on the same day complaining of diarrhoea, vomiting and nausea. All 20 went to the same party.
What is the causative agent? What is the mechanism of transmission of this? Complication? What is the name of the condition described? How would you prevent this infection?
Describe the prevention in terms of the 4Ps of infection prevention.

Answer 4

Norovirus
Faecal oral route
Complication- Dehydration
The condition is Epidemic Acute gastroenteritis
P-pathogen- Very infectious
P-Patient- Need to be isolated
P-Place- Needs to be sterilised
P-Practice- Hand wahsing and food preparation needs to be up to scratch

Question 5

A child comes in with a fever and a vesicular rash.

Causative agent? What is the common name of this infection? How is this organism transmitted? What is the approximate incubation period of this organism?
The child clears the rash. Has the virus completely goone? If no, where is the virus and what is this period called? If this virus comes back as an adult, what is the infection called? What is the treatment of this?

Answer 5

Varicella Zoster.
Chicken pox
transmitted by respiratory droplets
14-21 days
no, this is lying in its latent phase in multiple sensory ganglion

As an adult, called shingles (Herpes Zoster)
Note only affects one dermatomal area because it is from one sensory ganglion
treatment is Acyclovir

Question 6

Symptoms: immunosuppressed patient- Coughing up sputum, lung infection
What’s the causative agent? What type of microbe is this? What is the complication of this lung infectioN? What is the name of the treatment?
What other sort of patient can this infect?

Answer 6

Aspergillus
A fungi
Can disseminate to other tissue eg brain, GI. Can be fatal
Treatment: Amphotericin 
Patients with a lung problem

Question 7

A patient comes in with raised white plaques on the oral mucosa, tongue and gums

what is the causative agent? What type of microbe is this? Where is this normally found? What other infection can it cause? Symptoms of this other infection? What is the treatment for this infection?

Answer 7

Candida Albicans
Fungus
Normally found on the vagina, mouth and skin
Can develop vaginal candidiasis
symptoms for this: Ithcing and burning pain of vulva and vagina with a white discharge

Treatment- Azoles (eg Fluconazole)

Question 8

History: A lady comes in who has been on her gap year. Went to Malawi and whilst there was swimming in a lake. After swimming she noticed a rash on her leg; overtime this became more pronounced and generalised

After 3 weeks, she started to get a fever, lethargy, and had general body ache

what is the causative agent? What type of microbe is this?What four things would a full blood count reveal? One examination what would you find? What is the treatment of this? Complications?

Answer 8

Schistomiasis
It’s a helminth
Raised WBC count, Raised CRP, Raised Neutrophil count, Raised EOSINOPHIL count
Hepatosplenomegaly
Treatment is antiparasitic medication. No need for hospital admission

Complications: Fibrosis of the liver bowel and bladder

Question 9

Describe the process of infection of schistomiasis

Answer 9

Penetrates the intact skin of the swimmer
You get a localised reaction at the site of entry
If left untreat, can enter bladder and bowel and lay eggs causing an immunological reaction and fibrosis of liver, bladder and bowel

Question 10

Symptoms: Cough, sore throat, congested nose, fever
some people have conjuntivitis
What virus is this? Where does this virus replicate?

Answer 10

Adenovirus

in epithelial cells