Viruses

Question 1

Issue with viruses?

Answer 1

Viruses can’t be seen or grown easily - not visible with light microscope and can only reproduce in live cells. Can do in lab but takes 2-4 weeks

Question 2

what is serology

Answer 2

the study of / detection of antibody responses in the serum

Question 3

Serology - IgM

Answer 3

IgM appears within 1 week of infection for up to 12 weeks

Question 4

Serology - IgG

Answer 4

IgG remains for life. Can also be used for bacteria that is harder to culture

Question 5

Methods of serology (5)

Answer 5

1 Complement fixation test
2 Haemagluttination
3 ELISA - enzyme linked immunosorbent assay
4 Radioimmunoassay
5 Immunofluorescence  
Can take a couple of days

Question 6

3 diagnosis methods for viruses

Answer 6

serology
virus culture
virus detection

Question 7

what is virus detection

Answer 7

detection of viral antigens in a virus

Question 8

methods of virus detection

Answer 8

• electron microscopy
• ELISA
• IF
• Latex agglutination
• Molecular diagnostic tests (PCR ligase chain reaction)

Question 9

how does PCR work?

Answer 9

• it looks at the presence of viral nucleic acid in a tissue sample, blood or swab
• diff enzymes unzip chains of nucleic DNA / RNA and make complimentary copies using nucleoside bases as substrate

Question 10

advantages of PCR

Answer 10

very sensitive and quick

Question 11

disads of PCR

Answer 11

so sensitive it could pick up a contamination and give a false positive result
PCR only detects nucleic material complimentary to the primer sequences used so you need to suspect something to look for it

Question 12

Virus: Varicella Zoster
Diagnosis: ?
Test: ?
Other info: ?

Answer 12

Virus: Varicella Zoster
Diagnosis: Chicken pox
Test: ELISA - IgM for virus
Other info: found in kids, vesicular rash - calamine lotion

Question 13

Virus: Herpes zoster
Diagnosis: ?
Other info incl treatment

Answer 13

Virus: Herpes zoster
Diagnosis: Shingles
Other info: Reactive latent virus, give aciclovir

Question 14

Virus: HIV
Diagnosis: ?
Test: ?
Other info: ?

Answer 14

Virus: HIV
Diagnosis: AIDs
Test: Western blot line assay (+ve coloured band)
Other info: Chronic infections

Question 15

Virus: Hepatitis B
Diagnosis: ?
Test: ?
Other info: ?

Answer 15

Virus: Hepatitis B
Diagnosis: hepatitis
Test: ELISA - surface antigen
Other info: Chronic infections

Question 16

Virus: Human cytomeglayvirus (herpes)
Diagnosis: ?
Other info: ?

Answer 16

Virus: Human cytomeglayvirus (herpes)
Diagnosis: diarrhoea
Other info: in immunosuppressed pts

Question 17

Virus: Hep A
Diagnosis: ?
Test: ?
Other info: ?

Answer 17

Virus: Hep A
Diagnosis: hep A - jaundice
Test: ELISA - positive IgM
Other info: Shellfish / been on holiday

Question 18

Virus: Parrovirus (eyrthrovirus)
Diagnosis: ?
Test: ?
Other info: ?

Answer 18

Virus: Parrovirus (eyrthrovirus)
Diagnosis: erythema infectosium (fifth disease)
Test: ELISA test - IgM parrovirus (+ve = yellow)
Other info: slapped cheek in babies, via clotted blood collection

Question 19

Virus: Enterovirus
Diagnosis: ?
Test: ?
Other info: ?

Answer 19

Virus: Enterovirus
Diagnosis: viral cause of meningitis
Test: enterovirus culture on CSF
Other info: slow onset meningism e.g. Rhinovirus

Question 20

Virus: Resp synctial virus
Diagnosis: ?
Test: ?
Other info: ?

Answer 20

Virus: Resp synctial virus
Diagnosis: bronchiolitis in infants
Test: monoclonal antibody (green = +ve)
Other info: baby with wheeze

Question 21

Virus: legionella pneumonia
Diagnosis: ?
Test: ?
Other info: ?

Answer 21

Virus: legionella pneumonia
Diagnosis: legionairres disease (fever, cough, myalgia)
Test: ELISA
Other info: Holiday to spain / air con

Question 22

Virus: Epstein-Barr virus
Diagnosis: ?
Test: ?
Other info: ?

Answer 22

Virus: Epstein-Barr virus
Diagnosis: Glandular fever
Test: Immunofluorescent anti-IgG (yellow = +ve)
Other info: student, sore throat, fatigue

Question 23

Virus: Parainfluenza
Diagnosis: ?
Other info: ?

Answer 23

Virus: Parainfluenza
Diagnosis: Croup (bronchiolitis)
Other info: Stridor, barking cough

Question 24

Virus: Mumps
Diagnosis: ?
Other info: ?

Answer 24

Virus: Mumps
Diagnosis: Mumps - headache, malaise, fever
Other info: MMR vaccine

Question 25

Virus: Rubella Diagnosis: ? Other info: ?

Answer 25

Virus: Rubella Diagnosis: German measles - rash and lymphadenopathy, splenomegaly Other info: MMR vaccine

Question 26

what is stridor

Answer 26

a harsh vibrating noise when breathing, caused by obstruction of the windpipe or larynx.

Question 27

ALT / AST?

Answer 27

The AST/ALT ratio is the ratio between the concentrations of the enzymes aspartate transaminase (AST) and alanine transaminase (ALT) in the blood, useful in medical diagnosis to differentiate between causes of liver damage, or hepatotoxicity.

Question 28

What rises in hepatitis?

Answer 28

ALT and AST

Question 29

``` Virus: Hepatitis A Incubation period: ? Transmission: ? Acute disease: ? Chronic disease: ? ```

Answer 29

``` Virus: Hepatitis A Incubation period: 2-6 wks Transmission: Faecal-oral Acute disease: Rarely fulminant (severe and sudden in onset) Chronic disease: does not occur ```

Question 30

``` Virus: Hepatitis B Incubation period: ? Transmission: ? Acute disease: ? Chronic disease: ? ```

Answer 30

Virus: Hepatitis B Incubation period: 2-6mo Transmission: Parenteral, sexual, vertical Acute disease: 5% fulminant Chronic disease: Chronic hepatitis, cirrhosis, hepatoma

Question 31

``` Virus: Hepatitis C Incubation period: ? Transmission: ? Acute disease: ? Chronic disease: ? ```

Answer 31

``` Virus: Hepatitis C Incubation period: 6-12 wks Transmission: Parenteral Acute disease: Rarely fulminant Chronic disease: Chronic hepatitis, cirrhosis, hepatoma ```

Question 32

``` Virus: Hepatitis E Incubation period: ? Transmission: ? Acute disease: ? Chronic disease: ? ```

Answer 32

``` Virus: Hepatitis E Incubation period: 2-9 wks Transmission: Facael-oral Acute disease: Rarely fulminant except in pregnancy Chronic disease: Does not occur ```

Question 33

``` Virus: CMV Incubation period: ? Transmission: ? Acute disease: ? Chronic disease: ? ```

Answer 33

``` Virus: CMV Incubation period: 10-21d Transmission: Close contact Acute disease: Rarely fulminant Chronic disease: Does not occur ```

Question 34

``` Virus: EBV Incubation period: ? Transmission: ? Acute disease: ? Chronic disease: ? ```

Answer 34

``` Virus: EBV Incubation period: 10-21d Transmission: close contact Acute disease: part of glandular fever syndrome Chronic disease: does not occur ```

Question 35

fulminant

Answer 35

severe and sudden in onset

Question 36

serology hep A

Answer 36

Antibody test for IgM and IgG

Question 37

serology hep B

Answer 37

antibody test for core antibody IgM, core antibody IgG, surface antibody e antibody Antigen: surface antibody e antigen

Question 38

serology hep C

Answer 38

antibody test: total (IgM/IgG) antibody | Nucleic acid test: hep C RNA (via PCR)

Question 39

serology Hep E

Answer 39

IgM | IgG