Viral infections in childhood

Question 1

Describe the generic structure of a virus

Answer 1

• Nucleic acid

- Protein coat with or without envelope

Question 2

Is DNA double or single stranded in viruses

Answer 2

Double (single in parovirus)

Question 3

Is RNA double or single stranded

Answer 3

Single (double stranded RNA in reoviruses)

Question 4

Are viruses intra or extracellular

Answer 4

Intracellular

Question 5

Name the 5 steps in the viral life cycle

Answer 5

• Attachment
• Entry
• Uncoating
• Synthesis of viral components
• Assembly and release

Question 6

Where are the receptors that viruses attach to

Answer 6

On the plasma membrane

Question 7

3 places that uncoating can take

Answer 7

• Endosome (receptor mediated endocytosis)
• Cytosol
• Nuclear membrane

Question 8

What enzymes can DNA viruses use

Answer 8

Cellular viruses

Question 9

Why must viruses carry their own enzymes

Answer 9

All viruses apart from DNA viruses need to make their own cellular components

Question 10

What releases the newly produced virions

Answer 10

Cell lysis

Budding

Question 11

Name 3 enveloped DNA viruses

Answer 11

Herpes viruses
Hep B
Pox virus

Question 12

Give 5 examples of Herpes viruses

Answer 12

Herpes simplex
Varicella zoster
CMV
Epstein- Barr
HHV

Question 13

Give 3 examples of non-enveloped DNA viruses

Answer 13

Papillomarvirus
Adenovirus
Parovirus

Question 14

Give 2 clinical manifestation of herpes simplex in older children and adults

Answer 14

• Herpes labilalis= cold sore

- Herpetic whitlow- sore on fingers

Question 15

State 2 clinical manifestations of herpes simplex in neonates

Answer 15

Disseminated HSV

HSV encephalitis

Question 16

What is disseminated HSV

Answer 16

Sepsis-like syndrome which can lead to hepatitis and coagulopathy

Question 17

How is disseminated HSV treated

Answer 17

IV aciclovir

Question 18

What is HSV encephalitis

Answer 18

Fevers, seizures

Haemorrhagic infarction of white matter and cortex

Question 19

In what kind of people is cytomegalovirus severe

Answer 19

Immunosuppressed

Question 20

What is the commonest congenital infection in the developed world

Answer 20

CMV

Question 21

Long term effect of CMV

Answer 21

Long term sensorineural hearing loss

Question 22

How do you treat congenital CMV

Answer 22

IV ganciclovir or oral valganciclovir which is the pro-drug

Inhibits DNA synthesis

Question 23

Problems when treating CMV

Answer 23

Neutropenia
Thrombocytopenia
IV access?

Question 24

What virus causes chicken pox

Answer 24

varicella zoster virus

Question 25

What does Epstein- Barr virus lead to

Answer 25

Infective mononucleosis (glandular fever)

Question 26

How is EPV spreadd

Answer 26

saliva

Question 27

What can EBV lead to in Africa

Answer 27

Burkitt's lymphoma

Question 28

What do HHV-6 and 7 lead to

Answer 28

Soseola infantum

Question 29

What ages are HHV-6 and 7 in

Answer 29

6 months- 2 years

Question 30

Symptoms of roseola infantum

Answer 30

Sudden onset of high fever, lasts a few days and then suddenly stops, rash appears

Question 31

What determines chronicity of Hep B

Answer 31

age at infection

Question 32

Stages of Hep B

Answer 32

Tolerance Clearance Latency Reactivation

Question 33

Name 2 consequences of hep B

Answer 33

Cirrhosis | Hepatocellular carcinoma

Question 34

What does poxvirus lead to

Answer 34

Smallpox

Question 35

How was smallpox eradicated

Answer 35

Combo of routine vaccination, isolation of cases/ outbreak control

Question 36

Where are poxes found in normal people

Answer 36

Moist areas such as groin, axilla

Question 37

Which virus is a cause of cervical cancer

Answer 37

Papillomarvirus

Question 38

What serotypes of papillomavirus are carcinogenic

Answer 38

16 and 18

Question 39

What serotypes of papillomavirus lead to genital warts

Answer 39

6, 11

Question 40

Symptoms of adenovirus infection

Answer 40

URTI/ pneumonia Conjuctivitis Diarrhoea

Question 41

How does parovirus B19 act in not susceptible hosts

Answer 41

It attaches to group P antigens so people lacking P antigen not susceptible

Question 42

What happens if a highly susceptible person is infected with parovirus B19

Answer 42

Replicates in rapidly dividing cells in people with haematological problems leads to aplastic crisis

Question 43

What facial feature is specific to parovirus B19

Answer 43

Slapped cheek

Question 44

Name 4 enveloped RNA viruses

Answer 44

- MMR - RVS - Hep C - HIV

Question 45

Name 3 unenveloped RNA viruses

Answer 45

- Rotavirus - Enteroviruses - Hep A

Question 46

Incubation period of measles?

Answer 46

7-14 days

Question 47

What are the symptoms of measles in order of appearance

Answer 47

first- fever, cough, conjunctivities second- Koplik spokts third- rash

Question 48

Colloquial name for rubella

Answer 48

German measles

Question 49

Triad seen in congenital rubella

Answer 49

Eyes- cataracts, micro-opthalmia, glaucoma Ears- sensorineural deafness Heart- VSD, pulmonary artery stenosis

Question 50

What is broncholitis

Answer 50

Viral infection of infants causing an inflammation of bronchioles Symptoms= cough, resp distress, wheeze

Question 51

What drug is used to prevent bronchiolitis

Answer 51

Palivizumab

Question 52

What is the risk of mother to child transmission in Hep C

Answer 52

approx 5%

Question 53

Is HIV infection more severe in infants or adults

Answer 53

Infants

Question 54

Why is HIV infection more severe in infants

Answer 54

``` High viral loads Rapid progression No reliable markers Fewer drug options Challenging adherence ```

Question 55

What is the most common cause of hospital admission for diarhhoea

Answer 55

Rotavirus

Question 56

Features of rotavirus diarrhoea

Answer 56

Fever, vomiting, watery diarrhoea

Question 57

What 2 oral vaccines are available for rotavirus

Answer 57

RotaTeq | RotaRix