Childhood viral infections Flashcards Preview

Year 2 Clinical Pathology > Childhood viral infections > Flashcards

Flashcards in Childhood viral infections Deck (122)
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1
Q

Give 6 notifiable diseases which must be reported to public health England?

A

1) Acute meningitis
2) Acute poliomyelitis
3) Measles
4) Mumps
5) Rubella
6) Small pox

2
Q

What is the difference in productions of IgM and IgG in response to infection?

A

IgM is produced in acute infection - will rise in acute infection
IgG provides long term immunity - will be raised following infection and last for longer

3
Q

How can measurements of immunoglobulins be used in identifying infection?

A

Detection of IgM tells you the person currently has the infection
Detection of IgG tells you the person has had the infection in the past
NB. some early acute infections will have negative serology and pts may need to be tested a few days later to see if their is any rise if IgM

4
Q

Which kind of Ab is found in breast milk?

A

IgA

5
Q

Name 7 possible causes of a rash in a child?

A

1) Parovirus
2) Measles
3) Chickenpox
4) Rubella
5) Non-polio enterovirus infection
6) Epstein Barr Virus (with ampicillin)
7) Bacterial causes such as staphylococcus aureus, N. meningitidis

6
Q

When can Epstein Barr virus present with a rash?

A

When patients are given penicillin based Abx

Nb. if patients tell you they get a rash with penicillin it is important to note if that was because they had EBV

7
Q

Which virus causes measles and what kind is it?

A

Paramyxovirus

Enveloped single stranded RNA virus

8
Q

How is the measles virus spread?

A

Person to person, droplet spread

9
Q

When is a person with measles infectious?

A

From start of the first symptoms (4 days before rash to 4 days after disappearance of rash)

10
Q

What is meant by viral incubation?

A

The amount of time it takes for symptoms of a disease to appear after an individual is infected

11
Q

What is the incubation period of the measles virus?

A

7-18 days (average 10-12)

12
Q

Are humans the only natural host of the measles virus?

A

No

13
Q

What are the clinical features of measles?

A
Fever
Malaise
3C's: Conjunctivitis, cough and coryza
Rash
Koplik's spots 1-2 days before the rash
14
Q

Define coryza?

A

Catarrhal inflammation of the mucous membranes in the nose (runny nose)

15
Q

What are Koplik’s spots?

A

Small white spots seen on the tongue 1-2 days before a rash appears in a measles infection, only seen in measles

16
Q

What kind of rash is seen in measles?

A

Erythematous, maculopapular, head to trunk

17
Q

Define erythematous rash?

A

red rash

18
Q

Define maculopapular rash?

A

Type of rash characterised by a flat, red area on the skin that is covered in small confluent bumps

19
Q

What are the 4 less rare possible complications of measles?

A

1) Otitis media (inflammation of the middle ear)
2) Pneumonia (unlike bacterial pneumonia cant be cured by Abx)
3) Diarrhoea
4) Acute encephalitis - rare but fatal

20
Q

Name 1 very rare and fatal complication of measles?

A

Subacute sclerosing panencephalitis, 1/25000, occurs 7-30 years after measles

21
Q

What is the severity of measles infection in pregnancy?

A

Severe - up to 20% foetal losses

22
Q

In which groups is death from measles highest?

A
23
Q

What 4 factors can play a role in the diagnosis of measles?

A

1) Clinical
2) Leukopenia
3) Oral fluid sample
4) Serology

24
Q

What is the treatment for measles?

A

Supportive

Abx for superinfection

25
Q

What measures are put into place for prevention of measles?

A

MMR vaccine

Human normal immunoglobulin can be given to people who are immune compromised and at risk of infection

26
Q

What kind of vaccine is the MMR vaccine, when is it given?

A

Live vaccine

Given 1 year and a booster at pre school

27
Q

What virus causes chicken pox and what kind is it?

A

Varicella zoster virus

Herpes virus - DNA virus

28
Q

How is chicken pox virus transmitted?

A

Respiratory spread/ personal contact (face to face/ 15 mins)

29
Q

What is the incubation period of the chicken pox virus?

A

14-15 days

30
Q

What is the infectivity period of the chicken pox virus?

A

2 days before the onset of rash until after vesicles dry up

31
Q

Are humans the only host for the chicken pox virus?

A

Yes

32
Q

How can chicken pox lead to shingles?

A

Both caused by the varicella zoster virus
Chicken pox infection tends to occur in childhood, the virus remains dormant in the dorsal root ganglion
In some people the virus can re-present as shingles which is a rash confined to one dermatome, which is painful.

33
Q

What kind of rash occurs in Varicella zoster virus infection (chicken pox)?

A

Macular - popular - vesicular - pustular

34
Q

What is meant by a vesicular rash?

A

A rash featuring small blisters on the skin

35
Q

What are the 4 main clinical features of varicella zoster virus infection?

A

1) Fever
2) Malaise
3) Anorexia
4) Rash

36
Q

What are the 6 possible complications of varicella zoster virus infection?

A

1) Pneumonitis (risk increased for smokers)
2) Central nervous system involvement
3) Thrombocytopenic purpura (rare blood disorder, blood clots form in small vessels)
4) Foetal varicella syndrome (child born with cutaneous scars and limb defects etc. due to intrauterine infection)
5) Congenital varicella (child with abnormalities at birth due to pregnant mother infection)
6) Zoster (another name for shingles)
6) Zoster

37
Q

What 2 factors can play a role in diagnosis of varicella zoster virus?

A

1) Clinical diagnosis

2) PCR - vesicle fluid/CSF

38
Q

How are non-immune pregnant women protected against varicella zoster virus infection?

A

IgG given to pregnant women in contact with VZV and no history of chicken pox

39
Q

Which groups of people are given treatment for varicella zoster infection and what is that treatment?

A

Symptomatic adults and immunocompromised children given treatment:

1) Aciclovir oral, IV in severe disease or neonates
2) Chlorpheniramine can relieve itch (>1 year olds)

40
Q

Who is given a vaccine for varicella zoster virus and what kind is it?

A

Live vaccine, given in 2 doses
Given to everyone in US and Japan
In UK given to healthcare workers and susceptible contacts of immunocompromised patients

41
Q

For what 3 possible reasons could varicella zoster virus immunoglobulin be given, what should be noted about its use?

A

1) Significant exposure
2) A clinical condition that increases the risk of severe varicella eg. immunosuppressed patients, neonates and pregnant women
3) No Abs to varicella zoster virus
Ig does not prevent infection in all, reduces severity

42
Q

Which virus causes rubella and what kind is it?

A

Togavirus, an RNA virus

43
Q

How is rubella transmitted?

A

Droplet spread - air-bourne

Less contagious than VZV and measles

44
Q

What is the incubation period of rubella?

A

14-21 days

45
Q

What is the period of infectivity of rubella?

A

One week before rash to 4 days after

46
Q

Define prodrome?

A

An early symptom indicating the onset of illness

47
Q

What are the clinical features of rubella? 3

A

Prodrome - non specific
Lymphadenopathy - post-auricular, suboccipital
Rash

48
Q

What kind of rash occurs in rubella?

A

Very non specific, transient, erythematous, behind ears and face and neck

49
Q

What are the 3 possible complications in rubella?

A

1) Thrombocytopenia
2) Post infectious encephalitis
3) Arthritis

50
Q

What percentage of children with rubella are asymptomatic?

A

50%

51
Q

What are the 6 features of congenital rubella syndrome?

A

1) Cataracts and other eye defects
2) Deafness
3) Cardiac abnormalities
4) Microcephaly
5) Retardation of intra-uterine growth
6) Inflammatory lesions of the brain, liver, lungs and bone marrow

52
Q

When is congenital rubella syndrome more severe?

A

When infection is contracted earlier in pregnancy
Foetal damage is rare after 16/40, only deafness reported up to 20/40
Risk less than 11 weeks transmission: 90%
Risk 11-16 weeks transmission: 20%
Risk 16-20 weeks: minimal, deafness only
Risk >20 weeks transmission: no increased risk

53
Q

How is rubella diagnosed?

A

Oral fluid testing - IgM/G (PCR is within 7 days of rash)

54
Q

When are Ab detectable in rubella infection?

A

IgM and IgG detectable
Ab detectable from time of rash
IgM positive for 1-3 months - implications in pregnancy

55
Q

Is there any treatment for rubella?

A

No treatment available, immunoglobulin given to exposed pregnant women

56
Q

Is rubella vaccinated against?

A

Yes - MMR

initially this was only for 11-14 year olds, 2-3% of women of child bearing age remain susceptible

57
Q

What virus causes ‘slapped cheek’ or ‘fifth disease’ or parovirus B19, and what kind of virus is it?

A

B19 - a DNA virus

58
Q

How is B19 virus transmitted?

A

Transmitted by respiratory secretions or from mother to child

59
Q

What is the incubation period of parovirus B19?

A

4-14 days

60
Q

In what percentage of people is parovirus B19 asymptomatic?

A

20%

61
Q

What are the consequences of foetal parovirus B19? 2

A

Anaemia - can be treated with foetal transfusion

Hydrops (accumulation of fluid in 2 or more fetal compartments)

62
Q

What are the consequences of parovirus B19 infection in pregnancy?

A

Risk of miscarriage in early pregnancy but this is low

63
Q

What are the 5 clinical features of parovirus B19?

A
Minor respiratory illness
Rash illness (looks like slapped cheeks)
Arthralgia (joint pain)
Aplastic anaemia (deficiency of all types of blood cells)
Anaemia in the immunosuppressed - can be prolonged
64
Q

What 3 factors aid diagnosis of parovirus B19?

A

1) Serology IgM/IgG - 90% have IgM at time of rash
2) Amniotic fluid sampling
3) PCR in immunocompromised

65
Q

What is the treatment for Parovirus B19?

A

None if self limiting

Blood transfusion

66
Q

Is their a vaccine for parovirus B19?

A

no

67
Q

How can infections of Parovirus B19 be controlled?

A

Difficult as infectious prior to the arrival of the rash an significant number of cases are sub clinical
pregnant healthcare workers should avoid chronic cases

68
Q

What are enteroviruses?

A

Viruses so named because they reproduce initially in the GI tract after infections

69
Q

What 3 diseases can be caused by enteroviruses?

A

1) Hand, foot and mouth disease
2) Fever-rash syndromes
3) Meningitis - PCR of CSF to detect

70
Q

What percentage of enteroviral infections are asymptomatic?

A

90%

71
Q

How are enteroviral infections transmitted?

A

Faecal oral route and by skin contact

72
Q

How are enteroviral infections treated?

A

Supportive management and good hygiene to prevent transmission

73
Q

Give 6 viruses which commonly cause respiratory symptoms in children?

A

1) Respiratory syncytial virus
2) Parainfluenza
3) Influenza
4) Adenovirus
5) Metapneumovirus
6) Rhinovirus

74
Q

Respiratory syncytial virus is from what genus and causes what disease?

A

Its a pneumovirus

Can cause bronchiolitis in under 1 year old which can be life threatening, reinfections are common

75
Q

How is respiratory syncytial virus diagnosed?

A

PCR on secretions from nasopharyngeal aspirate

76
Q

What is the therapy of respiratory syncytial virus?

A

O2, manage fever and fluid intake
Previously used treatment such as bronchodilators/steroids are no longer recommended
Immunoglobulin and monoclonal Ab - palivizumab

77
Q

Metapneumovirus is from what genus and what sort of disease does it cause?

A

Paramyxovirus

Causes respiratory illness similar to RSV, ranges from mild upper respiratory tract infection to pneumonia

78
Q

How is metapneumovirus diagnosed?

A

PCR

79
Q

What is the therapy for metapneumovirus?

A

Supportive only

80
Q

What percentage of childhood respiratory infection does adenovirus account for?

A

10%

81
Q

What clinical features does adenovirus cause?

A

1) mild URTI - occasionally severe pneumonia
2) Conjunctivitis
3) Diarrhoea

82
Q

How is adenovirus diagnosed? 3

A

Respiratory panel PCR
Eye swab PCR
Serology possible

83
Q

What is the therapy for adenovirus infection?

A

None or cidofovir in immunocompromised

84
Q

What genus does parainfluenza virus belong to?

A

paramyxovirus

85
Q

How many types of parainfluenza virus are there?

A

4
1 in winter
3 in summer

86
Q

How is parainfluenza virus transmitted?

A

Person to person - inhalational

87
Q

What are the 3 clinical features of parainfluenza virus?

A

1) Croup
2) Bronchiolitis
3) URTI

88
Q

How is parainfluenza virus infection diagnosed?

A

Multiplexed PCR

89
Q

What is the therapy for parainfluenza virus?

A

There is no therapy

90
Q

Rhinovirus causes what?

A

Common cold

91
Q

Which 4 viruses cause similar clinical features to rhinovirus?

A

1) Coronavirus
2) Human bocavirus
3) Enterovirus
4) Adenovirus

92
Q

What genus does rhinovirus belong to?

A

Picornaviridae

93
Q

Rhinovirus is found in what percentage of children with mild upper respiratory tract symptoms?

A

70%

94
Q

What 2 viruses commonly cause diarrhoea in children?

A

Rotavirus

Norovirus

95
Q

What type of virus is rotavirus?

A

RNA virus

96
Q

How is rotavirus transmitted?

A

Faecal-oral route and occasionally respiratory - has a low infective dose

97
Q

What is the incubation period of rotavirus?

A

1-2 days

98
Q

What are the clinical features of rotavirus?

A

Diarrhoea and vomiting, shows seasonal variation, most common in 6/12-2years
Increased mortality in poorer countries

99
Q

How is rotavirus diagnosed?

A

PCR

100
Q

What is the treatment for rotavirus?

A

Rehydration

101
Q

How Is rotavirus prevented?

A

Oral live vaccine, Given at 2 and 3 months of age

102
Q

How is norovirus spread?

A

Food bourne virus - person to person spread

103
Q

What are the clinical features of norovirus?

A

High incidence of vomiting, short course - 12-60 hours

104
Q

How is norovirus diagnosed?

A

PCR

105
Q

How is norovirus treated?

A

Rehydration

106
Q

What family does the mumps virus belong to?

A

Paramyxoviridae family

107
Q

How is the mumps virus transmitted?

A

Direct contact, droplet spread, fomites (objects or materials that are likely to carry infection)

108
Q

What is the period of infectivity of the mumps virus?

A

Several days before parotid swelling to several days after

109
Q

What is the incubation period of the mumps virus?

A

2-4 weeks (mostly 16-18 days)

110
Q

What are the clinical manifestations of mumps?

A

Prodrome - non specific eg. low grade fever, anorexia, malaise and headache
Next 24 hours - earache, tenderness over ipsilateral parotid
Next 2-3 days - gradually enlarging parotid with severe pain (normally bilateral but can be unilateral in 25%)
Pyrexia up to 40 degrees
After peak swelling, pain, fever and tenderness rapidly resolve and the parotid gland returns to normal size within one week

111
Q

What are the 7 rare manifestations of the mumps virus?

A

1) Submandibular and/or sublingual sialadenitis (inflammation of a salivary gland)
2) Epididymo-orchitis (inflammation or epididymis and/or testis)
3) Oophoritis (inflammation of an ovary)
4) Meningitis
5) Encephalitis
6) Renal function abnormalities (mild)
7) Pancreatitis

112
Q

What is the most common extrasalivary gland manifestation of mumps?

A

CNS involvement

113
Q

What is the most common extrasalivary manifestation of mumps in adults?

A

Epididymo-orchitis

114
Q

What are the consequences of mumps infection in pregnancy?

A

Infection in first trimester - increased foetal death

115
Q

What investigations aid diagnosis of mumps?

A
Have a normal white cell count
Raised serum amylase - salivary or pancreatic
Normally clinically diagnosed
Serology IgM - blood and saliva
PCR
116
Q

What is the treatment for mumps?

A

Symptomatic treatment

117
Q

Is there a vaccine for mumps?

A

Yes, MMR

118
Q

Which 7 viruses can cause neonatal/congenital infection?

A

1) Varicella zoster virus
2) Rubella
3) Cytomegalovirus
4) Toxoplasma
5) Herpes simplex virus
6) Hepatitis B virus
7) HIV

119
Q

What are the symptoms of congenital cytomegalovirus infection? 3

A

Growth retardation, deafness, blindness

120
Q

What are the clinical features of toxoplasma congenital disease? 2

A

Chorioretinitis (inflammation of the choroid and retina of the eye)
Hydrocephaly

121
Q

What is given to neonates born to mothers with hepatitis B infection?.

A

Hep B immunoglobulins/vaccine for neonate

122
Q

What 3 parts of the history from parents are very important when a child presents with a possible viral infection?

A

1) Vaccination history
2) Travel history
3) Contact history

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