(6) Childhood Viral Infections Flashcards
(179 cards)
1
Q
What are the classifications of viral illness in childhood?
A
- asymptomatic/subclinical infection
- fever and a rash
- respiratory tract infections
- gastro-intestinal infections
- others (eg. mumps, meningitis etc)
2
Q
What is a notifiable disease?
A
Any disease that is required by law to be reported to government authorities
Report to Public Health England
3
Q
Give some examples of notifiable disease
A
- acute meningitis
- acute poliomyelitis
- measles
- mumps
- rubella
- smallpox
4
Q
Which antibody is produced in acute infection (first antibody to appear in response to initial exposure to an antigen)?
A
IgM
5
Q
Which antibody is involved in long term immunity ?
A
IgG
6
Q
Which is the maternal antibody?
A
IgG
7
Q
Which antibody is in breast milk?
A
IgA
8
Q
Levels of which antibody increase significantly after 2nd exposure to an antigen?
A
IgG
involved in long term immunity
9
Q
Give some viral causes of rash in children
A
- parvovirus
- measles
- chickenpox
- rubella
- non-polio enterovirus infection
- EBV (with ampicillin)
(bacterial causes = staph. aureus, n. meningitidis)
10
Q
What is the measles virus?
A
Paramyxovirus
11
Q
What type of virus is paramyxovirus (the measles virus)?
A
Enveloped single stranded RNA virus
12
Q
How is measles transmitted?
A
Person to person
Droplet spread
13
Q
What is the infectivity of measles?
A
From the start of first symptoms (4 days before rash)
To 4 days after disappearance of rash
14
Q
What is an incubation period?
A
The time between exposure to a pathogenic organism and when symptoms and signs are first apparent
Signifies the period taken by the multiplying organism to reach a threshold necessary to produce symptoms in the host
15
Q
How long is the incubation period for measles?
A
7-18 days (average 10-12 days)
16
Q
What is the natural host for measles?
A
Humans are the only natural host
no animals have measles - so there is potential for eradication
17
Q
What is the distribution of measles?
A
Worldwide
18
Q
How long can paramyxovirus last in airspace?
A
2 hours
15 minutes contact time is considered highly significant
19
Q
How many cases of measles were there in England in 2014?
A
Just over 100
all unvaccinated, most children/young adults
about half occur on return from abroad
20
Q
What is a prodrome?
A
An early symptom (or set of symptoms) that might indicate the start of a disease before specific symptoms occur
21
Q
What is the prodrome for measles?
A
- fever
- malaise
- conjunctivitis
- coryza
- cough
(3 Cs)
22
Q
What is coryza?
A
Rhinitis or coryza is irritation and inflammation of the mucous membrane inside the nose. Common symptoms are a stuffy nose, runny nose, sneezing, and post-nasal drip
23
Q
Describe the rash you get in measles
A
- erythematous
- maculopapular
- head-trunk
24
Q
What is a maculopapular rash?
A
A type of rash characterised by a flat, red area on the skin that is covered with small confluent bumps
25
What feature in the mouth is a prodromic sign of measles, 1-3 days before the appearance of rash?
Koplik's spots
26
What are Koplik's spots?
Early sign of measles, 1-3 days before rash
Clustered, white lesions on the buccal mucosa
Ulcerated mucosal lesions marked by necrosis, neutrophilic exudate, and neovascularization
27
As well as the prodrome, rash and Koplik's spots, what are the other clinical features of clinical features of measles?
- fever
| - infection in the immunocompromised
28
Give the main clinical features of measles
Rash + fever + cough/coryza/conjunctivitis
29
What are the common potential complications of measles?
- otitis media (7-9%)
- pneumonia (1-6%)
- diarrhoea (8%)
30
What is otitis media?
Otitis media is a group of inflammatory diseases of the middle ear
31
Which potential complication of measles is rare but fatal?
- acute encephalitis (1 in 2000)
| - subacute sclerosing panencephalitis (SSPE) (1 in 25000)
32
How long after measles does SSPE occur?
7-30 years after measles
33
What is subacute sclerosing pan encephalitis (SSPE)?
A rare and chronic form of progressive brain inflammation caused by a persistent infection with measles virus
34
How serious is measles infection in pregnancy?
Severe
Up to 20% foetal loss
35
Most complications occur in measles in patients of what age?
Less than 5 years old or over 20 years old
36
Hearing loss can occur in patients with measles following what?
Measles related otitis media
37
Measles causes death in children following which complication?
Pneumonia
38
How is measles diagnosed?
- clinical
- leukopenia
- oral fluid sample
- serology
39
What is leukopenia?
A reduction in the number of white cells in the blood, typical of various diseases
40
What does treatment for measles involve?
- supportive
| - antibiotics for superinfection
41
How is measles prevented?
- vaccine (live MMR) - 1 year, pre-school
| - human normal immunoglobin
42
When was the measles vaccine introduced?
1968
43
Coverage of measles vaccination rose >90% following introduction of what?
MMR vaccine in 1988
44
What is the national MMR catch up programme?
Aims to vaccinate 10-16 year olds from 2013 onwards
45
How many cases of measles were there prior to 1968 when the first vaccine was introduced?
Up to 800,000 cases a year
46
Which virus causes chicken pox?
Varicella Zoster Virus
Herpes virus - DNA virus
47
How is chicken pox (varicella zoster virus) transmitted?
Respiratory spread/personal contact (face to face/15 mins)
48
What is the incubation period of chicken pox/varicella zoster virus)?
14-15 days
49
What is the infectivity of chicken pox?
2 days before onset of rash until after vesicles dry up
50
What is the host of chicken pox/varicella zoster virus?
Humans are the only host
51
What are the main clinical features of chicken pox?
- fever
- malaise
- anorexia
- rash
52
Describe the rash in chicken pox
Centripetal
macular - papular - vesicular - pustular
53
What are the potential complications in chicken pox/vzv?
- pneumonitis (increased risk for smokers)
- CNS involvement
- thrombocytopenic purpura
- foetal varicella syndrome
- congenital varicella
- zoster
54
What is thrombocytopenic purpura?
A disorder that can lead to easy or excessive bruising and bleeding - results from unusually low levels of platelets
55
What is congenital varicella syndrome?
Rare disorder in which affected infants have distinctive abnormalities at birth due to the mother's infection with chickenpox early during pregnancy
- low birth weight
- characteristic abnormalities of the skin; the arms, legs, hands, and/or feet; the brain; the eyes
56
What is zoster commonly known as?
Shingles
57
What makes chicken pox patients at higher risk of severe disease/complication?
Smokers or those taking steroids
58
How is chicken pox/vzv diagnosed?
- clinical
| - PCR - vesicle fluid/CSF
59
When is chicken pox serology used?
In pregnant women who have come into contact with chicken pox and don't think they have had it before - serious
60
What is used to test whether a pregnant woman already has immunity to chicken pox?
Serology
Test IgG
positive = good, have immunity
61
Why is chicken pox so serious in pregnant woman?
Likely the mother will get it very badly and can also affect the baby - limb abnormalities and scarring
62
Who is treatment for chicken pox used in?
Symptomatic adults and immunocompromised children
63
What is used as treatment for chicken pox?
Aciclovir (oral, IV in severe disease or neonates)
Chlorpheniramine can relive itch (>1 year olds)
64
Is chicken pox a notifiable disease?
Not in England but is in Scotland/NI
65
Why is treatment for chicken pox not recommended for healthy children? (is recommend in over 14 year olds)
Studies did not show a reduction in complications (though aciclovir did reduce the number of skin lesions and duration of fever)
66
Describe the chicken pox vaccine
- live
- 2 doses
(USA/Japan)
67
Who receives the chicken pox vaccine?
- health care workers
| - susceptible contacts of immunocompromised patients
68
When is VZ immunoglobin (VZIG) given?
- a significant exposure
- a clinical condition that increases the risk of severe varicella e.g. immunocompromised, neonates, pregnant woman
- no antibodies to VZ virus
Ig does not prevent infection in all, but it reduces severity
69
Which virus causes rubella?
Togavirus, RNA virus
70
How is rubella/togavirus transmitted?
Droplet spread - airborne
Less contagious
71
How long is the incubation period for rubella?
14-21 days
72
When is the infectivity of rubella?
1 week before rash to 4 days after
73
Is there a rubella problem in the UK?
Only reported cases in the UK last year were imported
74
What are the general clinical features of rubella?
- non-specific prodrome
- lymphadenopathy
- rash
75
Lymphadenopathy is a clinical feature of rubella. Which lymph nodes does it affect?
- post-auricular
| - suboccipital
76
Describe the rash in rubella
Very non-specific
Transient, erythematous, behind ears and face and neck
Starts on face and spread to rest of body
77
Which symptom of rubella is particularly seen in young female patients?
Aching joints
78
Give some complications of rubella
- thrombocytopenia
- post infectious encephalitis
- arthritis
79
How many children with rubella are asymptomatic?
50%
80
Is rubella a severe disease?
It is a mild and usually self-limiting infection but can be devastating in pregnant women
81
Is rubella risky in the immune-compromised?
Not particularly risky
82
What is congenital rubella syndrome (CRS)?
Can occur in a developing foetus of a pregnant woman who has contracted rubella
83
What are the symptoms of CRS?
- cataracts and other eye defects
- deafness
- cardiac abnormalities
- microcephaly
- retardation of intra-uterine growth
- inflammatory lesions of brain, liver, lungs and bone marrow
84
When is CRS more severe?
When the rubella infection is contracted earlier in pregnancy
85
What is the risk of intra-uterine transmission of rubella, less than 11 weeks of pregnancy?
90%
86
What is the risk of intra-uterine transmission of rubella, 11-16 weeks into pregnancy?
20%
87
What is the risk of intra-uterine transmission of rubella, 16-20 weeks into pregnancy?
Minimal risk, deafness only
88
What is the risk of intra-uterine transmission of rubella, >20 weeks into pregnancy?
No increased risk
89
How is rubella diagnosed?
- oral fluid testing - IgM/G - PCR if within 7 days of rash
| - serology - IgM and IgG - antibodies detectable from time of rash
90
What is the treatment for rubella?
There is no treatment available
Immunoglobin given to exposed pregnant women
91
Is there evidence that human normal immunoglobin is effective?
No, but may be given in confirmed rubella cases where termination of pregnancy is unacceptable
92
How many women of child bearing age remain susceptible to rubella?
2-3%
93
When was the rubella vaccine introduced?
1970
94
When was the MMR vaccine introduced?
1988
95
When was the catch up MR vaccine introduced?
1994
96
Which virus causes 'slapped cheek' or 'fifth disease'?
Parvovirus B19 - DNA virus
97
How is parvovirus B19 transmitted?
By respiratory secretions or from mother to child
98
What is the incubation period for parvovirus B19?
4 to 14 days
99
What problem concerning pregnancy does parvovirus B19 cause?
Risk of miscarriage in early pregnancy, but the risk is low
Can cause foetal disease - foetal anaemia and foetal hydrops
100
How many of those infected with parvovirus B19 are asymptomatic?
20%
101
When are children with slapped cheek infective?
Before rash appears
No longer infective when they have the rash
102
What are the clinical features of parvovirus B19?
- minor respiratory illness
- rash illness "slapped cheek" (can also get secondary itchy rash over body)
- arthralgia
- aplastic anaemia
- anaemia in the immunosuppressed (this may be prolonged)
103
What is arthralgia (a symptom of parvovirus B19)?
Pain in the joints
104
Whats is aplastic anaemia?
Deficiency of all types of blood cell caused by failure of bone marrow development
105
How is parvovirus B19 diagnosed?
- serology IgM/IgG - 90% have IgM at time of rash
- amniotic fluid sampling
- PCR in immunocompromised
106
What is the treatment for parvovirus B19?
- none if self limiting illness
- blood transfusion
- no vaccine available
107
Why is infection control for parvovirus B19 difficult?
It is infectious prior to the arrival of the rash and significant number of cases are subclinical
108
Is parvovirus B19 a notifiable disease?
No
109
Give some examples of enteroviral infections
- coxsackie
- entero
- echviral infections
110
How many cases of enteroviral infections are asymptomatic?
90%
111
In what age group are enteroviral infections prevalent?
Under 5 year olds
112
How are enter viral infections transmitted?
Faecal-oral
Skin contact
113
Hand, foot and mouth disease is a type of what?
Enteroviral infection
114
What type of syndrome do enteroviral infections cause?
Fever-rash syndromes
115
What more serious condition can enteroviral infections cause?
Meningitis - diagnosed by PCR of CSF
116
What treatment is given for enteroviral infections?
None
Supportive management and good hygiene to prevent transmission
117
Which viruses may be the cause of respiratory symptoms in a child?
- respiratory syncytial virus
- parainfluenza
- influenza
- adenovirus
- metapneumovirus
- rhinovirus
118
Bronchiolitis is caused by which virus?
Respiratory syncytial virus (RSV)
119
What are the features of bronchiolitis?
- under 1 year olds
- annual winter epidemic
- incubation = 4-6 days
- can be life threatening
- reinfections common
120
How is RSV diagnosed?
PCR on secretions from nasopharyngeal aspirate
121
How is RSV managed?
- O2, manage fever and fluid intake
- previous treatment eg. bronchodilators/steroids no longer recommended
- vulnerable cases eg. neonates, palivizumab is given (immunoglobin and monoclonal antibodies - very expensive)
122
What is metapneumovirus?
- recently discovered virus
- paramyxovirus
- nearly universal by aged 5
123
What symptoms does metapenumovirus cause?
Respiratory illness similar to RSV - ranges from respiratory tract infection to pneumonia
124
How is metapneumovirus diagnosed?
PCR
125
How is metapneumovirus managed?
Supportive only
126
Adenovirus accounts for how many childhood respiratory infections?
10%
127
What are the clinical features of adenovirus?
- mild URTI (occ. severe penumonia)
- conjunctivitis
- diarrhoea (serotypes 40/41)
128
How is adenovirus diagnosed?
- respiratory panel PCR
- eye swab OCR
- serology if possible
129
How is adenovirus treated/managed?
No treatment
But cidofovir in immunocompromised
130
What is parainfluenza?
- paramyxovirus
| - 4 types (1 in winter, 3 in summer)
131
How is parainfluenza transmitted?
Person to person
Inhalation
132
What are the clinical features of parainfluenza?
- croup
- bronchiolitis
- URTI
133
How is parainfluenza diagnosed?
Multiplexed PCR
134
What is the treatment for parainfluenza?
None
135
Rhinovirus is a member of which family?
Picornaviridae
136
Which virus causes the common cold?
Rhinovirus
137
Which virus is found in approximately 70% of children with mild upper respiratory tract symptoms?
Rhinovirus
138
Rhinovirus causes similar clinical features to which other viruses?
- coronavirus
- human bocavirus
- enterovirus
- adenovirus
139
Which viruses may be responsible for a child with diarrhoea?
- rotavirus
| - norovirus
140
What type of virus is rotavirus?
Reovirus (RNA virus)
141
How is rotavirus transmitted?
Faecal-oral and occasionally respiratory
Low infectious dose!
142
What is the incubation period for rotavirus?
1-2 days
143
What is the epidemiology of rotavirus?
- seasonal in UK (winter/spring)
- worldwide
- 440,000 deaths per year
144
What are the clinic features of rotavirus?
- diarrhoea
- vomiting
Seasonal variation
Increased mortality in poorer countries
145
How is rotavirus diagnosed?
PCR
146
How is rotavirus treated?
Rehydration
147
How is rotavirus infection prevented?
Oral live vaccine - UK introduction in 2013 - given at 2 and 3 months of age
148
What is norovirus known as?
"winter vomiting bug"
High incidence of vomiting (>50%)
149
Where are norovirus outbreaks seen?
- nurseries
- hospitals
- cruise ships
150
How is norovirus spread?
Person to person
Foodborne disease
151
Does norovirus have a long or short course?
Short course - 12-60 hours
152
How is norovirus diagnosed?
PCR
153
How is norovirus treated?
Rehydration
154
Which family does the mumps virus belong to?
Paramyxoviridae family
155
How is mumps transmitted?
Direct contact
Droplet spread
Fomites
156
Describe the infectivity of mumps?
Several days before parotid swelling to several days after
157
What is the incubation period for mumps?
2-4 weeks (mostly 16-18 days)
158
When was the MMR vaccine introduced?
1988
Catch up in 1994
159
How has the epidemiology of mumps changed?
In the pre-vaccine era..
- 90% of infections in 85% of adults immune because of previous childhood infection
In 2001...
- 49% of infections were in >15s
- no natural immunity
160
How common is mumps?
More common in the UK than measles or rubella (2013) - cases occurred in young adults of 17-28 years of age
161
More than half of cases of mumps have had one dose of MMR. Why is this?
Waning immunity
162
What is the mumps prodrome?
Non-sepcific
eg. low-grade fever, anorexia, malaise, and headache
163
What happens in the next 24 hours after mumps prodrome?
Earache, tenderness over ipsilateral parotid
164
What happens in the next 2-3 days after initial symptoms of mumps?
Gradually enlarging parotid with severe pain
165
Is mumps unilateral or bilateral?
Normally bilateral but can be unilateral in at least 25%
166
Give another symptom of mumps other than fever, earache and parotid swelling and pain
Pyrexia up to 40c
167
What happens 1 week after initial mumps symptoms?
After peak swelling, pain, fever and tenderness rapidly resolve, and the parotid gland returns to normal size within 1 week
168
What are some rare manifestations of mumps?
- submandibular and/or sublingual sialadenitis
- epididymo-orchitis
- oophoritis
- meningitis
- encephalitis
- renal function abnormalities (mild)
- pancreatitis
169
What is sialadentitis?
Inflammation of a salivary gland
170
What is epididymo-orchitis?
Inflammation of the epididymis and/or testis
171
What is oophoritis?
Inflammation of an ovary
172
What is the most common extra salivary gland manifestation of mumps?
CNS involvement
173
What is the most common extra salivary gland manifestation of mumps in the adult?
Epididymo-orchitis
174
What happens if mumps infection occurs in the first trimester?
Increased foetal death
175
What investigations would be carried out in mumps?
- normal WCC
| - raised serum amylase (salivary or pancreatic)
176
How is mumps diagnosed?
Normally clinical diagnosis
Serology (IgM)
- blood
- saliva
(PCR)
177
What is the treatment for mumps?
Symptomatic only
178
Is mumps vaccine preventable?
Yes, live attenuated vaccine
179
Which viruses can cause a problem in neonates/congenital infection?
- VZV
- rubella
- CMV - growth retardation, deafness, blindness
- toxoplasma - chorioretinits, hydrocephaly
- HSV - severe neonatal disease
- HBV - HBIG/vaccine for neonate
- HIV - see BHIVA guidelines etc
