Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

X Infectious Diseases > MMR > Flashcards

MMR Flashcards

1
Q

what is the organism that causes measles?

A

Morbillivirus genus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the genome of measles?

A

Single stranded
non-segmented
RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the features of measles?

A 
Cell membrane derived envelope
 Replicates in cytoplasm
 Major killer in developing world  (1 million children / year )
 Transmission by aerosol droplets
 Very contagious
 No therapy - supportive care only
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the structure of the measles virus?

A

Haemagglutinin-neurominidase (like flu)

genome in 1 big long strand

fusion protein in the lipid bilayer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how is measles transmitted?

A

All discharges carry virus
Contact with infected person
Viral particles remain infectious for several hours
Aerosol transmission ONLY over short distances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the pathogenesis of measles?

A

Damage due to viral invasion, cytopathic changes and host response

Virus replicates in respiratory tract and mucosae

Infects lymphoid tissue and bone marrow

Infects epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the symptoms of measles?

A

9-11 days after exposure to virus - fever of 38.3°C

Coryza (runny nose) and cough (virus attacks respiratory tract)

Conjunctivitis (sore eyes)

Koplik’s spots (virus attacks mucosa) 1-3 days after respiratory symptoms

Maculopapular rash (virus attacks epithelial cells) develops a day after Koplik’s spots

Lymphadenopathy – immune suppression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the characteristics of a measles rash?

A

Virus antigens and particles in the tissues

Develops over 2-3 days and then fades

T-cells targeting infected endothelial cells in the small blood vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how are Koplik’s spots described?

A

“grains of salt surrounded by red halo”

salt crystals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the sequence of antibodies produced against measles?

A

IgM - first antibodies

IgG - specific - produced later

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Typical case study:

Developed rash in last 24 hours

Unwell for 3 days, fever, runny nose and unproductive cough

On examination as well as a rash, patient miserable and febrile, no evidence of lower respiratory tract disease

What is it?

A

Measles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how can you diagnose measles?

A

Koplik’s spots - small greyish white lesions in mouth that fade once rash appears

Virus isolation (from onset of symptoms - day 2-3 of rash) expensive & slow technique

Serodiagnosis: haemagglutination inhibition or ELISA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

typical case study COMPLICATIONS:

Rash spreads to trunk and limbs and begins to fade, leaving a brownish discolouration.

Respiratory symptoms improve and fever subsides.

Day 6 after onset of rash, patient complains of headache, becomes increasingly irritable and fever returns.

what is it?

A

measles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the complications of measles?

A

Superinfection of middle ear or lung - viral or bacterial pneumonia

Secondary infection with varicella-zoster virus & influenza virus

Neurological complication - Meningoencephalitis (1/1000 cases) deafness, mental retardation, seizures

Neurological complication - Subacute sclerosing pan encephalitis (SSPE). Develops 1- 10 years after disease, progressive resulting in coma and death. Incidence decreased since vaccination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the characteristics of measles in developing countries?

A

Immunosuppressive effects linked to malnutrition

Infection complicated by bacterial pneumonia & diarrhoea

Major cause of death (5 -15% mortality)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how has the number of measles cases dropped due to vaccinations?

A

In 2015, there were 134 200 measles deaths globally – about 367 deaths every day or 15 deaths every hour.

Measles vaccination resulted in a 79% drop in measles deaths between 2000 and 2015 worldwide.

In 2015, about 85% of the world’s children received one dose of measles vaccine by their first birthday through routine health services – up from 73% in 2000.

During 2000-2015, measles vaccination prevented an estimated 20.3 million deaths making measles vaccine one of the best buys in public health

17
Q

what are the characteristics of MMR vaccination?

A

Live attenuated vaccine - stable under refrigeration
Inexpensive
Administered as MMR - with mumps and rubella vaccines
Gives long term immunity
Does not spread from vaccinated person

18
Q

what organism causes mumps?

A

Rubulavirus Genus

19
Q

what virus is mumps similar to?

A

Paramyxovirus

20
Q

how many serotypes of mumps are there?

A

1

21
Q

what is the reservoir of mumps

A

humans ONLY

22
Q

what is the pathogenesis of mumps?

A

Respiratory infection - virus replicates in nasopharynx
Spreads to regional lymph nodes
Viremia (virus in blood) - spread to multiple tissues causing inflammation
Salivary glands to cause inflammation (parotitis)
Meninges (lining of brain) to cause aseptic meningitis
Testes to cause inflammation (orchitis)

23
Q

what are the symptoms of mumps?

A

Fever and headache
Muscle aches
Tiredness and loss of appetite

Parotitis (inflammation of salivary glands)
observed in around 40% patients
persists 7-10 days

Meningitis occurs - usually mild
50% patients asymptomatic
but more severe in adults

24
Q

typical case study:

Developed pain tenderness and difficulty swallowing in last 24-48 hours

Unwell for 3 days, fever, sickness and headache

On examination patient is miserable and febrile with swelling of one or more parotid glands

what is it?

A

mumps

25
Q

what are the complications of mumps?

A

More severe in adults
Deafness
Orchitis (testicular inflammation)
Pancreatitis, myocarditis,
Inflammation of ovaries (oophoritis) and breasts (mastitis) in females who have reached puberty
Encephalitis (Inflammation of the brain) and meningitis (inflammation of lining of brain and spinal cord)

26
Q

what are the characteristics of rubella?

A

Means “little red” in Latin (German measles)
Single stranded positive sense non segmented RNA virus
Cell membrane derived envelope
Replicates in cytoplasm
Similar transmission of virus
No therapy - supportive care only
Vaccine – MMR (one serotype of virus)

27
Q

what is the viral structure of rubella?

A

glycoproteins on the surface for attachment

icosahedral capsid

RNA single-stranded positive-sense

28
Q

how is rubella transmitted/spread between people and in the body?

A

Transmitted via direct or droplet contact with respiratory secretions

Virus replicates in respiratory mucosa

Infects lymphatic system

Viraemia (virus in blood) results in systemic infection of other organs

29
Q

what are the symptoms of rubella?

A 
Appearance of red pink rash on face which spreads to trunk and limbs 
 Rash usually fades after three days
 Low grade fever
 Swollen parotid glands 
 Headache 
 Conjunctivitis

Complications very rare

30
Q

what are the characteristics of a rubella rash?

A

A red-pink rash

Number of small spots, which may be slightly itchy

Rash usually starts behind the ears and spreads to head and neck

May then spread to chest, stomach, legs and arms

31
Q

Typical case study:

Developed red rash on the face which spreads to rest of body

Fever, tiredness, loss of appetite and headache

On examination patient is febrile with swelling of lymph glands, joint pain and cold like symptoms (runny nose, watery eyes, sore throat and cough)

what is it?

A

rubella

32
Q

what is congenital rubella syndrome?

A

Infection of the foetus in utero

Mother acquires Rubella during first trimester

33
Q

what are the symptoms of congenital rubella syndrome?

A

20% children suffer severe congenital abnormalities with 10-20% death rate

- Deafness 
   	- Blindness
   	- Congenital heart disease
   	- Mental retardation
   	- Growth retardation
   	- Hepatosplenomegaly
34
Q

what are rare complications of rubella?

A

Rare complication:
thrombocytopenic (lack of platelets) purpura (red rash)

Rare complication – post infectious encephalopathy (brain infection)

35
Q

what kind of genome is measles?

A

negative sense

36
Q

wha does positive sense genome mean?

A

ready to be made to code for protein

37
Q

what is key about the genome of rubella?

A

doesn’t have a DNA genome

X Infectious Diseases (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions