Childhood Virues

Question 1

True or False:

Most Childhood Viral dieses are exclusively human and induce life long immunity.

Answer 1

True

Question 2

True or False:

Measles (rubeola) and Mumps belong to the paramyxoviruses family.

Answer 2

True

Question 3

What is a Paramyxovirus?

Answer 3

Enveloped (Class V) ss(-) RNA

Question 4

True or False:

Rubeola (Measles) is a newer discovered virus hard to transfer but transmitted by hugs.

Answer 4

False:

Known since Antiquity, Very contagious transmitted by contact with respiratory secretions

Question 5

What appears as a sure sign of Rubeola infection?

Answer 5

Koplik’s spots (Rash in the mucosa)

Question 6

How long does a Rubeola infection usually last?

Answer 6

7 to 10 days

Question 7

True or False:

Rubeola usually only effects the upper trunk and head of the infection individual. Complications are rare, but include giant cell pneumonia.

Answer 7

True

Question 8

Detection serology involves which anti measles Ig?

Answer 8

IgM

Question 9

True or False:

Measles infection is widespread and common.

Answer 9

False

Vaccines have made measles a rare infection in the world today.

Question 10

Mumps infections are __% subclinical. Very contagious __ days before the infection becomes clinically apparent until about __ days afterwards

Answer 10

30, 7, 9

Question 11

How many known serotypes are there for the Mumps virus and what other species is it found in?

Answer 11

Only 1 serotype and humanity is the only known host

Question 12

Mumps has the ability to infect the lymph nodes from the reparatory system due to what?

Answer 12

Viremia

Question 13

How long is the incubation period of Mumps?

Answer 13

18 days

Question 14

What kind of vaccine is MMR (measles mumps rubeola) and is it effective??

Answer 14

MMR vaccine contains live attenuated mumps virus; Is efficient in around 75% to 90% of cases

Question 15

True or False:

Mumps is easy to diagnose because of the swelling it usually causes somewhere.

Answer 15

False:

Detection is difficult because of the large number of asymptomatic cases

Question 16

What is meant by Togavirus?

Answer 16

Latin Toga = cloak, referring to virus envelope

Question 17

What is a Togavirus?

Answer 17

Enveloped (Class IV) ss(+) RNA virus arranged into an icozahedral capsid with spike-like, hemagglutinin-containing surface projections.

Question 18

True or Fasle:

Human; Rubella virus is the sole member of the Rubivirus genus

Answer 18

True

Question 19

Rubella is also known as ____ measles. and is ____ (more or less) contagious than measles.

Answer 19

German, less

Question 20

What is unusual about Rubella when compared to other Togaviruses?

Answer 20

Unlike most togaviruses, it is NOT arthropod borne

Question 21

Transmission of Rubella is ____ via droplet of respiratory secretions (multiplication in cells of the respiratory system; followed by viremia to reach target organs) and via ____.

Answer 21

Transmission of rubella is DIRECT via droplet of respiratory secretions (multiplication in cells of the respiratory system; followed by viremia to reach target organs) and via CONGNITAL INFECTION.

Question 22

True or False:

Rubella has 5 serotypes and is strictly a human infection.

Answer 22

False:

Rubella has 1 serotype but is strictly a human infection.

Question 23

What is the replication pattern of Rubella?

Answer 23

Replication in the nasopharynx and the lymph nodes: lymphadenopathy, followed by viremic (after 4-5 days) spread to target organs.

Question 24

About how long does the Rubella virus incubate in the nasopharynx?

Answer 24

Incubation period 12 to 23 days within the nasopharynx

Question 25

in Rubella after incubation, the infection usually lasts how long?

Answer 25

2-3 days

Question 26

What are the symptoms or Rubella infection?

Answer 26

With rare complication there are, pink diffuse rashes on the face, trunk, then limbs, due to accumulation of immune complexes under the skin

Question 27

What is meant when it is said a virus is Congenital?

Answer 27

Can be transferred to a unborn baby from an infected mother.

Question 28

Rubella congenital risk is important for how many weeks?

Answer 28

Important risk until the 20th week of gestation

Question 29

True or False: Congenital Rubella can cause a Systemic infection of the fetus leading to organogenesis disorders that jeopardizes the fetus development. and carries increased risk of abortion or post-natal death

Answer 29

True

Question 30

True or False: Clinical results are easy to obtain and can detect infection in 100% people.

Answer 30

False: Clinical diagnosis of rubella is unreliable, therefore, cases must be laboratory confirmed. Particularly for pregnant women.

Question 31

True or False: In regards to Rubella there is no specific treatment; just isolation of infected patients which can be difficult because of asymptomatic infections

Answer 31

True

Question 32

Women should avoid pregnancy __ days after vaccination with MMR or MMRV.

Answer 32

28

Question 33

What is a Parvovirus?

Answer 33

``` a naked (Class II) ss DNA virus with an icosahedral capsid *** negative and positive strand are packaged.*** ```

Question 34

What is meant by Parvovirus?

Answer 34

Latin parvus (small) referring to the size of virion

Question 35

When it is said Parvovirus is a Dependovirus, what does that mean?

Answer 35

Parvoviruses need a helper virus in order to replicate

Question 36

What is unique about Parvoviruses in their replication?

Answer 36

They only infect cells that are going through the cell cycle and that undergo DNA replication so They are restricted to the dividing cells of the body: cells of the hematopoietic system and the fetus.

Question 37

What Parvovirus genus is important for humans?

Answer 37

B19

Question 38

What percentage of adults is B19 Seropositive?

Answer 38

65%

Question 39

True or False: B19 transmission occurs; - By respiratory route - Through blood is possible - Congenital (from mother to fetus)

Answer 39

True

Question 40

What are the five classical childhood exanthems?

Answer 40

measles, varicella, rubella, Roseola and Erythema Infectiosum (B19)

Question 41

B19 infection causes Erythema Infectiosum, What is that?

Answer 41

Erythema Infectiosum = Infectious rash.

Question 42

Since B19 virus replicates in erythroid precursor cells it can cause Aplastic Crisis. What is aplastic crisis?

Answer 42

B19 causes lysis of these erythroid precursor cells and transient loss of all erythrocyte precursors from the bone marrow, then reticulocytopenia which is variable neutrophils count

Question 43

B19 is Congenital and can lead to fetus death in which trimester (does not cause congenital malformations)?

Answer 43

1st

Question 44

Which two of the common five diseases are caused by viruses belonging to Herpesvirus family?

Answer 44

Varicella and Roseola

Question 45

What is meant by Herpesvirus?

Answer 45

Latin from herpein (creep), referring to spreading of lesions

Question 46

What is a Herpesvirus?

Answer 46

Enveloped (Class I) ds DNA arranged linearly into a icosahedral capsid

Question 47

What are the 3 groups of Herperviruses divided into based on biological and phycical properties including cell tropism and genome organization?

Answer 47

Alphaherpesvirus, Betaherpesvirus, Gammaherpesvirus

Question 48

Which virus is within the Alphaherpesvirus that causes chicken pox or zosters (shingles)

Answer 48

Varicella-zoster virus (VZV)

Question 49

Which Betaherpesvirus cause Roseola?

Answer 49

Human herpesvirus 6A, 6B, 7

Question 50

Herperviruses contain a unique trait called Tegument, What is a Tegument?

Answer 50

The space between the envelope and the capsid is the tegument. This contains virally-encoded proteins and enzymes involved in the initiation of replication

Question 51

Since Herperviruses can be lytic or lysogenic, how does the virus determine which cycle to enter?

Answer 51

Viral DNA is transcribed by the cellular DNA-dependent RNA polymerase and regulated by viral-encoded and cellular nuclear factors

Question 52

True of False: Herperviruses can form syncytia which allow cell to cell transmission?

Answer 52

True

Question 53

VZV causes what two major diseases?

Answer 53

- Chickenpox (Varicella), usually in childhood (varicella was confounded with smallpox until the 19th Century) - Shingles (Zoster), later in life. Shingles is a recurrence of an earlier varicella infection. Recurrence in 10%- 20% of cases

Question 54

What is the incubation period of VZV and how is it transmitted?

Answer 54

Incubation: 2 -3 weeks | Transmission of VZV through airborne droplet (respiratory route) and direct contact with vesicles

Question 55

True or False: Chickenpox (varicella) is; highly infectious with Primary symptom of fever, sore throat, myalgia

Answer 55

True

Question 56

Chickenpox (varicella) has to stages of Viremia, what happen in each stage?

Answer 56

Primary viremia: The virus spreads from the lungs to lymphocytes and monocytes and to the reticulo-endothelial system. Secondary viremia occurs 5 days later, the virus travels to the skin, mouth, conjunctiva, respiratory tract

Question 57

VZV is ____ (more or less) deadly the older a person?

Answer 57

More

Question 58

What is Zoster and does it have a treatment?

Answer 58

Is a reactivation of VZV infection after many years of latency May be treated with acyclovir (antiviral nucleotides analogues)

Question 59

How common is Human herpesvirus 6A, 6B, 7 (HHV6&7)?

Answer 59

Worldwide, found in the saliva of the majority of adults (>90%) All children infected by the age of 2, life-long immunity

Question 60

What symptoms does Human herpesvirus 6A, 6B, 7 (HHV6&7) cause in children?

Answer 60

Symptoms include fever and upper respiratory tract infection and lymphadenopathy, lasting few days after an incubation period of 14 days.