This site is 100% ad supported. Please add an exception to adblock for this site.

Measles, Mumps, Rubella


undefined, object
copy deck
What family does measles virus belong to? How many serotypes of measles are there?
*the paramyxoviruses
*there is only one serotype of measles
How is measles acquired?
Through inspiration of aerosolized droplets.
How long is the incubation period for measles? What symptoms are seen in a typical infection? What clinical sign is diagnostic?
*incubation period is 10-14 days
*symptoms include fever, cough & runny nose, rash that first appears on head and neck
*Koplik's spots - red lesions with white centers that appear on buccal mucosa
Name some complications of measles.
*giant cell or primary measles pneumonia
*secondary bacterial pneumonia
*subacute sclerosing panencephalitis
What persons are at risk for atypical measles? How does this condition present clinically?
*persons who received the killed vaccine between 1963-1967
*there is an atypical rash (w/o Koplik's spots) and often a serious pneumonitis
What is the structure of the measles virion and its genome?
*helical nucleocapsid with an envelope
*genome is one molecule of (-) ssRNA
Describe the proteins found on the envelope of the measles virus.
*H glycoprotein that has hemagluttinating activity
*F glycoprotein that has cell fusing activity...this protein must be cleaved by a host protease to become active
What causes the rash seen in measles? When might the rash not be seen?
It is due to cell-mediated immunity. Persons with compromised immunity may not display the rash.
What is the target of the neutralizing antibody in measles? Are maternal antibodies protective?
*antibody is directed towards the H glycoprotein
*maternal antibodies provide protection for 6 months, although they might interfere with vaccine
Why might a patient with measles have a concomittant infection with a second agent?
Measles is characterized by depression of CMI.
Acquisition of measles depends on close contact with infected persons.
False: the virus is able to survive for four hours outside the body so close contact isn't neccessary.
What is the biggest problem comcerning MMR vaccination in the US?
It is a live virus vaccine thus requires storage under refrigeration.
What family does mumps belong to? How many serotypes exist?
*there is only one serotype
How long is the incubation period of the mumps virus? What is the common clinical presentation?
*18 days
*swollen salivary glands (parotitis); 30% of all cases are subclinical
What complications can arise from mumps?
*asceptic meningitis
*involvement of epithelia in ovaries or kidneys
What glycoproteins are present on the envelope of the mumps virus?
*one with both with hemagglutinating (HA) and neuraminidase (NA) activity
*one with fusion (F) activity
How is mumps spread? When are infections more common?
*spread by aerosolized droplets
*peak in winter and spring months
What family does rubella belong to? What makes it unique among members of this family? Describe the structure of its virion and genome.
*most other togaviruses have an arthropod vector
*icosahedral nucleocapsid with envelope
*genome is one molecule of (+) ssRNA
Where in the host cell does the rubella virus replicate?
*in the cytoplasm
What is the incubation period of rubella? What is the clinical presentation?
*14-21 days
*rash, arthralgia...most cases are subclinical
What is the danger of rubella in a pregnant woman?
If the woman is non-immune, the fetus is at risk for congenital rubella syndrome which may cause spontaneous aboortion, hearing loss, cataracts, or persistent infection.
How is rubella transmitted? What time of year is it most common?
*aerosolized droplets
*springtime epidemics every few years

Deck Info