Flashcards in deck_524014 Deck (130)
review of structure of paramyxoviruses- enveloped?- nucleocapsid symmetry?- genome structure?- -/+ stranded?
enveloped virionhelical symmetrygenome consists of a single molecule of RNARNA genome is minus-stranded
what type of virus are mumps and measles?
are mumps and measles antigenically related to parainfluenza viruses?
mumps ismeasles is not
describe mumps and measles:- nucleocapsid- genome- +/-- envelope?
helical nucleocapsidminus-stranded RNAenvelope with virus-specified glycoproteins
do mumps and measles hemagglutinate red cells?
do paramyxoviruses carry an RNA polymerase?
can measles and mumps viruses reassort? why or why not?
since the RNA is only one piece, genetic reassortment is impossibleas a result, no significant antigenic variation has been seen
what types of infections do mumps and measles (and paramyxoviruses) cause?
systemic infections with viremia as an essential step in pathogenesis
what is an essential step in the pathogenesis of mumps and measles
what kinds of infections do orthomyxoviruses and paramyxoviruses generally cause?
local, nonsystemic noviremic infections
what is the significance of the fact that mumps and measles cause systemic infection (summary)?
incubation period is longer for mumps and measles because cycles of multiplication in several sites in sucession are requiredlifelong immunity occurs in individuals who have had the disease - obligatory viremia allows neutralization by IgG
how does the incubation period of mumps and measles compare with that of orthomyxoviruses and paramyxoviruses (so flu and paraflu)?
it's longer because the cycles of multiplication is several sites in succession are required to establish infection in mumps and measles
how long is immunity to mumps and measles after infection?
what antibody type is involved in the reaction to mumps and measles?
obligatory viremia allows for neutralization by IgG
how many serotypes of mumps are there?
how many types of species can mumps infect?
humans are the sole reservoir of mumps
how is mumps transmitted?
by respiratory droplets
how long is the average incubation period of mumps before symptoms appear?
what are the symptoms of mumps? what would allow you to diagnose mumps (ie what would you look for)?
around 18 days, a prodromal period of fever, malaise, and anorexia is followed by unilateral or bilateral swelling of the parotid gland (parotiditis) = usual presenting clinical symptomwill have inflamed parotid duct (stensens duct) in mouthalso get orchitis in males after age of puberty
what is paratiditis
caused by mumpsinfection of the parotid glandthe virus grows in the enlarged parotid salivary glands becomes painfulis excreted in saliva several days before and after swelling of the gland begins
why does mumps cause pain?
pressure and swelling within organs in tight capusles, so ones like the parotid gland and testis (orchitis) after puberty
are most mumps infections symptomatic or asymptomatic?
most are symptomatic - only 30% are subclinical/asymptomatic
where does mumps virus multiply, primarily?
in respiratory epithelium and local lymph nodes
what is the result of primary mumps multiplicaton (ie what's the secondary step in infection)?
in viremia that spreads to the salivary glands and other organs
where do most of the infectious virions in mumps come from?
they are produced in the salivary glandsthey go down the duct to the mouth and are spread by coughs and sneezes
how long does it take for parotiditis to begin in a mumps infection?
about 18-21 days = a three week incubation period
how frequent is orchitis in mumps infections?
occurs in about 30% of infected males past puberty
what is orchitis?does it resolve?who can get it?
painful inflammation of the testiclescaused by mumpsunilateral orchitis resolves with no other complicatoinsbilateral can result in sterility or subfertility but this outcome is uncommononly in adults after puberty because children don't have fibrous capsule yet
what organs are affected by mumps?
testicles, parotid glanduncommonly the pancrease and ovarymore commonly the meninges (aseptic meningitis)all have a generally benign course