leftover viruses (enteroviruses, mumps, adenoviruses, parovirus B19) Flashcards
enteroviruses
enveloped/nonenveloped:
capsid shape:
genome:
enteroviruses
enveloped/nonenveloped: nonenveloped
capsid shape: icosahedral
genome: + ssRNA
enterovirus subenera (5)
1) polio virus, 1-3
2) Group A coxsackieviruses, 1-24
3) Group B coxsackieviruses, 1-6
4) Echoviruses, 1-34
5) a bunch with no subgenus, but just a type #
transmission of enteroviruses
1) fecal oral (like polio)
2) respiratory
3) both
* transmission can be direct or indirect (fomite, water, food)
pathogenesis of enterovirus?
1) infect mucosa and associated lymphatic tissue of GI or respiratory route —> minor viremia
2) next infect reticuloendothelial system of liver, spleen, bone marrow —> major viremia
3) spread to other organs —> specific manifestations
The manifestations of enteroviral infections discussed, and the subgenera typically associated with them.
1) Polio
2) aseptic (viral) meningitis
3) group A coxsackieviruses: exanthems (rashes) and enanthems (mucosal lesions)
4) group B coxsackieviruses: myocarditis, pericarditis
90% of aseptic (viral) meningitis are caused by?
enteroviruses
when does viral meningitis, caused by enterovirus, typically occur?
late spring through fall in temperate climates
peak ages for viral meningitis?
<1 yo and 5-10 yo
how long does it usually take to recover from aseptic meningitis caused by enterovirus?
3-7 days
exanthems (rashes) and enanthems (mucosal lesions) are usually caused by which enterovirus? in who? how long is the recover?
group A coxsackieviruses
in children, 3-10 yo
recovery: 7-10 days
manifestations of hand-foot-mouth disease. What causes it?
fever and lesions on buccal mucosa, tongue, hands, feet and buttocks
- caused by enteroviruses, especially group A coxsackieviruses
manifestations of herpangina? what causes it?
ever, vesicles on fauces and soft palate
- caused by enteroviruses, especially group A coxsackieviruses
which enterovirus causes myocarditis and pericarditis?
group B coxsackieviruses (and many other viruses)
manifestations of myocarditis
fever, chest pain, dyspnea, arrhythmia, rarely heart failure
pericarditis manifestations
sharp stabbing chest pain exacerbated by lying down and deep breathing, fever. Rarely leads to constrictive pericaditis or cardiac tamponade
how is enterovirus diagnosed?
usually syndromic diagnosis
if the detection of the virus is important: PCR is the most sensitive and specific, but it’s very expensive. Culturing has generally low sensitivity, and there are no immunoassays
treatment and prevention of enterovirus infections?
1) supportive txt– there are no effective antivirals for enterovirus
2) polio is the only enterovirus for which there’s a preventative vaccine
how is mumps transmitted?
respiratory droplets/saliva via direct or indirect (fomites) contact
pathogenesis of mumps
1) virus replicates in respiratory epithelium, leading to viremia
2) then infects the parotid glands and variable other sites (CNS, testes, ovaries, etc)
salivary glands infected with the mumps show…
interstitial edema with a serofibrinous exudate and mononuclear infiltrate
incubation period for mumps
16-18 days
manifestation of the mumps
nonspecific prodrome w/fever/malaise
pt complains of earache and pain with palpation of parotid gland, followed by swelling of gland and constant pain
- the 2nd parotid gland ins involved in 75% of cases and the submaxillary salivary gland is involved in 10% of cases
how long does it take for mumps to resolve generally?
7-10 days
2 more common complications with mumps
- orchitis in 30-40% of post pubertal men (frequently bilateral, sterility = rare)
- aseptic meningitis in 10% of adults (less common in kids)
5 rare complications of mumps
- hearing loss (children)
- encephalitis
- fetal loss in 1st trimester
- oophoritis
- pancreatitis
diagnosis of mumps is made by:
symptoms and exposure history. confirmed by serology (IgM or acute and convalescent titers), or detection of virus in saliva by culture or PCR)