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168 SEcTioN ii Microbiology ` microbiology—Virology Microbiology ` microbiology—Virology

Negative-stranded Must transcribe ⊝ strand to ⊕. Virion brings Always Bring Polymerase Or Fail Replication.
viruses its own RNA-dependent RNA polymerase.
They include Arenaviruses, Bunyaviruses,
Paramyxoviruses, Orthomyxoviruses,
Filoviruses, and Rhabdoviruses.

Segmented viruses All are RNA viruses. They include BOARding flight 382 in 10-12 minutes.
Bunyaviruses (3 segments), Orthomyxoviruses
(influenza viruses) (8 segments), Arenaviruses
(2 segments), and Reoviruses (10-12 segments).

Picornavirus Includes Poliovirus, Echovirus, Rhinovirus, PicoRNAvirus = small RNA virus.
Coxsackievirus, and HAV. RNA is translated PERCH on a “peak” (pico).
into 1 large polypeptide that is cleaved by
virus-encoded proteases into functional viral
proteins. Can cause aseptic (viral) meningitis
(except rhinovirus and HAV). All are
enteroviruses except rhinovirus and HAV.

Rhinovirus A picornavirus. Nonenveloped RNA virus. Rhino has a runny nose.
Cause of common cold; > 100 serologic
types. Acid labile—destroyed by stomach acid;
therefore, does not infect the GI tract (unlike
the other picornaviruses).

Yellow fever virus A flavivirus (also an arbovirus) transmitted by Flavi = yellow, jaundice.
Aedes mosquitoes. Virus has a monkey or
human reservoir.
Symptoms: high fever, black vomitus, and
jaundice. May see Councilman bodies
(eosinophilic apoptotic globules) on liver
biopsy.

Rotavirus Segmented dsRNA virus (a reovirus) A . ROTAvirus = Right Out The Anus.
Most important global cause of infantile CDC recommends routine vaccination of
A
gastroenteritis. Major cause of acute diarrhea all infants except those with a history of
in the United States during winter, especially intussusception or SCID.
in day care centers, kindergartens.
Villous destruction with atrophy leads to
+
+
 absorption of Na and loss of K .

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