Lecture 9Medicine United Group

1425 -1426

Reoviridae

Three of nine genera contain human viruses.

  • Rotavirus (infect human)
  • Coltavirus
  • Orthorevirus

Rotavirus:

In 1973 a new virus was discovered in Australia, first in duodenal biopsies then in fasces of Melbourne children with gastroenteritis. Electron micrographs revealed viron with unique appearance (rota=wheel).

Caliciviridae

The family derives its name from the 32 cup shaped (calix, cup) surface depression that give the virus it unique appearance. Calicivirus genus include hepatitis E and human Caliciviruses.

Astroviridae

Astrovirus is the only genus under this family and can causes infection to human. This virus described in 1975 when they were observed by EM in the faeces of children with diarrhea.

  • RNA Virus

NB:

The only difference between Calicivirus & Astrovirus is throughout the Lab diagnosis.

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Lecture 9Medicine United Group

1425 -1426

Virus / Transmission / Disease / I.P / Symptom & Sign / Infectivity / Clearance / Lab diagnosis / Prevention &Control
Rotavirus / Fecal oral route / Gastroenteritis / 1-3 days / Diarrhea, fever, nausea & vomiting / Fromonset of symptom until 1 week after illness / No latent or chronic carrier state. / Specimen:
  • Stool
  • Serum
Technique:
  • EM, Latex agglutination (not sensitive)
  • PCR
/ No vaccine
Calicivirus / Fecal oral route / Gastroenteritis / 1-3 days / Abdominal pain (differential diagnosis), diarrhea, nausea & vomiting / During clinical illness / Same as above / Same as above / No vaccine
Hepatitis E / Fecal oral route / Acute icteric hepatitis / 15-60 days
(because its systemic infection) / Abdominal pain, vomiting, fever, arthralgias, jaundice / During acute illness / Unknown / Specimen:
  • Stool
  • Serum
Technique:
  • IEM (Immune electron microscope), ELISA, western bolt.
  • PCR
/ No vaccine
Astrovirus / Fecal oral route / Acute diarrhea disease / 3-4 days / Vomiting, fever, diarrhea, Abdominal pain / During clinical illness / No latent or chronic carrier state / Specimen:
  • Stool
Technique:
  • IEM, Elisa
  • Cell culture
/ No vaccine

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Lecture 9Medicine United Group

1425 -1426

Filoviridae

There are 2 genera in this family:

  1. Mabrug virus genus.
  2. Ebola like virus genus.

Mabrug virus was identified in humans who died after they handled African green monkey kidneys to produce cell cultures the monkey came from Uganda and the laboratories were in Marburg-Germany.

Ebola virus :

It was first isolated during 1976 epidemic of sever hemorrhagic fever in ZaireSudan.

1

Lecture 9Medicine United Group

1425 -1426

Virus / Transmission / Disease / I.P / Symptom &sign / Infectivity / Clearance / Lab diagnosis / Prevention &Control
Marburg / Zoonosis then infection spread by intimate contact / Hemorrhagic fever / 4-10 days / Fever, headache, muscle pain, diarrhea, vomiting & maculopapular rash / No latent phase / Unknown / Specimen:
  • Serum.
Technique:-
  • Cell culture.
  • EM
  • IFA, FA
  • PCR
/ No vaccine
Note : we can use Ribavirin(but unsuccessful level)
Ebola / Same as above / Same as above / 4-10 days / Same as above / No latent phase / Unknown / Same as above / Same as above

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