Tidbits about Ebola virus

Alexander Madama agmadama at ix.netcom.com
Tue Mar 21 00:02:50 EST 1995


Hi there folks,
	These tidbits are targeted towards "armchair" virologists. They 
are just for those seeking a little information about this thing for 
curiosity.

	The Ebola virus belongs to one of the 13 families of RNA 
viruses, the FILOVIRUSES, along with Marburg virus. Previously these two 
(Ebola and Marburg) were grouped under the RHABDOVIRUSES.
(the thirteen type of RNA viruses and examples of each are as follows:
	PARAMYOVIRIDAE - measles,mumps,parainfluenza,Sendai
	ORTHOMYXOVIRIDAE - influenza A,B & C
	CORONAVIRIDAE - coronavirus
	ARENAVIRIDAE - 	lymphocytic choriomeningitis,Lassa 
fever,Tacaribe virus complex
	RHABDOVIRIDAE - rabies
	FILOVIRIDAE - Marburg,Ebola
	BUNYAVIRIDAE - California encephalitis,sandfly fever,Crimean 
Congo hemorrhagic fever
	RETROVIRIDAE - human T cell leukemia I & II,human 
immunodeficiency viruses I & II
	REOVIRIDAE - rotavirus,reovirus,Californa tick fever
	PICORNAVIRIDAE - rhinovirus,poliovirus,ECHO 
virus,coxsackievirus,hepatitis A virus
	TOGAVIRIDAE - rubella,Western Eastern and Venezuelan equine 
encephalitis,Sindbis,Semlike forest
	FLAVIVIRIDAE - yellow fever,dengue,St. Louis encephalitis
	CALICIVIRIDAE - Norwalk agent
)

	Filoviruses are filamentous, enveloped, negative-strand, single 
stranded RNA viruses.
	The virus replicates in the cytoplasm of the infected cell.
	Microscopic analysis of infected cells show eosinophilic 
cytoplasmic inclusions. Large amounts of viruses are replicated in the 
host cell causing necrosis of the liver, spleen, lymph nodes and lungs.
	The virus causes severe hemorrhaging leading to edema, 
hypovolemic shock, and, possibly death.
	Marburg virus was discovered in Marburg, Germany when laboratory 
workers were infected by African green monkeys.
	Marburg virus infections have been reported in Zimbabwe and 
Kenya.
	Ebola virus was disovered in Zaire (giving name to one strain of 
Ebola- Ebola Zaire virus)
	Mechanisms of natural transmisson are unknown, but viruses have 
been known to be transmitted by accidental transmission accidental 
injections and contaminated syringes. Contact with body fluids may also 
cause infection.
	Symptoms of infection include:
		headache and myalgias
		nausea, vomiting, diarrhea
		hemorrhaging from multiple sites
	Death occurs in 90% of those infected within 10 days.
	Handling of these viruses requires level 4 isolation (very 
stringent)
	Both viruses can be grown in tissue cultures (Ebola requires 
animal innoculation because it causes death to the tissue culture).
	Viral antigens can be detected by direct immunofluorescence 
analysis.
	IgG and IgM antibodies to filovirus can be detected by indirect 
fluorescence antibody, enzyme linked immunosorbent assay or radioimmuno 
assay.
	Infected individuals should be quarantined and contaminated 
animals should be sacrificed.

The Ebola Zaire virus is deadly, no doubt about it. It has already shown 
itself to mutate into several varieties (luckily, some non-pathogenic to 
humans), but it can mutate into worse forms (picture an air-borne 
virus). This is definetly something to watch out for as Marburg and 
Ebola are not the only viruses waiting to be unleashed into the human 
populace.

I hope these tidbits are enlightening into the world of filioviruses. I 
recommend reading such books as "Textbook of Human Virology, 2nd 
edition" by RB Belshe, Mosby publications St. Louis for detailed 
information. Good luck to all.

Alexander Madama
New York College of Osteopathic Medicine

(BTW: lots of the info I used comes from "Medical Microbiology", PR 
Murray et al., Mosby publications and thanks to Dr. Larry Green here at 
NYCOM for his wonderful talks on virology)




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