Ask A Scientist© Biology Archive

 
Question:  What is the deadliest virus ever?
Bobbi J Niswender
 
 Answer 1:
     It depends on what you mean by deadliest.
     If you mean the virus that has the highest chance of killing you
if you get it, I'd say the Human Immunodeficiency Virus (HIV)---the
virus that causes AIDS. So far, it looks like almost everybody who
gets HIV will die of AIDS, though they can often remain healthy for
many years before that happens. Next worst is probably the virus called
Ebola. Depending on which type of Ebola it is, over 90% of the people who
get it die. Fortunately, Ebola seems very very rare.
     If by deadliest you mean the virus that has killed the most people,
I'd say either the bubonic plague or HIV, but HIV is still increasing,
while bubonic plague is not.
     If by deadliest you mean the "worst" virus---I'd say the class of
viruses called filloviruses (Ebola is one type of fillovirus). They are
usually very deadly (less than 10% survive), and are transmitted very
easily---by air, by touch, that sort of thing. Fortunately, they're
very rare.
David DeGusta
 
Answer 2:  I agree with most of the previous answer but I would say that influenza 
kills more than any other virus.  Millions were killed in the epidemic
of 1918 if memory serves me correctly.  Ask your great grandparents to
see if they remember the fear of that year.  Certainly thousands are killed
yearly, but mostly elderly and immunocompromised fall prey.  If you call your 
local health department, they may provide you with accurate numbers.  Also, the 
bubonic plague is caused by the bacteria Yersinia pestis.  This disease is generally 
carried by rodents and occurs occasionally in this country in the west and is endemic in
parts of the world where animals such as rats are worshiped.  There
was an outbreak in India last year because of a high rat population in
close contact with people.
Good Luck with Science!
Michael B Lomonaco

Update: Plague reported among a population of prairie dogs but no
spread to humans yet.  Follow your newspaper.
Michael B Lomonaco