Hello, I'm Robert Gallo.
I'm the director of the Institute of Human Virology at
the University of Maryland School of Medicine in Baltimore, Maryland.
I'm here to talk to you about the discovery of
human retroviruses and about how they cause disease.
I'll also discuss a bit of their epidemiology and clinical features,
but you'll hear better about that from subsequent speakers.
We'd like to go back to the beginning with you on what the climate was like in
the academic community in the 1970s when
my colleagues and I began looking for human retroviruses.
We believed that it was a worthwhile effort particularly
because of the development of
some new technologies that I'll come to talk to you about in a moment.
And also because of the widespread presence of retroviruses
in diverse species of animals particularly causing leukemia,
but also causing some other types of diseases.
But in the 1970s,
there began to be,
I would say the middle to the late 1970s,
a strong push against the possible presence of retroviruses in man,
even not only that they didn't exist but
that there were good reasons to believe they could not infect humans.
This was coming at the same time as
a real downsizing of the study of infectious diseases in the industrialized world.
The confidence had built to such an extent that departments of microbiology were
closed in the United States and some of the noted medical schools.
Things were going much more towards molecular medicine and it was thought that
the microbes were more or less the playground for molecular biologists.
But then we didn't have to worry about new and serious epidemic diseases.
Some evidence for that statement to the pressure to reduce and
even close the Center for Disease Control in Atlanta,
Georgia in the United States,
where serious epidemics or other toxins,
chemical or whatever were being studied.
It was felt that this kind of problem was to be
placed really in tropical disease institutes,
but that medical science need not have to worry very much about it.
This was a way it reminds me of
the past periods where epidemics serious diseases were forgotten.
For example, if you go back to the 1950s,
polio came as a surprise and there was a feeling that we could make our efforts more on
chronic degenerative diseases and that we had
conquered infectious diseases that were really important.
We had antibiotics, we had better understanding of public health, and so on.
And it seems that this occurs about every 25 years.
When you go back 25 years before polio,
we had the great influenza pandemic of 1918 1919 and again,
at that time it caught people by surprise.
And the same is true of course with HIV and the AIDS problem.
So, there was this same kind of feeling.
We forgot that epidemic diseases of serious nature can
come very suddenly and usually associated with a societal change,
as occurred at the beginning of the AIDS epidemic in some years before,
points I will come back to later in this discussion.
There was also a strong feeling that viruses did not
cause any cancer in men and that no virus did.
This would be the period of the late 1970s once again.
What evidence is there from that statement?
Well, there was The Virus Cancer Program of the National Cancer Institute in
the United States as well as
many groups in different parts of the world especially in Europe,
looking for viruses that cause cancer and trying
to study them if they thought they had candidate viruses.
In mid-late 1970s,
there were important meetings that essentially declared that
all human cancer was due to chemicals and
the minor role or a modest role for genetics and viruses didn't cause any human cancer.
So this was kind of the climate.
But by the late 1970s,
at the same time that these sentiments were expressed strongly,
there began to accumulate increasing evidence for the existence of viruses
that cause human cancer and soon there would be the discovery of retroviruses.
Well, let me go to the next slide to summarize what happened.