Okay.
Mhm.
Uh,
today we are deviating from oncology
just a bit,
and we're going to have a discussion on influenza.
The title is influenza.
This year and next,
the program will be moderated by Dr Vincent gonna head of
the Department of Epidemiology,
M.
D Anderson Hospital.
Dr.
Gonna
Thank you.
Today's topic influenza
is appropriate for two reasons.
First,
as we meet today,
we're in the middle of a
nationwide influenza outbreak
caused by the A Victoria strain.
And second,
there are some disquieting reports about the scattered
appearance of swine influenza around the United
States.
In humans,
this is the same strain which caused the great
influenza pandemic of
1918.
The question is being raised.
Can this strain enter the human
population again with the same disastrous
results?
Me to put this situation in perspective
for you,
we've gathered a panel of professionals who are
both knowledgeable about and
interested in influenza
in order of their
seating.
We have Dr
William Paul Gleason,
who is the epidemiologist for the
Research Influenza Research Center at Baylor
College of Medicine and an
associate professor in the Department of Microbiology.
Dr.
John Bea Arthur,
assistant professor of pathology at the
University of Texas Medical School and also
a member of the Department of Epidemiology.
Here it Anderson
Dr Robert MacLean is chief of the
department of Communicable Disease division
at the Houston City Health Department.
And Dr James Steele
is professor of environmental science at the
University of Texas School of Public Health,
is formally the chief of
veterinary affairs of the Department of Health,
Education and Welfare,
and also,
very specifically in relation of our topic.
Today is a consultant to the World
Health Organization on animal influenza.
Our format today will be short presentations by
each panel member and then a general discussion in
which we hope the audience will join us
by way of introduction.
I might say that
flu is characterized by a
sudden onset in a
population and in an
individual to the point of being
diagnostic for epidemics,
for the population and diagnostic for
an individual patient.
When the doctor hears about it
looking into the past for the
best description of the onset of flu,
I came across one
from the epidemic of 1905
Sir William Broadbent of England
told of one of his patients,
who drove in at one gate of the park
in perfect health and out of the
other prostrate with influenza.
Just about everyone can get influenza.
There is no socioeconomic boundaries.
The epidemic of 17
89 and
17 90.
It was 17 90 when it hit America.
We get the quote in the spring of
17 90 at which time George
Washington was rendered severely ill by
it.
I have one slide that
gives us an idea of how
the communicable disease center in Atlanta
follows the course of influenza
outbreaks.
Influenza continues to be the only infectious disease in
the nation,
which causes epidemic excess
mortality.
Since 1957
there are something in the neighborhood of
300,000 excess deaths
that have been associate ID with influenza
a mhm
on this slide.
The solid line is
the expected number of
deaths that we should
see in the United States
Over time.
Significant deviations are represented
by the dotted
line,
and
when pneumonia and influenza
deaths go be uh
beyond this dotted line here
they are said to have
gone above the epidemic threshold.
Looking at the cases occurring
this year,
mhm for the
Morbidity and Mortality Weekly Report of
January 17th
We found that the first cases of the
winter were reported at that
time in January,
the middle of January.
In less than two months,
cases have been recorded from all
states in the continental United States.
As of this morning,
influenza is characterized as being
widespread in the United States.
The incidents has peaked in the Northeast
and it is increasing in the Western states.
Deaths due to pneumonia and influenza,
as we saw in that chart have
increased and are above
the so called epidemic
threshold in all areas of the country at the present
time.
So that's where we are this morning.
First panel member that I'd like to
call upon to discuss some of the elements of
influenza is Dr Arthur.
Thank you.
Okay.
The disease that occurs
uncomplicated by any other infection
in human being is usually turned to primary
atypical pneumonia.
The influence of virus preferentially
invades the respiratory passages,
both those of the nasal pharynx,
the hyper pharynx as well as the trachea and
bronchi I,
and may eventually involve the lungs.
In the most severe cases,
sporadic cases of the
influenza pneumonia may have
something of the range of 1% mortality rate.
And during the great pandemics,
the mortality rate may go.
Asshole.
Aya's 3% of the people it's
estimated that various figures are could be
found,
but somewhere in the range of 10 to 15 million people
throughout the world died in the 1918 to
1919 Pandemic
persons of all ages,
maybe seriously involved in death
occurs in all all peoples.
But preferentially mortality occurs in
infants and cardiac patients and in
pregnant women,
although certainly healthy young adults
can be seriously involved and oftentimes die
with this disease.
Death,
when it occurs,
is usually due to a type of al Volare capillary
block and failure of diffusion of oxygen.
Sue the capital.
Remembering If
persons die with this disease and obviously
Onley,
those most severely affected,
uh,
go on to have their lungs reputed autopsy for
actual examination of them.
The lungs are markedly heavy,
and there's extensive oedema and hemorrhage
microscopically.
One confined some
inflammation within the Broncos,
but this may often represent a superimposed
infection,
and one of the problems of trying to make a
diagnosis histological e of any of the viral
pneumonias or the influential pneumonia,
specifically is the complication
of a superimposed bacterial infection.
One of the features that does go along with a viral
infection,
though,
is the change of the alvito lining cells
into a cute boy.
It'll type epithelium.
Normally,
these cells would be indistinguishable.
Such is in this area.
One cannot make out the lining al Baylor cells,
and then down in this region,
they're very enlarged.
There's a controversy over whether these are
metal,
plastic or hyper plastic.
But for whatever technical reason exists,
there is the marked thickening of the epithelial cells
lining the al Volare spaces.
And where the Al Baylor capitally wall should be a
relatively thin membrane like this.
There's the mark thickening,
with some fibrous tissue deposited in here and a
chronic inflammatory infiltrate.
So this is why a person has difficulty
exchanging oxygen and carbon dioxide.
Is this mark thickening of the wall and the thickening of the
individual cells?
Mhm.
And here,
a slightly higher magnification shows the mark
thickening these walls again.
If one would accept that this should be about the normal
thickness of these Alvalade walls,
you see the very marked thickening that would go
on.
The histological picture is totally non
specific for most of the viral infections.
This one actually comes from a case of measles and
hear their giant cells that would show up.
But the other changes are non specific
and represent that a viral infection.
It's interesting that
the studies during the 1918 epidemic we're done
in part by a man named Goodpasture,
Goodpasture wrote to papers that were published
in 1919.
One of them had to do with 30 autopsies from young
men who were at the naval station at Chelsea,
just outside Boston.
And in these men.
He described the interstitial pneumonia and also
secondary pneumonias,
and his paper is very well illustrated in one
condensed English.
Even now,
looking at the paper,
those patients that had a typical viral pneumonia and those
that had secondary bacterial infections.
His second paper has brought him or enduring
fame as a medical
person.
And in this paper he described only two
individuals.
But he had two men that he wanted described more
fully those cases where he said they were
bacteria logically sterile.
He could not find bacteria,
either in cultures or in tissue
sections,
and he described the very typical viral pattern in
both of these men.
One of whom died seven days after the onset of the
illness.
But the other,
he commented on,
did have an atypical appearance to
his lungs,
or rather,
his clinical course by running so long.
And he also had very atypical changes in the gloom Mary
Ally with a proliferated grammarian on
Fridays and extra dates in the going Merry Ally.
This pattern we now recognize as
what we turn Goodpasture syndrome and probably
this man had a different disease,
or at least a very atypical reaction to
the viral influenza.
And we now associate the deposition of
Highland membranes in both lungs and kidneys with
the entity called Goodpasture syndrome.
But the original paper that Goodpasture
describe this entity and was a person who we thought was a
victim of the flu.
It's also,
um,
I think should be interesting to recall that the
influence of virus was first identified and isolated
in 1933.
Yet in the same paper,
Goodpasture wrote,
I am convinced that this is a that this is
true and that the ideological factor is not any of
the numerous pathogenic micro organisms which have been
cultured from the lungs,
often in pure culture,
but then an unknown virus which produces the general
intoxication is the cause of the disease.
So I think Goodpasture has a
hallmark in the 1918 epidemic
by separating out a separate disease
unknowingly and also truly predicting that a
viral ideology would be found for this disease.
Thanks.
Dr.
Gleeson,
You have been watching influenza in
Houston.
What do you find?
And how do you find it?
Um,
Vince,
The influence of research center was established
here it Baylor College of Medicine about two years
ago,
and in the short period of its existence,
Houston community has had to
endure to influence epidemics.
And as you all are aware,
we're concerned about the possibility of
a third successive epidemic.
Uh,
I want to say parenthetically,
though,
that the Influence research center
has other charges
and the clinical epidemiologic observations
that I want to talk about for a few minutes today,
Uh,
one of the direction Dr.
Robert Couch.
Uh,
studies are taking place and looking at the
host response.
The immune response,
a protective response,
thio natural and experimental infections
with influenza and also looking at the response
to and the effectiveness off
various new vaccine
preparations which hold
some promise for some improvement
in our immunization
programs against influenza.
Well,
way.
Look here.
At the first slide,
you can see
on this map of the greater Houston
metropolitan area some of the sights of
surveillance for influenza like illnesses,
which have been established under the the
program of the Influence Research Center.
Now these centers include all of the neighborhood health
clinics.
Um,
they're part of the Harris County Hospital District
on and cooperating with
us in studies.
Here are the physicians manning these
clinics under the A community
medicine department at Baylor.
Uh,
it also includes Sentinel family physicians
in the Houston community who also culture
the patients that they see in their practice that might have
a federal respiratory illnesses.
Um,
there's extensive surveillance also at Ben
Taub in the pediatric,
both outpatient and inpatient
areas,
thes cultures,
air all brought to our laboratories
at Baylor and processed
for respiratory viruses.
Now,
last year,
just as the surveillance program was
initiated in the middle of December
of 74 influenza,
a virus was prevalent in the community and
this virus was found.
Thio have the energetic characteristics
off the influence of a Port Chalmers virus,
which had first been isolated in Australia in 1973.
And you can see that following a lull during the
Christmas holidays,
this virus set
did uhh establish a
foothold and produced a moderate outbreak here in the
Houston community.
The next slide,
we'll look at some of the parameters
of evidence that
influences present in the community.
And in these
endeavors we have the
collaboration off the
epidemiology group at the Houston City Health
Department under Dr Maclaine in providing us
information about public school absenteeism,
industrial absenteeism,
emergency room visits and such things.
And I think you can see that there was nothing very
impressive about the impact of
the Port Chalmers epidemic in some of these parameters.
In Houston last year,
there was just a slight suggestion of increased
absenteeism in public schools during the peak of the epidemic.
Industrial absenteeism here is evidence by
absenteeism,
and five of the large
department stores here in Houston
didn't really show us too much.
Emergency room visits to Bend Tab,
uh,
did not reflect any increase in visits.
There were probably some increase in pneumonia admissions
at the Medical Center hospitals.
The only real evidence
that influence was present I think
count from this elevation of
deaths attributed to influenza and pneumonia.
During that period,
you could see that there were four successive weeks when they were
12 or more deaths reported.
And this is definitely an unusual occurrence since
if you go back,
I look at the weekly occurrence of mortality for the previous
two years.
You'll see that there were only two weeks in that entire
period when there were as many as 10 deaths reported in a
single week and those were single scattered weeks.
So they have four successive weeks off 12
deaths or more.
I think,
uh,
and it does reflect the presence of influence and that
this was a significant though moderate
outbreak.
Um,
during the fall,
we screened a pool of
syrah.
These were actually collected from court bloods,
taken a JD hospital,
and we found,
as we might expected,
that 80% of the cord blood showed
that thes young females
that had experience with Port Chalmers
like virus,
and you'll see that almost 80% had antibodies
support Chalmers.
But we also screened these same sirrah
against the A Victoria.
An urgent this virus had
just then recently been reported again from
Australia and was reported to
show significant any energetic
variation from the strain that we had the
previous year.
And you could see that that only 40%
had any detectable,
uh,
antibody to the A Victoria String.
And we would
then feel that the population
wa susceptible to possible spread
of this virus.
But we were hoping that it has with Port
Chalmers,
which was first isolated 73.
It might take another year to get here,
and we've had some time to yeah,
dispense,
um,
vaccine specifically for this.
But a Z we'll see in the next
side this time was
not available to us because
about the middle of January again,
we began to see
some evidence in these parameters that I've
talked about of influenza activity in the community.
And sure enough,
virus isolation started showing up.
This was a very early and preliminary
look at this on
actually,
in Week five,
the number of proven
cases off influenza a
Victoria roast about 232
and in week six and seven and eight
were already,
uh,
approximately over 250
virus proven cases of influenza
on,
If you can remember the history,
Graham,
that I showed a minute ago.
This is already more than double
the number of isolates that we had last year
so that we think that this
probably is a very significant epidemic.
Well,
just Thio refresh
your memory about the some of those parameters I talked
about.
I'd like to just use this thing as an
outline in which discuss what's happened this year.
Already on weeks five and six,
public school absenteeism has been a
12% but then dropped in weeks seven
and eight down Thio 10 and 9%.
Uh,
really,
For the first time in three years that we've
maintained surveillance of industrial absenteeism,
there has been a peak,
uh,
in well,
not really a peak.
There has been a significant increase in absenteeism and in
absenteeism,
uh,
reported to be due to respond to our illness.
Uh,
in these department stores,
the reports are a
little late,
but that appears to still be
rising in week
seven.
Um,
emergency room visits.
I had been TOB again,
if not reflected,
really the amount of influence
activity in the community.
But I think this is because of the special role of
anti emergency Room in this community
and that it sees a great deal of
trauma and other types of problems.
So there isn't much room for acute respiratory disease to squeeze
in.
But way have
then added to this surveillance emergency room visits to the
memorial hospital system and in
memorial Hospital system.
We've seen an increase of visits.
Thio,
the emergency room of the four hospitals combined,
um,
which was running on average about
172 visits per day for
the five or six weeks preceding the epidemic,
and only 12% of the people seeking care then
reported in acute respiratory illness.
Uh,
by week seven,
this had increased to 217 visits
per day,
with 25% off people seeking care
reporting respiratory illnesses.
So I think that this,
uh,
setting then gives us a better indication of what's going on.
We've also seen a similar increase in the number of
visits to the General Pediatric Clinic Van
Top,
and in fact,
they had a peak record number of
Children seeking medical care there on
two Mondays ago,
when there were a total of 432 Children scenes in
a 24 hour period,
This is a great greatly in excess of
any previous numbers seen there.
We've also seen a pretty significant increase in the
money admissions to medical center hospitals.
In fact,
the numbers our people are being admitted
for lower respiratory disease has doubled
in the past two weeks and up to
about 80 per week,
four weeks,
seven and eight of this year.
No reporting of mortality
understandably lags so that
way have not yet seen a really
increase in reported mortality.
It takes some time for death certificates to filter into the health department.
But in Week eight,
for the first time,
there was an increase and there were 12 deaths reported that
week.
And I think we would have to expect that
the numbers will continue to grow in that
category.
As the reports come in,
I'd like to just briefly talk a minute about the age
distribution off viral logically proven cases
that we've seen.
And this sort of picture has
been seeing both in last year's epidemic in this year that in the early
weeks of the epidemic,
the majority of cases
are proven in Children and that
during the peak of the epidemic in the later weeks.
The age distribution shifts so that
the majority of cases are in adults.
And this represents our
original isolates during the first five weeks.
And are these
that we identified,
61% were in Children under 15 years of
age.
We made a quick tabulation of the eye slits for weeks
seven,
and we found that that this had reversed that.
Now,
uh,
60% of the eye slits are in individuals over
60.
We saw the same thing last year when in the early weeks of the
epidemic,
uh,
during the time that it was smoldering along,
70% of the isolates were in Children under 15,
and in the mid part of the epidemic,
approximately 50% were in people
over and above 15.
I think this is important because,
uh,
a sui look it not only
these figures on proven cases,
but school absenteeism and visit pediatric clinic.
We sense that there is
a rapid horizontal spread of the virus through
the community among school age
Children,
and now we're probably
experiencing the effects of then vertical
spread to both older and younger younger
individuals in the community.
And actually,
I think in the last few years.
A few weeks,
Um,
following the peak in school age Children,
we've seen more complicated cases,
and it's probable that there is more
mortality during that time.
Well,
just this untraditional Thio.
In anticipating some of the comments that Dr Steele
might make,
I would like to say that we recently
screened another 100 current
records Sarah from JD Hospital and we
included in the energy and the energy for the
swine influenza virus
on.
We found that exactly zero of
young adult females in the community have
antibodies to swine,
uh,
influenza virus right now in the Houston community.
So this,
I think,
underlines some of our concern about the possibility
of the spread of swine like viruses.
Thank you.
Dr.
Maclaine is responsible for
the health of the city of Houston when it comes to communicable
disease.
Dr.
Maclaine,
what's the situation and what are you going to do about it?
Well,
Vince,
in my experience there two times in the year
when the state and local health authorities get
involved in the influenza problem
one when they have thio when they
should the time when they have to
be involved,
is when they get that first call from a local news media
station in the community,
usually sometime in December or January.
I wanted to know why the managing editor
is out with what he says is the flu and is there a
virus going around the community?
I remember sitting down with Dr Couch two years ago when
they influenza center was initiated,
discussing what types of surveillance activities we could
strengthen and what types of activities could be
added to our local activities as a
result of their funding mechanisms.
And I made the not so facetious remark that you could probably
abandon all these activities and sit back and wait for that
first phone call to come in from a radio or television
station.
And I think Dr Couch now is a little bit on
my side,
since this,
uh,
again predictably occurred at about the
time these other parameters were beginning to show that flew
was president.
The community,
now the other time with existing resource,
is that we have available to control influenza.
That the health department should be involved is at a time when you
might conceivably make an impact
on the illness,
particularly from controlling serious morbidity and
mortality,
and that,
naturally,
is in the fall.
Each year,
the U.
S Public Health Service Committee Advisory Committee
on Immunization immunization Practices
produces with almost monotonous
regularity and similar similarity,
uh,
their annual flu prediction and recommendation
for vaccine administration.
And outside of changing the components of the
A or B,
strains in by violent or
Polly violent vaccines,
they have consistently recommended that these vaccines be
administered to high risk individuals.
And I won't bore you with who these
individuals are from a medical standpoint.
Yet when you look at it from a realistic point of
view,
Uh,
in 1974 it was estimated that they were
between 50 and 60 million high risk
individuals in the United States.
And yet only about 30 million doses of influenza
vaccine were produced and distributed.
Uh,
obviously then from time
zero,
you only have enough vaccine to protect half of your
high risk population.
Now,
from a practical point of view,
uh,
we also know that probably,
uh,
a significant if not a major
proportion of influenza vaccine.
Each year gets administered to low risk individuals.
Healthy factory workers,
uh,
in various employee health programs.
Uh uh,
closed populations such as the military
and UH,
perhaps athletic teams where it would be a
disaster if the basketball team it couldn't make it
on to the national championship because of
a now outbreak of influenza.
So we're faced with the problem that we have a
vaccine available.
It is probably about 70% effective in
reducing morbidity and mortality
if administered at the proper time of year.
But in this country today,
only a small fraction of the people that really ought to
be getting it are getting it.
And therefore,
I doubt whether vaccine distribution has had any
significant impact on controlling the
disease and those for whom it is intended
just as a,
uh,
for our own interest to look at a
relatively easily accessible,
high risk population in the fall.
Late fall November of 1974
we looked at nursing homes in the city of Houston.
Uh,
we surveyed 44 nursing homes to
determine the total number of influenza vaccine
administrations and,
more specifically,
the number administered Thio nursing home patients
65 years of age and older
43 nursing homes cooperated with the
study with reasonably reliable
data.
There were a total of 5287
patients that were surveyed,
2846 had
received vaccine,
which is 53.8%.
And there were 4800 and 34 patients,
65 years of age and older as a part of this
survey,
and only 56.2% of these had
received influenza vaccine in time.
Thio protect them for the what
was a Port Chalmers outbreak that
winter?
Uh,
as I said,
only 56.2% of a high risk group in
nursing homes have been vaccinated for nursing homes.
Only reported 100% vaccinated,
and there were six homes in which no vaccine
at all had been administered.
Now,
from a practical point of view,
is a public health physician.
If I had thousands of doses of flu vaccine
available to me,
I'm not sure I'd go galloping through nursing homes and
dispensing it to bed ridden patients.
That is a perhaps on a
cost benefit basis that would not be realistic.
What we have done in the health department,
with the few doses of vaccine we have had available for the
last two years have gone out to
ambulatory senior citizens feeding centers,
which are far part of a federal program in this
area involving mostly,
uh,
poverty level of senior citizens.
We have administered vaccine Thio
800 to 1000 of these each
fall as our resource is permitted,
Uh,
we have not as yet gathered
any data on impact are zero
conversion rates or so forth.
But at least we feel we're putting our vaccine
smaller amount that it is in an area where it
might be doing some good.
Our only other health department programs that have been
consistent has been an annual vaccination program
for ambulance attendants,
uh,
in in the Houston City Fire Department.
And of course,
we provide the vaccine to our chest clinics,
which treat COPD and tuberculosis
patients.
But outside of that,
uh uh,
what we do is but a drop in the bucket in
this community where there are close to
200,000 people.
Uh,
that might be considered high risk individuals at the present
time.
And as you are well aware,
federal programs such as Medicaid and Medicare
generally do not provide for preventive medicine.
I've had this complaint brought to my attention so many
times,
Doctor,
I can't afford the $30 it will take for me and
my husband to go to a private doctor to get our influenza
vaccine on.
The Medicare will not pay for it.
What am I supposed to do?
And I suppose the federal answer is Wait till you get
influenza and then you can send the bills through
Medicare and this government program will pay
for it.
If you happen to survive,
so much the better.
But I think this is a deficiency in our current
program.
I think the Center for Disease Control,
to my knowledge,
is spending an extraordinary amount of money
on surveillance activities.
But I see it the federal level
no push towards a
practical,
shall we say,
intervention type program where funds air
actually being made available through one resource or another
to reach the population that the federal government says
and has said needs to be reached every year and isn't
being reached so that I'll turn it over to
Dr Steele,
who is now at the School of Public Health.
On board is also a zai mentioned of
working with the World Health Organization as a
consultant for animal influenza.
Um,
to my mind has to be one of the people
who keeps his finger on the
pulse of veterinary affairs like no one else.
Probably in the world.
Uh,
it's particularly interesting here because,
uh,
we're talking about a virus that may go back
and forth between animals and humans
and,
uh,
right now of in
late winter and early spring,
we have to decide whether or not swine
influenza virus is going to
go back in the vaccine or whether we can ignore it
and say,
This is just a sporadic Dr
Steele.
Well,
that's a very difficult one to answer.
But one of the leading influenza
research men of our times,
Tommy Francis,
who was in Michigan,
was head of the Army immunization
activities for influenza throughout World War
two of many years thereafter.
And it was his recommendation that swine
a virus should be
incorporated in vaccine and
discussing it with Dr Glaser realized I
was recently in 1959.
It was still a part of the human vaccine given
to the civilian population.
If when the military dropped it,
I do not know for certain.
Now,
talk about the 1918 situation,
and I'll tell you that I'm old enough to remember it.
Not that I did any autopsies,
but I read a lot about it.
And in an article I published in
1959 I researched the literature to find
out when swine influenza first appeared,
and the best date that I can put on it is
September 1918
appeared in I'll was called Hog flu.
It was reported at the United States
Animal Uh Health Conference
in December in Chicago that year.
It appears that the disease then became
epizootic and continued to
explode late in the summer
early fall for the next 10 12
years,
until it took on a
more,
uh established character of
being a latent type of disease that
could be provoked by meteorological
changes.
Also,
by coming in contact with Demopoulos
organisms or pastorello s,
which are very common in animals and also
by physical provocations such as show opened,
Lewis demonstrated when they use calcium chloride in
there is a very interesting epidemic,
a logical cycle to the disease that Shope worked
out many years ago involving the lung,
worm,
lung,
worm,
eggs,
earthworms and swine.
Doing just a fair number of earthworms,
and this is one part of the cycle of the
virus remaining in nature.
But also it can be latent within the animal
and persist and have re occurring
epidemics or epizootic,
Uh,
during the chilly months,
uh,
thinking from September until March,
the disease apparently disappears soon as the warm weather
occurs,
Uh,
Aziz to its importance at the moment
today,
it's hard for me to evaluate.
I think studies that's going on in Baylor gonna be
more important or also c.
D.
C.
But it is of interest.
A study was made by Francis and
Davenport,
his group at Ann Arbor,
some years ago on the prevalence
of swine,
a antibodies in the human population in the
United States and even in the
report is very definitive that
practically anyone born before
1918 was carrying a
swine influenza a tighter after
1918.
This starts to decline,
although it remains relatively high in
rural populations that have constant exposure
to swine,
and I think this is probably still going on in our
rural populations.
But today you have to realize that only 5% of our
people are defined as living in
rural areas,
uhh!
Just to acquaint you with the numbers that are going on.
We produce something between 191
100 million pigs annually in the United States
on guard.
These are the ones that are at risk.
The disease is mild in swine.
So the vaccine that was developed
in the late 19 thirties early 19
forties,
which is a very effective vaccine,
is seldom used because the farmer will take the risk
of saying,
Well,
they get sick for a few days.
I just keep in the barn,
protect him from chilling factors.
Prevent pneumonia from occurring,
and pneumonia does occur.
Well,
then they get the usual penicillin struck tomatoes in combination
treatment,
which is a fantasy of practically all respiratory
diseases of animals.
Today,
uh,
the uh,
problem is largely confined to the
United States.
This is one thing that has always disturbed me,
another epidemic ologists that have
discussed this problem as they work from a world
point of view.
Why has this disease remained
constant in the United States,
southern Canada?
It's seldom appears outside.
There's a few reports of isolates from England,
a few from Scandinavia.
There's an unusual report from Czechoslovakia and
rats the Chinese
look forward in
they're swine has not
now as to susceptibility of swine.
They are susceptible to all of the human strains
of influenza,
the Asian of 1956 and I
have here before me the review that was published in
1959.
Discussing that and it's relation,
I had an article in their relation to animals
in the 1956 epidemic,
which originated,
as we define it today someplace in Eastern
Asia,
namely China.
A study or survey was made by two
British investigators to determine if this
disease that is the Hong Kong strain may have
originated in swine.
They were not able to come to any conclusion.
We at CDC at that time used the Hong
Kong and were able to produce a an
acute disease in swine and could recover
virus for some weeks after their
artificial exposure.
Looking to the future of
the possible reservoir of
animals as of influenza,
we have a very large study going
that is funded by N.
I H and,
uh,
in cooperation with the World Health Organization.
There is a center at the University of Tennessee under
uh,
Webster,
that is studying the interrelation of
all animal influenza viruses,
namely those found in birds.
There is an article and W H o chronicles for
December 1975 a beverage in which he
summarizes all the work that has gone on and
throughout the world.
Uh,
influenza a various,
uh,
stereotypes have been recovered from some
147 different species of birds.
Uh,
this includes citizen birds canaries.
Probably the most serious has been in Turkey's,
where some of the turkey EP in our ticks as they
refer to epidemics and birds have actually
wiped out flocks.
And what we're speculating on here is there is a
constant re combination because you
cannot attribute it thio mutant and
change.
The generations change so rapidly.
That is the neuron today's,
uh,
component of the virus that there
must be re combinations air going on.
And actually what we're looking at is nature's laboratory
of developing new strains of influenza.
And we're looking at it from a point of view,
that is,
a group of physicians and veterinarians and
Ecologists of when these re
combinations can occur that the
organism the virus will take on what is referred
to as a business and attach itself to
a mammalian host and eventually this
maybe man.
So,
uh,
we'll be at this for a long time to come.
And,
uh,
it is my feeling that,
uh,
the immunization committees should
restore the swine
influenza virus,
uh,
to the vaccine that is used in
man.
Thank you.
Turning to a more informal
panel type discussion,
ID like thio entertain questions from
the floors as well as from our other Panelists.
We do have microphones that can be
used if you would like to ask questions
and just raise your hand
and we can bring them to you of
to start off.
Though,
uh,
I'd like to ask the panel,
Uh,
is it generally agreed that this is now a re
combination factor for
viruses affecting man?
Or,
uh,
can we still,
uh,
say that maybe a mutation for,
um Well,
there's a great deal of interest in this
in this possibility.
And at the meeting in NH recently,
it was pointed out that if re combination
does occur in nature,
that the situation recently reported Fort
Dix probably represented an ideal
circumstance because to get
viruses,
influence,
viruses,
thio share and intermix there
important and urgent,
particularly the hemagglutinin in their men today.
Sanderson's You usually mix them in
culture and
suppressed the growth of one of the donors
with antibody and
then allow them both to grow within the
same tissue
culture.
Uh,
system.
Uh,
as you're aware,
in the military,
all recruits receive vaccine when they
report for duty.
So these recruits had received
three currently available vaccine which
waas the Port
Chalmers Imagine.
But of course,
which has some cross ranking antibody to Victoria,
and
so this made them partially immune.
Thio the a victorious strain
on this,
by the way,
is a unique situation,
since this is the first proven instance
where to energetically
distinct influenza.
A viruses have been found to be prevalent in the
same population at the same time
because they have identified
both human cases off a
Victoria infection and the
A swine like
virus infection in the
Fort Dix military people in the same
period.
And as far as we know,
this is the first instance of really
well,
at least since we've been able thio isolate
the flu virus.
The first instance off Swine virus is
spreading by human to human
contact.
There's certainly a lot of itself swine to human
infection.
But there's no real evidence off human to human
spread of swine like viruses
prior to this this recent
Fort Dix outbreak.
So this situation then does represent a
situation where recombination may have occurred in
nature,
I have to say,
though,
this is just one of the hypotheses
now current about the emergence of
new strains off our energetically distinct
strains of influence.
A Fires ID
take issue with any re combination of the
swine virus because from what I
understand,
the original isolate in 1932 and comparing it with
the annual isolates that they come up on Easter
Day at University Wisconsin is more or less the center for all this
for the Americas.
And the anti genic shift has been of such a slight
nature that you can actually say it's probably the way the
technicians handled the material.
That's true for swine virus.
The swine virus has been energetically
stable,
the swine hemagglutinin that the isolate now is very
similar to the swine hemagglutinin of the original.
I slipped back in 1931 but one thing I
didn't add to my,
uh,
there has been four different isolations now.
I just checked with C D.
C before I came over here and also with Beaumont
Hospital.
That's the first appearance in Texas.
There's three soldiers have been diagnosed
as having swine like influenza or,
uh,
Beaumont Hospital.
El Paso.
There's one at,
uh,
University of Tennessee in a man working
in an abattoir who has Hodgkin's disease.
There's two at the University of Virginia
Hospital at Charlottesville,
and the 12th one has appeared at Fort Dix
from that what do you think?
Uh,
Dr Steele,
what do you think,
uh,
could cause a virus to come from an animal
reservoir back into a,
uh,
human population.
When you consider that this has been the same
virus,
it's been in the swine population the whole
time.
Why are we worrying about it now?
Why do you think that there's a,
um,
certainly,
if,
uh,
if you have 30% of the
population susceptible,
you should be able to get it to catch.
Do we need to wait for 80% for it to
transfer over?
Well,
I think it's the kind of thing that Francis and his
colleagues postulated that as the herd
immunity talking about human population as a
whole declines that there is an increasing number of
susceptible,
and within that susceptible population there,
there are individuals that are more
susceptible site.
These two Hodgkins cases,
or I didn't cite there was one Hodgkin's case
that died last year at Mayo's,
which was the first death that I know is
attributed to the swine influenza virus.
During my professional career,
we've talked a lot about being exposed to it,
but that was the first death.
And,
uh,
I don't believe there
is their death at Fort Dix or not
because I've heard it both ways.
Yes,
there was one veil case of Fort Dix,
right?
And when I talk about recombination,
though,
what we're really hypothesizing is
that a and influenza virus
strain with human violence factors,
whatever that ISS acquires,
the hemagglutinin neuraminidase of the
swine virus.
That's that's what the hypothesis
says that happened that that the human
violence factor may have been provided by the A
Victoria strain prevalent at Fort Dix
and it acquired than the swine,
including Norman.
Today's,
of course,
which is completely different from the
hemagglutinin.
And there are many days indigents,
which are currently on influenza strains.
The Victoria strain another strange.
So this and this is,
of course,
the first time that we've We've seen a
a reversal of prevalence of a of
return of a previously
prevalent imagine because this the Norman
today's engine,
which is present on this swine like virus,
is very similar,
if not identical to the neuraminidase managing that
was seen on all influences.
Straight strains isolated in this country prior to
1957 1957
Asian epidemic then represented a complete shift in the Norman
today.
Sanity,
uh,
human gluttons.
Of course,
there have been three or four others in the interim.
I can't resist one last facetious question
directed at Dr Steele when I was in ST Louis at the
immunization conference this week,
Dr Michael Greg agreed with you that
future influenza vaccine
should contain an a swine component.
And he went on to say that it was his personal gut
reaction that the majority,
if not uh,
all of the American population should be
immunized with a swine containing
vaccine components.
And with 220 million people in the United States
today,
would it be more practical to try to immunize
220 million people with a swine.
Or would it be of any benefit to go after
150,000 hogs?
Yeah.
Uhh!
Not the hog issue.
I can sell.
Sell you right now that the
swine vaccine never sold in Peoria.
E think that
might be a good note,
but there's another one.
Or tow a close.
There's another about a minute more time.
I just want to cite one other example of where
we thought we were going to get into some deep trouble.
When equine influenza first appeared in
1966 with the Prague strain,
this was an influenza A and naturally,
there were reports that people were crime currently
ill with that and then in the Miami
strain,
which appeared in 1963.
And if it hadn't been for the Euro Amadeus
difference with the equine to strain
or the Miami strain,
we would have thought that was Hong Kong that have gotten into the
horses.
And this is a very serious problem when the states can't collect
their taxes from the horse races.
Well,
we've seen a number of reasons why influenza can be
important.
Thio uh,
man and society
I'd like to bring the session to a close.
I'd like to express our thanks to our panel
members for being with us today.
And I'd like to thank you for listening.
You're gonna celebrate in New York?