One of the first patientsI had to see as a pediatrician was Sol,
a beautiful month-old baby
who was admitted with signsof a severe respiratory infection.
Until then, I had never seena patient worsen so fast.
In just two daysshe was connected to a respirator
and on the third day she died.
Sol had whooping cough.
After discussing the case in the roomand after a quite distressing catharsis,
I remember my chief resident said to me,
"OK, take a deep breath, wash your face,
and now comes the hardest part,
we have to go talk to her parents."
At that time, a thousand questions came to mind,
from: "How could a one month-old baby be so unfortunate?"
to: "Could we have done something about it?"
Before vaccines existed,
many infectious diseaseskilled millions of people per year.
During the 1918 flu pandemic
50 million people died.
That's greaterthan Argentina's current population.
Perhaps, the older ones among youremember the polio epidemic
that occurred in Argentina in 1956.
At that time, there was no vaccineavailable against polio.
People didn't know what to do.They were going crazy.
They would go painting trees with caustic lime.
They would put little bags of camphor inside their children's clothes
as if that could do something.
During the polio epidemicthousands of people died.
And thousands of people were left with very significant neurological damage.
I know this because I read about it,
because thanks to vaccinesmy generation was lucky
to not live through an epidemicas terrible as this.
Vaccines are one of the great successesof the twentieth century's public health.
After potable water,
they are the interventionsthat have most reduced mortality,
even more than antibiotics.
Vaccines eradicated terrible diseases such as smallpox from the planet
and succeeded in significantly reducing mortality
due to other diseases such as measles,
whooping cough, polio and many more.
All these diseases are considered
vaccine-preventable diseases.
What does this mean?
That they are potentially preventable,
but in order to be so, something must be done.
You need to get vaccinated.
I imagine that most,if not all of us here today,
received a vaccineat some point in our life.
Now, I'm not so sure that many of us know
which vaccines or boosters we should receive after adolescence.
Have you ever wonderedwho we are protecting
when we vaccinate?
What do I mean by that?
Is there any other effectbeyond protecting ourselves?
Let me show you something.
Imagine for a moment
we are in a city
that has never had a caseof a particular disease,
such as measles.
This would mean that in this city no one has ever had contact with the disease.
No one has either the natural defenses against, nor been vaccinated against measles.
If one day, a person sick with the measlesappears in this city
the disease won't find much resistance
and will begin spreadingfrom person to person,
and in no time it will disseminatethroughout the community.
After a certain time
a big part of the population will be ill.
This happened when there were no vaccines.
Now, imagine the complete opposite case.
We are in a city
where more than 90 percentof the population
has defenses against measles.
It means that they've had the disease,and have developed natural defenses.
They either survived, or were immunized against measles.
And one day,
a person sick with the measlesappears in this city.
The disease will find much more resistance
and won't be transmittedthat much from person to person.
The spread will probably remain contained
and a measles outbreak won't happen.
I would like youto pay attention to something.
People who are vaccinated
are not only protecting themselves,
but by blocking the disseminationof the disease
within the community,
they are indirectly protectingthe people in this community
who are not vaccinated.
They create a kind of protective shield
which prevents then from coming in contactwith the disease,
so that these people are protected.
This indirect effect of protection
which unvaccinated people havewithin a community,
simply by being surroundedby vaccinated people,
is called herd immunity.
Many people in the community
depend almost exclusivelyon this herd immunity
to be protected against disease.
These people displayed in infographicsare not just hypothetical.
These people are our nephews,our children,
who may be too youngto receive their first shots.
They are our parents, our brothers,
our acquaintances,
who may have a disease,
or receive medicationwhich lowers their defenses.
There are also peopleallergic to a particular vaccine.
They could even be among us,
any of us who got vaccinated,
but the vaccinedidn't produce the expected effect,
because not all vaccinesare always 100 percent effective.
All these people depend almost exclusively
on herd immunityto be protected against diseases.
To achieve this effect of herd immunity,
it is necessary that a large percentageof the population be vaccinated.
This percentage is called the threshold.
The threshold depends on many variables.
It depends on the germ's characteristics,
and those of the immune responsethat the vaccine generates.
But they all have something in common.
If the percentage of the populationin a vaccinated community
is below this threshold number,
the disease will beginto spread more freely
and may generate an outbreak
of this disease within the community.
Even diseases
which at some point were controlledmay reappear.
This is not just a theory.
This happened and is still happening.
In 1998, a British researcherpublished an article
in one of the most importantmedical journals,
saying that the MMR vaccine,
which is given for measles,mumps and rubella,
was associated with autism.
This generated an immediate impact.
People began to stop getting vaccinated,and stop vaccinating their children.
And what happened?
The number of people vaccinated,
in many communities around the world,fell below this threshold.
And there were outbreaks of measlesin many cities in the world.
In the U.S., in Europe.
Many people got sick.
People died of measles.
What happened?
This article also generated a huge stirwithin the medical community.
Dozens of researchers began to assessif this was actually true.
Not only could no one find
a causal association between MMRand autism at the population level,
but it was found that this articlehad incorrect claims.
Even more, it was fraudulent.
It was fraudulent.
In fact, the journal publicly retracted
the article in 2010.
One of the main concerns and excusesfor not getting vaccinated
are the adverse effects.
Vaccines, like other drugs,
can have potential adverse effects.
Most are mild and temporary.
But the benefits are always greater
than possible complications.
When we are ill,
we want to heal fast.
Many of us who are here
take antibioticswhen we have an infection,
We take anti-hypertensiveswhen we have high blood pressure;
we take cardiac medications.
Why? Because we are sickand we want to heal fast.
And we don't question it much.
Why is it so difficultto think of preventing diseases,
by taking care of ourselveswhen we are healthy?
We take care of ourselves a lotwhen affected by an illness,
or in situations of imminent danger.
I imagine most of us here,
remember the influenza-A pandemic
which broke out in 2009in Argentina and worldwide.
When the first casesbegan to come to light,
we, here in Argentina,were entering the winter season.
We knew absolutely nothing.
Everything was a mess.
People wore masks on the street,ran into pharmacies to buy alcohol gel.
People would queue up in the pharmaciesto receive a vaccine,
without even knowingif it was the right vaccine
that would protect themagainst this new virus.
We knew absolutely nothing.
At that time, in addition to doingmy research scholarship
at the Infant Foundation,
I worked as a home pediatricianfor a prepaid medicine company.
I remember that I startedmy shift at 8 am
and already I had a listof 50 scheduled visits.
It was chaos,people didn't know what to do.
I remember the types of patientsthat I was examining.
The patients were a little olderthan what we were used to see in winter,
with longer fevers.
And I remember I told my research scholarship mentor,
and he, for his part, had heardthe same from a colleague,
about the large numberof pregnant women
and young adults
being hospitalizedin intensive care,
with difficult to manage clinical profiles.
At that time,we set out to understand
what was happening.
First thing Monday morning, we took the car
and went to a hospitalin Buenos Aires province,
that was supposed to bea referral hospital
for cases of the new influenza virus.
We arrived at the hospital; it was crowded.
All health staff were dressedin NASA-like bio-safety suits.
We â with face masks in our pockets.
Being a hypochondriac,I didn't breathe for two hours.
But we could see what was happening.
Immediately, we started reaching outto pediatricians
from six hospitals in the cityand the Buenos Aires province.
Our main goal was to find out
how this new virus behaved in contact with our children,
in the shortest time possible.
A marathon work.
In less than three months
we could see what effectthis new H1N1 virus had
on the 251 childrenhospitalized by this virus.
We could see which childrengot more seriously ill:
children under four,especially those less than one year old;
patients with neurological diseases,
and young childrenwith chronic pulmonary diseases.
Identifying these at-risk groupswas important
to include them as priority groups
in the recommendationsfor getting the influenza vaccine,
not only here in Argentina,
but also in other countrieswhich the pandemic not yet reached.
A year later,
when a vaccine against the pandemic H1N1 virus became available,
we wanted to see what had happened.
After a huge vaccination campaign
aimed at protecting at-risk groups,
these hospitals,
with 93 percentof the at-risk groups vaccinated,
had not a single patient
with the pandemic H1N1 virus.
(Applause)
In 2009:
251.
In 2010:
Zero.
Vaccination is an actof individual responsibility,
but it has a huge collective impact.
If I get vaccinated,not only am I protecting myself,
but I am also protecting others.
Sol had whooping cough.
Sol was very young,
and she hadn't yet received her first vaccine against whooping cough.
I still wonderwhat would have happened
if everyone around Sol
had been vaccinated.
(Applause)