WHO’s Science in 5 on COVID-19 : Delta variant and vaccines

Does the current batch of approved vaccines protect us from the Delta variant? What is the level of protection? If you can still get infected even after being fully vaccinated, then why should we vaccinate? WHO’s Chief Scientist Dr. Soumya Swaminathan explains in Science in 5.

Vismita Gupta-Smith:
Hello, and welcome to Science in 5.

I'm Vismita Gupta-Smith.

We are talking today
about the Delta variant and vaccines.

Dr. Soumya Swaminathan,
WHO's Chief Scientist is our expert today.

Welcome, Soumya.

Our first question to you, Soumya,

is we know that the Delta variant
is more transmissible.

Please explain to us
what kind of protection

we get from the current batch
of approved vaccines.

Soumya Swaminathan: So we're
talking here about the Delta variant,

which is the fourth variant of concern

described by WHO

because it's both more transmissible
than the previous variant

and also has been able to resist
the antibodies that we have in our blood.

So what that means is that you need
a higher level of antibodies

to overcome this variant

as compared to, let's say,
the Alpha variant.

Now, the good news is that all of the WHO
emergency use listed vaccines

do protect against
developing severe disease,

hospitalization and death
due to the Delta variant.

So there are studies now

from countries where there is
a predominance of Delta variant

to show that people who've been vaccinated

are much less likely
to end up in hospital.

And you need the full
course of vaccination

in order to give you that full immunity
to protect you against the Delta variant.

So the important thing is

if you have access to a vaccine
that's approved by WHO,

please do take it and take the full course

so that you can be protected

both against the Delta
and other variants of COVID.

VGS: Soumya, explain to us, please,
the level of protection that you have

if you have received
one dose of the vaccine

versus if you're fully vaccinated.

SS: So the main goal of these vaccines
is really to prevent severe disease

because what we want is for people,
even if they get the infection,

is for them to recover from it
and not become seriously ill.

So that's something that all
of these vaccines do really well.

Of course, there are different levels.

You read about the efficacy trials.

They may range from 70% to 90%.

But in terms of just looking at
the prevention of severe disease

and hospitalization,

they're all very good, over 90% effective.

Again, they vary in the protection
against getting an infection.

Ideally, you know, you'd like a vaccine

which completely prevents you
from getting infected,

therefore you can't get ill.

But none of the vaccines
that we have currently

are 100% protective.

So this is why even if you're vaccinated,
you can get the infection,

but the chances are
you'll get very mild symptoms

or no symptoms at all,

and that the chances
of getting seriously ill

are really, really low.

VGS: So Soumya,
if we can still get infected

and also infect others
even after we are fully vaccinated,

then why get vaccinated?

SS: There are two very good reasons
to get vaccinated.

The first is to protect yourself
from getting severely ill

if you catch the infection.

We know that there's a certain proportion
of people of all age groups

who do get severely ill

and, you know, you could have a chance
of dying from this disease,

and this is what we want to protect.

So that's why you want
to get vaccinated in the first place.

But secondly, if you get vaccinated
and yes, you may still get the infection

because we know that these vaccines
are not going to protect you a 100%

from the infection.

So there is a small risk you get infected,

and you could pass it on to others.

Why do you want to take
the risk of doing that?

Why do you want to be one person
in the chain of transmission?

What we need to do in the world today
is to break those chains of transmission,

get control of this disease.

So that's why we say

get vaccinated as soon as you can get
access to your vaccine

when your turn comes,

and continue to take all the precautions

so that you are completely
protecting yourself

as well as protecting others around you.

VGS: Thank you, Soumya.

That was Science in 5 today.

Until next time then.

Stay safe. Stay healthy,
and stick with science.

Subtitles by Maurício Kakuei Tanaka
Review by Carol Wang