Hi there, I'm Mrs. Kemp, and welcome to today's lesson all about evaluating the global use of vaccination.

This fits into our unit, Defences Against Pathogens, The Human Immune System and Vaccination.

So there's gonna be lots of new information today, but please don't worry, I will talk us through all of it.

So let's get started then.

Our main outcome for today is I can evaluate the benefits and risks of vaccinations and explain the role of herd immunity plays in reducing the spread of disease.

These are some of the key terms that we're gonna be using today.

And if you would like to pause a video and read those over, please do that now.

But rest assured, I will talk through each one of those as we move through the slide deck.

So we've got three learning cycles today, and they are vaccination and smallpox, benefits and risks of vaccination, and finally, herd immunity.

Of course, we'll be starting with vaccination and smallpox.

So have you ever heard of Edward Jenner and smallpox? You may have actually heard of this in history before.

Have a little think.

Okay, so smallpox is actually a really serious viral disease.

You can see a little image there that's been taken under an electron microscope.

So symptoms included a rash all over the body and actually it had a mortality rate of around 30%.

So you were at risk of dying.

It was a very, very serious disease.

Even if people survived, they were often left with scarring, joint pain, and sometimes blindness.

And that scarring was very, very serious indeed, and it would've really affected somebody's life.

However, there was an English doctor named Edward Jenner, and he heard that actually milkmaids in his area didn't seem to contract smallpox.

A milkmaid is just somebody who milks a cow, essentially.

And he thought to himself, "Is there something else going on here? I wonder if this is something that we could help the entire population with." And he realised that actually these milkmaids seem to contract another disease known as cowpox, very, very similar to smallpox, but actually less serious.

And actually, he thought, "Maybe this is the link.

Maybe this is the thing that is stopping people from getting smallpox." So what he did is he actually took that theory and he tested it on an 8-year-old boy.

This would absolutely not be recommended in modern day medicines, okay? You wouldn't be allowed to just find a child and test them.

And what he did was he actually gave that pathogen, that cowpox pathogen that's very, very similar to the smallpox one, he gave that to an 8-year-old boy.

The boy developed a mild infection of cowpox, as we would expect, but he soon became well again.

What he then did, and actually there's lots of ethical reasons why you shouldn't do this, he then took the smallpox pathogen and he actually infected the boy with that smallpox pathogen, and the boy remained healthy, okay? So he didn't contract that disease.

This is an example of the very first vaccination that we had.

Jenner had used the cowpox pathogen then as a type of vaccine against smallpox.

This is a complete revelation to the medical industry.

Okay, true or false? The first vaccine contained the smallpox pathogen.

Was that true or false? I'll give you a moment to think about it, but if you need more time, please pause the video.

Of course, that was false.

Can you give a justification for your answer then? The vaccine contained cow's milk or the vaccine contained a similar but less harmful pathogen, cowpox.

Again, I'll give you a moment to think about it, but if you need more time, please pause the video.

Of course, it was that the vaccine contained a similar but less harmful pathogen, that is cowpox.

Excellent.

Well done.

Okay, so modern day vaccines actually contain dead or inactive, so they're not able to replicate forms of the pathogen, okay? And what your body does is it has an immune response to the antigen on that dead or inactive form of the pathogen, okay? And as a result of that, you will produce some antibodies.

and then actually what's more important is you will produce those memory cells.

And the memory cells that are made for that pathogen will be able to give you long-term immunity.

So actually, when you then become exposed to the real pathogen, you can see there on the graph that we get a really, really quick and fast spike of those antibodies in our blood.

So we are able to get rid of that pathogen much faster than if we'd never been exposed to the antigen before, and therefore, we do not become ill or feel poorly.

Now, actually in 1967, the World Health Organisation, or WHO, set out to try to get rid of eradicate the smallpox disease completely across the whole globe, and they did that through a really, really successful vaccination programme.

And actually by 1980, the World Health Organisation announced that they had completely eradicated smallpox, which, obviously, for such a deadly disease and also one that if will leave such awful scarring and possible blindness, actually this was a real success.

Which these disease has been eradicated through a successful vaccination programme? A, athlete's foot, B, Ebola, or C, smallpox? I'll give you a moment to think about it, but if you need more time, please pause the video.

Did you realise it was C, smallpox? Excellent.

Well done.

Okay, onto our first task of the day, then please get your worksheets out and you can record your answer on there.

This one is task A.

Alex has been sent a letter from his doctor, suggesting that he gets the HPV vaccine this year.

Write some advice to Alex to reassure him that the positives of vaccination.

Include information about smallpox and how a vaccine works.

I'll give you a moment to think about it, but if you need more time, please pause the video.

Okay, did you put vaccines contain dead or inactive forms of a pathogen? They stimulate an immune response, which leads to memory cells being produced.

These provide long lasting immunity, so the individual is less likely to contract the disease caused by the pathogen.

Smallpox is an example of a disease that has been successfully eradicated due to a successful vaccination programme.

If you'd like to add any more to your answer, please do that now.

Okay, onto our second learning cycle of today then.

This one is benefits and risks of vaccinations.

So the use of vaccinations has a real substantial positive impact on public health by controlling the spread of communicable diseases.

So any disease that is communicable and can be passed from organism to organism, it's really helpful if you have a vaccine because it means that you do not need to treat that person, but actually they've already got long-term immunity to that disease and they never become ill.

But like most activities then, actually it's not completely risk-free.

And sometimes, vaccinations can also have other types of side effects.

Now, people tend to underestimate the risks of familiar things, such as travelling in a car, okay? Lots of times people have lots of accidents.

And actually, it's one of the main causes of death, that has a really high risk.

But we then overestimate the risks of unfamiliar things.

So because we maybe don't have vaccinations every day, there's new vaccinations that come out.

People can get very, very concerned about these even though the risks are actually very low.

Some of the risks of vaccinations then can be short-term side effects, such aching muscles or fever.

You may have had a vaccination before where your arm hurts in that location where they've actually administered that.

There are very rare long-term ill health symptoms then, which we will discuss later on.

But vaccines are always trialled before they are approved for use.

So they'll make sure that they have been, first of all, tested in a lab.

They then will have had some animal testings.

And then they will have had human testing.

So they would've gone through a really robust trial system.

They will then be approved when the evidence shows that actually the risk from catching the disease are actually outweighed, or outweigh, sorry, the risk from having the vaccination.

So the disease has got a much higher risk than actually the vaccination itself.

And also the benefits of having the vaccination, so preventing that disease from happening, will outweigh any risks from having the vaccination.

So it's a really careful balance that scientists will have to really, really make sure that they have trialled and gain lots of evidence about before that vaccination is allowed to be used.

Okay, which of these statements are true? A, vaccinations are risk-free, B, vaccinations are trialled before they are approved, C, vaccinations commonly cause long-term ill health, or D, vaccinations are only approved for use when evidence shows the benefits outweigh the risk.

I'll give you a moment to think about it, but if you need more time, please pause the video.

Okay, did you realise that B, vaccinations are trialled before they are approved, and also D, vaccinations are only approved for use when evidence shows the benefits outweigh the risks.

Excellent.

Well done.

Okay, let's have a think about a case study then.

In this case, we're using COVID-19.

So COVID-19 is a disease caused by a virus, and it began in an a region of China in 2019.

The first recorded case was on the 17th of the 11th, 2019.

Only a very short period after, so only a couple of months later, actually, there was a recorded case in Japan on the 16th of the first.

That we also had a case in Thailand on the 13th of the first.

And that managed to get all the way over to the U.

S.

by the 20th of the first.

So we can see that once that started to spread around the globe, it went really, really quickly.

And actually from that point, it spread all over the place.

We got our first case in York, and it really spread super fast, and that's because people are always flying around the globe for holidays and also work.

And so diseases can spread really quickly these days.

On the 2nd of December, so actually just over a year from that first case being recorded, the first COVID-19 vaccine was approved for use in the U.

K.

It's a little bit different to the normal types of vaccines, and actually instead of using a dead or an active form of the pathogen, it actually used a copy of a viral gene instead.

Our body cells then use that viral gene to actually make the viral antigen.

Okay, so just like when a virus infects your cells and uses its own machinery in order to build up a new virus.

Actually, we used that technology in the same way that actually our body cells then made the antigen.

We then had an immune response to that antigen.

After the immune response then, just like with a normal vaccine, you produce memory cells, and this gives us long-term immunity against that COVID vaccine.

But because it was a new type of vaccine, people were a bit more concerned about it than they would have been normally.

There are some side effects from COVID-19 vaccinations, but they're usually very, very mild and typically only last one to two days.

Some side effects that people have noted are things like headaches, fever or chills, muscle pain or joint pain, tiredness and fatigue, upset stomach or vomiting, some swollen lymph nodes.

These are not that different from what we would normally expect from a vaccination.

So these are quite typical symptoms that people experience after vaccines.

There is in fact also a very, very low risk of some more severe side effects, just like there often are with lots of other types of vaccinations, but they are very rare.

These can include an allergic reaction, heart problems. However, evidence shows that the heart problems occur approximately one in every 10,000 people who have that COVID-19 vaccination.

It's a very, very small number.

Whereas actually COVID-19 is a really severe illness, where we saw lots and lots of people being taken into hospital, that is still currently happening, and people being put on ventilators, and people unfortunately dying from that disease.

The benefits of the COVID-19 vaccination then, they include a decrease in the time it takes to recover from the COVID-19.

So actually if you do get infected, then people do tend to recover a lot faster.

It also prevents serious illness and people being hospitalised and also people dying due to COVID-19.

It prevents the spread of the pathogen, which helps to keep it away from vulnerable people.

Vulnerable people would be you are very old and also people that maybe have a weakened immune system.

It reduces the need for social distancing and lockdowns.

And so life is able to remain normal.

For anyone that remembers being in a lockdown, it's where we weren't allowed to leave the house apart from maybe an hour a day to get some exercise, and you weren't allowed to mix with other households even if they were close members of your family.

So it really was quite distressing at the time.

It's estimated that in the first 10 months of use, the COVID-19 vaccination prevented up to 128,000 deaths and 262,000 hospitalizations.

So that is absolutely massive.

And so you can see that the benefit of having that vaccination really outweighs your risk of actually getting something more severe from that vaccination.

Okay, true or false? Heart problems are common side effects of a COVID-19 vaccination.

Is that true or false? Justify your answer.

Heart problems only occur in 1 in 10,000 people, or B, heart problems are just as common as other side effects of the vaccination, such as headaches and muscle pain.

I'll give you a moment to think about it, but if you need more time, please pause the video.

Okay, did you get false? And of course, that is because heart problems only occur in 1 in 10,000 people.

So it's very, very uncommon.

Okay, onto task B then, and please get your worksheet out because you can record your answers on there.

Make a table to show the risks of COVID-19 vaccination and how common each risk is.

There's a table there for you to record your results.

Make a list of benefits of COVID-19 vaccination, include benefits to individual people and to society.

Number three, explain whether you think the evidence shows the benefits of the COVID-19 vaccination outweigh the risks.

I'll give you a moment to think about it, but if you need more time, please pause the video.

Okay, let's have a look at what we could have had in our table then.

So side effects including fever, headache, and joint pain.

You could have an allergic reaction.

And there is a possibility of heart problems. Now, those side effects such as fever, headache, and joint pain, they usually only last about one to two days and they usually quite mild.

The risk though is quite common.

That allergic reaction can be severe, but it is very rare.

The heart problems are severe, but they are very rare.

And in fact, you may have put 1 in 10,000 people.

Some of the benefits then.

They decrease the recovery time.

They help to prevent serious illness, hospitalisation, and death.

Prevent the spread of the pathogen and keeps it away from vulnerable people.

Reduces the need for social distancing and lockdown so life can remain normal.

Do we think then that those benefits outweigh the risks? What did you decide? Evidence includes that the side effects are usually mild and short-lived.

Severe side effects are very rare.

There are benefits to individual people's health and to society.

So as long as you've backed your answer up with the reason why, then that will be an acceptable answer.

Okay, onto our final learning cycle of today.

This is herd immunity.

So vaccinating somebody gives them immunity against the pathogens, so it gives that person, that individual person an immunity.

But there are some people who actually are not able to get vaccinations.

This might include people who are allergic.

So we've mentioned before that actually allergic reactions can be a result of having a vaccine, but also people that have a weakened immune system.

Those could be people that are maybe living with conditions such as cancer and also HIV.

Vaccinating a large proportion of the population actually really helps to stop the spread of that pathogen, and therefore those people that are not able to get vaccinated are protected.

So if none of the population is vaccinated, a pathogen can spread easily through the population.

Those pinky purpley faces there, those are unvaccinated people.

We've got our infected person that's green, and actually, they would easily be able to spread that onto people that are in their close vicinity.

And then those people can then spread it to the people that are in their vicinity.

If only a small percentage of people get vaccinated, then, unfortunately, that pathogen can still spread quite easily.

So the people that are in blue, we've got extra people now, and they are the vaccinated people.

So our initial infected person is not able to spread it to them, but they are then able to, they're people that then pick it up from them that are not vaccinated, they can then spread it onto other people that are not vaccinated as well.

So we've got that disease still circulating easily within a population.

If most of the population are vaccinated, it actually helps to prevent the pathogen reaching those who cannot be vaccinated.

So we've still got one unvaccinated person here, that might be somebody that is maybe allergic to the vaccine or potentially has a weakened immune system.

This is called herd immunity.

And so the disease is then not able to be spread around that population, okay, because they are protecting that individual that's unvaccinated.

Okay, if most of the population have been vaccinated, those who cannot be vaccinated are protected by, A, antibodies, B, herd immunity, or C, memory cells.

I'll give you a moment to think about it, but if you need more time, please pause the video.

Okay, did you get herd immunity? Excellent.

Well done.

Okay, let's have a look at another case study then.

This one is measles.

Measles is a communicable disease, so it can be passed from organism to organism, and it's caused by a virus.

It usually occurs in early childhood and it can have really serious complications.

All right, the initial symptoms actually similar to a common cold, things like high temperature, sneezing and coughing, runny nose.

It then develops into a characteristic rash, the measles rash, which you can see in the image there.

If you take a glass and you push it onto the measles rash, it doesn't disappear.

And that's a really characteristic and should actually mean that you need to take that child directly to the doctor's or a NE really quickly.

So the measles viruses spread through droplets.

So if somebody sneezes or coughs, those droplets contain the virus and they disperse into the air, other people then breathe those in and become infected.

The best way to prevent the spread of measles is getting the MMR vaccine.

We usually get it when we are babies, and so you don't even know that you've had it.

This protect us against three different diseases, measles, mumps, and rubella, hence, MMR. Now you can see that once the vaccine for MMR was introduced, okay, there in 1988, the number of people contracting measles rapidly decreased very, very low levels, okay? So we can see that actually herd immunity is working there.

We've got lots of people vaccinated, and we've got really low numbers of those serious diseases.

Now, you need about 95% of the population to be vaccinated in order for herd immunity to work, and some people that cannot have the vaccination then because of those weakened immune systems or possible allergies.

However, sometimes there are people that actually choose not to have the vaccination, so they will have had a look for themselves at the benefits and risks of contracting the disease and having the vaccination, and they've chosen for themselves that they would prefer not to have that vaccination.

In 1998, a doctor named Andrew Wakefield actually published a paper against the MMR vaccination.

He linked it or suggested that by having the vaccination, it actually increased your child's risk of developing autism.

Now, we actually used a really, really small number of individuals for this study, and the study itself was fundamentally flawed.

So it wasn't accurate at all, an accurate representation of our population.

Unfortunately, the idea from his paper was picked up really, really quickly by newspapers, and it was publicised really rapidly, and the vaccination rates dropped really quickly.

You can see there, the pink line represents where that information came out, and we can see how quickly that the numbers of people getting the vaccination dropped.

Almost immediately after the paper was published then, other studies found no link between MMR vaccine and autism.

So actually, other scientists showed that there is no evidence, whatsoever, that links those two things together, but because it had been so widely published by newspapers and media outlets, that actually the damage was unfortunately already done, and people already had it in their mind and were too concerned to get their children vaccinated.

Not vaccinating children against measles has led to a loss of that herd immunity, and this has led to further outbreaks of that really deadly disease.

You can see across the graph there the spikes that have happened in the number of cases of measles in England since that paper was actually published.

Okay, which of the following are reasons that certain individuals may not be able to have a select few vaccinations? A, they may be allergic to the ingredients, B, they may be scared to have the vaccine, C, they may have a severely weakened immune system, or D, they may not be able to afford it.

I'll give you a moment to think about it, but if you need more time, please pause the video.

Okay, did you realise that they may be allergic to the ingredients, and also they may have a severely weakened immune system? Excellent.

Well done.

Okay, onto our final task of the day then.

Please get your worksheets out.

In 1998, Dr.

Wakefield published a paper on the MMR vaccination that suggested it increased a child's risk of developing autism.

It was quickly refuted, but the damage had already been done.

Explain why a drop in MMR vaccinations has led to outbreaks of measles.

I'll give you a moment to think about it, but if you need more time, please pause a video.

Okay, did you realise that the MMR vaccination protects children's against measles? Some people are not able to get vaccinated, such as those with a weakened immune system, while others choose not to.

In order to achieve herd immunity to measles, around 95% of the population needs to be vaccinated.

The claims of Dr.

Wakefield led to a drop in vaccination rates to a low of 80% across Europe.

This led to outbreaks of measles across the U.

K.

Okay, we're nearly at the end then, just going to go through those key learning points with you today.

Vaccines have had a positive effect on public health, including the eradication of smallpox and reducing the spread of many diseases.

Vaccination is not risk-free and may have side effects.

New vaccines are trialled and only approved for use when evidence shows that the benefits of the vaccination outweigh the risks.

Around 95% of the population need to be vaccinated in order to achieve herd immunity.

Herd immunity helps to protect vulnerable people who cannot have a vaccination.

It's been great learning with you today.

I hope you've picked up some new information.

Hopefully, see you again soon.

Bye!.