Comprehensive Guide to HPV Virus and Vaccines Explained

hello thank you for joining me my name is anil taylor i'm a consultant gynecologist and i practice in the uk

in this video i want to talk about the human papilloma virus the hpv virus and say a little bit about

vaccines the hpv vaccine so i have created some other videos

especially on cervical cancer and pre-cancer please search them out because they will help you to

understand what i say in this video as well so the ones that are most relevant are

the ones where i'm discussing why women should be having regular cervical smears

and another video on what abnormal smears mean

so please please have a look at them and so on the hpv virus front um so the hpv

virus it's it's what we call a dna virus it's a fairly bigish virus um and so it has an envelope

which uh is uh created uh by the the the virus um

and consists of consists of uh proteins called the l proteins or the late proteins

and using those proteins it creates an envelope

and that's the virus particle within that envelope um is contain the dna and the dna

codes for genes and roughly speaking there are three types of genes that

it codes for so it codes for the e proteins uh which are the early proteins meaning once the the the virus

has infected a cell it's these early genes that uh start um doing the viruses uh work

um and and then towards the end the l proteins the late proteins come into

action so the early proteins uh help to replicate the dna in the infected cell um and the

um l proteins um help to create the the surface envelope now there is uh the e6 and e7 proteins

or genes that are especially important especially for the high risk hpv types um which i'll

mention in in the next few slides so they help to transform the infected cell into pre-cancerous cells

so we'll talk a little bit more about that in the next few slides so hpv there are many many different types and

subtypes of hpv um more than 150 times and they're each given a number and they're broadly categorized into two

types they're low risk type or the high risk type so the difference between the low risk type

and the high risk time is the fact that the low risk type

are ones that don't really have a significant potential to transform the cells

into cancerous cells so they may cause mild pre-cancer but rarely if ever will

progress all the way up to to cancer the high risk types of hpv on the other hand do have that potential to go

all the way through the pre-cancer range and then into the cancer range so

it's the high-risk hpv that we are most interested in picking up uh and treating um so the uh

examples of the high risk type there the 16 and 18 are the most common types and um

they account for about 70 of all cervical cancers now um

what this chart shows is that of course there are other types that are also important in the

in in in causing cervical cancers

uh so they are the the the types 31 45 33 52 58. once again we'll come back to these

subtypes when we are talking about the vaccine but these seven types account for approximately 90 percent of

all cervical cancers now how common is hpv amongst women so when we are talking about both

low-risk and high-risk hpv types what this chart shows is that roughly about 60 percent of women at the age of about

20 will have been exposed to some form of hpv virus

and yes over the years the the immune system will clear it but by the age of 45 there will still be about 10 to 15

percent of women who will still have some form of hpv either low risk or high risk type

so it is a very common virus and and so what symptoms does it cause

and the answer to that is no hpv infection does not cause any significant symptoms meaning it does not

cause any discharge or any pain or any bleeding it is more or less a silent infection

and so when you are infected with that hpv virus

most women say 90 of women will clear the infection within the next one or two years

and the ones that don't um it's it's again that e6 e7 protein the

ones that help to transform the cells into pre-cancerous cells so they come into

play and that's why they're important um and once again we'll we'll say a little bit more

when we talk about vaccines so um cervical precancers or the thing that hpv causes uh

can can be either low grade or high grade so the low grade is a borderline or a mild abnormality uh

and certainly the low risk type can cause these abnormalities and rarely progress to the high grade

phase it's the high risk hpv that can progress from low grade to high grade and even

beyond into cancer if nothing is done um and so the hpv is detected

on the smear itself so the smear that women have um the cells that are collected uh they are deposited in in a

fluid and the the fluid is examined uh by the lab and they are able to detect the hpv

virus and they are able to type it so what that means is that the lab is mostly interested in the high risk type

if they find the low risk hpv they will consider the smear as being normal even if there is hpv if it is a

low risk hpv the smear will be called normal so it will only be called abnormal smear

or a positive smear if there is high risk hpv detected

and one of the questions that women ask when they are referred with an abnormal

smear is if they have gotten hpv should their partner

receive treatment to clear the hpv now the answer to that is

broadly no yes

hpv in men can cause cancers cancers such as penile cancers or oropharyngeal cancers meaning mouth

cancers throat cancers but on the whole the

penile cancers are quite rare much rarer than cervical cancers roughly

about four to five times rarer than cervical cancers so it's not necessarily a big problem in

men um if if we now move on to the vaccines um vaccines we can

talk about broadly speaking two types so the commonest type which is what everybody

knows about is the vaccine that prevents uh infection with hpv that's

what came out about 10 15 years ago and that's the one that uh young girls from the age of 9 9 are

vaccinated against so we'll look at the data to see how effective it is in the next few slides

the other type of vaccine which is um not known about

because it is very much experimental but it certainly does show a lot of promise

and that is the type of vaccine that is hopefully going to help us

try and clear persistent hpv infection diseases related to persistent

hpv so things like cervical pre-cancer vulval pre-cancer vaginal pre-cancer or anal pre-cancer amongst others

and so the way these two vaccines can be differentiated is so the first type the ones that we

are already using are the ones that immunize against the surface protein if you remember uh we

talked about the l proteins which make up the the surface envelope uh and and that

uh that protein is the one that the current vaccines uh immunize against

so the ones that are still in the experimental phase

the vaccines are the ones that are going to target the e6 and e7 proteins if you remember

these are the proteins that help to transform the infected cell into uh into a pre-cancerous cell so

this is very much experimental and trials are still in progress and hopefully

in in the in the next few years we will we will see these types of vaccines coming

into existence so when the vaccines first came out uh about 10-15 years ago um uh there were

the the the two types of cervax and the gardasil the cervax uh vaccinated against type 16 and 18. if you remember

those are the ones the high-risk hpv that uh cause about 70 percent of cervical cancer so it only protected

against the the the hpv that caused cancers gardasil

when that vaccine came out are roughly at the same time in addition to 16 and 18 it also

included protection against types 6 and 11. now roughly speaking 6 and 11 are low risk types but but they cause the

majority of genital warts so the rationale behind including those two was to try and uh minimize the the the

problem created by genital warts and again we will look at some of the data now more recently gardasil have now

brought out the gardasil 9 which now includes in addition to the 4 before

now it includes the 31 33 45 52 and 58 now if you remember earlier in my earlier slide i showed that those uh

seven high risk types account for about 90 of cervical cancer so the goddessel 9 is

now hoping to cover most of those viruses so who gets the

hpv vaccine now the initial studies were done on uh

individuals uh beyond about beyond the age of nine up to the age of

26 so it can safely be used in in that category and at the moment uh they

certainly are used to vaccinate women or girls uh after the age of nine

usually that happens at the school so those are the individuals who uh are

receiving the the the large proportion of vaccines um how effective is this hpv vaccine so

when the the vaccine was introduced about 10 15 years ago the data that it was based on was fairly convincing so

here um you can see that when comparing women who had the placebo vaccine

compared to the real vaccine and and looking at a roughly about 8 000 women in each group

the the high-grade pre-cancers all cancers they they were prevented or went down from 53

down to zero which is very impressive and with gardasil um who included the

protection against uh the the genital warts once again it was fairly impressive uh protection so it

went down from 91 out of roughly 8 000 to 1

in roughly 8 000. so that is very very good protection against genital warts and

indeed high grade pre-cancer and cancer so that was what was so convincing about

the vaccine and why it is now very much in

use so the question can be asked if if the vaccine is so

effective should these women still continue to have regular smears

and so and the answer to that is very much a big big yes these women should continue having

regular smears at least that is the current advice there is some data uh coming aloud coming out that is seeming

to suggest that these women who have previously been vaccinated may require fewer

smears in their lifetime but they still need to continue for the time being having their smears either three early

or five years now if somebody has previously been infected

with hpv or has actually had an abnormal smear with abnormal pre-cancer cells can they have this hpv vaccine and the

answer to that is yes they can have this vaccine and that is because most women who have previously been

infected or had pre-cancer cells will not have been infected against all those hpv's

types that the vaccines protect against so therefore these women can if they wanted to they

can have the hpv vaccine and that is all i want to say on this

subject uh thank you very much for listening um i have many other videos that i have uploaded um

on a similar topic um please search them out and

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thank you very much and until next time please stay safe