Even on a train, deep under the earth, you can't escape them
True, the carriage seems almost empty but that's an illusion
because it's actually teeming with life
None of us is ever truly alone because we all carry microbes, a huge army of them
Every square centimetre of our skin holds at least two thousand bacteria,
bacteria that feed, breed and sometimes even travel
Although most of the time we are completely unaware of them there are,
in fact, hundreds of millions of alien life forms living in and on each one of us
We carry around more microbes than we have human cells
Think of them as very close family:
It's probably the most important relationship we'll ever have,
because whether they're in the air we breathe or the food we eat, microbes shape our lives
In this programme, we'll reveal the secrets of the microbes that live in and around us
The ways they spread,
and the speed with which they can take over
Microbes range from mutant bacteria that cause life-threatening disease...
to tiny viruses that can bring devastating plague
But the body has developed superhuman defences of its own
By following people as they get ill and get better,
we'll reveal how the body counter-attacks
Most startling of all are the medical pioneers
Who are now using the microbes themselves as weapons to treat diseases
Injecting patients with bacteria to treat asthma
And using viruses to destroy cancer
What we're now doing is turning killers into cures
lmagine a party of your best friends carrying your worst enemies:
Viruses
Viruses are a billion times smaller than us
which is why they can infiltrate a party without being seen
Viruses are really simple: Just tiny parcels of genetic material
But once inside us,
they multiply and destroy
Ones picked up easily include herpes,
transmitted by kissing, giving us cold sores
Or Hepatitis, which attacks the liver and makes you jaundiced
Flu viruses, transferred by sneeze or hand-shake,
cause spiking temperatures and hot flushes
Or viral meningitis, which can be rapidly fatal
Early symptoms include a blotchy rash
We are able to survive daily attacks by such lethal threats
Because our bodies have evolved a number of very effective ways of fighting back
We'll follow what happens to three-year old Alex
We started filming her soon after she became infected with the chicken-pox virus
And for a while, though infected, she looked and felt fine
But within days, the pustules started to appear,
as you can see in this series of time-lapse photographs
She's had a couple of days of the spots coming, and not being too bad, and then
Yesterday she was very quiet,
today she's basically not moved from the position
she's in now, so obviously the body's switching everything else off
I presume to fight off what it doesn't like
Alex caught chicken-pox from her older brother,
Josh, who recovered within a few days
But how will his sister get on?
Invading viruses, like the ones that cause chicken-pox, multiply incredibly fast
and they can pose a real threat to our health
Fortunately though our bodies have evolved
sophisticated defences against viruses
in fact nothing that modern medicine has yet
produced can match the human body's immune system
in the game of viral attack It's like a war game
The human body is a sprawling city;
the spiky ball, a virus
A virus that manages to elude our outer defences and get right inside the body
has just one objective: To make more copies of itself, to multiply
First, it has to find a suitable cell to infect...
Done.
Once inside, they're ready to take over
A virus uses the cell as a factory to make copies of itself
The cell bursts and dies, releasing more viruses into the body
Alex's pustules are packed with viruses, and more are erupting all the time
But Alex's body has also begun mobilising its own phenomenal defences
Millions of years of struggle between us and
microbes has created our sophisticated immune system
The most important defence against viruses are these Helper T-Cells:
They hunt out and identify harmful invaders
Once they've identified the enemy, they send a message to Killer T-Cells
These lock on and destroy
And we have other less obvious defences
She has bouts when she gets a bit hot if she's been to sleep
but she wakes up and she has a drink, and she cools herself down naturally
Alex's high temperature is actually a sign that her body is fighting back
Many viruses that infect us operate best at normal body temperature
So our bodies respond to invasion by turning up the heat
Although it makes Alex feel lousy
a raised temperature is helping rid her body of infection
But sometimes, even this is not enough
Alex's temperature becomes dangerously high and she's rushed to hospital
Attack by the chicken pox virus has
left her vulnerable to invasion by a different predator:
Bacteria
Bacteria are bigger, and much more complex than viruses,
and they can also be extremely dangerous
Alex's body has defences against bacteria:
Anti-bodies which travel in the blood,
and white cells that seek out and engulf their prey
Shall we check dolly's chest?
You check dolly's chest
Say: Cough, cough
OK, it's medicine time, honey
It's possible that Alex's natural defences could cope,
but her doctors aren't prepared to take the risk,
so she's given anti-biotics to fight the bacteria
Good girl, good girl,
Make you better
Come on, come on, daddy get you a lolly
You want to put- put the pain on you
and not especially when they're saying: Make it go away, Mummy, make it go away
You can't do anything for them, and that's the worst I think for any parent
it took a mixture of five different types of anti-biotics
to finally get her bacterial infection under control
A week after being rushed into hospital, Alex is home and feeling back to normal
Her immune system destroyed the chicken pox viruses,
and the anti-biotics cleared the bacterial infection
Anti-biotics are really wonderful drugs
But the problem with anti-biotics is that we have over-used them
They have saved many lives
But for how much longer will they go on being effective?
From the moment we began targetting bacteria with anti-biotics,
we were engaged in an arms race,
a race which, with the benefit of hindsight, only one side was ever going to win
At first, small doses of anti-biotics like penicillin worked miracles
They stopped harmful bacteria in their tracks
But very soon doctors began to notice that
they needed to give ever larger doses of anti-biotics just to have the same effect
And as we've gone on developing ever more sophisticated weapons,
they've gone on developing better defences
The problem is, bacteria don't stand still waiting to die: They evolve, very fast
They can do this because they reproduce at a phenomenal rate
a new generation every twenty minutes
So, no matter how big the hit, some bacteria will always survive
It's why they are the most successful organism on this planet; and when
bacteria become resistant to anti-biotics
the results can be terrifying
October 1999
and in London two trains heading in opposite
directions on the same line collided in a fiery explosion
As a result of the Paddington rail crash, 31 people died and over 400 were injured
Among them, was 52 year old Tim Streatfeild
He was burned almost beyond recognition
When they got him into hospital
they discovered that almost half his skin had been burned off
Our skin is our first line of defence against infection from microbes
Without this barrier, we're incredibly vulnerable
Tim was soon infected
and what was worse, the infection was VRE
or Vanco-Mycin Resistant Enterococcus
These superbugs are terrifying
because they've evolved resistance to all standard anti-biotics
But Tim's hospital had one experimental drug left to try: Linezerind
They gave it to him, and hoped
For four weeks, Tim was in a coma
He remembers nothing of the life - threatening drama played out in his body
You have a lot of nightmares when you're asleep for that time,
And a lot of the people you- who have been operating on you,
or have been helping you, appear in your nightmares,
so you have this strange feeling that you've actually have been awake for four weeks
but you've had other- other adventures than the ones you've had
The new anti-biotic saved his life
With the infection under control, Tim had to have numerous skin grafts
Slowly, the new skin started to grow
restoring his protective barrier against other infections
Slowly, Tim started to get his life back
OK, on you go with the hand again
Good man
Despite the anti-biotics
the infection is still not completely gone
You're inspired
Tim is kept in isolation to reduce the risk of the bacteria escaping, and infecting others
Now that I'm more mobile, it is getting somewhat frustrating,
I mean I feel like a caged lion, really, kind of-
with er feeling I want to go around, meet other people etc
So it's- it's- the benefits are- of being barrier-nursed are slipping away rather fast
Tim's burns still need daily attention
When you've finished, Mr. Streatfeild!
But his recovery is quite remarkable
Aren't I lucky I'm alive, basically
Best way of looking at it, and um not too disfigured but
I was never really a vision of beauty before anyway, so I'm quite happy
Tim's story shows us just how exposed we now
are to the threat from resistant bacteria
And that threat is getting greater and greater
Terrible diseases we thought we'd conquered are re-emerging
Diseases like tuberculosis, which destroy the lungs,
are coming back in ever more dangerous and resistant forms
Stopping their spread is vitally important,
and that sometimes requires extreme measures
On the Texas border, between the United States and Mexico,
a nightly struggle plays out between border guards and migrants from Latin America
Well we've got a group that's setting up close to the railroad tracks,
and looks like they're trying to discuss which way they're gonna go
They might have one of our units in sight
So from here it's anyone's guess what they're gonna do
What makes this game of Cat and mouse so deadly is that
the guards are trying to stop an invasion
An invasion by tuberculosis
TB which kills two million people a year is coming back
Many of those they catch are carrying the bug
Among those caught last night was Juan Lopez
He's just walked two thousand miles to try to find work
He lost everything when a hurricane destroyed his home in Honduras
I was hiding. There were two dogs
I had some sandwiches with me
The dogs smelled the sandwiches and they came to me and started to play
I stood up and the sheriff was passing and he arrested me
Everyone who's caught is routinely screened for infectious diseases
And since a third of the world is infected with TB,
there's a good chance that Juan has it
The role of the medical team here at the facility is to sreen
immigrants for diseases that might be contagious to the US population,
so we- we serve as defenders of the public health Here it is...
After a short wait, Juan meets Dr. Miranda
to hear the results of his X-ray
The news is bad
I want you to realise that you can see this side is normal, this side is abnormal
Can you see there's more whiteness on this side than on the other side?
This is the place where tuberculosis usually occurs
As a doctor I suspect that you do have tuberculosis
My suspicions are that it is quite serious
Juan's left lung has pockets of infection in it
If these are left untreated, they'll form chronic abscesses
He's immediately put into a special isolation room
TB is so infectious he's completely cut off from the outside world
Even the air in this room is filtered
And it's not just illegal immigrants like Juan who get locked up
US citizens who are found to carry TB, and who refuse to take their medicine,
can be forcibly held and treated
The US takes the threat of TB very seriously indeed
We will not be able to eradicate tuberculosis in this country
or industrialised countries as long as there's
a large reservoir of tuberculosis outside our borders
What we would like to do is be able to treat them and then
if they do qualify for entry to the United States
let them do that,
or if not at that point deport them, but deport them free of disease
Juan has a choice.
Either he can be immediately deported, or he can stay to be treated
He opts for treatment
My intention was to go home with something to give to my children
I don't have a house, I wasn't able to do that,
so I'll just go home to be with my children
Treatment takes up to six months
and at the end he still faces almost certain deportation
But Juan at least will be cured before he is sent home
Juan's story is a common one in the developing world,
but tuberculosis is now a growing threat in big cities like New York or London
But for all the damage it's done
TB has given us some real clues into the treatment for another plague,
a plague that threatens the developed world
On the night of June 24th 1994
a thunder-storm hit London
Soon afterwards, hospital emergency wards started to fill with desperately ill people
Over a thousand men women and children from across the city came in
complaining of a similar symptom - a sudden inability to breathe
Many were pale, sweating, on the point of passing out
Doctors were alarmed by what was happening and puzzled about its cause
Was it the beginning of some sort of outbreak?
A chemical spill?
Or even the early signs of a biological attack by a terrorist group?
In fact, it was none of these things
What all the people rushed into hospital were actually suffering from was asthma
The lightning storm had caused a huge cloud of pollen to be released
into the atmosphere over London
and pollen, although normally harmless,
in susceptible people can cause asthma in susceptible people
It was a striking example of how vulnerable
we're becoming to asthma and other allergic disorders
Decades ago, we appeared to have conquered infectious diseases like tuberculosis
And now we see this dramatic rise in allergies
Some doctors think the fall of one has led to the rise of the other
Bacteria are certainly not all bad
Some are essential for our health
The bacteria which grow on my skin, for example,
help protect me against other dangerous infections
But we're beginning to realise that the benefits may be more than skin deep
Bacteria may help prevent allergies
What happens in an asthma attack is that the body over-reacts:
It treats harmless things like pollen as though they were dangerous infections
The airways become inflamed and swollen, this narrowing makes it harder to breathe
Asthma can kill
Mark Dyer has been asthmatic since childhood
It doesn't stop him playing football, but the threat of an attack is always present
The only way I can describe it when you have an asthma attack
is you're being strangled while somebody's sat on your chest at the same time
You're trying to breathe in and nothing's actually happening
It's quite scary when it actually gets quite bad
But the trick is not to let it get that bad
I go everywhere with my Ventolin inhaler
sometimes if I forget it, it's always playing on your mind at some point you think:
Am I getting wheezy? Am I feeling a bit chesty? Although probably you're not
One explanation for the recent dramatic rise in allergic diseases
like asthma is known as the 'Hygiene Hypothesis'
Put simply, our body's white cells over-react
because they haven't got enough to do
I like to think of this 'Hygiene Hypothesis' as the lmmune system becoming mischievous,
much like a child becomes mischievous when it doesn't have anything to do,
and instead of reacting to things like bacteria
and viruses that are normally present in our environment
because we live in a healthy if not to say sterile- environment,
the immune system looks for other things to do,
and what it does then it starts to respond to things like allergens:
Pollens, house dust-mites
There's certainly plenty of evidence that children who
muck in and mix in with other children from an early age
are much less likely to develop allergies
Children who go to nurseries before the age of two are generally less allergic
And that's perhaps because they pick up lots of infections from other children
As adults, we obsessively avoid dirt
But these babies have no such inhibitions - everything and anything is worth a lick
An adult reaction is to take grimy toys away from children,
but perhaps these babies have got it instinctively right
Perhaps the odd bit of dirt helps lay down the foundations for a healthy future
Wild animals go further
Elephants acquire the microbes they need to stay healthy
by eating the dung of other elephants
It may not look appetising to us, but they instinctively do it
Now it's unlikely we're ever going to want to encourage our children to do this,
but amongst the microbes the elephants are hoovering up, there is,
surprisingly enough, something that's now being tested as a treatment for asthma
Micro-bacterium Vacchi, which is found in soil,
is a close relative of the microbe which causes tuberculosis
And strangely enough, they've discovered that getting infected
by it appears to help asthmatics
Like a seesaw
stimulating one side of the immune system
can suppress the other side
the side that causes allergies
Mark was keen to try it
There's two reasons really I'd like to take part in the trial:
The first reason is purely selfish:
To try and reduce the effect of asthma on myself,
and hopefully I can benefit from the trial;
and secondly is I'd like to do my bit for- for others, really
And so he became a guinea pig
and had himself injected with live microbes
It's a sort of vaccination
but a vaccination against asthma
So, is it working?
Well, the early signs are good
On average there is a 30% reduction
in the magnitude of the asthmatic response in the laboratory,
and I think this is encouraging
Well, since the injection it's- there has been a marked difference
I haven't had to use my Ventolin inhaler as much, if at all,
and my asthma seems to be very much more controlled
The idea of using microbes to treat asthma is still very controversial
We need to wait and see what happens
to people like Mark before getting too enthusiastic
But the approach, using disease to treat disease,
is definitely one that's gaining ground
And in Glasgow, they've taken this idea to its extreme
Twenty five year old Robert Swan has a brain tumour that
has affected his speech and paralysed his right side
He recently agreed to let doctors do something truly radical:
To drill a hole in his head and inject into it live viruses
I was twenty one at the time
I was an electrician for Scottish Power
I was loving life
I was getting on brilliantly...
This happened.
For a while they didn't know what was wrong
Then he was told he had an inoperable brain tumour called a Glyoma
I started getting headaches and
Just? 'cause somebody would say something to me
and about five minutes later I couldn't remember it
I think he knew he was dying
We used to speak about it
you know - wanted a party at his funeral
things like that, to write down something for him to be said...
There's things that you have to talk about,
you know- well, he wanted to talk about
Robert was given standard anti-cancer treatments,
but his brain tumour kept on growing
So, as a last resort, he agreed to have viruses injected directly into his brain
Robert knew he'd be a guinea pig
he was the first to try it
He knew there were risks
He knew it might not work
But by this point, he felt he had no choice.
With no further intervention, he was going to die
We'd been told it may not make any difference,
Then Robert wanted to do it
so you can't say no to him if he says he's quite determined
I was all right about that because it was either that or,
you know, just treatment all the time and...
The virus they chose to inject into Robert's brain was Herpes Simplex
The same virus that causes cold sores
It's particularly effective at destroying rapidly-dividing cells
I thought, well, could this virus destroy rapidly-dividing tumour cells?
And yet not affect cells which are no longer dividing?
And in the brain, for instance, most of the cells in the brain are no longer dividing
so that made us think: Well could this be used as a therapeutic tool
'cause we had turned something which was potentially bad
into something that was potentially good
Hoping against hope, they decided to go ahead
First they drilled a hole into Robert's head;
then they injected the virus straight into the tumour
This was really the first time in the world that something like this had been done
In a way, it's a relatively simple procedure,
but a fairly radical thing to be doing, sticking virus into somebody's brain,
so it was a whole new- new area
and quite an amazing thing to be doing
Against all the odds, Robert is still alive four years later
This is his brain scan
The tumour's still there
we've high-lighted it in red
It hasn't shrunk but it seems to have stopped growing,
and Robert continues to improve
He has check-ups with his consultant, Dr. Rampling
...I say it's getting better
lmproving steadily?
Aye
Well, this is your latest scan
Once again it shows that the tumour is very much static;
it's changed a little bit in consistency perhaps,
but it's difficult to tell because the types of scan are different
But certainly no worse
and no sign that the virus has escaped in any way and done any harm
No one really knows what will happen in the future,
but for the time being, Robert's life is returning to somewhere near normal,
and he's able to do things he loves most, like supporting Celtic Football Club
Makes me feel excellent
I've been OK ever since; I've had the dose
I shouldn't be alive, I should be lying... lying...
So it seems we can manipulate viruses
and use them to treat such diseases as cancer
But how can we use our increasing knowledge of viruses
to tame the most dangerous virus of all?
HIV, the virus that causes AIDS, is such a threat because
it can not only hide from our normal defences
but it also disables them
It gets inside the cells that are supposed to destroy it
and instead, destroys them
At least 33 million people are now infected with HIV
and most will die
In the next five years, this number is expected to triple
to over 100 million
Niambani Orphanage, on the outskirts of Nairobi in Kenya,
is home to seventy children with HIV and AIDS
They come here to die
Since the first officially recorded death from AIDS in 1959,
the disease has killed around 15 million people,
and 90% of them have come from sub-Saharan Africa,
and over one quarter of them are children
As well as the mounting death toll, AIDS is leaving a legion of orphans,
most of whom are also infected with the virus
In Kenya alone, it's been estimated that there around 350,000 infected orphans
Children like these have no real future
unless a cure is found or
more likely, we find better ways of slowing the progress of the virus
The battle being fought inside the bodies of
these children is a battle they are losing
The viruses, having invaded and destroyed most of the body's
natural defences, multiply unchecked
In the slum areas of Nairobi, one in four people are HIV-Positive
But what is encouraging is amongst the people who live here,
are a few rare individuals who seem to have a natural resistance to AIDS
Salome is one of those rarities
She is also a prostitute and on average has sex with six men a day
I live in Majengo. The way I see my life here is good, but not that good,
because I really don't like the way I live
I just don't like the work I do
Astonishingly
Salome doesn't have HIV, despite being repeatedly exposed to the virus
Her immune system is different to ours
It's able to detect HIV wherever it's hiding,
and so can mount a far stronger counter-attack
And this ability seems to be inherited
Salome's daughter, Mastidia, is also a prostitute and she is also not infected
Both women are taking part in a study to try to develop an AIDS vaccine
You haven't got a problem, but this doesn't mean you shouldn't be careful
Dr. Kimani, I'm being careful
but it could be bad luck if I get HIV through medication
I'm taking, or through the water
These women who are resistant to HIV
most of them are illiterate they are not educated
and it's been a big problem to convince them they're actually not HIV-positive
because they've actually seen their friends dying
and they know they've been doing the same sort of business
Dr. Kimani has so far identified 130 women who,
like Salome, seem to have natural immunity
Salome, and the other prostitutes like her, are unlikely superhumans
Yet they clearly have special powers
The quest now is to find out exactly what it is that makes them different
and to see if this natural resistance can be replicated by a vaccine
Blood was taken from my body, possibly to be told that I have no virus,
but if this vaccine could eventually come, it could help
I've got something special that I would like my friends to have
so they can be cured and we can carry on with our lives
It's a very very exciting finding, and I'm happy to be involved in it
Because this group has been accused of spreading HIV in our cities
and if it could be the same- same group that can offer some solutions, well and good
The blood samples have been sent to Oxford,
where the drive to develop a vaccine is well under way
So far, from the women's blood,
they've managed to extract specialised white cells
that appear to give them high levels of protection against AIDS
And they've made an experimental vaccine to boost
the production of these white cells in normal people
But can natural immunity be copied in this way?
Shouldn't be too bad
I'll let you know
OK, ready?
Local MP, Evan Harris
is one of twenty men who's volunteered to test the new vaccine
The vaccine is the only hope for future generations
in some of these African countries, who will never be able to afford the therapy
and the infrastructure, to treat HIV
we have to be preventive
No one yet knows just how effective this new vaccine,
based on the prostitutes' blood, will be
The scientists developing it are cautiously optimistic
And if the trials in Oxford are successful,
then the next stage will be to test it in Nairobi
Prostitutes will continue to be intensively studied
because once we've properly understood natural immunity
why some people fight off infections when others don't
then we'll be in a much better position to protect ourselves,
not only from AIDS but also from other future plagues
The war we've been fighting with microbes for millions of years
is not over, nor will it ever be
As quickly as we find solutions to old problems
new diseases will undoubtedly emerge
But by learning more about them and about ourselves,
we should ensure that we do, at the very least, manage to stay ahead