nm0239: yesterday i started by talking or i finished i should say [0.5] by 
talking to you about the different classification schemes that are available [0.
7] clinical classification schemes that are available for AIDS diagnosis [1.0] 
and for monitoring the progression in the disease [0.7] and you remember i said 
to you that there were two schemes there was one developed by the Centre for 
Disease Control in Atlanta [1.0] and then there was a second scheme developed 
by the Walter Reed Hospital in Washington [0.8] the atla-, the the C-D-C scheme 
[0.6] was [0.4] based primarily on clinical observation [0.2] so it was not 
terribly laboratory based [0.8] whereas the Walter Reed [0.4] scheme [0.3] was 
more based on measuring clinic-, you know measuring clinical parameters in the 
laboratory [0.7] over the years since these two schemes [0.6] came available [0.
4] it's the C-D-C scheme [0.3] that has gained [1.7] common usage [0.7] and you 
remember that it's divided into four stages [1.0] one through four [3.1] 
and that i [0.6] finished yesterday by talking about stage one which is the [0.
3] acute or primary infection stage [0.7] and i said to you that [0.5] during 
this period [1.3] that people were seroconverting they were they'd been 
infected [0.4] they were seroconverting the important thing to remember about 
this stage [0.5] is there is a large viremia [1.9] and so that at this stage 
the people [0.4] are probably [0.4] at greatest [0.7] er chance of passing on 
the infections to others [0.8] but in fact in the majority of cases [0.3] they 
will not themselves at that point know that they are actually infected [1.0] so 
the point at which they constitute the greatest risk to society in terms of 
passing on the infection [0.6] they are probably completely unaware that they 
are infected themselves [1.2] okay [0.9] stage one is of course followed by 
stage two [0.6] stage two is the [1.1] asymptomatic infection phase [1.1] so 
that's the phase along here [0.3] in terms of time [1.0] 
and whereas stage one [1.1] is measured in terms of [0.3] weeks [2.3] so really 
anything up to about [0.3] sixteen to twenty weeks that sort of period [2.1] 
stage two [0.6] is measured in years [2.2] and its [0.2] its length [0.3] is 
unpredictable [3.2] okay so [0.5] it's difficult to predict how long stage two 
is going to be for an individual [1.5] the key thing about stage two [0.4] is 
during stage two [0.3] although the people are infected [1.0] they are well [0.
2] they are ge-, in general terms [0.3] healthy [2.4] now clearly if you are 
someone that who is infected [0.7] the thing that you want to know more than 
anything else [0.5] is how long am i going to be in stage two [1.5] if you're 
going to be in stage two for thirty years [0.8] you're probably not going to 
worry too much about being infected [0.3] 'cause you're probably going to die 
of something else before you come down with AIDS [0.9] but if someone 
says to you [0.3] well you're likely to be in stage two for about two-and-a-
half years [0.6] given that you've almost certainly been infected in mid-adult 
life in the in the period [0.4] twenty to forty [0.7] then if somebody tells 
you that you're going to come down with AIDS in two-and-a-half years that's 
clearly [0.5] much more profound effect on your life [0.3] than if they'd said 
to you you were going to come down in a-, with AIDS in in thirty years [1.7] so 
[0.2] clearly one of the things that that [0.3] people have looked for [0.6] in 
[1.4] trying to study this infection [0.3] is prognostic indicators [0.3] of 
the length of period [0.7] of stage two [1.4] so are there any indicators are 
there any clinical indicators of the infection [0.4] that allow you to predict 
for an individual [0.4] how long they are likely to be in stage two [2.4] well 
what can we say about the length of [0.5] stage two i've said it's in years [4.
0] what do we know about the numbers [0.7] well [0.3] in the early days there 
was a [0.3] study done of [1.4] 
six-thousand-seven-hundred [0.9] homosexual and bisexual men in the United 
States [0.6] over a period of eighty-eight months [1.2] now that's about seven-
and-a-half years [1.3] these people were all infected [0.2] they were all [0.2] 
H-I-V positive [0.4] at the point when they were taken into the study [1.3] and 
in that seven-and-a-half years thirty-six per cent of them [0.9] had developed 
AIDS [2.7] forty-four per cent of them [0.6] had developed a condition called 
[0.5] ARC [1.2] ARC stands for AIDS related complex [14.6] and ARC is a series 
of opportunistic infections it's not full-blown AIDS [1.5] but it's [0.3] it's 
a [0.5] it's [0.4] what happens [0.4] at the end [0.2] of the asymptomatic 
period [0.4] when people are starting to go into AIDS [1.0] so forty-four per 
cent of them were [0.8] in ARC [0.7] twenty per cent of them were [0.3] 
asymptomatic so [0.2] twenty per cent of them after seven-and-a-half years [0.
4] were still [0.2] completely well c-, still in stage two [6.6] what about 
prognostic indicators [1.2] well [3.2] one of the [0.6] best prognostic 
indicators still [1.2] is the level of your C-D-four count [3.7] you will all 
remember i hope that [0.3] T-cells [0.4] in 
the blood can be divided into a number of [0.4] subsets depending upon the [0.
4] antigens being expressed on their outer surface [0.7] the two major 
divisions of [0.9] T-cells are into C-D-four-positive cells and C-D-eight- [1.
1] positive cells [0.5] the C-D-eight positive cells are the so-called [0.5] 
cytotoxic T-lymphocytes [0.7] so those are the affector cells [0.3] of the cell 
mediated immune response [0.8] whereas the C-D-four cells are predominantly the 
T-helper cells [1.3] and it's C-D-four cells [0.8] that H-I-V targets [0.4] 
predominantly C-D-four cells [0.8] that H-I-V will infect [0.3] that's not 
solely the case but that's the predominant population [0.4] of cells [0.3] that 
H-I-V infects [1.5] and what you can [0.3] show [0.5] is that [0.5] if you have 
a C-D-four count of less than two-hundred [1.9] per ml [6.0] then in a twenty 
month period in a study over 
a twenty month period with where people were entering the study [0.5] with less 
than two-hundred [0.8] C-D-four positive cells per ml [0.4] in their 
bloodstream sixty per cent of them [2.1] at the end of the [0.6] twenty month 
period [0.6] sixty per cent of them had AIDS [2.4] whereas for those with 
greater than two-hundred [1.3] C-D-four cells per ml [0.6] only ten per cent of 
them [3.6] were in AIDS [2.7] so you can see that is a fairly good prognostic 
indicator [1.5] if the if you measure the level of C-D-four cells in the 
bloodstream and you find that it's greater than two-hundred per ml [0.7] then 
[0.4] you have a [0.4] relatively [0.2] low chance of proceeding to AIDS [0.5] 
in the [0.2] next two-and-a-half years [0.3] twenty months [0.3] two-and-a-b [0.
3] er er under two years [0.4] next two years just under two years [1.2] 
whereas if your C-D-four count in the blood is less than two-hundred [0.9] then 
you have a significantly higher chance of progressing to AIDS in the next 
twenty-odd months [3.8] 
there is one slight complication in this measurement and that is that C-D-four 
cells undergo a [0.6] diurnal rhythm [0.2] that is to say they're there's a 
nm0239: if you measure them [0.4] at different times of the day you get 
different numbers [0.3] so you have to measure them at a specific time in the 
day because there's a natural biorhythm [1.6] of C-D-four level cells in the 
bloodstream [5.7] what about other indicators [1.2] of [1.6] progression out of 
asymptomatic phase into er [0.9] into AIDS [1.1] well [0.9] you can look at the 
[0.2] proliferative response [0.2] induced by [0.2] general antigens you will 
all have had [0.4] the Mantoux test [0.5] for T-B where [0.2] some antigens are 
spotted on your skin [0.3] and you you [0.3] come up in blebs [0.4] as a 
proliferative response to those antigens [0.5] whether you've got an immune 
response to those antigens [0.4] well you can take general antigens like that 
and you can test [0.7] people who are H-I-V positive [0.3] and ask how good is 
their response to such general antigens [0.5] if they give a poor response to 
general antigens [0.4] that's a bad sign [1.5] okay [1.1] if they 
have decr-, decreased natural killer cell activity [0.6] that's also a bad sign 
[4.6] other factors that seem to affect progression [0.4] out of the 
asymptomatic stage two [0.5] into the later stages [2.6] well [1.4] other 
infectious agents [1.3] there is some suggestion that [1.1] if you are infected 
for example with treponema [0.3] syphilis if you have syphilis remember [0.5] H-
I-V is predominantly a sexually transmitted disease globally as you'll see in a 
minute when i come on to the global figures [1.2] and [0.9] a coinfection [0.7] 
with [0.5] other [0.2] sexually transmitted diseases [0.3] seems to be bad news 
[6.5] there is a suggestion although it's never been quantified [0.3] that 
there may be a genetic component [0.9] to [1.1] susceptibility to [0.3] to [1.
0] progression into AIDS [1.2] now that's probably almost certainly got to do 
with the quality of your immune response how good is the immune response that 
you start out with [3.3] the better it is [1.3] the better your chance of 
remaining for a longer period [0.4] in the asymptomatic phase [3.0] when you 
come out of the asymptomatic phase into 
stage three [2.3] stage three is [4.5] sometimes associated with this AIDS 
related complex stage four [1.4] is full-blown AIDS [1.4] now in the last few 
years stage stages three and four [0.3] have tended to be conflated together [3.
7] because once people start to show ARC [0.5] they relatively rapidly progress 
into [0.9] into AIDS [4.3] now what are the symptoms of stage four [0.7] what 
sort of things do you [0.6] do you suffer from in stage four [1.4] well there's 
a variety of symptoms [1.3] chronic fevers [0.3] night sweats [0.3] diarrhoea 
[0.6] dramatic weight loss [1.4] herpes zoster shingles [1.4] oral thrush [1.8] 
er [1.4] athlete's foot [0.6] a whole series of opportunistic infections that 
normally your immune system [0.4] would deal with relatively straightforwardly 
[0.6] become major problems for you [0.9] quite often for example AIDS 
sufferers have athlete's foot that comes up to the knee [1.7] okay [0.5] it's a 
very unpleasant disease [1.1] once you get into full-blown AIDS [2.0] what is 
the [0.8] in order to [0.2] be categorized as in 
gra-, [0.2] in stage four [0.7] you have to have fevers for pers-, persisting 
for more than a month [3.6] involuntary weight loss at greater than ten per 
cent of baseline [1.3] so in other words if you weighed ten stone [0.6] you've 
got to have lost more than a stone in a short period of time if your natural [0.
2] body weight [0.4] is ten stone [0.3] and you've gone down below nine stone 
[0.4] then you're in then [0.2] you're in [0.3] full-blown AIDS by definition 
[0.7] you need to have had diarrhoea for more than a month [3.2] untreated [0.
5] now you should appreciate and i mean i'll come on to say something about 
this later on there are now of course [0.4] quite a lot of antiviral agents 
that are being used [0.6] at least in some parts of the world to treat [0.2] 
AIDS infection [1.0] but untreated [0.2] the median time from entering stage 
four to death [0.6] is about ten months [3.5] it doesn't differ [0.2] very much 
from one part of the world to the other it tends to be [0.3] slightly shorter 
[0.4] in the developing world and that's probably got simply to do with the [0.
2] fact that people are generally more 
malnourished [0.9] in the developing world so [0.3] in other words you know 
their general state of health [0.4] is poorer to start with [0.8] so once they 
go into AIDS they die quicker basically [0.6] than do people [0.2] in the 
developed world but we're only talking about a matter of [0.4] two or three 
months either way [0.5] it is a very unpleasant death [1.5] you know [0.8] i 
mean it's a lingering death [0.6] you're ill for several months you have 
massive weight loss [0.4] people end up [0.4] bleeding often from all the 
orifices of the body [0.4] they've got all these opportunistic infections it's 
a very unpleasant way to die there's no doubt about that [1.0] okay [1.5] all 
right let's [0.2] move on then from a description of the disease [0.4] to say 
something about the current situation globally [0.8] okay [0.5] now remember [0.
3] i've handed you out all these handouts [0.7] so the slides i'm about to show 
you don't need to copy down [0.7] but you do need to be aware [0.8] of [0.5] 
these figures [0.4] and how they're derived [0.3] once H-I-V once AIDS became 
clearly an important [0.3] progressive 
ecidem-, e-, [0.3] epidemic [1.3] the World Health Organization set up [0.7] a 
task force [0.4] to [0.5] measure the impact to measure the epidemic and its 
impact globally [0.5] and this task force now produces a [0.6] a global report 
[0.2] annually in December [0.9] and so what i'm going to show you [0.2] are 
the figures from December nineteen-ninety-seven [0.5] and in a month's or so's 
time [0.3] there will be figures coming out for December nineteen-ninety-eight 
[17.1] right this gives you an indication [0.7] of the W-H-O's estimate [0.5] 
of the number of adults and children [0.8] estimated to be living with H-I-V 
infection [0.8] at the end of nineteen-ninety-seven [2.0] let me stand here 
it's easier [0.9] now the first thing that you can see is the global figure at 
the bottom [0.6] thirty-point-six-million the W-H-O estimates thirty-point-six-
million people [1.1] globally living with H-I-V [0.9] at the end of nineteen-
ninety-seven what does that mean in terms of the global population [0.5] it 
means about one in 
ha-, one in one-hundred [0.4] adults [1.8] so one in a hundred adults round the 
world is H-I-V positive [2.1] now remember that the median time [0.4] between 
infection [0.9] and full-blown AIDS [1.4] is now established in developed 
countries such as North America to be about ten years [0.5] right around about 
ten years [1.8] in the developing countries [0.8] the median time between 
infection [0.5] and full-blown AIDS is about eight years [0.3] it's not that 
much [0.4] less [1.6] in untreated remember [2.2] you're going to die in about 
a year just under a year [1.5] so what do these figures mean these figures mean 
that in sub-Saharan Africa [0.4] we can expect [0.5] somewhere in the excess of 
twenty-one-million deaths [0.4] in the next ten years 
nm0239: okay [1.1] in Latin America [0.5] one-point-three in the Caribbean 
three-hundred-thousand in North America approximately a million [0.9] people [1.
2] northern Africa two-hundred-thousand Europe half-a-million [0.7] eastern 
Europe central Asia [0.2] two-hundred-thousand [0.8] eastern Pacific four-
hundred-and-twenty-thousand [1.0] south-east Asia six-million [0.6] Australasia 
relatively small numbers [0.3] you can see from these figures [0.5] that the 
area [0.6] of greatest importance in terms of the the epidemic is sub-Saharan 
Africa [0.6] something like two-thirds of the total number [0.4] of people 
infected [0.4] are in the countries referred to as sub-Saharan Africa [4.2] 
those are the f-, those are the figures for [1.0] adults and children [0.4] of 
those about a million [0.8] are children [0.2] under the age of fifteen years 
[0.3] and predominantly [0.8] those children have been infected at birth [1.8] 
the chance of [1.1] a pregnant woman passing on the infection to her child at 
birth [0.3] varies somewhat from country to country [0.5] but is roughly thirty 
per cent [4.9] and of course these children [0.2] are infected [1.0] and 
infectious [0.2] as a result [0.4] although in the asymptomatic period because 
of the low levels of virus [0.3] you're not very infectious [1.3] and they're 
going to die before their tenth birthday the majority of them [1.6] okay [0.3] 
you can see again that the the f-, [0.2] place where the figure is [0.8] 
largest [0.4] is sub-Saharan Africa [0.7] almost all of 
the million- [0.8] plus is in sub-Saharan Africa [4.3] what about the number of 
deaths [0.9] from the beginning of the epidemic [0.7] until the end of nineteen-
ninety-seven [1.0] so this is a cumulative total how many people have died [0.
4] of AIDS in the last [1.0] almost twenty years seventeen eighteen years [0.5] 
you can see that the cumulative total is now eleven-point-seven-million [2.8] 
of which [0.3] approximately nine-and-a-half-million this thing is really 
giving up the ghost [0.5] approximately nine-and-a-half-million again are in 
sub-Saharan Africa [1.1] four-hundred-and-twenty-thousand in North America [0.
6] two-hundred-thousand in western Europe [5.5] estimated deaths in children [0.
2] of those eleven-point-seven-million [0.4] it's estimated that two-point-
seven-million of those are children [0.2] under the age of fifteen [5.8] 
estimated deaths during nineteen-ninety-seven [2.3] two-point-three-million [0.
5] the number of deaths is accelerating of course as we get further into the 
epidemic [0.4] the total number of infected people [0.9] er 
is getting larger [2.2] and of course there are more people who have now been 
suffering from infection for a longer period of time [0.3] and so they are 
starting to die [0.8] in large numbers two-point-three-million of which one-
point-eight-million [0.7] died in sub-Saharan Africa [0.7] in the last year in 
the in the year of nineteen-ninety-seven [0.9] we're talking big numbers here 
[1.0] as you can see i mean [0.7] you will have seen if you've read the news [0.
3] that it's estimated that this is on a par with the number of people dying 
from malaria [0.4] each year [6.1] estimated that half-a-million children [0.5] 
died from last year from [0.2] H-I-V infection [7.7] this is an interesting 
figure [0.4] the estimate of the number of people who newly acquired [2.1] H-I-
V [0.5] during nineteen- [0.2] ninety-seven [1.2] let me get to that on my er 
[9.5] five-point-eight-million [1.6] that's about a hundred-and-sixty-thousand 
people a day [0.8] being infected [0.6] roughly [1.8] again the great bulk of 
them [0.4] in sub-Saharan Africa nearly four-point [0.4] nearly [0.2] 
well [0.2] just exactly four-million of the five-point-eight-million [0.5] 
being infected [0.3] in sub-Saharan Africa [1.1] number's much lower in North 
America and western Europe [1.7] in fact in North America [0.8] the infection 
rate is declining [6.0] number of children [2.1] you can see [1.2] nearly six-
hundred-thousand children [0.2] infected last year but look [0.2] how many of 
those six-hundred-thousand it's estimated were infected [0.6] in sub-Saharan 
Africa [7.9] what does this mean [0.7] what are the social consequences of some 
of these numbers [3.3] this is an estimate [0.5] of the number of children [0.
2] orphaned [0.7] by AIDS [3.0] during the epidemic [1.9] so it's estimated 
that something like eight-point-two-million children globally have been 
orphaned [0.4] by their parents dying of this disease [1.0] of which nearly 
eight-million are in sub-Saharan Africa [1.9] okay [1.1] i mean these are 
really these are numbers that clearly you only have to stop and give a little 
bit of [0.5] social thought to this to realize these are numbers that have 
profound [0.4] social consequences [1.0] you 
know [0.2] these countries are having to deal with [0.4] eight-million children 
[1.2] under the age of fourteen [0.2] who have no parents [1.0] okay [0.6] this 
is not a small orphan problem this is an enormous problem [1.3] and of course 
[0.6] these are the countries that are really with the exception of South 
Africa itself [0.3] are really very poverty-stricken countries [4.0] what can 
we say about the [0.5] regional statistics [1.0] okay [0.4] the W-H-O divides 
the world into a number of regions [0.4] i mean the interesting thing about 
this table [0.5] i'm not going to go through it in [0.6] great detail [0.4] but 
i want you to [0.4] focus your attention [1.4] on this column here [2.6] this 
is [0.2] adult prevalence rate [2.0] so this is the number of adults in your 
population who are infected [2.0] and if we take sub-Saharan Africa as a whole 
[1.1] it's seven-point-five seven-point-four per cent [2.9] now the 
consequences of that are [0.5] that [1.1] unless [0.7] there's some treatment 
that is come up with that is be able to be that is cheap enough to be used on a 
very large scale [1.6] in ten 
years' time [0.4] seven-and-a-half per cent of the adult population in sub-
Saharan African is going to be dead [1.6] okay [0.8] i mean again [0.3] you 
just have to stop and think about what the enormou-, [0.4] and this hides some 
[0.3] really even more horrific figures for example in Botswana [0.3] something 
like twenty-four per cent of the adult population [0.6] is H-I-V positive [1.6] 
think of the consequences for example of Coventry [0.4] of going into Coventry 
[0.6] and killing [0.5] in a ten year period [0.2] twenty-four per cent of the 
adult population of Coventry [0.5] how would the city of Coventry [0.3] survive 
as a social structure how would it run [1.1] you know it's not easy to see [0.
3] how these societies socially [0.3] are going to cope with the consequences 
[0.6] of this infection [0.5] yeah [0.9] these are very large numbers and 
nobody really knows actually [0.8] what are going to be the [0.2] the social 
consequences [0.4] you can see that they're bound to be profound [1.1] but in 
the end no one is sure exactly what they will be 
nm0239: this is a [0.3] a global view of infection [1.1] at the end of 
nineteen-ninety-seven and this is really just a way of [0.4] of showing you 
where the hot spots are basically [0.4] and of course it just reiterates that 
the hot spots are in sub-Saharan Africa [0.9] s-, [0.9] the cool spots [0.2] 
appear to be [0.6] places like [1.3] er Russia [0.9] north Africa [0.7] western 
Europe [0.2] Australasia [12.8] these diagrams are [0.6] are there to give you 
an idea of the spread of the disease over time [1.5] and you can see here is 
what it looked like in the [0.7] early nineteen-eighties in fact [0.4] the 
epicentre in Africa [0.4] in the early nineteen-eighties was [0.6] n-, [0.3] 
the northern region of sub-Saharan Africa [1.2] areas such as [0.3] Kenya [1.0] 
Uganda [2.4] but over the years what you can see is it pread-, spreading 
progressively out from that epicentre [0.3] and particularly spreading 
progressively south [1.0] and so now [0.5] the epicentre is down here countries 
like Namibia [0.6] Botswana [2.0] Zimbabwe [1.6] and look at the figures [0.9] 
estimated percentage of adults in the fifteen to forty-nine group [0.3] who are 
infected [0.5] between sixteen and thirty-two per cent [0.9] in these 
countries [5.0] here's a similar thing for [0.3] South America and the 
Caribbean area [1.0] you can see that the values are much lower [2.7] but 
they're still in some countries quite [0.4] profound i mean two to eight per 
cent of your population in Guyana for example [1.2] if you lose eight per cent 
of your adult population in a ten year period that's going to have pretty 
dramatic social consequences [3.9] this is [1.3] er [1.0] spread of H-I-V [0.7] 
throughout [0.4] south-east Asia [1.4] and the key thing to pick up here [0.5] 
is the very rapid spread [0.4] in the latter part of the nineties [0.8] in 
India [0.6] and the countries here [1.1] Thailand [1.0] miran-, Miranmar or 
what we used to know as Burma [1.1] Bangladesh [1.7] you can see the figures 
are between half a per cent and eight per cent [0.2] prevalence [2.1] i'll 
throw you out a statistic from [0.7] from last year's [0.6] er report and i i 
will put [0.3] copies of these reports [0.3] which can actually be downloaded 
from the W-H-O web site but i'll put copies in the library of the nineteen-
ninety- [0.6] seven [1.0] end of ninety-seven figures 
so that you can read through it it's about a [0.4] thirty or forty page report 
and it gives much more detail [0.4] than i am able to give in this lecture 
about the numbers in different parts of the world [1.1] but for example in 
India [2.3] the main route of spread [0.8] of [0.4] H-I-V in India is by 
heterosexual contact [3.6] in the area around Bombay [0.7] the W-H-O estimates 
that there are a hundred-thousand prostitutes [1.0] with an average a five [1.
1] clients a night [0.9] and greater than twenty per cent of them are H-, of 
the prostitutes that is are H-I-V positive [1.2] now if you just think about 
the implications of that in terms of a [0.8] explosive spread of disease [0.9] 
okay and you'll see in a minute something about [0.7] some some figures about 
the number of people using condoms in some of these areas that are undergoing 
explosive spread of the disease [3.8] this is this is a a table that's 
important to look at because this gives [1.9] some idea of [0.2] of the picture 
now what this is telling you [0.9] is the proportional increase [0.6] in [0.2] 
prevalence rates bet-, in the last three years [1.7] so this tells you where 
things are [0.6] spreading [0.5] where the disease is spreading most rapidly [2.
4] not surprisingly some of the s-, countries of sub-Saharan Africa come into 
it [0.9] but look at this [0.9] i mean this is a very worrying thing [0.6] in 
the former Soviet Union [0.4] they've seen a greater than hundred per cent 
increase [1.1] in prevalence rate [0.4] in the last three years [1.7] okay [5.
2] so i've already given you this figure [0.8] more tha-, about a hundred-and-
sixty-thousand [1.5] new infections a day [1.8] more than ninety per cent of 
the infections are in developing countries [1.2] the important point about that 
[0.6] is that whereas [0.2] as i'll come on to in later lectures [0.7] there 
are now [0.8] AIDS therapies available [0.7] A-Z-T various protease inhibitors 
[0.4] these are all expensive [0.6] and there's just no chance whatsoever in 
the foreseeable future [0.5] that these therapies are going to be used in these 
developing countries they simply cannot afford to do it [3.5] about sixteen-
hundred of this 
hundred-and-sixty-thousand are children under the age of fifteen that's per day 
we're talking about [1.7] fourteen-thousand [0.4] about [0.3] this is the 
important point that i haven't alluded to before because i've [0.6] talked when 
i was talking yesterday [0.4] about the initial phase of the [0.3] the epidemic 
in North America [0.5] where the high risk group [0.4] were [0.2] homosexual 
males [0.5] you remember i said to you that there was a profound change in 
their social behaviour [0.6] associated with [0.5] the o-, the spread of the 
epi-, epidemic [0.4] from one of [0.5] high promiscuity [0.2] I-E high risk [0.
5] to one of essentially monogamy they became married [0.2] more or less [0.8] 
and as a result [0.3] the infection rates in homosexual males [0.3] in North 
America dropped dramatically [1.5] but [0.5] it is a sexually transmitted 
disease globally [0.3] forty per cent of the people being infected are women [1.
2] fifty f-, per cent are in the fifteen to twenty-four age group [0.2] they're 
in your age category [1.7] okay globally [2.3] i should just say in passing in 
case case i forget to mention it again [0.6] for women who get infected [0.6] 
if 
you're infected with H-I-V [0.2] about the worst thing that can happen to you 
is to get pregnant [1.6] and the reason why that's a problem is because [0.3] 
one of the consequences of pregnancy [0.4] is a natural immunosuppression [2.2] 
so [0.3] as a result of becoming pregnant [0.3] a woman will naturally 
immunosuppress [0.5] that is a question of [0.6] preventing rejection of the 
foetus of course [0.6] now if you're suffering from an immunosuppressive 
disease [0.3] if you naturally immunosuppress yourself [0.6] that's bad news [0.
6] and a very common scenario [0.5] for [0.3] H-I-V infected women [0.2] who 
become pregnant [0.5] is the [0.4] the becoming pregnant [0.2] tips them over 
from being asymptomatic [0.4] into [0.2] suffering from AIDS [2.0] they're 
suffering from AIDS so at the time of delivery [0.3] there'll be a lot of virus 
around [0.5] high chance of infecting the child [1.0] or a common scenario is 
[1.3] the child is born [0.2] is infected [0.2] the mother dies within [0.3] a 
few months three or four months of birth [0.4] you're left with an infected 
baby that's orphaned [0.9] and is itself going to die [0.8] before the age of 
ten 
almost certainly [0.3] who's going to look after it [0.8] who's going to want 
to foster [0.5] an H-I-V infected child it's not [0.3] not a thing that's [0.4] 
you know these are [0.5] these are [0.3] er facts that have profound social 
consequences like i've [0.3] tried to emphasize over and over again [3.6] now 
this is just a reiteration of the tables i showed you before cumulative numbers 
[2.5] and also for children i'll pass over those relatively quickly [2.0] here 
are some figures for [0.6] southern Africa [0.9] looking at prevalence rates [0.
5] in different [0.3] states different provinces of southern Africa [1.1] and 
look at the tracking since the early nineteen-nineties since nineteen-ninety [0.
7] through to nineteen-ninety-seven [1.7] just look how fast [0.7] the epidemic 
is spreading [1.1] you've gone from [0.4] you know [0.2] about one per cent one 
or two per cent [0.3] in Kwazulu and Natal [0.7] in nineteen-ninety one to two 
per cent of adults being infected which itself is bad enough [0.7] to now [0.5] 
greater than twenty-five per cent [0.4] adults infected [0.4] 
in that small province [4.3] similar figures for the s-, Soviet Union [2.2] 
newly number of diagnosed infections [0.3] starting in nineteen-eighty-seven [0.
7] and running through to nineteen-ninety-seven [0.5] the key feature to look 
at is here look what's happened in the last two years [1.1] you've got an 
exponential [0.4] growth going up from [0.9] less than five-hundred [0.3] to 
fifteen-hundred [0.4] to four-and-a-half-thousand [3.9] [sniff] [2.5] this is 
transmission route [0.3] for the Soviet Union [1.4] what you can see is that 
the main route [1.3] of transmission in the Soviet Union at present [0.4] is 
intravenous drug abuse [2.1] the use of uncontaminated er the use excuse me of 
contaminated needles [0.9] following intravenous drug abuse that's the most [0.
5] prevalent cause of infection [6.1] one of the things that you see when 
social structures break down and you get sexually transmitted diseases [0.6] is 
it isn't only H-I-V that's a problem [0.6] here you see the figures for some of 
the former Soviet Union states Belarus [0.4] Moldova [0.2] fede-, [0.5] 
Russian Federation and Ukraine [0.2] for syphilis [0.8] from nineteen-seventy-
six to nineteen-ninety-seven [0.9] what you can see is nothing much is 
happening pretty low levels [0.7] to nineteen-ninety-one [0.8] and then up it 
starts to come [6.4] this is an interesting figure [2.0] for a number of 
countries of southern Africa [0.9] this is a life expectancy [1.9] calculated 
life expectancy value [0.6] now what you can see is that [0.5] from the 
nineteen-fifties [1.2] through to the middle eighteen middle nineteen-eighties 
[0.6] the life expectancy [0.7] in [0.6] Africa [0.2] was increasing [0.8] this 
is a mark of [0.6] man being able to combat infectious diseases [0.5] 
improvements in combating infectious diseases [0.4] and general malnourishment 
is resulting for example in Botswana [0.6] in an increase of in the average 
life expectancy from about forty-three [0.8] up to [0.4] over sixty [0.5] not 
too different from what the life expectancy was in dev-, is in developed 
countries [0.8] in the upper sixties i think it's sixty [0.6] sixty-seven for 
man and seventy-three for woman if i remember rightly [1.3] but you can see in 
the last [1.4] 
ten years [0.7] it's dropping back again [0.7] in all of these countries some 
more quickly than others [0.5] the ones it's dropping back in most quickly are 
the ones with the highest prevalence rate [0.7] for H-I-V infection [1.6] so [0.
6] you know not to put too fine a point on it this is almost like a biblical 
plague here in these countries i mean this isn't just [0.4] capping off [0.9] 
your life expectancy it's actually reducing life expectancy in the population 
as a whole [3.5] by contrast [1.2] in western Europe [1.0] what you can see is 
that [0.3] it looks like in western Europe [0.8] the [2.2] infection is [0.6] 
being got under control in the sense that the number of new AIDS cases [0.3] is 
now actually dropping [2.8] now that's a combination of [0.8] a reduction in 
infection rates [0.8] and also [0.4] the [0.2] increasingly widespread use [0.
3] of antiviral chemotherapy [0.4] holding people [0.6] in the asymptomatic 
phase [1.4] so it's not solely due to changes in the infection rate [5.4] well 
this is just another i mean you can i mean i won't go through this this is 
just impact of AIDS on under child fi-, under [0.2] under five child mortality 
rates in a number of African countries [0.7] that d-, [0.2] with and without 
AIDS you can see that of course [0.4] AIDS have a [0.3] AIDS has a dramatic 
effect [1.9] mother to child transmission [1.3] you can see [1.0] er [0.3] how 
it's rapidly gone up transmission [0.9] by [1.9] er mother to child 
transmission direct transmission of H-I-V or transmission through [0.3] 
breastfeeding they both go up you can trans-, [0.4] transmit H-I-V by 
breastfeeding [6.0] well this is just another way of depicting the graph i 
showed you earlier this is [0.3] increased mortality rates [0.2] among men in 
the fifteen to sixty age group [1.0] based on whether or not whether or not [0.
8] there is [1.0] er [0.7] high levels of H-I-V [4.0] proportion of [1.2] adult 
mortality [0.5] attributable to H-I-V [0.8] well you can see that in a small 
Ugandan town [1.2] it's about [1.1] two-thirds to three-quarters of it [1.4] so 
this has become a really major killer [7.2] well [0.7] you can take from this 
what you will i'm not 
going to go through all of these in great detail [1.2] this is an interesting 
one that i alluded to earlier [2.2] the percentage of sexually active men using 
condoms [0.7] by age and group and type of partner [0.8] in nineteen-ninety-six 
for [1.1] couple of countries where there is a big H-I-V problem despite the 
fact [0.9] that they've got a big H-I-V problem and it's due to heterosexual 
spread [0.4] look how [0.4] you know in Malawi [2.1] where there'll be fifteen 
to twenty per cent of the adult population is infected so your chance [0.5] 
with unprotected sex of being infected is very high [0.4] nevertheless still 
only [0.4] twenty-odd per cent of males [0.5] are using condoms [1.8] and just 
to show you that i'm not sexist [1.1] okay [0.3] this shows you the figures for 
women [1.7] okay [0.8] same thing i mean very low levels of women [0.2] using 
condoms [2.3] and what's the [3.2] er [2.8] i alluded earlier to the fact that 
if you're H-I-V positive as a woman [0.7] about the worst thing that can happen 
to you [0.5] is that you get pregnant [1.5] look at the pregnancy rates [0.8] 
for by 
the age of nineteen in a selection of these countries that are most highly 
affected [1.5] okay [0.6] i mean [1.4] in virtually all case well in all cases 
including Senegal it's greater than forty per cent [2.6] so that would mean [0.
5] that you know forty per cent of you in this room if you were in these 
countries forty per cent of the women that is would have already had a child by 
now [1.0] okay [1.1] and of course with high prevalence rates of H-I-V 
infection [0.8] this is a real problem [2.4] okay we'll we'll pass over that [0.
2] and come back to that later [4.9] what i've tried to give you then in those 
handouts and in the slides i've gone through [0.6] is a picture [1.0] globally 
of the disease as at the end of nineteen-ninety-seven [1.4] the numbers are 
very large of course [0.7] yeah [1.1] and [0.3] the disease is having profound 
social consequences around the world [1.3] the reason i've laboured in going 
through this is because as i said to you [0.3] when you go out of here with a 
degree in microbiology and virology [0.3] and you 
tell somebody you know something about viruses [0.6] almost certainly the virus 
that they will ask you about is H-I-V [0.7] and they will expect you to be 
reasonably informed and what they won't want to know from you [0.3] is how tat 
and rev works [0.6] okay what they'll want to know from you is [0.7] what's the 
sort of number of people who are suffering from this [0.7] where is it the 
biggest problem [1.4] what are your chances of being infected [0.5] okay [0.6] 
now on the end of the handout i've [0.3] tacked out given out to you [0.4] i've 
tacked on [0.4] the last two monthly reports [0.4] from the Public Health 
Laboratory Service [0.4] of the situation in the United Kingdom [1.6] and [0.4] 
the best one [1.2] to look at [1.7] is actually the one from the end of August 
because that gives you some breakdown [0.9] by region [1.2] as to [0.2] the 
numbers involved [4.1] and the important point [0.9] i can't i can't find the 
table i'm looking for in the [0.2] sheets i brought with me [0.5] yeah oh yeah 
it's it's this table here it's actually in the September one 
not i think it's the very last page [1.4] of the handout i gave you [3.1] what 
you can see [0.3] is that [0.8] there's something like thirty-thousand [0.3] 
well just over thirty-thousand [0.5] H-I-V positive people [1.5] in Britain [0.
7] somewhere over three-and-a-half-thousand of them have died of AIDS so far [0.
7] it's not a uniform distribution [0.6] across the country [1.4] er [1.1] the 
West Midlands there are about a thousand people thousand H-I-V positive people 
in the West Midlands which compares to something like fifteen-thousand as you 
can see [0.3] nearly sixteen-thousand [0.5] in North Thames which is north 
London [1.4] so the infection in the United Kingdom [0.2] is [0.5] pretty 
localized [2.7] there is [0.3] it's still the case [0.5] that [0.2] the 
epidemic in the United Kingdom [0.6] the highest risk f-, risk factor is still 
[0.3] homosexuality [1.3] it's still true that more homosexuals many more 
homosexuals than heterosexual [0.4] spread [1.3] but [0.2] as you can see from 
one of the tables [0.4] heterosexual spread is starting 
to incur [0.9] so there is depending again on the area in the country where you 
are there is a finite risk of heterosexual spread of this disease [1.2] if you 
start having large numbers of sexual partners [1.6] and just as it was the case 
in the homosexual spread in North America that i talked about yesterday [0.6] 
the same is true in heterosexual spread [0.8] in unprotected sex [0.4] the more 
partners you have [0.3] the greater is your risk of contracting the disease [0.
6] it's a straightforward [0.3] linear relationship one against the other [1.4] 
okay [0.9] all right i [0.3] i'll stop a little bit early because i've reached 
a natural break point [0.5] and i'll continue tomorrow [1.3] when i shall start 
talking about the virus that causes this disease [0.4] rather than the disease 
itself [0.9] thanks very much indeed