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PHT 112: HIV AIDS Determinants, Prevention and Management
INTRODUCTION
Human behavior plays a key role in most of the disease condition in life.
a) Socialization; is a life long process through which individuals in a society develop an
awareness of social norms and values; achieve destine of self.
b) Norms: Rules and expectations conduct which either prescr ibes a given type of behavior, or
forbid it.
c) Values: Culturally defined standards held by human individuals or groups about what are
desirable, proper, beautiful, and good or bad that save as broad guidelines for social life.
d) The individualistic int erpretation of disease places emphasis on the individual as responsible
for his or health status.
Health compromising behavior by individual is the main factor in health.
TOPIC 1: OVERVIEW OF HIV & AIDS
The origin of HIV AIDS
Human Immunodeficiency Virus
HIV is a lent virus, which is a class of viruses that attack the immune system. Lent viruses
are in turn part of a larger group of viruses known as retrovir uses. The name 'lent vir us'
literally means 'slow virus' because they take such a long time to produce any adverse
effects in the body.
These viruses have been found many different animals including cats, sheep, cattle and
horses A retrovirus is a virus which has a genome consisting of two RNA molecules,
which may or may not be identical. It relies on the enzyme reverse transcriptase to
perfor m the reverse transcr iption of its genome from RNA into DNA, which can then be
integrated in the host s genome with an integrase enzyme.
Simian Immunodeficiency Virus
It is now generally accepted that HIV is a descendant of a Simian Immunodeficiency
Virus because certain strains of SIVs bear a very close resemblance to HIV-1 and HIV-2,
the two types of HIV. HIV-2 for example corresponds to SIVsm, a strain of the Simian
Immunodeficiency Virus found in the sooty mangabey ( also known as the green monkey) ,
which is indigenous to western Africa.
The more virulent strain of HIV, namely HIV-1, was until recently more difficult to place.
Until 1999, the closest counterpart that had been identified was SIVcpz, the SIV found in
chimpanzees. However, this virus still had certain significant differences from HIV.
Researchers concluded that wild chimps had been infected simultaneously with two
different simian immunodeficiency viruses which had "viral sex" to form a third virus that
could be passed on to other chimps and was capable of infecting humans with HIV AIDS.
These two different viruses were traced back to a SIV that infected red- capped
mangabeys and one found in greater spot-nosed monkeys.They believe that the
hybridization took place inside chimps and that humans had become infected with both
strains of SIV. After they hunted and killed the two smaller species of monkey.
Zoonosis
It refers to any infectious disease that may be transmitted from other animals, both wild and
domestic, to humans. It has been known for a long time that certain vir uses can pass between
species. Because chimpanzees obtained SIV from two other species of apes shows just how easily
this cr ossover can occur. As animals ourselves, we are just as susceptible.
1
, The various theories explaining the origin of HIV AIDS
1. The “Hunter” Theory
The most commonly accepted theory. SIVcpz was transferred to humans as a result of
chimps being killed and eaten, or their blood getting into cuts or wounds on a hunter.
Normally a hunter s body could have fought off the SIV, but in a few cases it adapted to
its new human host and evolved into HIV. Early on, there were several different strains of
HIV, each having a slightly different genetic makeup. The most common being HIV-1
group M
Each time it was passed from a chimp to a human it adapted differently therefore cr eating
a different genetic makeup and becoming a new strain.
In a study of 1099 individuals in Cameroon it was discovered that 10 (1%) wer e infected
with SFV (Simian Foamy Virus), which, like SIV, was pr eviously thought only to infect
chimps.
These infections were all thought to have come fr om butchering and eating of monkey
and ape meat.
2. The Cont aminat ed Needle Theory
This is an extension of the Hunter Theory.
In the 1950s the use of disposable, plastic needles became common ar ound the world as a
cheap and sterile way to administer medicine. However, in Africa the enormous amount of
needles needed to give inoculations and other medication would have been very costly.
It is likely that one syr inge would have been used to give multiple people injections
without sterilizing the needle. This would rapidly have transferred any viral particles from
one person to another, creating huge potential for the virus to mutate and replicate in each
new individual it entered, even if the SIV within the original per son infected had not yet
converted to HIV.
3. Oral Polio Theory
HIV-1 evolved from accidental vaccine contaminations and subsequent transmissions to
African villagers. In his book, The River, the journalist Edward Hooper suggested that
HIV could be traced to the testing of an oral polio vaccine called Chat, given to about a
million people in the Belgian Congo , Rwanda and Burundi in the late 1950s.
Hooper's belief is that Chat was grown in kidney cells taken from local chimps infected
with SIVcmz.
The vaccine was analyzed and in April 2001 it was announced that no trace had been
found of either HIV or chimpanzee SIV. A second analysis confirmed that only macaque
monkey kidney cells, which cannot be infected with SIV or HIV, were used to make
Chat. Most have taken this evidence to mean that the OPV vaccine theory is not possible.
4. The “Heart of Darkness” Theory
This is a more recent theory based on the basic 'hunter' premise, but more thoroughly
explains how this original infection could have led to an epidemic.
It was first proposed in 2000 by Jim Moore, an Amer ican specialist in pr imate behavior,
during the late 19th and ear ly 20 th century, much of Afr ica was ruled by colonial forces.
Compiled by Ziruel Siko. Contact 0713395497 from eLearning downloads. Copy rights reserved.
2
.
, During this time many Africans were forced into labor camps where sanitation was poor,
food was scare and physical demands were extreme.
Moore proposed that these factors alone would have been sufficient to create poor health
in anyone, so SI V could easily have infiltrated the labor force and taken advantage of their
weakened immune systems to become HIV. The most likely possibility he says was a
stray and perhaps sick chimpanzee with SIV that would have made a welcome extra
source of food for the workers.
Moore also believes that many of the laborers would have been inoculated with un-ster ile
needles against diseases such as smallpox and that many of the camps actively employed
prostitutes to keep the wor kers happy, creating numerous possibilities for onward
transmission.
5. The Conspiracy Theory
Some people believe HIV is a “conspiracy” theory or that it is man-made. In a recent US
survey showed that a significant number of Afr ican Americans believe that HIV was
invented as part of a biological warfare program designed to wipe out large numbers of
Afr ican Americans and Homosexuals.
They believe this was done under the US Federal “special cancer virus program (SCVP),
possibly with the help of the CIA. Some even believe it was spread (either deliber ately or
inadvertently) to people all over the world through the smallpox inoculation pr ogram, or
to gay men through Hepatitis B vaccine trials.
Although none of these theories can be definitively disproved, they clearly ignore the link
between SIV and HIV and the fact that the virus has been seen in humans as far back as
1959. There was also a lack of genetic-engineering technology available when AIDS fir st
appeared in Humans.
Factors Contributing to High HIV Prevalence in Children in Sub-Saharan Africa
High prevalence of infection in women of childbearing age
Low coverage of PMTCT interventions
Lack of male partner involvement
Stigma
Impact of AIDS Epidemic on Children
AI DS impacts children in many ways;
Increased infant and childhood mor bidity and mortality
Increase in number of orphaned children
Increased depr ivations in various forms;
Mental
Psychological
School dropouts
Abuse : Physical, Sexual
Did HIV Come f rom Africa?
Given the evidence of all the different studies, it is likely that Afr ica was indeed the
continent wher e the transfer of HIV to humans first occurred. Monkeys fr om Asia and
South America have never been found to have SIVs that could have caused HIV in
humans. However, who exactly spread the virus from Afr ica, to America and beyond
remains a mystery.
3
Compiled by Ziruel Siko. Contact 0713395497 from eLearning downloads. Copy rights reserved.
, It is quite possible that separate strains of the virus could have been developing in a
number of different countries year s before the first cases were ever officially identified,
making it virtually impossible to trace one single source. Some of the Earliest Instances of
HIV in Humans.
A plasma sample taken in 1959 from an adult male living in what is now the Democratic
Republic of Congo. This suggests that HIV-1 was fir st introduced into humans
Ar ound 1940s or the 1950s, which is much earlier than previously though HIV found in
tissue samples of an American teenager who died in St. Louis in 1969 HIV found in tissue
samples fr om a Norwegian soldier who die around 1976.
In January 2000 a studied conducted by Bette Korber of the Los Alamos National
Laborator y suggested that the first case of HIV-1 occurred around 1930 in West Afr ica.
This finding was based on a computer model of HI V s evolution.
How Did the Epidemic of AIDS Spread So?
1. Blood Transfusions : As they became more common in medical practice the demand
For blood became very high. At one point in the US donors were paid for blood
donations. Which attracted those most desperate for cash and blood donations were not
scanned for HI V because doctors were unaware of how the virus was transmitted.
Sometimes these donations wer e sent overseas as well.
2. Drug Use : In the 1970s Heroin use increased dr amatically following the Vietnam War and
Middle Eastern conflicts. The development of “shooting galleries”, wher e drugs and
equipment were sold allowed easy access of IV drugs, again with People being unaware of
how easily the disease was spread.
3. Travel : Escalated in the late 1970s and ear ly 1980s with many young men making the
most of the homosexual revolution. In Africa it possibly spread along truck routes through
cities within the countr y itself.
Historical background
1981 - doctors in US recognized PCP in homosexual males, a condition previously
unreported in healthy adults
Later recognized that patients all were immunosuppressed
1983/4 - scientist described the cause of the syndrome as a retrovirus
Lymphadenopathy Associated Virus (LAV)
AI Ds Associated Retrovir us (ARV)
Human T-lymphotrophic Virus ( HTLV- )
In Kenya the first case described in 1984
1986 - Human Immunodeficiency Virus (HIV) accepted as international designation for
the retrovirus in a WHO consultative meeting
Impact of HIV on Morbidity and Mortality Secondary to Other Infect ions
People with HIV/AIDS are susceptible to other infections
Due to lowered immunity
High HIV prevalence increases the pool of people with suppressed immunity
Other infectious conditions within such a population find a highly susceptible group of
people.
HIV infected people have rates of both TB and LRTI much higher than the HIV negative
4
Compiled by Ziruel Siko. Contact 0713395497 from eLearning downloads. Copy rights reserved..
PHT 112: HIV AIDS Determinants, Prevention and Management
INTRODUCTION
Human behavior plays a key role in most of the disease condition in life.
a) Socialization; is a life long process through which individuals in a society develop an
awareness of social norms and values; achieve destine of self.
b) Norms: Rules and expectations conduct which either prescr ibes a given type of behavior, or
forbid it.
c) Values: Culturally defined standards held by human individuals or groups about what are
desirable, proper, beautiful, and good or bad that save as broad guidelines for social life.
d) The individualistic int erpretation of disease places emphasis on the individual as responsible
for his or health status.
Health compromising behavior by individual is the main factor in health.
TOPIC 1: OVERVIEW OF HIV & AIDS
The origin of HIV AIDS
Human Immunodeficiency Virus
HIV is a lent virus, which is a class of viruses that attack the immune system. Lent viruses
are in turn part of a larger group of viruses known as retrovir uses. The name 'lent vir us'
literally means 'slow virus' because they take such a long time to produce any adverse
effects in the body.
These viruses have been found many different animals including cats, sheep, cattle and
horses A retrovirus is a virus which has a genome consisting of two RNA molecules,
which may or may not be identical. It relies on the enzyme reverse transcriptase to
perfor m the reverse transcr iption of its genome from RNA into DNA, which can then be
integrated in the host s genome with an integrase enzyme.
Simian Immunodeficiency Virus
It is now generally accepted that HIV is a descendant of a Simian Immunodeficiency
Virus because certain strains of SIVs bear a very close resemblance to HIV-1 and HIV-2,
the two types of HIV. HIV-2 for example corresponds to SIVsm, a strain of the Simian
Immunodeficiency Virus found in the sooty mangabey ( also known as the green monkey) ,
which is indigenous to western Africa.
The more virulent strain of HIV, namely HIV-1, was until recently more difficult to place.
Until 1999, the closest counterpart that had been identified was SIVcpz, the SIV found in
chimpanzees. However, this virus still had certain significant differences from HIV.
Researchers concluded that wild chimps had been infected simultaneously with two
different simian immunodeficiency viruses which had "viral sex" to form a third virus that
could be passed on to other chimps and was capable of infecting humans with HIV AIDS.
These two different viruses were traced back to a SIV that infected red- capped
mangabeys and one found in greater spot-nosed monkeys.They believe that the
hybridization took place inside chimps and that humans had become infected with both
strains of SIV. After they hunted and killed the two smaller species of monkey.
Zoonosis
It refers to any infectious disease that may be transmitted from other animals, both wild and
domestic, to humans. It has been known for a long time that certain vir uses can pass between
species. Because chimpanzees obtained SIV from two other species of apes shows just how easily
this cr ossover can occur. As animals ourselves, we are just as susceptible.
1
, The various theories explaining the origin of HIV AIDS
1. The “Hunter” Theory
The most commonly accepted theory. SIVcpz was transferred to humans as a result of
chimps being killed and eaten, or their blood getting into cuts or wounds on a hunter.
Normally a hunter s body could have fought off the SIV, but in a few cases it adapted to
its new human host and evolved into HIV. Early on, there were several different strains of
HIV, each having a slightly different genetic makeup. The most common being HIV-1
group M
Each time it was passed from a chimp to a human it adapted differently therefore cr eating
a different genetic makeup and becoming a new strain.
In a study of 1099 individuals in Cameroon it was discovered that 10 (1%) wer e infected
with SFV (Simian Foamy Virus), which, like SIV, was pr eviously thought only to infect
chimps.
These infections were all thought to have come fr om butchering and eating of monkey
and ape meat.
2. The Cont aminat ed Needle Theory
This is an extension of the Hunter Theory.
In the 1950s the use of disposable, plastic needles became common ar ound the world as a
cheap and sterile way to administer medicine. However, in Africa the enormous amount of
needles needed to give inoculations and other medication would have been very costly.
It is likely that one syr inge would have been used to give multiple people injections
without sterilizing the needle. This would rapidly have transferred any viral particles from
one person to another, creating huge potential for the virus to mutate and replicate in each
new individual it entered, even if the SIV within the original per son infected had not yet
converted to HIV.
3. Oral Polio Theory
HIV-1 evolved from accidental vaccine contaminations and subsequent transmissions to
African villagers. In his book, The River, the journalist Edward Hooper suggested that
HIV could be traced to the testing of an oral polio vaccine called Chat, given to about a
million people in the Belgian Congo , Rwanda and Burundi in the late 1950s.
Hooper's belief is that Chat was grown in kidney cells taken from local chimps infected
with SIVcmz.
The vaccine was analyzed and in April 2001 it was announced that no trace had been
found of either HIV or chimpanzee SIV. A second analysis confirmed that only macaque
monkey kidney cells, which cannot be infected with SIV or HIV, were used to make
Chat. Most have taken this evidence to mean that the OPV vaccine theory is not possible.
4. The “Heart of Darkness” Theory
This is a more recent theory based on the basic 'hunter' premise, but more thoroughly
explains how this original infection could have led to an epidemic.
It was first proposed in 2000 by Jim Moore, an Amer ican specialist in pr imate behavior,
during the late 19th and ear ly 20 th century, much of Afr ica was ruled by colonial forces.
Compiled by Ziruel Siko. Contact 0713395497 from eLearning downloads. Copy rights reserved.
2
.
, During this time many Africans were forced into labor camps where sanitation was poor,
food was scare and physical demands were extreme.
Moore proposed that these factors alone would have been sufficient to create poor health
in anyone, so SI V could easily have infiltrated the labor force and taken advantage of their
weakened immune systems to become HIV. The most likely possibility he says was a
stray and perhaps sick chimpanzee with SIV that would have made a welcome extra
source of food for the workers.
Moore also believes that many of the laborers would have been inoculated with un-ster ile
needles against diseases such as smallpox and that many of the camps actively employed
prostitutes to keep the wor kers happy, creating numerous possibilities for onward
transmission.
5. The Conspiracy Theory
Some people believe HIV is a “conspiracy” theory or that it is man-made. In a recent US
survey showed that a significant number of Afr ican Americans believe that HIV was
invented as part of a biological warfare program designed to wipe out large numbers of
Afr ican Americans and Homosexuals.
They believe this was done under the US Federal “special cancer virus program (SCVP),
possibly with the help of the CIA. Some even believe it was spread (either deliber ately or
inadvertently) to people all over the world through the smallpox inoculation pr ogram, or
to gay men through Hepatitis B vaccine trials.
Although none of these theories can be definitively disproved, they clearly ignore the link
between SIV and HIV and the fact that the virus has been seen in humans as far back as
1959. There was also a lack of genetic-engineering technology available when AIDS fir st
appeared in Humans.
Factors Contributing to High HIV Prevalence in Children in Sub-Saharan Africa
High prevalence of infection in women of childbearing age
Low coverage of PMTCT interventions
Lack of male partner involvement
Stigma
Impact of AIDS Epidemic on Children
AI DS impacts children in many ways;
Increased infant and childhood mor bidity and mortality
Increase in number of orphaned children
Increased depr ivations in various forms;
Mental
Psychological
School dropouts
Abuse : Physical, Sexual
Did HIV Come f rom Africa?
Given the evidence of all the different studies, it is likely that Afr ica was indeed the
continent wher e the transfer of HIV to humans first occurred. Monkeys fr om Asia and
South America have never been found to have SIVs that could have caused HIV in
humans. However, who exactly spread the virus from Afr ica, to America and beyond
remains a mystery.
3
Compiled by Ziruel Siko. Contact 0713395497 from eLearning downloads. Copy rights reserved.
, It is quite possible that separate strains of the virus could have been developing in a
number of different countries year s before the first cases were ever officially identified,
making it virtually impossible to trace one single source. Some of the Earliest Instances of
HIV in Humans.
A plasma sample taken in 1959 from an adult male living in what is now the Democratic
Republic of Congo. This suggests that HIV-1 was fir st introduced into humans
Ar ound 1940s or the 1950s, which is much earlier than previously though HIV found in
tissue samples of an American teenager who died in St. Louis in 1969 HIV found in tissue
samples fr om a Norwegian soldier who die around 1976.
In January 2000 a studied conducted by Bette Korber of the Los Alamos National
Laborator y suggested that the first case of HIV-1 occurred around 1930 in West Afr ica.
This finding was based on a computer model of HI V s evolution.
How Did the Epidemic of AIDS Spread So?
1. Blood Transfusions : As they became more common in medical practice the demand
For blood became very high. At one point in the US donors were paid for blood
donations. Which attracted those most desperate for cash and blood donations were not
scanned for HI V because doctors were unaware of how the virus was transmitted.
Sometimes these donations wer e sent overseas as well.
2. Drug Use : In the 1970s Heroin use increased dr amatically following the Vietnam War and
Middle Eastern conflicts. The development of “shooting galleries”, wher e drugs and
equipment were sold allowed easy access of IV drugs, again with People being unaware of
how easily the disease was spread.
3. Travel : Escalated in the late 1970s and ear ly 1980s with many young men making the
most of the homosexual revolution. In Africa it possibly spread along truck routes through
cities within the countr y itself.
Historical background
1981 - doctors in US recognized PCP in homosexual males, a condition previously
unreported in healthy adults
Later recognized that patients all were immunosuppressed
1983/4 - scientist described the cause of the syndrome as a retrovirus
Lymphadenopathy Associated Virus (LAV)
AI Ds Associated Retrovir us (ARV)
Human T-lymphotrophic Virus ( HTLV- )
In Kenya the first case described in 1984
1986 - Human Immunodeficiency Virus (HIV) accepted as international designation for
the retrovirus in a WHO consultative meeting
Impact of HIV on Morbidity and Mortality Secondary to Other Infect ions
People with HIV/AIDS are susceptible to other infections
Due to lowered immunity
High HIV prevalence increases the pool of people with suppressed immunity
Other infectious conditions within such a population find a highly susceptible group of
people.
HIV infected people have rates of both TB and LRTI much higher than the HIV negative
4
Compiled by Ziruel Siko. Contact 0713395497 from eLearning downloads. Copy rights reserved..
