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Human Immunodeficiency Virus (HIV) infection an uprising case in Porto Novo?




Enviado por PETER UBAH OKEKE



  1. Abstract
  2. Introduction
  3. Classification of HIV
  4. Replication of HIV
  5. Epidemiology
  6. Transmission of HIV
  7. Clinical features of HIV
    disease
  8. Status
    of human immunodeficiency virus patients
  9. Materials and method
  10. Results and discussion
  11. Discussion and conclusion
  12. References

Abstract

Aims: To study and monitor the HIV
prevalence within a time period in Porto Novo
municipality.

Materials and Methods: A total of 947 blood
samples were tested for HIV-1 and HIV-2 using Determine and
Bioline techniques between 2005 to 2008 or for 42 months aged 18
to 70 years.

Results: Six samples (2.8%) were HIV
positive for the men category, four samples were positive for
HIV-1 while two were positive for HIV-2. In women category, Nine
samples were positive for HIV making 1.2%, five samples were
positive for HIV-1 and two samples each were positive for HIV-2
and HIV-1 + 2 respectively.

Conclusion: More education is needed to
instruct and remind the population on preventive measures and
this includes; the practice of safe sex using condoms, durex and
keep faithful to only a partner

Keywords: HIV, Uprising, case, Porto
Novo.

Corresponding Author: Peter Ubah
Okeke

School of Sciences &
Engineering

Atlantic International University
Hawaii-USA.

Introduction

Human immunodeficiency virus (HIV) causes
progressive impairment of the body"s cellular immune system,
leading to increased susceptibility to infections and tumours and
the fatal condition AIDS (acquired immunodeficiency syndrome).
There are two main variants of the virus: HIV – 1 which causes
most HIV infections and HIV – 2 which is found mainly in West
Africa.

Aids was first recognized in the United
States in 1980-1981 when homosexual men were found to have
unusual infections and tumours suggesting and underlying
deficiency in their cell – mediated immunity. When the recipients
of some blood transfusions and people using intravenous drugs,
like cocaine and heroin, developed similar problems, it became
clear that AIDS was caused by an infectious agent.

However in 1983 – 1984, HIV was shown to be
the cause of AIDS. Using special techniques HIV can be cultured,
and when sought has been isolated from lymphocytes taken from
persons with AIDS and those who are HIV antibody positive.
Although evidence exists to show that HIV has been present in
humans for 15-29 years, the exact origins of the virus in not yet
know.

Infection with HIV is now global, with many
of those infected being heterosexual young men and women living
in developing countries. The world health organization has
described the AIDS situation as a global health emergency which
requires global collaboration and action.

Classification of
HIV

HIV belongs to the family of viruses called
retroviruses and subfamily lentiviruses.

Retroviruses are single-stranded RNA
(ribonucleic acid) viruses that contain the enzyme reverse
transcriptase. This enzyme is an RNA – directed DNA – polymerase
that seems to possess ribonuclease activity. It enables the RNA
of the virus to produce a DNA (deoxyribonucleic acid) copy of
itself in order to become integrated and replicate in host
cells.

Currently two genetically and
immunologically distinct human immunodeficiency viruses are
recognized as causing HIV disease and AIDS. They are:

  •   HIV – 1

  •   HIV – 2

Replication of
HIV

HIV may infect any cell bearing CD4+
antigen receptor. Such cells are mainly the helper – inducer
subsets of T – lymphocytes referred to as T4 lymphocytes. CD4+
antigen is also found on 5 – 10% of B – lymphocytes, 10 – 20% of
tissue macrophages and up to 40% of circulating monocytes. It is
thought that macrophages and monocytes are important reservoirs
of HIV. Monocytes are able to carry the virus to various organs
in the body such as the lungs and brain.

Epidemiology

HIV – 1 is responsible for most HIV
infections in Western Europe, North America, Australia and New
Zealand and throughout most of Sub-Saharan Africa.

HIV – 2 is currently found mainly in West
Africa from Cape Verde islands to Benin with highest prevalence
being in southern Senegal and Guinea Bissau. About equal
frequencies of HIV – 1 and HIV – 2 can be found in Ghana,
Nigeria, Cote d"Ivoire, Mali and Burkina-Faso.

Infections with HIV – 2 found outside of
West Africa can usually be traced back to a West African contact.
Though such contacts, HIV – 2 is thought to have been introduced
into Angola, Mozambique and Brazil.

Both HIV – 1 and HIV – 2 are spread in the
same way and both have the same consequences that are both cause
AIDS. It appears that while about 50% of people infected with HIV
– 1 will develop AIDS within about 7 – 8 years, the incubation
time for HIV – 2 may be considerably longer and some infections
may be less severe.

In developing countries, most of those
infected with HIV – live in the cities. In general the prevalence
of HIV is low in remote areas except where civil war, break up of
families, and movements of the population have spread the virus
into rural areas, for example in Mozambique and
Uganda.

Transmission of
HIV

HIV is present in semen, vaginal/cervical
secretions and blood and these are the main vehicles by which the
virus is transmitted. The virus may also be present in saliva,
tears, Urine, breast milk, cerebrospinal fluid and infected
discharges, but these are not the vehicles by which HIV is
spread. Epidemiological facts do not support the idea that HIV is
transmitted through water or food, sharing eating utensils,
coughing or sneezing, toilets, swimming pools, insects bites,
shaking hands or other casual contact, otherwise all age groups
would be infected especially young children and elderly
people.

There is therefore no public health reason
for restricting HIV infected persons from employment, training,
schooling or housing. There is no justification for taking any
discriminatory measures based solely on the fact that a person is
suspected or know to be seropositive

However, throughout the world, the group
most affected are sexually active men and women in their 20s to
40s, reflecting the fact that HIV is predominantly sexually
transmitted in developing countries the main routes of
transmission are as fallows:

  •  - Hetero or homo sexual
    intercourse

  •  - mother to child transmission or
    vertical transmission

  •  - Blood transfusion

  •  - Dirty needles

  •  - Contaminated objects used in
    circumcision in some parts of African

  •  - Sexually transmitted diseases
    have higher risks of contamination.

Clinical features
of HIV disease

Once infected with HIV, a person usually
remains well for several years before developing problems. The
person tends to become progressively ill as their immune system
becomes increasingly damaged. Infection with HIV leads to severe
immune suppression as the T4 lymphocytes are reduced in number
and cease to perform their essential role in bringing about and
regulating the body"s immune responses.

CLASSIFICATION OF HIV
INFECTIONS

The Centre of Disease Control (CDC) in the
United States has proposed the following classification system
for people with HIV infection:

Group I – sero conversion
illness

Group II – asymptomatic

Group III – persistent generalized
lymphoadenopathy

Group IV – symptomatic HIV
disease

GROUP I

Soon after becoming infected with HIV, a
few people (10%) have a glandular fever-like illness with sore
throat, skin rash, fever and enlarged lymph glands. This is
called a seroconversion illness because it occurs at a time when
the infected person is first making antibodies against HIV.
Following this the person is described as being seropositive. The
illness passes off after a few weeks and the person becomes
asymptomatic.

GROUP II

Most people remain completely well after
acquiring HIV and seroconverting. They can remain well for many
years before developing AIDS but during this time they are
infections.

GROUP III

Many HIV infected people, although
otherwise well, develop generalized swelling of their lymph
nodes, usually in the neck and under the arms. The lymph nodes
are usually about 1-2 cm in diameter mobile and not
tender.

GROUP IV

After a variable period of time, most
people in groups I to III developed symptoms and signs due to HIV
or its consequences and are then classified as belonging to Group
IV. Most clinical problems are due to HIV causing a progressive
decline in the bodies" immune responses, leading to opportunistic
infections and some tumours. Sometimes HIV itself may cause
damage to the body directly. Group IV includes those with AIDS or
AIDS related complex.

Please note that following infections with
HIV and before the appearance of circulating markers of
infection, there is a "Window Period" of varying length, during
which the infection becomes established. The window period is an
important issue in blood screening as it is the period during,
which screening tests will be unable to detect a potentially
infectious donation. The window period could take up to 3
months.

The number of CD8+ lymphocytes increases
and this helps to reverse the CD4+ to CD8+ ratio. A temporary
drop in CD4+ cells is also observed, and an asymptomatic
thrombocytopenia may occur during this phase. A viremia occurs
but is cleared via the action of cytotoxic T –
lymphocytes.

An asymptomatic phase or latent phase may
last for months or years. The length of this phase is dependent
on multiple factors including the dose of the virus, the route of
the infection, the genetics of the host, and the immune response
generated by the host. The clinical latency, described here is
not associated with viral latency. The virus still continues to
replicate in the lymphoreticular tissue.

Laboratory signs that immune activation is
occurring include elevated levels of Beta-2 microglobulin
neopterin and interleukin 2. The centre for disease control in
Atlanta stated that adolescents and adults with HIV are
classified as having AIDS if their CD4+ lymphocyte count is under
200 uL and or if their CD4+ T lymphocyte percentage is less than
14. In addition, HIV infected patients whose CD4+ count is less
than 200 / uL who acquire certain infections diseases or
malignancies are also classified as having AIDS.

Status of human
immunodeficiency virus patients

The CD4+ count, viral load and the presence
of immune activation markers can be used to predict the
progression of the disease. An abrupt or gradual decline in the
CD4+ count usually indicates that clinical disease will
follow.

Approximately 87% of patients who have a
CD4+ count of less than 200/uL developed AIDS within 3 years.
Where as patients whose counts are between 200 and 480 convert to
AIDS at about a 46% rate within 3 years. Finally those patients
with a CD4+ count above 500/uL developed AIDS at a 16% rate for
the some time period.

Plasma viremia has also been directly
linked to clinical stages. In acute primary infection the viral
load rises to about 5 x 106 virions/mL and then drops back to 8 x
104 / virions/mL during the asymptomatic stage. The viral load
rises to 3.5 x 105 virions/mL during the early symptomatic stage
and continues to climb to about 2.5 x 106 virions/mL when AIDS is
diagnosed.

Viral load and CD4+ cell counts are used to
monitor the effectiveness of antiviral therapy. Combinations of
various drugs including nucleoside analogs, protease inhibitors
and non nucleoside analogs are administrated to the patient.
Often the viral load decreases in about 2 weeks and if the
treatment is successful the maximal effect should occur by 6
months. The viral load level at the 6 month point is referred to
as the set point.

The patient should then be monitored for
viral load every 3 to 4 months. If the viral load rises above the
set point, the patient should be switched to a new combination of
drugs.

An indirect method to measure virus
productions is to monitor immune activation markers. Increases of
B2 micro globulin in plasma or increases in neopterin in the
urine correlate with the degree of lymphocyte activation and also
indicate progression to disease in HIV patients.

Materials and
method

A total of 947 blood samples were collected
at random from individuals apparently healthy and from suspected
patients mainly adults(18 to 70 years) for a period of 42 month
(2005 to 2008). A 2 cc of blood samples were collected into a BD
vacutainer tubes and after centrifugation, plasma samples were
obtained for the HIV 1 and HIV 2 testing.

MATERIALS

A complete test kit of determine HIV 1 and
HIV 2 was used for this test, and a kit of Bioline standard
diagnostics SD HIV1 and HIV2 and Automatic pipette calibrated
from 5 to 50ul.

METHOD

The manufacturers instruction was
completely followed in both tests (Determine and Subsequent
Bioline) and positive and inconclusive samples were confirmed by
the ELISA test kits (Enzyme linked immunosorbent Assay)- at the
hospital of Dr.Baptista De Sousa in SãoVicente Cape Verde,
Sensitivity and specificity are important characteristics which
describe the accuracy of HIV antibody assay results, in this
study, the assay used was 99% sensitive, this is crucial because
samples containing HIV antibody at low level was not missed and
due to its high specificity, sera not containing HIV antibody was
correctly detected as HIV negative.

METHOD TEST DETERMINE

  •  1. Remove the protective foil
    cover from each test.

  •  2. For serum or plasma samples,
    apply 50µL of the sample using precision pipette to the
    sample pad marked by the arrow symbol.

  •  3. Wait for a minimum of 15
    minutes (up to 60 minutes).

  •  4. Read the results.

QUALITY CONTROL

To ensure assay validity, a procedural
control is incorporated in the device and is labelled CONTROL. If
the control bar does not turn red by assay completion, the test
result is invalid and the sample be retested.

BIOLINE TEST

1. Remove the test device from foil
pouch; place it on a flat, dry surface (using a capillary
pipette)

2. Add 10µL of plasma or serum
specimen into the sample well labelled (S).

3. Add 4 drops (about 120µL) of assay
diluents into sample well (S).

4. As the test begins to work, you will see
purple color move across the result window in the centre of the
test device.

5. Read results and control in 5 to 20
minutes. Please do not read results after 20 minutes, reading too
late can give false results.

Results and
discussion

Population

N.º of tests
-n

Positive for HIV-1

Positive for HIV-2

Positive for
HIV-1/2

Total positive

Men

218

4

2

0

6

Women

729

5

2

2

9

Total

947

9

4

2

15

Table 1: Presents the summary of all
events occurred during the project work of 42 months (2005 to
2008) in Porto novo field work.

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Table 2: Presents a graphical
representation during the 42 months field research work in Porto
Novo.

Discussion and
conclusion

A total of 947 samples were tested for a
period of about 42 months, a total of 218 samples were men while
729 samples were women. However, among the men tested, 6 men were
recorded laboratorial as HIV positive making a percentage of 2.8%
of the samples tested. Out of the positive samples, two were
clinically presenting generalized dermatitis while one was
venereal disease research laboratory (VDRL) screening tested
positive with a clinical features of syphilis, one person
positive for HIV-1 was presenting exclusive weight loss. And the
rest HIV positive were apparently healthy persons without any
clinical features and did not know that they were
infected.

In the women category, a total of samples
tested recorded 9 HIV positive laboratorial confirmed cases
making a percentage of 1.2% of the women samples tested. Five
women were positive for HIV-1, two women were positive for HIV-2
and also two others showed positive for both HIV-1 and HIV-2. A
woman positive for HIV-1+2 was clinically presenting chronic
diarrhoea of more than 2 months and a woman positive for HIV-2
was of risky sexual behaviour. The virulence of the human
immunodeficiency strains have been reported to be different with
HIV-1 being more virulent. The type of HIV at the increase in
Porto Novo locality is HIV-1. In the men population tested, four
men were positive for HIV-1 while in the women population tested,
five women were positive also for HIV-1.

However in a study carried out in 1987
among sex workers in several Cape Verde islands recorded HIV
prevalence at about 2% and another study carried out in urban
areas of Praia in 1988 showed 1.4% HIV prevalence in age group 15
to 55 years. All these studies in the 1980s showed only HIV-2
(and no HIV-1 isolated)- United Nations study group on acquired
immunodeficiency syndrome (UNAIDS) reported in African continent,
country by country has published this work about the incidence of
HIV infection in Cape Verde.

However the situation in Porto Novo is
purely different from that of UNAIDS of the 1980s, because most
of the population tested showed higher incidence of HIV-1 than
HIV-2 and this could be due to the more competitive nature of
Hiv-1 to that of Hiv-2 . A positive HIV test is neither
diagnostic of AIDS nor any AIDS – related condition but only an
indication of infection with the virus.

The percentage of patients with positive
HIV antibody test who actually develop AIDS differs from one
geographical area to another. Predisposing factors for
progression to AIDS are poorly understood. They are thought to
include malnutrition, overall health and constitution of the
patient, individual genetically determined vulnerability to
chronic HIV infections and the occurrence of other viral or
serious infection which can hasten immune suppression
particularly in high risk persons.

The anxiety of progression to AIDS causes a
lot of stresses which may in it hasten the onset of AIDS, the
Porto Novo experience showed that the infection of the pandemic
virus is sub control and that the sexually active group aged 20
to 50 is more involved. In this study, persons tested has no
history of past blood transfusion and toxic dependency or
intravenous drug users and this showed that unprotected sex
remains the route of most transmission of the deadly
virus.

Conclusion

In conclusion, this work is for the purpose
of monitoring the prevalence of HIV infection among Porto Novo
inhabitants and as a vigilante screening for voluntary blood
donors and persons who are healthy and also from patients
presenting clinical signs and symptoms suggested by the physician
as a watch out signs for HIV and or AIDS. Although there are many
signs connected to HIV which is mostly noted such as chronic
diarrhoea, sexually transmitted diseases (syphilis,chancroid,and
gonorrhoea),fungal infections,meningitis,tuberculosis,pneumonia
etc. The percentage recorded in this work follows almost what the
UN-AIDS (1980) reported. The incidence of HIV-1 mostly seen now
could be as a result of more competitive nature of Hiv-1 to that
of Hiv-2. In Cape Verde, we could see that the HIV pandemic is
under control because of various governmental and
non-governmental programs aimed at reducing the infection and a
percentage of 2.8%of men samples tested and that of 1.2%of women
samples tested, in a total of 947 samples were not alarming. And
in all there are nine tested positive for HIV-1,(four men and
five women respectively).It takes a total dedication of all the
officers of the health sector, government and the public to
continue in this fight against the AIDS insurgence and laboratory
should continue to be on the watch in testing of both apparently
healthy and suspected persons. It is obvious that blood donors
should be totally screened and accepting blood transfusion
remains strict only on the last resort because blood accepted
during the window period must be positive in the circulation of
the patient no matter the result of the screening test conducted
on such blood before transfusion. The young and the old should
continue to practice safe sex and to remain faithful to only a
sex partner and perform test of HIV on intended new partners. HIV
testing must remain paramount to the candidate of marriage and
the local court registry and churches should incorporate HIV
screening tests as one of the factors for qualification of
marriage, both partners must present the results of HIV testing
from recognized laboratories or agencies. This will go a long way
in preventing the pandemic virus from circulating.

However, governmental agencies should make
provisions for easy access to sex education and incorporate same
in schools and universities and durex or condom will be freely
accessible to the public especially in African continent. Hotels
receiving travelers must have the publicity of HIV/AIDS openly in
public areas.

References

Anderson S. et al (1997: Field evolution of
alternative testing strategies for diagnosis and differentiation
of HIV1 & HIV2 infection in HIV1 & HIV2 prevalent areas,
AIDS, II: 1815 – 1822

Bain B. J (1997): The haematological
features of HIV infection. British journal Haematology, 99,
1-8.

Bours, et al (1995): The HIV type I CD4
receptor and its central role in promotion of HIV1 infection.
Microbiol Rev 59 (I): 63-93

Cleminti, M, et al (1996):Clinical use of
quantitative molecular methods in studying HIV type 1 infection
,Clinical microbial rev. 9 (2): 135-147.

Eve, M, et al (1996):Estimated risk of
transmission of HIV by screened blood in the USA, journal of
medicine vol. 333 n. º 26.

Health link (1999):HIV testing; a practical
approach

Holms, K. K. et al (1990): Sexually
transmitted diseases, 2nd Ed. New York, McGraw Hill

Levy J. A. et al (1994): HIV and
pathogenesis of AIDS American Soc. For microbiology

Mahon C.R. et al(1995) ; HIV status.
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Meda, N, et al (1999): Serological
diagnosis of HIV in Burkina Faso; reliable, practical strategies
using less expensive commercial test kits. Bull of world health
org. 77, 79 731-739.

Saac, M. S. et al (1996): HIV viral load
markers in clinical practice, nature medicine, vol. 2 N. º
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Schochetman G. et al (1992): AIDS testing:
methodology and management issues. New York, Springer.

The Biomedical sciences bulletin vol.
2,pg13,1999

Weekly Epid. Record 65: 281-283

Wilkinson D. et al (1997): In – site HIV
testing in resource poor settings; is one rapid test enough?
AIDS, II, 377-381

World Health Org. (1990): Acquired
immunodeficiency syndrome (AIDS)

 

Author:

Okeke Peter Ubah

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