2. AIDS
• DEFINITION
• This is a very serious infection caused by a virus, the human
immunodeficiency virus(HIV)
• In East and central Africa, the common HIV strain is HIV-1. HIV-2 is found in
West Africa. HIV-2 has not been reported in Tanzania
• METHODS OF TRANSMISSION:
• Vertical transmission(from mother to child)
-i) During pregnancy 20%
-ii) During delivery 10-20%
- iii) Post partum 5-10%
• The chances are higher if the mother is sick with symtoms of HIV
3. • Adolescents may acquire the disease if they are sexually active or by
intravenous use of drugs
• 3) Transfusion of infected blood with virus blood products(
transmission also occur through body fluids other than blood
• 4) Breast milk: the virus is secreted in the breast milk for babies who
are breast fed. ( the risk is higher if mixed feeding is carried out ie.
Mixing breast milk and formula milk.
• N/B No risk of infection by casual touching an infected child. Unless
blood is visible in saliva sputum, sweat nasal secretions, urine the risk
is low.
4. HIV(cont)
• PATHOPHYSIOLOGY:
• The virus enters the susceptible cell using an enzyme, reverse transcriptase
. Once in the cell it copies itself from RNA to DNA genetic material. The
viral DNA copy enters the nucleus of the host cell and becomes
incorporated into the cells own DNA using an enzyme intragrase.It now
becomes a permanent part of an infected person's nuclear protein. It
follows a latent period in the infected nucleus waiting for an external
stimulus to start reproducing
• The virus enters the body by attaching through T lymphocytes CD4 and
they mature and produce more virus and eventually leave the host cell. The
cell membrane weakens leading to the death of the infected cell
5.
6. • CLINICAL PROGRESSION OF THE DISEASE:
• Primary infection: new infection with the virus is usually not immediately
noticed. It presents with short illness and flu like symptoms such as fever
malaise enlarged lymph nodes sore throat skin rash. This is the sero-
conversion illness joint pain etc. It may last for few weeks. During this
episode there is a wide spread dissemination of the virus to different
tissues especially lymphoid system
• Symptomatic HIV: over time the immune system loses struggle to contain
the virus because the CD4 cells which protect the body are destroyed.
Opportunistic infection (Ois) set in. There will be fever, respiratory
infections, cough TB weight loss skin diseases oral thrush pain,
lymphadenopathy etc
7. • AIDS: AIDS is defined when a person with HIV develops severe
immunosuppression. – severe weight loss cancers(Kaposis sarcoma)
Criptococcal meningitis, PCP Toxoplasmosis, CMV, retinitis.
• DIAGNOSIS OF HIV INFECTION IN CHILDREN
• Majority of children get infected during pregnancy, delivery or
breastfeeding. Thus exposure to HIV continuous as the child of an
HIV- infected mother is breastfed.
• HIV infected infants may not show any signs or symptoms soon after
birth but usually develop the features in the early infant period
8. AIDS IN CHILDREN
• DIAGNOSIS OF HIV INFECTION IN CHILDREN BELOW 18 MONTHS:
• Infants born to HIV-infected women have antibodies to HIV which are
passively transferred from their mother. These antibodies can persist
until 9 to 18 months of age. Therefore a positive rapid HIV antibody
test in the infant does not confirm or exclude HIV infection.
Therefore, DNA PCR ir required in order to confirm infection in the
child less than 18 months of age. PCR test should be done at six
weeks of age or at any time there after when the child is first seen by
a healthcare worker
• - If PCR test is positive, child should be started on ART immediately
while waiting for a second HIV DNA test results
9. AIDS IN CHILDREN(cont)
• - All children with a negative results should have an HIV test at9
months of age and 12 weeks after complete cessation of breast
feeding and final rapid test at 18 months of age to confirm their
status
• - If a child is being breastfed by an HIV infected mother a negative
antibody test does not exclude HIV infection. The on going breast
feeding put the child at risk of acquiring infection
• - A single positive PCR test means the infant is presumably infected
and should be started on ART. A second DNA PCR as to confirm the
first test result test should be taken immediately after receiving a
positive test results. The second test should not delay ART initiation
10. AIDS IN CHILDREN(cont)
• - For a child thatbwas not breastfed, a single negative DNA PCR test
after the age of sis weeks excludes HIV infection.
• - For a child that has completely stopped breastfeeding for more than
3months prior to virologic (DNA PCR testing) a negative DNA PCR
excludes HIV infection.
• FACTORS THAT INCREASE THE CHANCE OF A
MOTHERVTRANSMITTING THE DISEASE TONHER CHILD.
• High maternal viral load(over 50 copies/millilitre) and a low CD4
count
