HIV is a retrovirus that causes AIDS by profoundly weakening the immune system through depletion of CD4+ T cells. It is transmitted via bodily fluids and can be passed from mother to child during pregnancy, delivery, or breastfeeding. While HIV infection may not cause symptoms for years, it can ultimately lead to AIDS if left untreated. Common opportunistic infections associated with AIDS include Pneumocystis pneumonia, toxoplasmosis, and various fungal and bacterial infections.

2. “Disease caused by retrovirus
human immunodeficiency virus (HIV)
and characterized by
profound immunosuppression
that leads to
opportunistic infections,
secondary malignancies, and
neurological manifestations”.
AIDS:

3. HIV is the virus that
causes AIDS.
A person can look and
feel healthy even if they
have HIV.
A person with HIV can
pass the virus to
others.
HIV weakens the body’s
ability to fight infection,
making a person very
sick. This is called AIDS.
It can take years for a
person infected with HIV
to develop AIDS
A person with AIDS can
still pass HIV to others.

4.  Born on 1982 in Africa, origin from monkeys/
chimpanzees…How to humans??? God knows.
 Growth-- within no time; spreads faster than Air/ fire!!!
 So rapid is the growth—by the time its immunology is
described, it will be out dated..,
 Where is AIDS?????? At your home door !!! Close door !! Take
care.
 Has remarkable ability to cripple the host defenses.

5. 1. Homosexuality:
2. Intravenous drug abusers:
3. Multiple sexual partners: heterosexual contacts:
4. Hemophiliacs: receiving f-VIII/IX
5. Recipients of blood/ blood components.
6. Transplacental:
How HIV spreads??

6.  In utero: Transplacental spread
 During delivery: through an infected birth canal
 After birth: ingestion of breast milk
 Chance of perinatal transmission: 25%
 With anti-retroviral treatment –reduced mother to
child transmission.

7.  HIV- 0.3%.., HbsAg-30%
 Antiretroviral treatment within 24 to 48 hours of needle stick
can reduce the risk of infection eightfold.
 Use universal safety precautions: Handle blood/body fluids as
if all cases are HIV positive !!

8.  Coughing
 Sneezing
 Insect bites
 Casual touch
 Hugging
 Public baths/ public telephones
 Hand shakes
 Sharing cups, glasses, plates or other utensils,
 Kissing
Remember: HIV is NOT transmitted by:

9. HIV can not be passed
through
“casual” contact
• Hugging, kissing, holding hands, or sharing
utensils is not risky
• Fluids like saliva, urine, or tears do not
transmit HIV

10.  Retrovirus; lentivirus family.
 HIV-1, and HIV-2.
 HIV-1 mc in US; HIV-2 mc in India, West Africa.
 Virion– Spherical; lipid envelope present outside is derived from
host cell membrane.
Structure of HIV:

11.  Major capsid protein- p24;
 p24– most readily detected viral antigen; and hence, the target
for diagnosis of HIV infection by ELISA.
 Three important viral enzymes—protease, reverse
transcriptase, and integrase.
 Two important viral glycoproteins—gp120 and gp41: critical
for viral infection of cells.

12.  Two major target organs for HIV: Immune system and Central
nervous system.
 Profound immunosuppression, primarily affecting cell-
mediated immunity, is the hallmark of HIV.
 Severe loss of CD4+ cells, and impaired function of surviving
T-cells.
 Also infects Dendritic cells and macrophages.

13.  Semen, vaginal secretions, cervical epithelium.
 Both within lymphocytes and cell free status
 Enters body through abrasion in skin/ oral mucosa/ rectal
mucosa.
 Enters circulation through blood vessels breached by
trauma, into Dendritic cells or CD4+cells within mucosa.
Where HIV is present??

15.  Acts as gate keeper for initial entry of virus.
 Acts as reservoir of infection.
 Site of multiplication : viral production factory!!
 Acts as safe vehicle for viral transport!!

17.  PROTOZOAL:
-Cryptosporidiosis
-Pnuemocytosis
-toxoplasmosis
 FUNGAL:
-Candidiasis
-Cryptococcosis
-Coccidiomycosis
-Histoplasmosis
 BACTERIAL:
Mycobacterial infection
Nocardiosis
Salmonella infection
 VIRAL:
CMV
HSV
Varicella Zoster virus
JC virus- PML.

18.  Kaposi sarcoma
 B-cell Non-Hodgkin lymphoma
 Body cavity lymphomas.
 Primary lymphoma of brain
 Invasive carcinoma of cervix

19. HIV
Counseling &
Testing

21. ABCs of HIV prevention
Abstinence from sex and needle use. This is the only
100% safe way to prevent HIV.
Best to have only one partner.
Condom use if you have sex.