Week 7: HIV 2

I.              Control

a.    Need

                                              i.     Pandemic in >15 years

                                            ii.     25-30 years reduced lifespan in Africa

                                          iii.     95+ infections in developing world

                                           iv.     Most productive age group most affected

                                             v.     U.S. growing mostly in African American women

b.    Why it continues:

                                              i.     Poverty

                                            ii.     Limited access to healthcare

                                          iii.     Lack of diagnostics

                                           iv.     STDS

                                             v.     Endemic diseases

                                           vi.     Norms

                                         vii.     High risk behaviors

c.    Predictions vs. Reality

                                              i.     Not matching up

                                            ii.     Worse than expected

d.    Strategies

                                              i.     ABC Model

                                            ii.     Prevention

1.    Barrier

                                          iii.     Treatment

                                           iv.     PEPFAR

1.    Goals

a.    Prevent 7 million infections

b.    ARV to 2 million

c.    Care for 10 million

2.    Funding

a.    39 Billion HIV

b.    4 Billion TB

c.    5 Billion malaria

3.    Wording allows conscience clause and sex worker clause

a.    Both neglect most at risk populations

                                             v.     Challenges

1.    Vertical Transmission

a.    In utero

b.    Labor

c.    Breast milk

d.    Guidelines

                                                                                                    i.     Breastfeeding still recommended

                                                                                                  ii.     Preventative therapy techniques not feasible

                                                                                                iii.     In developed countries, more possible

                                           vi.     HIV TB

1.    TB = leading cause of death

2.    1/3 HIV deaths

3.    14 million co infected

4.    Promotes TB disease

5.    Increased transmission to others

                                         vii.     Gender

1.    Many married with one partner

2.    Africa and the Carribean = highest prevalence

3.    Societal/cultural imbalance

4.    Immature reproductive tracts

5.    Menstruation

6.    Small tears in tissue

Week 6: HIV

I.              Origin

a.    Zoonotic

                                              i.     HIV-1

1.    Worldwide, highly virulent

                                            ii.     HIV-2

1.    West Africa, slower, less virulent

b.    Virus Type

                                              i.     Lentivirus

1.    Lenti=slow

                                            ii.     Retrovirus

1.    RNA-DNA

2.    Transcriptase

c.    1981

                                              i.     Discovered in US

                                            ii.     Kaposi’s Sarcoma

d.    1983

                                              i.     Discovery of HIV

                                            ii.     Credited to Luc Montagnier and Robert Gallo

II.            Transmission

a.    Possibilities

                                              i.     Sexual contact

                                            ii.     Blood on blood

                                          iii.     Tissue transplant

                                           iv.     IV sharing

                                             v.     Trans placental

                                           vi.     Accidental healthcare infection

b.    Infection aided by STDs

c.    CD4 T lymphocytes

III.         Structure and Replication

a.    GP 120 Attachment and entry

b.    P24 core antigen

IV.         Natural History

a.    Antigen presenting dendritic cells bind the virus

b.    Stages

                                              i.     Acute infection (flu like or mono symptoms)

                                            ii.     Strong cell mediated and humoral immune defense

                                          iii.     Clinical latency

                                           iv.     Loss of CD 4+ T4 cells

                                             v.     Other cell type migration

c.    High initial viral load phase=often missed

d.    AIDS

                                              i.     Profound immunosuppression

                                            ii.     High viral loads, low CD4 counts <200

                                          iii.     Presence of opportunistic infection

                                           iv.     Positive HIV test

                                             v.     Paradox: High viral load leads to low CD4, but spread by CD4

V.           Lab Testing

a.    First test= high sensitivity, many false positives

b.    Second test= High Specificity

c.    Rapid tests = important for walk in clinics

d.    Testing is done in newborn clinics