HIV Flashcards
What type of virus?
Human retrovirus
What cells does it infect?
Immune system cells and cause immunodeficiency
Characteristics
Genome, enveloped etc
2 copies of positive single-stranded RNA
Enveloped
What are the genotypes?
HIV-1
HIV-2
Briefly describe how HIV infects cell
- Attachment, entry, and uncoating
- Reverse transcription and integration
- Synthesis of viral parts
- Assemebly and release
Briefly describe the pathogenesis of untreated HIV
Primary infection -> Latency -> Progression to?
- Primary infection (weeks)
- Burst of viremia
- Transient decline in CD4 cells - Latency (years)
- Immune system fights off virus
- Chronic low level viremia - Progression to AIDs
- CD4 cell loss outweighs production (apoptosis, direct killing)
What are the clinical features of primary infection?
Fever, cough, cervical lymphadenopathy, maculopapular rash, rash on chest
What are the clinical features of latent infection?
Asymptomatic OR fever, malaise, loss of weight
How to screen and diagnose?
- PCR and culture: detect low levels of HIV DNA
- HIV antibody tests: ELISA
What is a confirmation test?
Western blot analysis
mandatory second test type
What are AIDs-defining conditions marked by?
- CD4+ cell count of less than 200 cells per ul of blood
- Apperance of 1 or more of the typical opportunistic infections or cancers
What are the clinical presentations of AIDs?
Oral thrush, cachexia, Kaposi’s sarcoma, Pneumocystis jiroveci pneumonia, Mycobacterium avium complex
How is it transmitted?
- Mother to child
- Sexual transmission
- IV Drug users
- Health care staff
What are some preventions?
- Advice to seropositive women
- Safer sexual practices
- Use of condoms
- Fewer partners
- Active treatment of other STDs
- Advice to stop injecting
- Do not share “works”
- Needle/syringe exchange programmes
- Advice on infection control
- Safe work practices
What is the route of transmission?
Rectal and vaginal mucosa
