Lecture 26: HIV/AIDS Flashcards
what is HIV/AIDS?
- Human immunodeficiency virus (HIV)
- RNA virus that infects immune cells
- If left untreated HIV progresses to Acquired Immune Deficiency Syndrome (AIDS)
is defined in 2 ways:
- CD4 count of <200 cells/mL3 blood
- Certain infections are AIDS defining illnesses e.g. candidiases of bronchi, trachea or lungs, invasive cervical cancer, chronic cryptopridiosis, karposi’s sarcoma
how is HIV transmitted?
- HIV is transmitted from person to person in four main ways
1. through anal and vaginal sex
2. through the sharing of contaminated injecting equipment (needles and syringes)
3. from an infected mother to her baby during pregnancy or childbirth or through breastfeeding
4. through transfusion of infected blood or blood components and the transplantation of infected tissue or organs
what are the three stages of infection for HIV?
Stage 1:
- Acute, 1-4 weeks after initial infection, may feel like flu-like symptoms
Stage 2:
- asymptomatic stage, can last 10-15 years
Stage 3: Symptomatic infection, immune system seriously damaged
how can HIV be suppressed?
HIV can be suppressed by combination antiretroviral therapy (ART) consisting of 3 or more antiretroviral drugs
ART does not cure HIV infection but suppresses viral replication within a person’s body and allows an individuals immune system to strengthen and regain the capacity to fight off infections
- WHO recommended that all people living with HIV be provided with life long ART
- A person libing with HIV who starts antiretroviral therapy today will have the same life expectancy as an HIV-negative person of the same age
what is the global burden of HIV/AIDS?
In 2020:
- ~38 million people living with HIV
- 20% don’t know their HIV statis
- 1-2million people become newly infected with HIV every year
- To date HIV has claimed 36million lives globally
- 680,000 died of AIDS-related illnesses in 2020
what is the global incidence and prevalence?
- Global HIV incidence, prevalence, mortality and people on ART, by sex, for all aged, 1980-2017
- there is a rising number of people who are living with HIV
- there are fewer notifications, increasing global ART coverage, fewer deaths
- prevalence drives incidnce
- initially in 1980, incidence increased, prevalence wasn’t moving because the proportion of incidence to mortality was very high
- prevalence increased as incidence increased after some time
- in the 1990s incidence decreased as we knew more about how to prevent it but prevalence went up because people with HIV weren’t dying anymore
- ART use has increased a lot since 2000s.
What countries are most affected by HIV/AIDS?
- the vast majority of people living with HIV are located in low and middle income countries. likely due to less effective prevention and less access to treatment
- estimted 68% of people living with HIV are living is sub-saharan africa
what populations are most affected by HIV?
- 6% sex workers
- 12% people who inject drugs
- 17% men who have sex with men
- 1% transgender women
- 18% clients of sex workers and sex partners of other key populations
- 46% remaining population
how does AIDS affect young people and women and girls?
Young people
- AIDS is the leading cause of death among young people (aged 10-24) in Africa, and second leading cause globally
Women and girls
- Women account for more than half the number people living with HIV worldwide
- Young women are twice as likely to acquire HIV as young men
how can the HIV epidemic be addressed?
- Surveillance of HIV is essential for monitoring epidemic trends and evaluating the effectiveness of a country’s response
- reducing HIV incidence means addressing the drivers of the HIV epidemic
what is a not-so efficient HIV prevention?
- promoting abstinence is not useful
- promoting condom use was useful though. the gay community got involved with promoting condom use
what is combination prevention?
- simultaneous use of complementary behavioural, biomedical and structural prevention strategies
- need to know the nature of the pandemic:
- generalised or concentrated epidemics, most common mode of transmission, key affected individuals and key epidemiological trends (incidence patterns)
- tailor responses to the needs to the epidemic
What is an example of combination prevention?
Behavioural:
- sex education
- consistent and correct condom use
- delay sexual debut
- reduce multiple partnerships
- treatment adherence
- reduce stigma and discrimination
- cash transfers
Biomedical:
- condoms
- male circumcision
- needle exchanges
- PMTCT (mother to child)
- treatment as prevention
- pre-exposure prophylaxis (PrEP)
- Testing
Structural:
- decriminalise homosexuality, sex work and drug use
- address gender inequalities (e.g. increase access to education)
- remove barriers to accessing sexual health services (e.g. no parental consent required)
how can policy, legal and social environments affect HIV?
- structural drivers at macro-level influence patterns of behaviour and individual capacities
e. g.
- gender inequalities
- criminalisation of homosexuality or sex work
- stigma
- Tackling the structural drivres of HIV
what is the 90-90-90 treatment for all initiative?
goals:
By 2020:
- 30 million people on treatment by 2020
- 90% of people living with HIV know their status
- 90% of people who know their HIV positive status are on antiretroviral therapy
- 90% of people on antiretroviral therapy are virally supressed
fully achieving the 90-90-90 targets translates into 73% of all people living with HIV being virally supressed
how have the HIV rates in New Zealand changed overtime
HIV is a notifiable disease in NZ, but remains anonymous
Case numbers were relatively stable until 2002.
Cases went up because before 2002 it was only new Zealanders who were diagnosed, but after 2002 people who were first diagnosed overseas were also included
Increase in heterosexual transmission due to increase in immigration to African countries
In 2010 is became harder for HIV positive people to immigrate to NZ. Drop in cases due to this.
With effective treatment who won’t get AIDS and need all the expensive treatment.
HIV community have a goal of eliminating transmission within NZ.
How have the rates of HIV for men who have sex with men changed since 1996?
This drop may be due to covid restrictions.
Being infected in new zealand has been dropping since 2016
Being infected ocerseas appears to be increasing slightly since 2016
how have the number of aids diagnoses and deaths changed since 1985?
Aids diagnosis in those who are notified with aids have dropped significantly since 1995
aids deaths have dropped more than diagnoses since 1995
once someone has aids, they are not as likely to die anymore.
