L2 - global health AIDS Flashcards
Define Incidence
The number of new cases of a disease measured within a defined population within a specific time period
Define prevalence
The total number of cases of a disease in a defined population at a particular moment of time.
Define mortality rate
The incidence of death within a defined population within a specific time period
Reflect on the dramatic impact of emerging infectious diseases
With the emergence of HIV/AIDs, there were initially (1981) around 5 cases in young males from Pneumocystis pneumonia that couldn’t be explained, but which seemed to show an association due to demographic similarity. There were also some deaths. This then grew exponentially in the following months to 285 cases (March 1982) to 1.3 million people living with HIV in the US (2006).
What are the 5H’s
Homosexuals, Haitians, Haemophiliacs…
What were the risk factors of AID?
Injection drug use, male-to-male sexual contact, more sexual contacts, syphilis
How were hypotheses (drugs/infection) of AIDs risk factors tested?
75% of living cases were interviewed, no association with popper (inhaled nitrate drugs)
Define case-clustering
When all living cases are of a certain population sub-group and cases are all related to one another i.e. have many sexual partners in common
What is a case-control study
A study that sets out a known outcome and compares individuals with that outcome to those without. The study determines what connects the members of each group i.e. odds ratios.
How do you design a case-control study?
Retrospective.
Identify an outcome. Form a group of subjects with and without the outcome. Look back in time to identify exposures, compare the frequency of exposures in the case and control groups.
Among gay men engaging in homosexual activity, what other population sub-groups were affected by HIV?
- Injecting drug users
- Transfusion/Factor VIII recipients
What cases indicated that HIV was caused by an infection?
Monogamous sexual partners; babies transfused at birth; haemophiliacs
How did the amount of HIV positive test results change?
1978 <1%
1980 20%
Describe the distribution of HIV
90% in developing countries
What is the equation for frequency of a disease in the population?
number of cases in the population/number of people in the population
What was the number of people living with HIV in 2014?
36.9 million
What names of countries are most affected by HIV?
S. Africa, C. Africa, Russia, S. America
Describe prevalence of HIV from 1997-2006
Rapidly increasing up to around 1 100 000 (2006 level). Plateau in 1990s. Incidence roughly the same, although lower since 1991-2006.
Describe the global changes in HIV prevalence from 2007-2014
Total change from 2.7 to 2 million. Sub-Saharan Africa 1.9 million to 1.4 million. South and South-East Asia slight difference.
Describe 2016 HIV stats for UK
HIV diagnoses: 5000
AIDS + HIV diagnoses: 300
all-cause deaths in people with HIV: 500
Describe global birth proportions of newly diagnosed HIV cases in the UK
UK: 45% Rest of Europe: 17% Africa: 20% Asia: 7% The Americas: 10% Australasia: 2%
When was mother-to-child transmission of HIV and syphilis stopped in Cuba?
2015
How does incidence influence policy?
When the incidence nears 0, schools can be re-opened and outbreak can be declared over
State the equation for mortality rate
Deaths from disease in a given time period/population at the start of the time period
