Lecture 27: Sexually Transmitted Diseases Flashcards
Chlamydia in NZ
- Most common STI in 2014
- 629/100, 000 people (83% between 15 and 29)
- The has remained steadily prevalent (endemic in NZ)
- 83 infants reported
Ethnic Differences of chlaymydia
Europeans at the tops of the stats (healthcare access)
Gonorrhoea in NZ
- 70/100, 000 people
- 73% between 15-29
- 1 infant reported
- Bulk of disease in Europeans
It looks like female rates are going down in NZ for gonorrhoea, but if you look at specimen sites?
- High in urethral screening, less urine screening
- Rates of anorectal or throat screening have a slight bias towards males, and are increasing.
Whereas in females most testing is done from the vagina.
Drug resistance to Gonorrhea
Ciprafloxacin Resistance: recently become a massive issue in the early 2000’s (was already above the 5-10% cutoff for first-line treatment) and has changed the way we do treatment. Now over 50% resistances
Penicillin resistance: remained relatively stable.
Infectious Syphilis in NZ
Numbers have taken off in NZ, a significant outbreak predominantly in males (40+ years).
We can conclude from this that the spread is predominantly in older man-to-man encounters
Genital Warts in NZ
A decrease in the case counts of genital warts, genital herpes and NSU
- 5 year trend (2010-2014) showed a 36.8% decrease in the case counts of genital warts.
- The MAIN reason: women are vaccinating themselves
Why do we wan’t to know about sexual behaviour?
- To inform preventitive strategies
- To correct myths in public perceptions
- To fill gaps in knowledge (esp in asia and the middle east)/
What are the factors contributing to variations and trends in sexual behaviour.
- -Poverty
- Education
- Employment
- Demographic Trends: changing age structure of populations, trends towards later marriage
- Increased migration with and between countries
- Advances in contraception and access to a family-planning services
- Public Health HIV and STD prevention strategies*
What are the current trends and patterns towards sexual behaviour?
- Trends towards earlier sexual behavious (not as pronounced are you would think)
- Trend towards later marriage → increase in the prevalence of premarital sex
- Married people have the most sex
- Monogomy the most dominant pattern
- Men report multiple partnerships more then women
- Sexual activity in young single people tends to be sporadic and more in industrialised countries. (men over-report and women under-report)
- Condom use is increasing but rates of use remain low in many developing countries.
- First sexual experiance often forced
- Married women find negotiation of safer sex hard.
- Very early sexual experiance within marriage can be coercice and traumatic
What key factors influence the incidence and distribution of STI’s
Where do we get most of our knowledge about the distribution and patterns of sexual behaviour
From population based research of broadly similar countries to NZ
Best research: from UK studies
Lifestyle is?
NOT random and relatively fixed over time. You are not entirely in control and are a product of your environment.
The Sexual Trichotomy
-
Sexual Orientation
- the gender(s) an individual is attracted to -
Sexual Identity
- How individuals self-identify
- how individuals publicly identify -
Sexual Behaviour
- Sexual plans and actions
Key findings within British Data (Natsal-3)
- Shows huge changes in behaviour (especially in women) in terms of acceptance of same-sex marriage and intolerance to non-exclusive marriage
- Increase in # sexual partners in women, as well as the number of same-sex partners (societal aspects and anonomous asking)
- STI’s distributed heterogenously
- Increasing intervals between 1st sexual intercourse, cohabitation and childbearing for women.
- Poor health associated with decreased sexual activity and satisfaction.
- Non-volitional sex is mainly an experiance of young age and is associated with a range of adverse outcomes
- Young sex is increasing
Those with poor health status don’t tend to be _______
Those with poor health status don’t tend to be as sexually active
What are the statistics involved in good sexual function
in both men and women ~50% have experianced one or more sexual difficulties. But it was less common for people to say that they were distressed about it
Non-volitional sex
1/10 women (median age 18)
1/71 men (median age 16)
Types of risk for STI transmission
What’s the difference between risk markers vs risk factors in terms of STI acquisition?
Risk Markers: tend to be indirectly causal, and just something broad about the person.
Risk Factors: Directly casual, close to the point of STI acquisition. (Risk reduction techniques very important here!)
What is the Equation of STI transmission Dynamics
Ro = ßcD
Ro = reproductive rate of infection
ß = efficiency of transmission of the infection
c = mean rate of partner change
D = duration of infectiousness
Ro
Ro > 1 the incidence of STI increases
Ro <1 the incidence decreases
Ro = 1 steady state (auckland chlaymydia)
What are ‘core groups’?
Small groups of individuals who can create an increase in an STI within a population through the passage of the infection from the core group through bridging group members into the wider population
Vary in size for each infection
The Sexual Networks
How the array of sexual contacts can be modelled.
- Different infections travel through different networks
- Network Transmission is specific both in time and in space and explains some apparent demographic differences in STI rates (eg; gonorrhea and chlamydia patients may not be in the same networks)
Control strategies
