Lecture 29: Sexually Transmitted Diseases Flashcards
Why is information about sexual behaviour essential?
Inform preventative strategies
Correct myths public perceptions
Fill gaps in knowledge (esp. asia and middle east)
What are some factors contributing to sexual behaviours variations and trends?
poverty
education
employment (1. High employment = more money to pay for sex. 2. Low employment = compounded with low education)
demographic trends : changing age structure of populations; trends towards later marriages
migration (increase) b/w and within countries
globalisation of mass media
advances in contraception + access to family planning services
public health HIV and STD strategies (local campaigns)
What are some trends and patterns regarding sexual behaviour?
Earlier sexual experiences
Less pronounced and less widespread
Later marriage –> increased premarital sex (esp. in western)
Married people have to most sex
Monogomy dominant
Men have more partners than woman esp in developed countries
What are some factors which influence the incidence and distribution of STIs worldwide?
SES conditions (can go either way) Birth rate sexual behaviours cultural practices urbanisation (concurrent with sexual practices --> rapid spread) (increased opportunitey to meet a sexual partner) prostitution sex distribution (M:F) Self medication
Sexual activity in younger single people
sporadic
greater youth sexual activity in industrialised countries
- men over report, woman under report
Age mixing of age structures
greater age mixing in countries such as Africa
- older husband, younger wife
General sexual activity statistics
Condom use increasing, but low in developing countries (as prefer anal as contracpetive act)
Married woman find it harder to negotiate condom use/safe sex harder (family planning) vs single woman
first married sexual experience can be coercive and traumatic
Not all sex is consentiual
Population based research surrounding Sexual activity
population based research provides most of the information we know about patterns of sexual behaviour
Esp. BRITISH National survey of sexual attitudes and lifestyles (1990, 2000 and 2010) –> repeated 3x on a 10yearly basis –> provides robust data on population changes
Shows: average person is quite sexually conservative
Patterns of Living
socially conditioned culturally embedded economically constrained reflect personality have enduring consistency - you are a product of your social and cultural environment --> your patterns in which you live are not isolated acts and neither are they under autonomous self control - sexual lifestyle?
Sexual: The sexual trichotomy
- Sexual Orientation (gender attraction)
- Sexual Identity (internally self identify vs publicly identify)
- Sexual Behaviour (sexual plans proceeding actions)
Sexual Orientation/Identification
96.6% straight
1.6% gay/lesbian
0.7% bisexual
Note: KINSES data says that there is 6% gay in population, based on white, middle class, college students. Not population based
NATSAL UK sexual attitudes and lifestyle survey usages
- HIV prevalence and AIDS incidence
- Changes in behaviours over time
- Planning sexual health services and promotion strategies
- Improving STI epidemiology
NATSAL statistics changes is sexual lifestyles
Greater changes in woman sexual lifestyles in last 60 years
- same-sex acceptances + intolerance to non-exclusivity in marriage
STI distribution
heterogenously
Intervals in sexual growth
Woman: Increased time periods b/w First sexual intercourse –> cohabitation –> child bearing
Distribution of sexual function scores
increased variability in sexual function scores
- poor sexual function = -ve health outcomes
- poor health = decreased sexual activity = decreased satisfaction
Non-volition sex
- occurring increasingly at younger ages
- adverse outcomes
Change in average number of sexual partners
Men: 8.6 –> 12.6 –> 11.7
Woman: 3.7 –> 6.5 –> 7.7
- compared people in age group 16-44 in each 10 year test
Effect of health conditions on sexual life
1:6 people states that poor health conditions –> lead to an effect on their sexual life
- good health status = recent sexual acitivty/active
1/4 males and 1/5 Female sought appropriate health care
What percentage of population have had a same-sex experience?
Same sex experience:
M: 4% - 5% - 5%
F: 2% - 5% - 8%
Genital contact:
M: 6% - 8% - 10%
F: 4% - 10% - 16% (increasingly common in woman)
What is the percentage of the population that has sex prior to being 16?
Increased percentage of population has sex before 16
- change seen mainly in 16-24 age group
- less common in current older generation
- gender disparity (M:31% F:29%)
Number of sexual occasions in 4 weeks
Decreasing average 5 –> 3 sexual occasions in 4 weeks
Methods of sex with straight partners
Vaginal and Oral
- less anal sex - mainly done by experimental youth
Concern regarding sexual functional state (dryness, erection, anxious, interest)
Concern with sexual function: M: 42% F: 51%
- Worried about their sex life:
M:10% F:11%
- increasingly common in younger people, being concerned about their sexual function
Comparison b/w people who have had sex in the part year vs have had no sex in the past year
No sex in past year:
- DISATISFIED w. sex life
- DISTRESSED/ worried about sex life
- AVOIDED sex because of SEXUAL DIFFICULTIES
Comparative levels of sexual interest within relationships
1/4 couples have unequal sexual interest
Rate of experiencing sexual difficulties within relationships
1/5 couples have experienced sexual difficulties within their relationship
What are some types of risks for STI transmission?
- Risk markers (indirectly causal) - far away from STI acquisition
- Risk factors (directly causal)
- Risk modifiers
- sexual behaviour is the key determinant of incidence of viral STDs (incurable) e.g. viral HPV
- both sexual behaviour and healthcare behaviour are important determinants of BACTERIAL STDS (curable)
Risk Markers
NOT Controlled by the individual
- demographic factors
- causally linked to STI acquisition
- but probably only linked to sexual behaviour and/or disease prevalance
Risk factors
CAN be controlled by the individual
- directly related to the probability of aquiring an STI
- enhanced by risk Modiiers
Examples of Risk Markers
marital status
ethnicity
rural vs urban residence
SES
Examples of Risk markers and/or factors
age gender and gender identity smoking alcohol drug abuse other STIs lack of circumsician contraceptive method non-consenting sex
Risk Factors
- Sexual behaviours:
- number of partners
- rate of acquiring new partners
- partner free interval
- concurrency (how many partners at one time)
- casual partners
- gender preferences
- sexual practices - Health Care
- no use of barrier or microbicides
- late consultation for diagnosis, treatment
- non-referral of partners
- non-adherence to drug therapy
- douching
Non-referral of partners
Cycle of re-infection in intricate population: STI infections not treated –> renter population of people with similar background risk –> sex with someone who has had sex with an already infected person –> re-infected
STI transmission Dynamics
R0 = BcD R0 = reproductive rate of infection B = efficiency of transmission (of the infection) c = mean rate of partner change D = duration of infectiousness
Changes in reproductive rate of infection
R0 = BcD = Infection’s reproductive rate
R0 > 1 = increase in STIs (syphylis - spreading)
R0 < 1 = decrease in STIs
R0 =1 STEADY state (chlamydia- steady presence in NZ)
Reproductive rate of Infection in relation to gonorrhoea, chlamydia, syphillis and HIV
Table”
Core groups
- Small groups
- likely to be already infected individuals
- strongly interconnected
- can create an increase in STI within a population
- via infection passing from core group –> through BRIDGING group –> into wider population
Note: Core groups vary in size for population
Sexual Networks
sexual networks model the array of sexual Contacts
- different infections travel in different networks
- relates to core group or bridging population
transmission of STIs within sexual network is specific to both TIME and SPACE
- explains some demographic differences in STI rates
Sexual networks of gonnorhea and hclamydia
gonorrhoea patients and chlamydia patients may NOT be in the same sexual networks, =-> even through someone may be infected with both STI’s
What type of immunity does an already infected core group have?
Pr-emptive immunity
- cam recatch what you have already got
Density of sexual networks
Interconnections with people when include exploratory sexual activity
- bridging person
spreads a cluster of disease to another linear chain
Control strategies
importance of DHBS
if know DHB, tend to know what is generating their STI rates
Sexual function score
Decreased sexual function score = increased likelihood of reportion
- relationship breakup
- unhappy in relationship - difficult to talk about sex w. partner
- diagnosed with STI
- experience sex non-consentually/against their will
- paying for sex
- having more partners (woman only)
Chlamydia rates
higher chlamydia rates with increased number of sexual partners
Non-volitional sexual rates
lower than have been reported in other studies
M: 1:71 1.4%
F: 1:10 (9.8%)
Median occurrence of non-volition sex
M:16
F:18
- most likely that the person responsible is known (current or former partner)
Rates of unplanned pregnancy
Decreased overtime
