STIs Flashcards
Define a sexually transmitted organism
A virus, bacteria, protozoan, insect or arthropod which can be spread by sexual contact
- Commensal
- Pathogen
What makes a sexually transmitted infection and disease?
STI is a pathogen that invades and multiples on the body and is transmissable by sexual contact. While also unlikely to be transmitted otherwise.
- Type 6 HPV STD is the disease caused by said STI
- Genital Warts
Why are STIs so important?
- They are unpleasant and can lead to death
- A huge drain on resources
- A massive psychosocial impact
- Very common
The number of STI diagnoses has increased over time, why do you think this is?
May be more cases, due to increase number of parteners, anal sex and MSM
May be more diagnoses but not more cases as public and medical awareness increases as well as better tests
What models do we use to map spread of STIs?
Cores and Assortative mixing
Chains and random mixing
How does assortative mixing work for mapping spread of STIs?
A subpopulation (“Core”) have sex with each other (similar to them) but not the wider community i.e. a minority ethnicity
Therefore you see a high prevalence amongst the core but without spreading to the wider community i.e. Hep C infections amongst HIV +VE MSM
How does random mixing work for mapping the spread of STIs?
A very big population e.g. hetero men and women
Chains of sexual partners form rather than a tangled core and you get a disease of low prevalalence but a very wide dissemination along “chains”.
What questions about sexual history are important when investigating a possible STI?
- Last Sexual Contact?
- Casual or regular partner?
- Nationality and gender of partner?
- Nature of sexual contact?
- Condom?
- Contraception?
How do we go about notifying patients partner’s of their possible STI?
Client referral (patient does the telling)
Provider notification (NHS tells the contacts)
What further testing should be offered if an STI diagnosis is reached?
- Most STIs are risk factors for HIV acquisition and transmission.
- If someone has one STI (i.e. chlamydia) they could have another (i.e. HIV)
What areas of health promotion should we educate STI patients on?
- Condoms prevent transmission of some STIs -
- I.e. HIV, chlamydia, gonorrhoea
- Condoms aren’t very good at preventing transmission of other STIs
- I.e. herpes and warts
- Oral sex carries risks too
- Not as great as vaginal or anal sex
- Fellatio more than cunnilingus
- Alcohol and other drugs
Define a sexually transmitted infection (STI)
An infection by a pathogenwhich is sexually transmissible and which is unlikely to be transmitted by non-sexual means
- Neisseriagonorrhoeae
- HPV type 6
Define a sexually transmitted disease (STD)
A disorder of structure or function caused by a sexually transmitted pathogen
- Pelvic inflammatory disease
- Genital warts
What are the three venereal diseases of the VD Act of 1916?
- Syphilis (Treponema pallidum pallidum)
- Gonorrhoea (Neisseria gonorhoeae)
- Chancroid (Haemophilus ducreyi)
Name three bacteria which are sexually transmitted organisms
- Chlamydia trachomatis
- Klebsiella granulomatis
- Mycoplasma genitalium
Name three viruses which are sexually transmitted organisms
- HSV
- HIV
- HPV
- Molluscum contagiosum virus
Name three parasites which are sexually transmitted organisms
- Pthirus pubis
- Sarcoptes scabei
- Trichomonas vaginalis
What are the two ways in which a sexually transmitted organism can cause an STD or STI and give examples?
Infection
- Mycoplasmahominis
- Ureaplasmaurealyticum
Colonisation
- Bacterial vaginosis
- Genital candidosis
Name four characteristics of STIs
- They’re transmissible
- Asymptomatic most of the time
- All manageable but not always curable
- Avoidable
What are the implications for a person with an STI?
- Partner notification
- So hard to eradicate from a population. Need to prevent.
- Treatment & prevention of complications
- Primary prevention - education
What are the different types of sexual contact?
From top to bottom decreasing chance of catching an infection:
- Group sex
- Anal sex
- Vaginal sex
- Oral sex
- Touching someone else’s genitals with your genitals
- Mutual masturbation
What infections can be transmitted through genital contact only?
- Pubic lice (Pthiruspubis)
- Scabies (Sarcoptesscabeii)
- Warts (human papillomavirus types 6 &11)
- Herpes (Herpes Simplex Virus types 1 & 2)
What infections can be trasmitted through group sex?
Hepatitis C
Why are STIs important?
They cause morbidity and they can kill.
- Unpleasant symptoms
- Psychological distress
They’re a drain on resources.
- Managing infertility due to chlamydia: cost of IVF.
- Cost of HIV medication/ management of HIV related health conditions
- Taking time off work to get your warts frozen.
They’re common
- More than 1M new STIs acquired every day.
- More than 500M people have genital herpes
