community control of STIs

Question 1

what is the May and Anderson HIV/STI transmission model

Answer 1

R=BCD

Question 2

what is R in the equation?

Answer 2

reproductive rate
the average number of new infections generated by each infected person
if this is less than 1, then the incidence decreases
if it is more than one then the incidence increases

Question 3

What is B in the eqn and what does it depend on?

Answer 3

infectivity rate:
the likelihood of transmission per sexual contact between an infected person and a susceptible partner
influenced by: behavioural factors eg condom use, type of sex eg anal as well as the microbiological characteristic of the organism

Question 4

What is C in the eqn

Answer 4

partner rate over time:
average number of new sexual partners formed over time between infected and susceptible people
this links to the NUMBER OF P=OPPORTUNITIES FOR TRANSMISSION

Question 5

what is D in the eqn?

Answer 5

duration of infection:

the average duration of infectiousness

Question 6

how is duration of infection reduced and what is it influenced by?

Answer 6

easy access to services
screening high risk poplns for asymptomatic individuals
influenced by health seeking behaviour and health awareness

Question 7

What is primary prevention in STI control?

Answer 7

reducing risk of acquiring STI in the first place

Question 8

What is secondary prevention in STI control?

Answer 8

case finding eg screening programmes - find and treat undetected cases of infection and removing these from the community pool

Question 9

What is tertiary prevention in STI control?

Answer 9

reducing morbidity/mortality

Question 10

What are examples of primary prevention strategies for STIs?

Answer 10

one to one risk reduction discussion - 15-20 min discussion in clinic, may need more than one, structured intervention based on motivational interviewing - for anyone at high risk of getting or transmitting an STI
keys, cash, condom campaign - public health campaigns
vaccination - for hep B and HPV
pre and post exposure prophylaxis and treatment as prevention U=U

Question 11

when is post-exposure prophylaxis used?

Answer 11

post sex
needle-stick injury
needs to be given within 72 hours
prevents HIV infection after the virus has entered the body

Question 12

what are the secondary prevention strategies for STIs?

Answer 12

easy access to STI/HIV tests and treatment eg national HIV testing week
partner notification
targeted screening:
• antenatal screening for HIV and syphilis
• national chlamydia screening programme
• HIV home testing - it starts with me

Question 13

what are the tertiary prevention strategies for HIV?

Answer 13

anti-retrovirals for HIV
prophylactic antibiotics for pneumocystis pneumonia
acyclovir for suppression of genital herpes

Question 14

what is partner notification?

Answer 14

a public health strategy that aims to CONTROL INFECTION by IDENTIFYING key individuals and sexual networks, WARN the unsuspecting and attempt to BREAK THE CHAIN of infection

Question 15

what are the aims of partner notification?

Answer 15

break the chain of transmission
prevent re-infection of the index pt
prevent complications of untreated infection

Question 16

How are partners traced?

Answer 16

pt referral - pt tells partner themselves
provider referral - hospital does contact tracing without mentioning the pt’s name or details
provider referral can be done by phone, text, letter and doesn’t contain the word STI
conditional or contract referral - when the pt initially tries to tell them and if this fails, the hospital will offer to help

Question 17

What can be done to manage PN if a pt tests positive in a non-specialist sexual health setting in sheffield?

Answer 17

can refer pt directly to sexual health sheffield where treatment and PN can be don automatically
or treat the pt in your speciality and then refer to SHS for PN
follow any referral pathways if any

Question 18

What are the challenges facing partner notification?

Answer 18

hard to reach group - phoneless, homeless, floor sleepers, social exclusion, criminal activities, health care low priority
getting their contact details
how to trace them
how to make testing accessible for them

Question 19

What are the different sectors that may be involved in partner notification?

Answer 19

public health
GUM
Drug and alcohol advisory service
infectious diseases 
virology
CCGs - clinical commissioning groups 
specialist community outreach nurses 
infectious diseases 
police 
housing agnecies
prison services