Sunday 8 December 2019

Getting to Zero HIV

Getting to Zero HIV (and addressing other sexually transmitted infection epidemics)

Where did Getting to Zero HIV come from?
WHO / UNAIDS campaign since 2011 when it was beginning to be understood that effective treatment was a key tool for prevention

The latest UNAIDS 90:90:90 campaign aims to diagnose 90% of people with HIV, engage 90% into care to start HIV treatment and that 90% of patients become undetectable (i.e. uninfectious).  In a few countries this target has already been reached; however, find the remaining undiagnosed HIV positive individuals is an ongoing challenge

To achieve the first "90" - we need targeted testing and effective partner services to reduce the cost to make a diagnosis and ensure that we can get to zero HIV by 2030 with an emphasis on 'Fast-track cities'; however, each city has a limit to the resources that they can spend on this problem

When trying to work out the cost to diagnose a case of HIV a back of the envelope calculation is a useful exercise but it should be taken with a pinch of salt

The table below uses the following sources & assumptions:

  • The background incidence rate is key to doing these calculations from low incidence countries where it is 9/100,000 (England, PHE)  & 12/100,000 (CDC Atlas, Massachusetts) to some sub-Saharan countries where it is 100x times higher e.g. Eswatini 862/100,000 (UNAIDS HIV estimates)
  • The background rate will affect all the following estimates so I have focused on a country with low incidence
  • Testing in sexual health clinics has a 3/1000 diagnostic rate (18 months data from inner London clinic)
  • Outreach testing has three times the yield of 10/1000 (based on conversation with NAZ Latina)
  • The BASHH / BHIVA audit in 2018 on HIV partner services found that 18% of partners were infected whilst in countries where less patients are undetectable this number has been as high as 35% (20% was chosen as a representative figure)

Testing strategy
HIV diagnostic rate (#/1000)
Diagnostic cost to diagnose one case of HIV ($20/test)
Screening blood donors
Targeted testing in specific venues
x 25 less
Outreach & testing in ‘at risk’ communities
x 83 less
Testing sex partners of patient diagnosed with HIV
x  1666 less