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How do you prove it?

how do you proove it

People often make assumptions about who infected them with HIV or a sexually transmitted infection (STI). This is usually based on the idea that the person who tested positive first was the person who was actually infected first.

This is not necessarily the case. Sometimes, the person who complains to the police after recently testing as HIV positive turns out to have infected the person they are accusing. So it is important to be sure before making any allegations.

Is it possible to prove who infected me?

It is possible that the person making the complaint (‘the complainant’) was infected either by the person they’re accusing or by someone else. They also might have been infected in another way (for example, when sharing drug injecting equipment or during a blood transfusion in a foreign country) months or even years before they met the person they are accusing.

With something like herpes, many people carry the virus without ever knowing it.

If your sexual history or testing history shows that you have had sex with a number of other partners, it is likely that they will all have to be eliminated as suspects before a case can proceed.

The police should make all these investigations before referring the case to prosecutors. The Crown Prosecution Service (CPS) for England and Wales will not bring a case where this work has not been done by police.

Can the police prove who infected me?

Complex scientific tests - known as 'phylogenetic analysis' - should always be done in HIV cases to compare the viruses of the complainant and the accused. If the two viruses are different, then this proves that there was no HIV transmission between the two people.

If the viruses appear to be similar it means that HIV transmission from the accused to the complainant could have taken place, but it does not prove it ‘beyond reasonable doubt’.

It is still possible that it was in fact the complainant who had transmitted HIV to the accused - or that both were infected by people sharing the same type of virus - or by the same person.

This is particularly likely in cases where people within the same social circles have all had sex with each other.

If you need help with matters concerning HIV transmission, call our free helpline THT Direct.

Next: Accused of HIV transmission ››

‹‹ Back to: When prosecutions fail



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The Information Standard: Certified member

This article was last reviewed on 16/9/2015 by Anna Peters

Date due for the next review: 16/9/2018

Content Author: Daisy Ellis

Current Owner: Policy

More information:

Policing Transmission, Terrence Higgins Trust & NAT (2008)

Intentional or Reckless Sexual Transmission of Infection by the Crown Prosecution Service

Policy for prosecuting cases involving the intentional or reckless sexual transmission of infection by the Crown Prosecution Service.