In 2004 the English Health Protection Agency estimated that there were about 16000 people living in the UK who were unaware that they were infected with HIV. Knowledge of the prevalence of undiagnosed infection had previously led to the introduction of an antenatal screening program. In 2001 and 2004 the English/Welsh and Scottish Sexual Health Strategies respectively set targets for an increase in HIV testing by genitourinary medicine clinics and other settings where sexually transmitted infections are commonly managed. One outcome of these targets has been a debate about how best to increase testing rates. When HIV tests first became available in 1985, there were no effective treatments and to have a test that came back positive was tantamount to a death sentence with an unknown length of time on death row. Some people alleged that they were tested against their will and there was even talk of charging phlebotomists with assault. It was therefore particularly important to gain informed consent for the test.
These days, with reasonably effective antiretrovirals and greatly improved life expectancy, there are very few disadvantages to having a test. Therefore a protracted counselling session before the test is usually unnecessary. However, it is always good practice to inform a patient what investigations you are doing, why you are doing them and what the test involves. This is true whether you are doing thyroid function testing, a chest X-ray or an HIV test. In all these cases, the information should be tailored to the individual with more time spent on those people at risk of getting bad news when they call in to get their results.
Many genitourinary medicine clinics are choosing to provide information about HIV and its diagnosis in the form of a leaflet. A typical leaflet covers:
- • What HIV and acquired immune deficiency syndrome (AIDS) are.
- • How you can catch HIV.
- • How you can avoid catching HIV.
- • The advantages of knowing whether you have HIV, i.e. better prognosis if diagnosed early when antiretrovirals can prevent AIDS and prevention of onward transmission to a fetus or sexual partner.
- • Disadvantages of knowing you have HIV. Very few — some difficulty getting business visas for some countries or emigrating to others, distress — could the patient cope at the present time?
- • What the test involves.
- • The ‘window period’ (the time taken to develop antibodies following infection).
- • How to obtain the result.
- • What will happen if the test is negative.
- • What will happen if the test is positive.
In genitourinary medicine clinics, the leaflet is often given to the patient on arrival. In other settings the leaflet can be given to the patient if the clinician feels that a test is indicated.
Having read the leaflet, the patient then sees the doctor or nurse. The clinician will establish that the patient has understood the leaflet. If they have not understood it, the information it contains should be reiterated.
During the consultation, the clinician should establish the patient’s risk of having HIV. This is done by taking a sexual and risk history. For the sexual history. A typical risk assessment might involve asking the following questions:
- • Have you ever had sex with someone who has HIV?
- • For men: Have you ever had sex with a man?
- • For women: Have you ever had sex with a bisexual man?
- • Have you ever injected drugs?
- • Have you ever had sex with someone who has injected drugs?
- • Have you ever had sex with someone from outside the UK? If the answer is yes it is important to find out where the partner was from, since having sex with a Belgian is clearly lower risk than having sex with a Botswanan. UNAIDS collates information on HIV prevalence in each country and produces a useful map.
- • Have you ever had a non-professional tattoo or piercing?
- • Have you ever had contact with the sex industry? i.e. paid or been paid for sex.
According to the answers to these questions, the clinician assesses the person’s risk. In the UK, the main risk factors are sex with someone who has HIV, sex between men and sex with someone from a country where HIV is common. Answering yes to one of these questions would indicate that the person is at increased risk.
If they are perceived to be at increased risk, they should be told so and additional discussion should ensue covering topics such as:
- • How will they cope with a positive result?
- • Who should they tell about a positive result?
- • Testing for other infections (sexually transmitted infections/hepatitides depending on risk group).
If perceived to be at low risk, they should be told so and proceed to testing.
Some clinics ask the patient to sign to say that they consent to have the test, although this is now uncommon.
Even with the increasing prevalence of HIV, most people working in primary care will only very rarely receive a positive result from the lab. This makes it all the more important to have a plan for how you will handle this eventuality. Many ‘positive’ results are actually false positives, so it is important not to tell the patient the bad news until you have learnt more about the result. The lab will usually ask for a further specimen for confirmation; this is particularly important if not all the components of the test were positive.
Will you refer the patient to your local genitourinary medicine clinic for the confirmatory test or will you do it yourself? If the confirmatory test is positive, do you have enough information to hand to perform post-test counselling? It is important to have at least thought this through before you offer the patient an HIV test.
With pretest leaflets and standardized risk assessments, HIV testing will become more routine in primary care. This is a good thing and is essential if the number of undiagnosed cases is to be reduced.