Myths and facts: HIV

In the third of a new series exploring some common misconceptions about conditions seen in general practice, GP Dr Toni Hazell debunks some myths about HIV – and explains some less well known facts

Myths

1. Pre-test counselling is needed before an HIV test is requested

We don’t all remember the stigma present in the early days of HIV, when a negative HIV test could lead to you being refused life insurance. The wife of a man who contracted HIV from infected blood was sacked from her job, while his son was called ‘AIDS boy’ at school and not allowed to drink from the water fountain. It was only in 2010 that the United States fully lifted their ban on entry for people with HIV. In this context, particularly in the pre-treatment era, the decision to take an HIV test was complicated and counselling was essential.

HIV is now a treatable medical condition and it is always best for someone with HIV to know that they have it. There is no need for lengthy pre-test counselling. It is sufficient for the patient to know that the test is being done, about the window period if relevant, and how they will get the result.

2. HIV tests must be done at least 12 weeks after exposure, to avoid a false negative result.

The window period for HIV refers to the early weeks after diagnosis, where someone may have contracted HIV but not have high enough levels of the HIV antibody for a test to be positive.

This used to be 12 weeks but is now 45 days for fourth-generation HIV tests, used in UK clinics, which test for both the HIV antibody and antigen. Patients can therefore be reassured that if their exposure to HIV was more than 45 days ago, a test sent to a laboratory will not result in a false negative result. If the exposure was during the last 45 days, the test should be repeated after the 45 day interval has passed. For point-of-care tests, which give a result within minutes, the window period remains at 90 days. ]

The window period is most relevant if you suspect seroconversion, the symptoms that occur in the weeks following infection. These may be non-specific, including fever, sore throat, malaise, lymphadenopathy, oral or genital ulcers and maculopapular rash. Less common presentations include headache, cranial nerve palsies and meningitis.

3. The most likely group to have undiagnosed HIV are men who have sex with men (MSM)

Traditional wisdom is that groups who are at high risk for HIV include men who have sex with men, those newly arrived from a country with a high prevalence of HIV, sex workers and those with a history of injectable drug use.

This remains the case, but these cohorts are often seen by services offering regular testing, and may use pre-exposure prophylaxis to prevent infection (discussed later in this article), so their likelihood of having undiagnosed HIV is smaller than previously thought.

 In contrast, an October 2023 report on HIV in England found that heterosexual women are more likely to refuse an HIV test and more likely to have had an HIV diagnosis delayed by the COVID-19 pandemic. Compared to one year earlier, there was a 31% rise in new diagnoses for heterosexual women living outside London (compared to 11% when heterosexual men and women are considered as one group), and women were more likely than men to be diagnosed at a late stage.  

It is estimated that 4,400 people in England have undiagnosed HIV (4% of the total population with HIV) and 1,500 of these are thought to be heterosexual women, compared to 1,500 MSM and 1,100 heterosexual men. The UK Health Security Agency says there is an urgent need to improve uptake of HIV testing in women.

NICE recommends that in areas with a high prevalence of HIV, an HIV test is offered on registration with a new GP and at any time that bloods are being done for another reason, if there has not been an HIV test in the last year. If prevalence is extremely high, we should consider offering testing at every contact. The website HIV-lens can be used to check if the prevalence of HIV in your area is high or extremely high, defined as 2 – 5 or ≥5 cases respectively per 1,000 people aged 15 – 59.

4. Women with HIV should not use an intrauterine device for contraception, due to the risk of pelvic infection

HIV itself does not significantly reduce contraception options, with the only strong relative contraindication being for the new insertion of an intrauterine device if the CD4 count is less than 200 cells/mm³. Many antiretroviral drugs are however enzyme inducing and this reduces contraceptive choice, with the depot injection or an intra-uterine device being the only reliable methods. Barrier methods are unaffected by drug interactions, but with a typical failure rate of 18% for male condoms, they are not usually recommended as a sole method of contraception. Antiretrovirals should always be recorded on the medication screen as a hospital issue, so that interactions will be picked up.

5. HIV always brings a reduced life expectancy

A patient with HIV who is engaged in care and on treatment can expect to have a normal life expectancy [citation] – those who are aged over 50 now make up more than 50% of the population living with HIV. This cohort does however have more co-morbidities, which they experience at a younger age. It is also possible that those with HIV are more likely to have frailty than the general population.

We may therefore have to adjust our usual thresholds for considering co-morbidities at any given age, when the patient in front of us has HIV. Risk factors for frailty include delayed initiation of antiretrovirals and the toxic effects of early antiretroviral regimes, which include alterations in lipid metabolism and irreversible peripheral neuropathy.

Facts

1. If someone with HIV has an undetectable viral load on treatment, they cannot pass it to a sexual partner

A person with HIV who has been on antiretrovirals for six months, with good adherence, and who has an undetectable viral load, cannot pass HIV to their sexual partner. In the PARTNER and PARTNER2 studies, well over 100,000 episodes of condomless sex in discordant couples were reviewed, with zero transmission. The British HIV Association endorsed U=U (Undetectable = Untransmittable) in 2017 [citation] and the Terrence Higgins Trust has for several years run an information campaign called Can’t Pass It On.

U=U means that discordant couples no longer need medical help to conceive and that people with HIV who are dating can choose when to disclose their HIV status, rather than risking a criminal charge if they don’t disclose before intercourse with a new partner. It is hoped that more widespread knowledge of U=U will help to reduce stigma. In South Africa, survey data has shown an inverse association between knowledge about U=U and stigmatising statements such as that teachers with HIV should not be employed in schools.

From the perspective of primary care, the prospect of a zero risk of transmission may be useful in discussions with a patient who is not engaging with HIV care or has poor adherence to their antiretrovirals. Information about U=U is also associated with a higher acceptance of HIV testing, according to a study in South Africa.

2. Women with HIV are always advised not to breastfeed

A logical extension of U=U would be that women who have an undetectable viral load on treatment can safely breastfeed, but unfortunately a small risk of transmission remains, and so it is still safest for all women with HIV living in the UK to formula feed. In many areas, formula is provided for free to this cohort, and their HIV consultant may offer cabergoline to suppress breast milk production.

However, some women may choose to breastfeed, for reasons such as the stigma of not breastfeeding in their community; one survey found that 66% felt pressured to invent a reason as to why they were not breastfeeding. HIV clinics will support women who choose to breastfeed, as long as they are closely supervised. Regimes include monthly viral load testing, breastfeeding only up to the age of six months, breastfeeding exclusively rather than mixed feeding, and temporarily switching to formula if mother or baby has gastroenteritis or there is any cracking or bleeding of the nipples.

Breastfeeding without engagement with an HIV clinic, or against medical advice, could be considered to be a child protection issue, as would be the case for non-engagement with any other means to prevent vertical transmission once the baby is born, such as refusing HIV testing of the baby or refusing to give the baby prophylactic antiretrovirals. If in doubt, talk to your local child protection team.

3. Women with HIV need annual cervical cancer screening until the age of 65

Women with HIV are at a higher risk of cervical cancer than the general population. They should have colposcopy at diagnosis, arranged by their consultant, and annual cervical screening from 25 until the screening programme ends at the age of 65, arranged by their GP. The practicalities of this depend on whether your cervical screening form has a box to tick to indicate that the woman has HIV. If it does, they will be recalled automatically – if not, you may need to run your own recall system for this cohort.

4. Some of your patients may be taking regular medication to prevent them from catching HIV

Some doctors will have taken post-exposure prophylaxis (PEP) after a needlestick accident – this is also available for sexual exposure (PEPSE), although in the era of U=U, the indications for PEPSE are much narrower than they once were. If approached by a patient wanting PEPSE, this can be arranged at a sexual and reproductive health clinic if open, or via the emergency department. It is an urgent matter, with the failure rate increasing with time between exposure and the first tablet being taken.

More recent in the UK is the availability of pre-exposure prophylaxis (PrEP), whereby someone who does not have HIV, but is at risk of acquiring it, takes a tablet to reduce this risk. PrEP is not currently prescribed in primary care, so if a patient asks for it then they should be directed to a local sexual and reproductive health clinic, where it may be offered as part of a risk-reduction package, which will include regular testing. As with other antiretrovirals, it should be recorded on the medication screen as hospital issue. The number needed to treat (NNT) with PrEP to avoid one case of HIV transmission is 62 – this compares favourably with other things that we do in primary care, such as statins for primary prevention where the NNT to prevent one stroke is 155.

5. Women with HIV can be given hormone replacement therapy (HRT) in primary care

In 2016, women of menopausal age accounted for nearly half of all women living with HIV in the UK. This cohort have a high rate of menopausal symptoms, but a very low uptake of HRT (8% in 2018, compared with a general population uptake at that time of 60%). The PRIME study found that 96% of GPs felt confident in managing the menopause, but that this fell to 46% if the woman has HIV. Reasons given included concern that symptoms attributed to the menopause might in fact be due to HIV related pathology, drug interactions and risks of HRT in women with HIV.

In general, women with HIV can have HRT on the same basis as women without HIV, although if they use enzyme-inducing antiretrovirals then a higher dose may be needed. If in doubt then speak to the woman’s consultant, but make sure that she is not left going back and forwards between her consultant and GP, with neither being willing to prescribe.