HIV in the era of undetectable

The gap between what is medically true about HIV and what most people believe is now wider than for almost any other condition, and the consequences of that gap fall on people living with it.

What changed

Effective antiretroviral therapy suppresses the virus to levels undetectable by standard tests, usually within months of starting treatment.

Multiple large studies following thousands of couples where one partner was undetectable and the other was not, across many thousands of acts of sex without condoms, recorded no transmissions attributable to the partner on treatment.

The conclusion, endorsed by health authorities internationally, is that an undetectable viral load means the virus cannot be transmitted sexually.

This is the meaning of the phrase undetectable equals untransmittable, and it is a statement of established evidence rather than an optimistic slogan.

What it means practically

A person diagnosed today, who starts treatment promptly and takes it, has a life expectancy approaching that of the general population.

They cannot pass the virus on to a sexual partner.

They can conceive and have children without transmission, and with appropriate care, transmission during pregnancy and birth is now very rare in settings with access to treatment.

Treatment is a daily tablet in most cases, and long-acting injectable options given every one or two months are now available in a number of countries.

Prevention for people without HIV

Pre-exposure prophylaxis is medication taken by an HIV-negative person that is highly effective at preventing acquisition — trials and real-world data show very high effectiveness when taken as prescribed.

It can be taken daily, or in an event-based regimen for some populations, and long-acting injectable forms exist.

Availability and cost vary enormously by country, from free through public services to expensive and difficult to access.

It does not protect against other infections, which is why regular screening is part of the programme.

Post-exposure prophylaxis is a course started after a possible exposure, ideally within hours and no later than seventy-two hours, and it is available through emergency and sexual health services.

Knowing that it exists before you need it is the point of mentioning it.

Testing

Fourth-generation laboratory tests detect most infections by around four to six weeks after exposure.

Rapid finger-prick and self-test kits are widely available and have somewhat longer window periods.

Late diagnosis remains the main driver of poor outcomes, and it is entirely a function of people not testing.

Routine opt-out testing in emergency departments and other settings has been introduced in several places precisely because targeted testing misses too many people.

Stigma, which is now the principal harm

Studies of people living with HIV consistently find that stigma affects mental health, disclosure, relationships and engagement with care more than the virus affects physical health.

Much of it rests on knowledge that was accurate in 1990 and has been wrong for a decade.

HIV is not transmitted by kissing, sharing utensils, toilets, swimming pools, insects or ordinary contact of any kind.

Criminalisation laws in many jurisdictions still reflect outdated science, and prosecutions have occurred in circumstances where transmission was impossible.

Correcting one's own beliefs is a small thing that materially affects other people's lives.

Living with it

The clinical picture in well-resourced settings has shifted from infection management to long-term health.

Attention now focuses on cardiovascular risk, bone density, kidney function, mental health and the interactions of ageing with long-term treatment.

Adherence remains the central requirement, since interruption allows the virus to rebound and can produce resistance.

And engagement with care is affected by everything social — housing, immigration status, poverty, stigma — which is why services that address those things achieve better clinical outcomes than those that only prescribe.

Disclosure

A subject with medical, legal and personal dimensions.

Legal obligations vary substantially by jurisdiction and are worth understanding accurately rather than assuming.

Clinically, an undetectable person poses no transmission risk, which changes the nature of the conversation entirely.

Support organisations exist specifically to help people think through when and how to tell partners, family and employers, and they are worth using rather than improvising.

What to take away

Test, because late diagnosis is the thing that still causes harm.

Know that prevention exists and is highly effective for people at ongoing risk.

And understand that a person on effective treatment cannot transmit the virus, which is the single fact that most needs to become common knowledge.

General information only, not medical advice. Availability of testing, PrEP and treatment varies by country — consult a sexual health service or qualified clinician.