Small viral load blips are not a problem

The aim of HIV treatment is to keep HIV viral load at the very low level known as ‘undetectable’. More precisely, 'undetectable' may be a level below 20 copies/ml or below 50 copies/ml. Whether it’s 20 or 50 will depend on which kind of test your clinic uses.

Some people taking HIV treatment experience temporary increases in their viral load that are called ‘blips’. Usually, the viral load then goes back down again.

For example, someone who previously had a viral load below 20 (in other words, ‘undetectable’) may have one viral load of 45. The next time viral load is tested, it is undetectable again.

Do viral load blips like this matter? Does a blip mean that your HIV treatment is more likely to stop working in the future?

A new Spanish study gives reassurance. It looked at over 4000 people who already had a stable undetectable viral load when they joined the study.

Around 800 people had a blip with a viral load between 20 and 50. The researchers found that these people were no more likely to have treatment failure later on. This shows that a viral load blip at this level is nothing to worry about.

For people with a blip between 50 and 200, the results were inconclusive. But people who had a blip above 200 were a little more likely to have a problem with their treatment later on.

Blips may have various causes, including laboratory errors, temporary changes in drug concentration, or temporary bursts of immune system activation – for example in response to having an infection like the flu.

Treatment success in Sweden

The United Nations and the World Health Organization have set targets for 90% of people with HIV to be diagnosed, 90% of diagnosed people to receive HIV treatment and 90% of people receiving treatment to have an undetectable viral load. These are known as the 90-90-90 targets. Scientists believe that if they are achieved, the spread of HIV will be brought under control.

Researchers in Sweden say that they are the first country to have achieved these targets: 90% of people with HIV have been diagnosed, 97% are linked to and retained in medical care, and 95% of those on treatment have a viral load below 50.

They say some of the reasons for this success include the small size of the country and its epidemic, free access to HIV treatment, support services, and good linkage of patients to specialist treatment centres.

Sweden also takes a more authoritarian approach than some other countries. People living with HIV are legally obliged to comply with their doctor’s instructions. This is in addition to the country having one of the worst track records in the world of imprisoning people who do not disclose their HIV status to sexual partners (even if they don’t pass HIV on).

Nonetheless, the UK and many other countries could learn from their success in making sure that people living with HIV have their condition diagnosed.