South Africa is the epicentre of the HIV epidemic. The country has the highest number of people living with HIV globally. Around 7.8 million people live with HIV in South Africa. About 5.8 people million are on ARVs, 93% of which have an undetectable viral load. This  means that the amount of virus in their bodies is so low that it can’t be detected by tests. 

However, there is a group of people who have HIV, are not on treatment, yet the virus in their bodies is undetectable. This population is known as elite controllers. It’s estimated that for every 200 people living with HIV, around one may be an elite controller. This works out to around 0.5% of the global population of people living with HIV. 

Health-e News spoke with principal investigator of the HIV Host Genome project and senior lecturer at the University of KwaZulu Natal, Dr Veron Ramsuran, about the groundbreaking research the group is doing on the mechanism behind this protection.

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 What do we know about elite controllers?

When a person initially gets infected with HIV, they have a higher viral load. 

 Elite controllers are people who tested positive for the virus. However, after some time without treatment, their viral load is undetectable. We do regular follow ups and if a person’s viral load remains undetectable for a period of one to two years then we know they are elite controlled because they are controlling their viral load.

In South Africa, with its high rate of HIV infection, the prevalence of elite controllers also appears to be higher.

How is the virus controlled in elite controllers?

My research has been trying to identify what gives the ‘elite controllers’  the special ability to control the virus. 

There are multiple factors that can contribute toward that control. 

One of the factors is looking at the virus, so the virus itself may be defective in that individual. This could explain why a certain person is controlling it. 

Another factor could be the environment, for example, if the person eats good food, exercises, has a good diet and lives in a good environment. If the person doesn’t have any other comorbidities, they could be able to control the virus.

It was discovered that it’s the human genome of a particular individual that gives them  protection. 

The virus we have looked at in individuals who are elite controllers is very similar to the virus from people that are progressing with HIV. It is not the virus that is different, it’s more of the human genetics.

For how long is the virus suppressed?

The virus can be suppressed for more than 10 years. 

It varies from person to person. Elite controllers are protected from the  virus increasing to a level that is extremely high.  These individuals cannot transmit the virus to others including sexual partners. 

A person can still be pregnant and not transmit the virus to the foetus.

It is well established that people with an undetectable HI viral load cannot transmit the virus to others.  This is known as U= U.  People should be cautious and use protective measures to prevent other sexually transmitted infections.  

Explain your research around the human genome?

We have done whole genomic sequencing of these individuals (elite controllers). We tried to identify which genes are unique within them, how can they explain the protection found within them. 

We have identified new genes and new mutations that are present in individuals. Traditionally, there is a list of mutations or genes that are known to be associated with HIV. But this list is based largely on studies performed in the Western world. Our research is unique in that it looks at individuals of  African descent where the problem with HIV is at highest. According to the World Health Organisation, more than two-thirds of the people living with HIV worldwide, are in the African region.  

The HIV virus is different in different parts of the world. In South Africa you find sub C type which is an under studied virus and in the US is the sub type B which has been mostly researched about. 

How will the research impact the lives of Africans?

The most  important thing is that this research focuses on the right population, this will inform new treatment and new vaccine opportunities.

Our HIV research is adding to the general pool of knowledge pertaining to individuals of African descent, which will thereby inform new treatment and new vaccine opportunities.

This knowledge will be widely applicable and could have an impact on other diseases – infectious and non-infectious – as well as their drug interventions. It will make sure that Africans, just like everybody else, are at the centre of drug and vaccine development. – Health-e News