GenLes - Using Viral Genetics to Curb the HIV Epidemic in Lesotho, South Africa

Major progress in curbing the HIV epidemic in Lesotho, Southern Africa has been achieved. However, there were still 11'000 new infections in 2019, emphasizing the importance of targeted prevention of new infections.

Within this project, the first aim is to combine phylogenetical tools and biological markers of infection recency to identify ongoing hotspots of HIV transmission in Lesotho. This project will use samples from the VIBRA trial ( to assess the possibility of micro-elimination within one district, inform local policy makers and could provide an innovative tool for other HIV programs in Southern Africa.

The second aim within this project is to tackle HIV drug resistance (HIVDR), which is a serious threat for the achievements made through the global roll-out of antiretroviral therapy (ART). In response to a worrying increase of pretreatment HIVDR in Southern Africa, the antiretroviral drug dolutegravir (DTG) is currently being rolled out for first-line treatment. However, first case reports of DTG resistance have been published, and information on DTG resistance and treatment outcomes in the context of non-B subtypes and infrequent viral load monitoring is scarce. Thus, we aim at using samples from the VITAL trial ( to longitudinally surveilling HIVDR during and up to two years after the large-scale roll-out of DTG in Lesotho, which may inform national and international clinical guidelines.

In summary, this project will use viral genetic analyses to improve targeted prevention and avoid treatment failure, thereby helping to curb the HIV epidemic in Lesotho.


Nadine Tschumi

Dr. Nadine Tschumi
Postdoctoral Scientific Collaborator

Project Facts