Concerted action on seroconversion to AIDS and death in Europe

Bringing together information on people with HIV to understand more about the disease and how people respond to treatment

What was this study about?

CASCADE was established in 1997 and is a collaboration between the investigators of 29 cohorts of persons with well-estimated dates of HIV seroconversion (seroconverters). CASCADE currently contains data from over 30,000 HIV-infected individuals, drawn from more than 300 clinics across Europe, Canada, and Australia as well as 13 sites in Sub-Saharan Africa.

The people who make up the CASCADE dataset are those who have had their HIV diagnosed early so have the best chances of access to treatment. These seroconverters therefore represent the ideal of what may be achieved through early testing and presentation, and set a gold standard against which to compare the outcome of all infected individuals.

CASCADE’s main aim is to monitor people who are newly infected with HIV and those already enrolled in studies, covering the entire duration of HIV infection. CASCADE currently brings together information:

  • in an anonymised form
  • from over 30,000 people who have HIV, and for whom we can be fairly sure of the date of infection or seroconversion.

By pooling information in this way, investigators in CASCADE are able to carry out research which would otherwise be difficult to do in small single studies.

Data from seroconverters are valuable in being able to relate events to the same time since an individual first became infected with HIV. Seroconverters thus provide a unique opportunity to study HIV throughout its whole infection period and also enable us to examine the characteristics of recently acquired HIV infection in the population over time.

What difference did this study make?

CASCADE has been able to provide important observational data on the course of HIV infection from the time of infection onwards. By pooling data, issues can be addressed that cannot be reliably addressed from single studies alone. This includes information on co-infections like hepatitis C and the impact on HIV outcomes, and how well the immune system recovers depending on what the levels were when antiretroviral therapy was started. As an example in 2017, the following publications were published by CASCADE:

Lack of decline in hepatitis C virus incidence among HIV-positive men who have sex with men during 1990-2014
van Santen DK, van der Helm JJ, Del Amo J, Meyer L, D'Arminio Monforte A, Price M, Béguelin CA, Zangerle R, Sannes M, Porter K, Geskus RB, Prins M; CASCADE Collaboration in EuroCoord.
J Hepatol. 2017 Aug;67(2):255-262.

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Predictors of CD4 cell recovery following initiation of antiretroviral therapy among HIV-1 positive patients with well-estimated dates of seroconversion
Stirrup OT, Copas AJ, Phillips AN, Gill MJ, Geskus RB, Touloumi G, Young J, Bucher HC, Babiker AG; CASCADE Collaboration in EuroCoord.
HIV Med. 2017 Dec 1.

View Publication


This study has moved to the Institute for Global Health.

Type of study

Observational study

Contact details

Who funded the study?

CASCADE is now part of the European Commission-funded EuroCoord (FP7)

When did it take place?

This is an ongoing project which began in 1997.

Where did it take place?

In 13 countries across Europe (including the UK), Australia, Canada, along with 13 clinics in Africa.

Who was included?

People with HIV who are cared for at a number of clinical centres throughout Europe, Canada, Australia, and Africa and who are enrolled in studies conducted by the institutions which are part of CASCADE are included. For all people included in these studies we can be fairly sure of the date of HIV seroconversion.