Controladores de élite en población pediátrica es el tema que tratará Vinicius Adriano Vieira, de la Universidad de Oxford, en la Mesa de Básica de este miércoles.
Regarding the topic of your paper at the GeSIDA 2019 Congress, what are the main advances regarding Elite control in pediatric populations?
Identifying the mere existence of children who can control viraemia is the main advance in the field, as they have been scarcely described previously. We estimate paediatric elite controllers at a prevalence lower than 0.1% of HIV-infected children, which is 5-10-fold lower than in adults. Earlier this year, we published a paper describing 12 of these individuals identified from different cohorts around the globe, and now we have the opportunity to study how these children are capable of spontaneously controlling viraemia. With 92% of the paediatric elite controllers that we identified being female, a strong sex bias exists in this group, and they differ in many aspects from their adult counterparts. Identifying genetic mediators and immunological mechanisms in these children can help us develop new therapeutic strategies, and understand how HIV remission can be achieved in children.
What are the main challenges in this field?
The elite controller phenotype is extremely rare in children and, currently, all HIV-infected children start treatment after diagnosis. Viraemia control in this population is only achieved after years of infection, which makes almost impossible to identify new individuals who would be a potential elite controller. The main challenge in studying this population is the limited clinical data and biological samples available.
Do you see that vertical transmission has a very residual presence in our field and we can almost talk about eradication?
The adoption of all recommended interventions can reduce the risk of transmission to a residual rate, and many countries have seen a large reduction of new infections in children in the past few years. We are now close to eliminating mother-to-child transmission in these countries, however, continuous effort is necessary to keep diagnosing HIV infection and initiating treatment early in pregnancy.
And in developing countries, where it’s still a big problem, what strategies do you consider necessary for vertical transmission control?
In sub-Saharan Africa, at least 300 newborns are infected every day and the main barrier to eliminating transmission is the high incidence of seroconversion during pregnancy or breast-feeding, which increases the risk of transmission. Social and cultural diversity across communities requires tailored prevention interventions to enable the inclusion of vulnerable populations, thus eliminating HIV transmission.
Without forgetting pediatric HIV, since it is the field where you develop a good part of your professional work, what other research do you consider most promising?
Anecdotal cases like the Mississippi child and, more recently, the South African child illustrate the possibility of remission in the paediatric population. There is a unique opportunity to start therapy in a very early stage of infection thereby interrupting the seeding and diversification of the viral reservoir, improving the chances of remission if treatment is interrupted. Early treatment might not be enough to achieve functional cure, but new therapeutic strategies like the infusion of broadly neutralising antibodies, has just started to be tested in research and promising results might be seen in the near future.