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test the safety and efficacy of this new formulation in young children

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Bringing antiretroviral drugs to children

The CHAPAS trials have ensured that many more children with HIV have benefited
from life-saving antiretrovirals.

The challenge

Most attention has been given to the spread of COVID-19 in urban settings, where social isolation and quarantining may be difficult, facilitating the spread of the SARS-CoV-2 virus. However, a significant proportion of the population of sub-Saharan Africa lives in rural areas, in which the spread of COVID-19 might show specific characteristics and require targeted control measures. Furthermore, frequent travel between urban and rural areas, for example for work, increases the risk that infections will be introduced into rural communities.

Health and demographic surveillance sites provide a ready-made platform for undertaking studies of COVID-19 transmission at household and community level in rural settings.

The COREP project is taking advantage of two health and demographic surveillance sites, in rural Kenya and South Africa, collectively covering a population of more than 200,000, in order to gather information on the disease burden and spread of COVID-19.

In Kenya, 500 households will be randomly selected and followed as a longitudinal cohort. Households will receive monthly visits from community health workers, who will screen for symptoms and collect finger-prick blood samples for antibody analysis. COVID-19 cases will be confirmed by molecular testing, and affected households will be intensively followed over the following month. This will provide complementary data on population-wide infection and localised transmission clusters.

The use of dried blood spot samples will also provide an opportunity to evaluate centralised antibody testing. Although requiring a transportation step, centralised antibody testing may be more reliable than point-of-care testing and offers the potential for high-throughput analyses that would greatly increase productivity and could be more cost-effective. Symptom screening and dried blood spot collection are also tasks that could be undertaken by community health workers, supporting efficient use of scarce healthcare human resources.

The project

The later CHAPAS-3 trial compared the efficacy and safety of three fixed-dose combinations including two without stavudine (found to have some long-term side effects in adults, leading to a recommendation that its use be discontinued in children). The trial the first of its kind in Africa studied nearly 500 children at four sites in two African countries.

The COREP project is working with populations in East and Southern Africa to generate data on the disease burden due to COVID-19 and transmission characteristics of SARS-CoV-2 in rural populations, including rates of asymptomatic infections, periods of transmissibility, and high-risk groups. The project will reveal whether rural areas should be prioritised, and how control measures might need to be adapted in such settings. It will also generate data on a ‘hub’ model of antibody response monitoring as a possible approach for tracking COVID-19 at the individual and population level.

ratios forfixed-dose combinations and on appropriatedosage according to weight. 

The CHAPAS-3 trial confirmed the effectiveness of fixed-dose combinations, providing further impetus to the rollout of antiretrovirals to children. Its evidence on abacavir informed the WHO recommendation of abacavir-containing combinations for first-line therapy in children. Trial data have also been used to support applications for regulatory approval for new scored efavirenz tablets.

Impact