Point-of-care devices for infant HIV diagnosis are effective and feasible in 8 African countries
Timely diagnosis of infants living with HIV in Africa remains a challenge, but new study shows point-of-care testing can work in the real world.
Point-of-care (POC) devices for testing infants for HIV can get HIV test results to caregivers more quickly than conventional early infant diagnosis (EID) strategies, finds an observational study across eight sub-Saharan countries (Cameroon, Côte d’Ivoire, Kenya, Lesotho, Mozambique, Rwanda, Swaziland, and Zimbabwe).
Over the 90-day observational period, average wait time was reduced from a 55-day average to same-day turnaround in most clinics. The proportion of test results returned within the 30-day window recommended by the World Health Organization (WHO), was even higher at 98.3%, compared to 18.9% of conventional test results.
With a timely diagnosis, infants can start antiretroviral treatment (ART) and greatly reduce their risk of morbidity and/or mortality. Without it, the authors note, an estimated 20% of infants will die before they reach two months, increasing to 35% by 12 months and 50% by two years.
Conventional EID testing in sub-Saharan Africa requires blood samples to be sent to laboratories with capacity to carry out nucleic acid testing. Clinics may often wait until they have several samples to send off at once, and results are returned either in paper form, or electronically. This process can take up to three months, which may include further lost time waiting for the caregiver to return for the results.
Point-of-care testing is a relatively new technology but has been put forward as an effective way to overcome challenges relating to EID. Two devices have been pre-qualified by the World Health Organization: m-PIMA and GeneXpert GX-IV. These are small, pin-prick operated devices that can be used in primary care settings by non-laboratory healthcare staff.
Both devices are also able to test for viral load, while GeneXpert can test for tuberculosis and other infectious diseases, so the potential for these devices as part of an integrated health system are significant.
Clinical and delivery data was retrospectively collected from 2,875 infants exposed to HIV and tested using conventional testing methods between March 3, 2014, and March 30, 2017. In December 2016, POC EID testing was introduced in eight sub-Saharan African countries as part of routine service delivery; data was collected as part of this study for 18,220 infants tested with POC testing.
Infants who tested positive with POC immediately started antiretroviral treatment while a second sample was sent to the lab for confirmation. As such, POC significantly increased the proportion of infants with HIV who were initiated on ART within 60 days of sample collection compared with conventional EID (92.3% vs 43.3%).
Seven of the countries successfully used a ‘hub-and-spoke’ model, where the POC tests were located in high volume centres called ‘hubs’, and periphery clinics, ‘spokes’, were clinics within an hour of the hubs that would send their samples for POC testing. This model requires a bit more funding for transport and communication, but these costs would be recuperated by not having as many POC devices in place.
The researchers found that this model did not compromise care for infants living with HIV. Most of the infants (72%) during the study period were tested at hub sites, and 99.4% of caregivers received test results within 30 days compared to 95.5% in spoke sites, and the average difference in turnaround time was just two days. Importantly, they found no significant difference in the amount of infants who started ART between hub and spoke sites.
They also found that the estimated cost per test result returned within 30 days was still lower than that of conventional testing. The authors noted, “In the future, POC EID costs could be decreased through expanded use of hub-and-spoke models or through integration of testing for HIV and other diseases, such as tuberculosis, on the same testing platform. As demand increases, manufacturers could offer decreased prices.”
This study offers a large sample size, broad range of countries included, use of non-laboratory staff to operate the POC EID platforms, and operation under real-world programmatic conditions – which suggest that POC EID is both feasible and effective.
In their conclusion, the authors note that strengthening conventional EID in Africa remains of critical importance, particularly for increasing lab capacity to manage other diseases. But POC devices have the potential to fill the critical time gap to get infants living with HIV on to ART as soon as possible.