A cafeteria approach to Covid testing

Different testing methods suited to contexts and peoples’ needs backed by robust data collection could help present an accurate representation of the spread, identify potential outbreak regions, enhance public health surveillance of public places, and enable greater stimulation of economic activity

Written by JVR Prasada Rao and Manisha Bhinge

The second wave of the Covid-19 pandemic pummelled India and stretched the healthcare infrastructure to its limits. India recorded over 414,280 cases of new infections on May 6 – the highest single-day surge since the onset of the pandemic. The even more distressing aspect of the second wave is that, unlike the first wave, the virus penetrated the remote corners of rural India. Owing to limited health care infrastructure and systemic deficiencies, the rural centres continue to be hit badly. The vaccination programme and other established containment measures need to be pursued aggressively to manage this situation.

For India, rapidly vaccinating a critical mass of the population in the next few months is a formidable challenge. Until then, containment measures such as testing, contact tracing, and genome surveillance need to be strengthened and leveraged using novel, context-specific strategies. The accelerated pace of innovation across the therapeutics and diagnostics landscape has laid the groundwork to refine the existing strategy. Even with the availability of multiple test diagnostic pathways, testing measures can be further tailored to serve specific contexts in the interest of equity and scalability.

India’s testing capacities have evolved as the virus began to be understood. With a 430-fold increase in the daily samples tested between early April 2020 and late May 2021, India’s testing volume expansion is one of the highest in the world. Unparalleled scientific collaboration, an extensive network of diagnostic laboratories, proactive private sector participation, and the deployment of different types of tests can be credited for this growth.

There are 2,590 government and private laboratories approved to carry out tests ranging from RT-PCR, TrueNat, and CBNAAT to RT-LAMP and CRISPR-Cas9 tests. This is a significant expansion considering the limitations that the country has had to weather, but it is by no measure sufficient.

The onslaught of infections in the second wave and the rapid rise in testing demand is a reminder that innovations must pivot the pandemic response. ICMR’s recent guidance relaxing the regulatory conditions for innovative testing solutions to allow sample collection methods from saliva, mouth rinse, gargle, blood, and serum sample is a welcome development. These new testing technologies will pave the way for a cafeteria approach and enhance the availability of testing kits. Giving impetus to these new tests and robust sequencing capacities is critical as new and deadlier mutations of the virus emerge across the world.

The cafeteria approach – a strategy employed for family planning programmes – entails developing various options and allowing people to choose based on their need. In a report by The Rockefeller Foundation, “The Road Ahead for Smart Covid-19 Testing and Tracing in India”, experts recommend this approach for Covid-19 testing. This can be achieved by developing a diverse portfolio of testing methods with guidance on suitability to different contexts and people’s needs. Adopting this model will enable public health decision-makers to cater to the deeply diverse settings in India.

Currently, tests like RT-PCR, TruNat, and CBNAAT continue to be the first choice tests for confirmatory diagnosis. Alongside this, there are a host of RAT tests that can be deployed for surveillance purposes, with sero-surveys complementing those efforts. Additionally, in resource-constrained areas lacking adequate RT-PCR facilities, multiple RAT tests can be used to confirm a SARS-CoV-2 infection.

However, even beyond confirmatory diagnosis and surveillance, testing stands to serve diverse purposes, especially for re-opening the economy. For instance, saliva-based RAT kits are reportedly quicker, more economical, and as accurate as RT-PCR. Yet, all 103 ICMR-validated antigen-based rapid kits rely exclusively on pharyngeal and nasal swabs.

Similarly, the introduction of lateral flow antigen tests, a simple self-testing solution for asymptomatic persons that can be undertaken at home, can transform the testing system. It can meet multiple goals — affording convenience to populations, taking the strain off of overwhelmed laboratories, and addressing the growing testing backlog crisis.

Targeted antibody testing in containment zones, prisons, vegetable markets, banks on CLIA based assays, can return 130 samples per hour, which could be a tremendous resource to inform policymakers of the scale of a potential outbreak. There is, thus, an urgent need to include these newer testing technologies in India’s testing and tracing strategy, in line with the technological advancements across the world.

As we grapple with the ongoing wave and prepare for the next one, it is imperative to check the spread of the infection by deploying a diverse portfolio of diagnostic tests. Even though the testing infrastructure has been massively scaled up over the last year, newer approaches are warranted given the colossal population of the country.

Adopting a cafeteria approach to Covid-19 testing backed by robust data collection could help present an accurate representation of the spread, identify potential outbreak regions, enhance public health surveillance of public places, and enable greater stimulation of economic activity. These strategic and smart testing measures will cement the objectives instituted by the country’s vaccination programme: protect populations for recovery and rebuilding.

Rao is the former Union Health Secretary and former UN Secretary General’s Special Envoy on HIV/AIDS. Bhinge is the Managing Director, Programmes, Health Initiative, The Rockefeller Foundation

Source: Read Full Article