Following precedents applied first in wealthy states, more than 140 countries have applied some form of lockdown restrictions to slow their COVID-19 epidemics. These measures have had an impact on slowing spread of the virus, but have often come at the cost of painful social and economic impacts. International agencies have warned that 49 million Africans may be pushed into extreme poverty, and a quarter of a billion people may face acute hunger. For health, this has already meant that routine services have been interrupted, meaning an estimated 13.5m children will miss vital vaccinations.
Lockdown strategies were adopted from wealthy countries. Sustainable exit strategies must be layered, feasible, community driven and context specific.
With lockdown measures proving difficult to sustain, many countries are now relaxing their lockdown measures; 58 of the 115 (50.4 percent) countries with remaining lockdown measures are imminently preparing to begin phasing them out. Wealthier countries have relaxed their policies first, utilising a four-layered strategy of social distancing, shielding of the vulnerable, contact tracing and public communication. Low-income countries, however, have material differences that change both the feasibility of these strategies and their cost-benefit calculus. In this blog we look at these four layers and assess their feasibility in low-income countries. We recommend that social distancing measures will need to be limited and carefully adapted, focusing on those that are sustainable for 6-12 months and strengthened with hygiene measures. Measures to shield the vulnerable needs to be community driven and piloted to test feasibility. Contact tracing must be adapted to be low cost and scalable, and public communications must focus on building trust with all communities.
Figure 1. COVID Stringency Heat Map - 29th June
Beyond lockdown—what are the objectives of COVID control strategies?
After lockdown, the main objective in most high-income countries (HICs) has been to use more sustainable tactics to maintain the reproduction number (R) at an “acceptable” level below 1 and thereby continue reducing the number of cases and deaths, whilst minimising impact on the economy and wider society. This posture will need to be sustained until a vaccine becomes widely available. A few HICs (notably Sweden and parts of the US) have allowed ongoing transmission of the virus, but sought to keep case numbers within health service capacity.
Low-income countries need to first consider the objective of their COVID strategies beyond lockdown. Given the challenge in implementing control measures, plus projections that without lockdowns COVID demands will exceed limited health system capacity in most low-income countries, the most viable scenario in many countries may be to slow the pace and severity of the epidemic, and manage the trade-offs with the economy and wider health service.
Beyond lockdown—adapting four layered strategies from HICs
High-income countries have used a layered combination of four strategies beyond lockdown: physical distancing measures (supplemented by hygiene measures), shielding the most vulnerable, contact tracing of cases and contacts, and public communication. But how feasible are these in low-income countries?
1) Physical distancing and mitigation, supplemented by hygiene measures
Distinct from lockdown tactics, but often applied in parallel, are more moderate physical distancing and mitigation practices, which, when combined with hygiene approaches, can contribute to slowing transmission. Emerging research suggests that individual transmissibility of SARS-COV-2 is highly variable, with as much as 80 percent of spread driven by as few as 10 percent of cases. This would mean that most infected people do not spread to others, and a large share of spread is dependent on “super-spreading” incidents in which one highly infectious individual infects many others. An emphasis on preventing these super-spreading opportunities—through bans on large gatherings, avoiding prolonged indoor group contact, and similar measures—has proven effective in limiting transmission in Japan without harsh lockdown tactics. Widespread mask-wearing—which has been widely adopted in many East Asian countries—is also increasingly believed to have a significant effect on limiting transmission. Finally, shifting to outdoor activities as much as possible will also reduce transmission risk significantly, as super-spreading incidents have occurred almost entirely in enclosed indoor settings.
Cost-benefit analysis in low-income countries
These measures (along with isolation measures, and infection control measures) should be widely feasible in low-income countries and would have a significant impact on transmission for as long as they are sustained. However, there is a high risk of a rebound in transmission if they are not maintained, which can quickly eliminate most of the benefits produced (as numerous US states are now finding). Some physical distancing measures have significant downsides, economically and socially, and a long-term impact on health. For example, school closures reduce the number of healthcare workers available to treat patients, and travel restrictions and bans on social gatherings can prevent vaccination campaigns (although masking and outdoor vaccinations may offset the risk). Market closures restrict food supplies, reduce income generation, and risk malnutrition. These measures can amplify the human impact of the epidemic, increasing the time it takes for the routine health service and the economy to get back to normal.
Countries need to carefully select the interventions, and should consider if they have capacity to mitigate the risks. They should weigh, for example, whether they have clear strategies to maintain essential health and nutrition services and vaccinations, and adequate plans to maintain incomes for the full duration required, including through direct cash transfers. The difficult trade-offs mean countries may want to focus on measures that reduce infection rates, are sustainable in the long term, and benefit the wider health sector, including scaling up water, sanitation, and hygiene measures.
2) Shield the vulnerable
Shielding the vulnerable aims specifically to reduce contact between the general population and the elderly and those with chronic underlying medical conditions. This has been a priority in most HICs, although often with minimal success.
Cost-benefit analysis in low-income countries
As far back as mid-March, researchers at LSHTM have demonstrated that there is a strong argument, a priori, that shielding should be a high priority for all low-income countries; for example, in Nigeria it could lead to a 43 percent reduction in deaths. This approach has fewer costs and downsides compared to the population-wide social distancing measures discussed above. In addition, it does not fundamentally alter the transmission dynamics, and so does not prevent herd immunity forming. Therefore, it is unlikely to cause a second rebound epidemic when it is lifted. It does, however, need to be sustained until herd immunity is reached to gain the maximum benefit, which may be more than 12 months.
The great unknown, however, is its feasibility. Is it realistic for Tanzania to isolate its estimated two million vulnerable people in so-called green zones? Countries need to consider if they have the capacity to support these people with food, water, electricity, income, and information, and critically, if they trust their own systems to deliver on it. Rather than re-creating disastrous “care homes” that have been so difficult to protect in wealthier countries, it is more likely that local communities will need to be supported to develop unique solutions that work for them and their social environment. This has not been done before, and implementation challenges mean it could do more harm than good. If countries have the capacity, this should be a high priority, and international agencies should provide the support required for pilot projects, the rapid dissemination of the results, and scaling up effective local solutions. Given the uncertainty about the viability of shielding strategies, these approaches should best be viewed as components of a wider strategy premised on distancing and tracing, rather than a strategic centerpiece in their own right.
3) Contact tracing and isolation
Test, test, test recommended the WHO on the 16th March. This was both to enable countries to follow the epidemics trends and to carry out contact tracing and isolation. Contact tracing and isolation is a core bedrock of traditional public health approaches to communicable disease control, and was used highly effectively in South Korea. Using seroprevalence information to estimate immunity, in conjunction with targeted PCR testing to estimate current case numbers can also inform, in a cost-effective way, the opening up of the economy.
Cost-benefit analysis in low-income countries
The major cost of contact tracing is the opportunity cost of diverting these staff away from other essential health areas such as community WASH education or vaccination. Experience from Ghana, Kenya, South Africa, and India has shown how hard it is to sustain a wide range testing strategy in resource constrained settings.
Scaling up the training of new community health workers, appropriately equipped with PPE, to support the COVID response, including contact tracing and implement WASH programmes and education, would therefore help reduce these trade-offs, and should be considered a no-regret policy, as they will be able to make major contributions to the health service post-COVID.
Large scale contact tracing and isolation in the low-income country context is feasible. Many countries already have the systems and a large number of community health workers who can facilitate this. Africa CDC has been working to increase the supply of tests, but where limited testing capacity is still a challenge, it can be supplemented with syndromic contact tracing approaches, where cases are identified by symptoms without needing to wait for tests. Indeed, the speed of syndromic contact tracing can make it more effective than test-based programmes, and protect limited test resources for higher priorities such as testing health care workers. In parallel, it will also be necessary to protect the contact tracing workers with PPE, and to provide food and livelihood support through, for instance, direct cash transfers to those who are isolated or quarantined. In parallel, testing can help with controlling nosocomial transmission and transmission in institutional settings such as prisons and care homes.
Contact tracing and isolation cannot, on its own, keep the R below 1; it will struggle to keep up when cases are growing exponentially. But as a complement to a sustainable distancing strategy and a transition step out of lockdowns, it can play an important role. Countries will have to pursue a step-wise approach, as recommended by the Africa CDC. Low-cost, scalable community-based syndromic contact tracing and isolation that is sustainable through the peak of the epidemic should be considered, particularly in the 32 African countries which already have community based surveillance built into their Integrated Disease Surveillance and Response (IDSR) systems.
4) Communication and public trust
As countries transition out of lockdown, they are also transitioning out of a phase in which measures are government imposed and into a phase in which containment measures must be community owned. Past outbreaks, notably the Ebola crisis in 2014, have demonstrated that community understanding, trust, and ownership of response efforts are vital to epidemic control. When people understand how the virus is spread, and what they need to do to protect themselves and their communities, they can begin applying those measures on their own initiative. A compelling example of this is the experience of the Dharavi informal settlement outside Mumbai, where community leaders conducted door-to-door symptomatic screening throughout the community, providing safe isolation in quarantine centres to symptomatic individuals. Authorities built trust in the process by providing food to quarantined individuals and adapting measures to accommodate for Ramadan practices. This community-based approach of chasing down the virus prevented a major outbreak in Dharavi despite the incredibly high population and household density in the slum.
As more countries move towards sustainable distancing strategies, this kind of proactive community engagement and trust-building will be crucial. Public compliance with outbreak control measures can only be sustained if community members are consulted, heard, and supported by public health authorities. Proactive, consistent outreach and communication about risk mitigation measures is essential. Equally essential is two-way feedback, so that authorities can adapt strategies to reflect public preferences and concerns. This kind of community-driven adaptation of tactics (such as changing the colour of burial shrouds used by safe burial teams during the Ebola outbreak) both improves public cooperation and builds overall trust in the response effort.
Countries need to be supported to deploy layered context-specific mitigation strategies after lockdown
Many low-income countries have employed variants of a lockdown strategy, but now the majority are finding this difficult to sustain and are planning their exit. Guidance on how to carry out a careful but rapid transition to different means of suppressing transmission is becoming urgent. It may not be possible for countries to fully contain transmission once lockdowns are lifted; R may remain higher than 1 and case numbers may continue to rise. But by applying a four-layered approach of non-lockdown social distancing and mitigation measures, shielding the vulnerable to the extent possible, contact tracing, and public communication, countries may be still able to do much to slow and reduce transmission, which will mitigate the total number of deaths.
We would like to acknowledge Cassandra Nemzoff and Sharif Ismail for valuable comments and advice on the blog.