Introduction
Infectious disease epidemics and pandemics periodically threaten the health and livelihoods of people in wealthy and poor countries alike.1 2 Evidence suggests that the risk of emerging infectious diseases has increased over time due to intensification of international travel, trade and livestock husbandry, as well as increasing human population density and changing interactions between humans and wild animals.3 4 These drivers of disease emergence are likely to continue and intensify,2 and additional drivers of ecological change and disruption such as global warming are likely to further amplify disease emergence risk. Given the public health risk posed by epidemics and pandemics, it is critical to systematically assess global preparedness, and to identify regions that are not well equipped to respond to such threats to public health.
Despite significant investments in global health surveillance and capacity building, large parts of the world are unprepared to manage infectious disease threats. According to recent estimates drawing on the WHO-supported Joint External Evaluation (JEE) process, only a minority of countries for which data are available are fully compliant with the 2005 International Health Regulations (IHR), which require demonstrable capacity to mitigate public health risks.5 Such capacities matter greatly to human health. There is clear evidence that the scale and severity of the 2013–2016 West Africa Ebola epidemic was exacerbated by the weak state of health systems in West Africa, and in particular, limited local capacity for public health surveillance and outbreak response.6
National governments remain the primary actors and first line of defence in responding to high-priority infectious disease outbreaks. They are also the primary locus of capacity-building efforts aimed at improving preparedness. Improving global capacity to respond to infectious disease crises requires better data on national-level preparedness worldwide, in order to inform and calibrate both foreign and domestic investments in capacity.7 Existing frameworks for measuring preparedness, including WHO’s IHR Core Capacity Monitoring Framework and the JEE, have substantially improved our understanding of preparedness to mitigate global health threats, and have shed light on gaps in preparedness both by function and across geographies. However, these frameworks have two limitations. First, while both focus on public health competencies in great depth, they do not fully address the broader range of non-health system factors, including institutional, financial and infrastructural capacities, which are also fundamental building blocks for effective response to infectious disease epidemics. For example, the JEE includes an indicator for ‘Linking Public Health and Security Authorities’, which is important for assessing the coordination between these institutions. However, this indicator does not measure the capacity of the security authorities to perform their required functions. Given the importance of this and other enabling functions, metrics tracking these additional capacities should be incorporated into assessments of epidemic preparedness.
Second, the IHR consists primarily of self-reported data, which raises the potential for bias and inaccurate reporting. By contrast, the JEE includes a robust external peer review, but requires intensive and costly data collection and analytical efforts, limiting the speed and frequency with which it can be conducted, revised and updated. Without frequent updates, key changes in preparedness metrics might not be tracked in a timely manner, leading to potentially outdated information being used in decision-making for resource allocation.
Recent work to define metrics for comparative assessment of country-level preparedness has underscored the widely accepted need for effective tools in this space. The organisation ‘Prevent Epidemics’ has published to their website country-level assessments which draw exclusively on JEE data.8 Moore et al recently reported a disease vulnerability index that combines measures of intrinsic disease risk with measures of preparedness.9 Here we aim to measure country-level preparedness independent of intrinsic disease risk, in order to disentangle these two distinct drivers of risk and allow for their separate characterisation.
We address these gaps by developing a conceptual framework for the comparative measurement of epidemic preparedness and response capacity. We operationalise this framework through a global quantitative Epidemic Preparedness Index (EPI) measuring relative epidemic and pandemic preparedness across 188 countries.