Over the past two decades, several high-impact pathogens have emerged or re-emerged. These include three new coronaviruses—namely, severe acute respiratory syndrome (SARS) in 2003; the Middle East respiratory syndrome (MERS) in 2012; and the current COVID-19 pandemic (SARS-CoV-2).
There are also several highly pathogenic influenza A viruses such as H5N1 in 2003; H1N1 pandemic in 2009; and the H7N9 in 2013. More recent pandemics include the Zika virus in 2016 and the continuing rise and spread of Ebola in West and Central Africa since 2013.
This trend of the increasing prevalence of pandemics is projected to continue, driven predominantly by urbanization, climate change, environmental degradation, and persistent social and economic inequality as well as the mass globalization of trade and travel. This is because the prevalence of pandemics has been catalyzed by the movement of pathogenic transmission among nonhuman animals to humans (zoonotic).
This is how we prevent the next pandemic
The current state of pandemic preparedness
Past epidemics which have shown pandemic potential were predominantly identified through unusual clusters of severe cases or deaths in populations. However, this form of identification is often missed by classic surveillance systems, which means identification is weak.
Screening of viruses has shown that approximately 1.7 million exist across 25 consequence viral families. Of these, 500,000-700,000 have a high probability of being zoonotic. In practice, even if the likelihood of spreading is low, the potential impact will be scaled, as illustrated by the COVID-19 pandemic. As such, this justifies investment in structures that can prevent pandemics.
Over the past decade, there have been global health security initiatives to expand existing capacities, processes, and institutional arrangements to prevent pandemics. These include the international health regulations on the global health security agenda; however, these have been insufficient in preventing, for example, the spread of SARS-CoV-2.
Following this recent viral pandemic, there is an unmet need to create global strategies, policies, and regulatory frameworks that adequately address all aspects of disease emergence.
These activities are collectively termed pandemic preparedness and consist of several core components: surveillance, to detect pathogens, data collection, and modeling to determine rate and means of spread, improvements in public health guidance and communication, and the development of safe and efficacious vaccines and therapies.
The world health organisation (WHO) pandemic preparedness and response
The WHO pandemic phases wait developed in 1999 and revised in 2005 these phrases have global appeal and provide a framework for countries across the world full pandemic preparedness and response planning.
The WHO define pandemic preparedness as a continuous process of planning, exercising, revising, and translating international, and sub-national pandemic preparedness and response plans. A pandemic plan is therefore a dynamic document that undergoes regular review and revisions were necessary based on outcomes and conclusions taken from outbreaks, epidemics, pandemics, or simulation exercises.
Pandemic preparedness was borne out of the international health regulations review committees declaration that globally, the response to severe influenza pandemic or any similarly global, sustained, and threatening public health emergency is insufficient.
Image Credit: anttoniart/Shutterstock.com
The current problems facing efforts to prevent pandemics
Despite the improvements made to prevent pandemics which have culminated in the WHO framework, and a drive towards a more coordinated global response, significant gaps and challenges exist in global pandemic preparedness. The International Health Regulations (IHR) compel all WHO member states to meet the standards for pandemic preparedness; however, progress towards meeting the IHR husband inconsistent, on several countries have not been able to meet basic requirements for compliance.
Since the establishment of the WHO framework, multiple outbreaks since then, namely the 2014 West Africa ebola epidemic, have revealed the gaps related to the rapid detection of the viral disease, availability and access ability of basic care facilities, tracing of contacts, quarantine, and isolation procedures. Moreover, it has exposed issues related to preparedness outside of the health sector, including lack of global coordination and the mobilization of response.
These gaps are exacerbated in resource-limited contexts and have posed catastrophic challenges during relatively localized epidemics – which demonstrate the potentially dire implications during fully-fledged global pandemics. This potential has been realized most recently in the COVID-19 pandemics.
How to prevent a pandemic
Surveillance systems are considered to be a mode of preventing pandemics. There are both current and historic examples of surveillance systems. For example, the global early warning and response system is a formalized means of monitoring and reporting outbreaks of disease which was established in 2006 by the World Health Organisation, the Food and Agriculture Organisation, and the world organization for animal health (OIE).
Partners across the world are therefore able to work in real-time, sharing information on local and national disease outbreaks as well as conducting a rapid cross-sectoral risk assessment. Collectively, they support the forecasting, prevention, and control of emerging diseases.
An example of existing surveillance is the WHO’s global influences surveillance on response system which has been evaluating and monitoring the evolution of influenza viruses, the information from which helps develop annual flu vaccines and served as a global alert mechanism for the emergence of new flu viruses that show the potential to cause a pandemic.
This surveillance response changed as a result of the 2009 H1N1 pandemic, which exposed the absence of information about the severity and impact of the disease was inadequate for mitigating the effects on public health. Therefore, most influenzas assistance across the globe incorporated standardized case definitions for influence illnesses.
Improving exist surveillance to prevent a pandemic
A global, risk-based, multifactorial viral surveillance network is hypothesized to be essential in detecting viral spillover before it becomes a local outbreak. This would preclude the need to carry out viral surveillance worldwide it would rely on strategic sampling in wild animals, humans, livestock, and known hotspot regions.
This proactive approach would mean that any viral diseases that threaten to spill over into human populations will be detected in real-time, and test samples so many viruses from a prioritized list of viral families would be conducted (i.e. those originating from wild animals).
In parallel with this, a global surveillance network protocol and support tool would be necessary to make sure that these viruses are in emanated before infecting humans. It is believed that this aim is possible owing to new discovery projects such as the global virome project and a large volume of metadata which how distributed are deposited in global databases.
These data could also contribute to improved diagnostic reagents and then use through a more widely available, cost-effective pathogen detection on sequencing devices.
Moreover, more advanced analytics, combined with bioinformatic tools and artificial intelligence, would enhance the capacity of a global surveillance system. This would require strong political commitment and unified governance as well as long-term financing. However, the effects of the COVID-19 pandemic have illustrated the devastating socio-economic, political, and health impacts of a pandemic which presents an opportunity to leverage political support to establish such global surveillance.
References:
- Carroll D, Morzaria S, Briand S, et al. (2021) Preventing the next pandemic: the power of a global viral surveillance network. BMJ. doi:10.1136/bmj.n485. PMID: 33712471.
- Maxmen A. (2021) Has COVID taught us anything about pandemic preparedness? Nature. doi:10.1038/d41586-021-02217-y.
Further Reading
Study reveals how COVID-19 affected the spread and evolution of seasonal influenza