By IAN SCOONES, STEPS Centre Co-Director
More than 150 deaths in Mexico, a public emergency declared in the US, China banning imports of pigs from the USA and Mexico, health authorities across Asia and the Pacific on red alert, stock market prices for agriculture and travel industries down, while pharmaceutical stocks rise. These are just some of the symptoms of a rising wave of swine flu panic sweeping its way around the world.
As flu experts attempt to make sense of the emerging information about the threat from a new A/H1N1 influenza strain, the response from the top is unequivocally hard-hitting. US President Barack Obama has ordered a "very active, aggressive, and coordinated response,” according to White House homeland security advisor John Brennan. Meanwhile, with 20 confirmed cases of swine flu in the US, the country has procured seven million treatment courses of Tamiflu.
But will an “active, aggressive, and coordinated response” work? Recent disease events and threats, including swine flu, SARS, avian and human influenza and haemorrhagic fevers, have brought epidemics to global attention as never before. But how to address them has become a major challenge for twenty-first century health policy.
The increasing risk from newly-emerging diseases, and particularly those with the potential to become pandemic, is the result of a complex combination of social, ecological, environmental and economic factors. These include shifts in land use and migration, changes in livelihoods and food systems, climate change and increasing global travel and urbanisation. Most experts agree that a pandemic is almost inevitable at some point – and this will most likely be the result of transmission from animals. A global influenza pandemic could, under worst case scenarios, result in massive mortalities and huge economic disruption.
Following the avian influenza outbreaks of the past few years, much effort has been expended on devising pandemic preparedness and contingency plans, as well as improving surveillance and response systems and, in some places, stockpiling drugs and vaccines. But is the world prepared for a pandemic? Do we have effective global disease surveillance and control systems that can prevent a disaster?
The organisational landscape of global health has become increasingly complex. Debates continue over which organisations are in control of global health policy. Issues of national security and sovereignty, coordination, integration and harmonisation have accordingly come to the fore. The World Health Organisation’s revised International Health Regulations provide a global framework, but they rely on effective surveillance, timely reporting and the capacity to respond at all levels.
As the unfolding swine flu story is showing, once an outbreak is declared, international and national responses can swing into action quickly and effectively. So far the spread has been limited and mortality levels variable, although worryingly showing signs of a pandemic pattern. But what happens if the virus spreads? In pandemic situations, difficult trade-offs are presented between, for example, public health concerns, trade revenues, tourist movements and wider economic activity. These inevitably present major challenges for politicians and policymakers. Should the borders be closed? Should the army be called in to prevent movement? And who should decide? Such questions challenge global health governance arrangements to the full.
Identifying any new diseases early must of course be at the centre of any response to emerging infectious diseases. With most new human diseases emerging from animals, getting to grips with the social, economic and ecological drivers of disease emergence, before a deadly outbreak is essential. With increasingly intensified farming techniques and with humans and animals living in close proximity in dense urban settlements, for example, the potential for the emergence of new diseases is ever present.
No-one yet knows the back-story of the current swine flu outbreak. Mexican health officials do not seem to know how the virus emerged, when and from where. Genetic analysis shows an unusual mix of genes from North American and Eurasian pigs, birds and humans. A deeper analysis of the socio-ecological conditions for disease emergence and transmission is therefore essential, if lessons are to be learned. For the longer term, disease surveillance systems that move beyond disease-specific programmes towards integrated disease control systems are needed that look at human and animal diseases in tandem.
To understand the complex dynamic drivers of disease emergence and transmission thus requires solid epidemiological and medical information, but also insights from ecology, land use studies, socio-cultural and economic studies – and perhaps above all local knowledge and insights on changing disease environments. Perhaps pig farmers, meat processors and traders in Mexico know a lot about what has happened over the past months as the disease evolved and spread without detection and reporting. But we don’t know – indeed the virus has never even been isolated in pigs, so the origins remain obscure. Because of the slow reporting and confusion about the early spread in Mexico, the world has been taken by surprise as the virus quickly spread beyond any possibility of localised containment.
Right now, of course, the spotlight is focused on the international public health response. Margaret Chan, the director general of the WHO, has declared the swine flu outbreak a public health emergency of international concern, and governments around the world are gearing up for a full pandemic response – something which hopefully will not be needed. Keiji Fukuda, influenza chief at the WHO, argues that the world is now more prepared for a flu pandemic than it was when the last one struck. He is right, but in the complex, dynamic world of viral disease ecology, uncertainty and surprise are inevitable. Preparing for a pandemic means preparing for surprises – and being ready to respond rapidly and flexibly under conditions of uncertainty. As the experience with avian influenza has shown, this may require more than simply the top-down, “active and aggressive” technocratic response so often urged.
STEPS Centre work on epidemics
STEPS Centre research on avian influenza and pandemic preparedness
STEPS Working Paper, Health in a Dynamic World
What you need to know about swine flu from New Scientist
Tuesday, 28 April 2009
By IAN SCOONES, STEPS Centre Co-Director