Emerging Infection Diseases
Global Risks, Global Strategy
SARS. Ebola. Pandemic influenza. New diseases like these are emerging all the time. We don’t know when they are coming – but they are coming. Most of them first arise in low-income countries that are not well equipped to find and eliminate them. If the UK, the US and other high income countries want to avoid deaths and the cost of tackling novel diseases in the developed world, they could do worse than looking at ways to stop the spread of new diseases in countries in which they occur. An ounce of prevention is worth £££ of cure.
Humans and microbes are locked in an ever-escalating arms race. We develop complex immune system protection, but germs always seem to be able to find ways to avoid and even exploit our defences. Over human history of evolution, humans have largely been limited to relatively small geographical distances; 200 years ago most people never went more than 20 miles from their birthplace. This meant that diseases tended to move slowly and generally within a specific climate zone. Now, with globalisation and mass travel, disease migration patterns have altered radically. Combined with climate change, pathogens have spread far from the areas they started, and new ones are being discovered at the rate of about one per year. Emerging diseases pose significant threats to low, middle, and high-income countries. Most of the pathogens originate in developing countries, although many of these are not identified until they migrate to developed countries with more sophisticated labs. Developing ways of rapid identification, isolation, and treatment of emerging infectious diseases would benefit both developed and developing countries.
With globalisation and mass
travel, disease migration
patterns have altered radically.
Combined with climate change,
pathogens have spread far
from the areas they started
There have been several attempts to develop large-scale epidemiological networks, but these have largely been confined to high- and middle-income countries. This is partly a matter of pragmatism as these countries have more developed intra-national surveillance systems, which makes the collection and dissemination of information between countries much easier. The EU has recently developed its own international public health agency, the European Centre for Disease Control and Prevention (ECDC). As has been shown with the development of E. coli O104:H4, this type of international collaboration is crucial even between countries with large health budgets and many resources. When new epidemics are identified early, before the disease becomes entrenched in the population, there may even be the possibility of elimination, if not eradication.
Disease Surveillance: Not Just for Rich Countries
The best way to provide health care in resource-poor environments has been discussed at great length. The general consensus is that improving public health infrastructure is an important element in improving health in countries where money is limited. There have been arguments surrounding the strategy of disease elimination and eradication in low- and middle-income countries. One issue raised is whether this type of top-down health intervention, constructed and funded by the international community and high-income country donors, removes resources from more fundamental primary health care in low-income countries. There is an analogous situation with emerging infectious diseases; comprehensive surveillance is difficult to achieve, resource-intensive, and requires the development of communication systems. It seems to be a false dichotomy, however, as improving communication and surveillance is an important element of improving primary health care. Rather than being antagonistic, these functions are somewhat symbiotic, and provide benefits not only to the target country, but to other countries as well. These positive externalities are a crucial factor in garnering and maintaining political support within high-income donor countries.
The Spread of Chikungunya Virus
One important potential benefit for high-income countries supporting the infectious disease surveillance networks of low and middle income countries is early reporting. When emerging infectious diseases are allowed to spread in the region of origin, importation to other zones is likely, if not inevitable. As climate change has expanded the areas in which tropical insects and other disease vectors can thrive – this importation can lead to endogenous transmission within higher income countries. One example of this was the Chikungunya virus fever outbreak in Italy in 2007. Chikungunya virus fever is a vector-spread disease, mostly found in the Indian Ocean region.
It is usually spread by Aedes aegypti and Aedes albopictus mosquitoes, most commonly found in the tropical zone. There have been cases identified in other climate zones, but until recently, these were in people who had contracted the disease in an endemic zone, and then travelled to a colder region. In 2007, there was a large-scale outbreak in the Indian Ocean region, with 5003 confirmed cases (and likely many, many more). Shortly after this outbreak, several cases of Chikungunya fever were reported in Castiglione di Cervia, Italy1. It is unclear precisely where the outbreak originated, but it soon became known that the disease was spreading through the town via mosquitos: this was the first occurrence in Europe. The outbreak led to 334 suspected cases, with 204 confirmed in a laboratory. The reaction also showed the importance of international cooperation, as the newly formed ECDC coordinated the response to the outbreak. In reasonably short order, the reservoir of mosquitoes in the area had been eliminated, and the outbreak stopped.
Outbreak Responses and Inequity
Responses to emerging infections have not always been as orderly. The handling of the 2003 SARS outbreak provided a classic case study of multiple fundamental mistakes, and ways in which international collaboration can fail. The Chinese government was secretive and withheld crucial information that prolonged the period before effective international collaboration was possible2. The Canadian government used its influence to have the WHO rescind a travel restriction, and then permitted a second wave of infection to occur in order to minimise economic consequences3. In other ways, the international health machine worked extremely efficiently. The WHO reacted swiftly when the problem was brought to them, and effective quarantine measures were developed and implemented to a significant degree, if not perfectly.
After the SARS epidemic, emerging infectious diseases rose dramatically on the policy agenda, and interest in preventing global spread has prompted policymakers in high-income countries to look at surveillance in high-risk source countries. The risks perceived by high-income countries in the advent of an overwhelming pandemic like the 1918-19 influenza pandemic reached beyond health protection to national security. The divisions between high- and low-income countries were highlighted in the preparations for an H5N1 pandemic, and then the real H1N1-2009 variant pandemic. The inequitable distribution of resources between countries where new strains are likely to originate, and the countries which will develop and manufacture effective countermeasures such as vaccines has also been a cause for concern for many low- income countries.
Indonesia is the clearest example of where this inequity has had serious consequences. In 2007, Indonesia began restricting access to influenza samples, and the situation has been unstable ever since4. This has been extremely unpopular with the international health community. Indonesia has justified its position by stating that the current way that vaccine development is carried out and the price applied by manufacturers, would mean that Indonesia and its citizens would not be able to afford it. This stance has arisen in response to the treatment of low-income countries by the private sector. Indonesia wishes to avoid being in the position where access to the vaccine is at the whim of an international organisation that has limited responsibility to any state government. In order to do so, Indonesia has been prepared to use its restricted leverage. If high income countries wish to encourage Indonesia to cooperate with virus sample sharing, it will be necessary either to compel compliance (perhaps via sanctions), or to improve incentives (such as international aid). A complicating factor is the production of generic drugs within Indonesia, a practice deplored by the governments of high-income countries with large pharmaceutical companies who have patents to protect. These same companies control the production and pricing of any vaccine in the event of a pandemic, with reference to the WHO and national governments.
The SARS epidemic focused attention on emerging infectious diseases. During the SARS outbreak in China, there was under-reporting, misreporting, and very little data sharing until the global outbreak was well underway. There was a fear of a loss of face and of disrupted international trade and tourism, and so these protectionist strategies were employed to mitigate the worst of the economic effects. In order to avoid these evasion strategies in Indonesia and other low-income countries that may be host to future emerging infectious diseases, and to address the concerns of low- and middle-income countries about surveillance capacity and unequal resource allocation in the event of a pandemic, more direct assistance may be required. The creation of stable public health infrastructure, the sine qua non of the Right to Health movement, would simultaneously improve health and provide consistent epidemiological reporting that would benefit both low and high income countries. Global risks need global strategies.
Dr. Grace Jennings is a visiting Fellow at the London School of Hygiene and Tropical Medicine.
 Chan L. et al. (2010) China’s Engagement with Global Health Diplomacy: Was SARS a Watershed? PLoS Medicine. 7(4).
 Leslie M. (2006) Fear and Coughing in Toronto: SARS and the Uses of Risk. Canadian Journal of Communication. 31(2).
 Nuzzo J., Kwik G. (2011) Global Health Security: Closing the Gaps in Responding to Infectious Disease Emergencies. Global Health Governance.