Study explains importance of identifying global pandemic risk factors to predict spread of diseases

EcoHealth AllianceOct 7 2010

A recent peer-reviewed study, led by EcoHealth Alliance's Dr. Parviez Hosseini, identifies key risk factors for the global spread of diseases, and best practices to predict and prevent the spread of pandemic diseases

A recent study led by Dr. Parviez Hosseini, a senior research fellow from EcoHealth Alliance (formerly Wildlife Trust), explains the importance of identifying global pandemic risk factors as early as possible, in order to predict the spread of diseases like H1N1 "swine" flu and SARS. "Predictive Power of Air Travel and Socio-Economic data for Early Pandemic Spread," recently published in the scientific publication PLoS ONE, examines the interplay among travel, trade, and national healthcare resources in predicting the emergence and spread of H1N1 and other viruses.

The report points to the need for improved surveillance of diseases in traded livestock and rapid deployment of control measures in those countries first affected – especially countries in the predicted path of the disease and those with fewer healthcare resources. "The most benefit accrues when higher-income countries provide additional resources to lower-income countries, particularly those that have high-volume air traffic," said Dr. Hosseini. "International authorities should earmark more aid for the poorest countries where the risk of emerging infectious diseases is highest, in order to detect infections as early as possible, and to reduce the human and economic disaster of global pandemics."

2009 H1N1 Outbreak Lessons Learned

By May 2009, two weeks after cases of the A/H1N1 strain was first reported, the disease had already spread to 24 countries, 40 U.S. states, and nine Canadian provinces. The rapid spread of this disease was due in large part to consumer air travel exacerbated by slow reporting in countries with the fewest healthcare resources. "We might one day be able to predict the emergence of viruses and develop vaccines more quickly; however, in order to do so, we first need to have greater surveillance in countries with the fewest healthcare resources," Hosseini said.

Last year's strain of H1N1 was relatively mild; however, if a more dangerous strain like the H5N1 "avian flu" subtype were to spread similarly, the outcome would be catastrophic in terms of human suffering and economic damage. Were this to occur, the economic cost has been estimated between $71 billion and $167 billion. "The measures we propose are likely to have economic benefits that far outweigh their costs," according to Hosseini.

Among the key conclusions and strategies recommended in the report were the following:

1. Expanded surveillance for diseases in livestock populations – Only through surveillance can scientists predict the emergence of diseases, and develop vaccines in advance of their spread; however, even dramatic reductions in the international live animal trade may not prevent the exposure of local livestock to new types of viruses from distant locations.
2. Leverage major airport hubs to halt the spread of disease – Rather than rely solely on travel restrictions, airports serving as major transportation hubs could also become venues both for disease surveillance, as well as serve double duty as facilities to train people and stockpile medicines in preparation for pandemics.
3. Provide aid to countries with the lowest healthcare resources – Healthcare spending plays a critical role in determining a country's ability to detect, confirm, and report cases in the early stages; it is in the best interests of intergovernmental and other aid agencies to provide subsidies for outbreak response to nations with high air-travel connectivity and low healthcare resources.
4. Early targeting – Efforts to target diseases are more effective when they are set up in advance of a pandemic; and these efforts should be positioned to target emerging-disease hot spots.