Pandemic potential
25 April 2008
As the international association representing the interests of specialized carriers and rigging companies and related industry groups, SC&RA works hard to encourage a worldwide network of interrelated and interdependent systems of trade and commerce. This network, however, also has the potential to amplify the economic and social disruption caused by an influenza pandemic.
Such worldwide outbreaks are rare but recurring events. There were three pandemics in the previous century. They resulted in an estimated 40 to 50 million deaths in 1918, more than two million deaths in 1957, and about a million deaths in 1968.
Epidemiologists worry the world may be on the brink of another pandemic. Most influenza strains do not affect other species. The avian H5N1 strain, however, one of more than 100 identified subtypes affecting birds, began causing alarm in Hong Kong in 1997. The virus resulted in severe respiratory disease in 18 humans, of whom six died. Rapid destruction - within three days - of Hong-Kong's entire poultry population of about 1.5 million birds reduced opportunities for further transition to humans, possibly averting a pandemic.
As at 12 May the World Health Organization (WHO) confirmed that this strain had infected 208 people worldwide, killing 115 in ten nations - Azerbaijan, Cambodia, China, Djibouti, Egypt, Indonesia, Iraq, Thailand, Turkey, and Vietnam. Most of these cases involved people having direct or close contact with H5N1-infected poultry or contaminated surfaces. So far, the virus has not shown the ability to jump easily from birds to humans or spread rapidly and sustainably among humans.
The danger is that H5N1 might ultimately adapt into a strain that is contagious among humans. Because it would be a new virus, the human immune system would have no existing immunity. This increases the likelihood that people who contact pandemic influenza will experience more serious disease than that caused by normal influenza.
Once a fully contagious virus emerges, its global spread is considered inevitable. Closed national borders, quarantined cities, severe travel restrictions, and policies that encourage employees to isolate themselves at home might delay arrival of the virus. But such steps cannot stop it.
The pandemics of the previous century encircled the globe in six to nine months, even when most international travel was by ship. Given the speed and volume of international air travel today, the virus could spread more rapidly, possibly reaching all continents in less than three months. WHO conservatively estimates a bird flu pandemic could cause 2 million to 7.4 million deaths.
The economic impact could also be devastating. Consider that the SARS outbreak in Asia and Canada during 2002-2003 resulted in a $40 billion loss of economic activity globally, with a 45% reduction in air travel to regions affected by the virus.
WHO is coordinating the global response to human cases of H5N1 avian influenza and monitoring the corresponding threat of an influenza pandemic. For more information, go to www.who.int On 3 May the White House released the Implementation Plan For The National Strategy For Pandemic Influenza. The document outlines 300 actions for federal agencies to undertake to address the threat of pandemic influenza.
This plan also addresses the need for a transportation and border management strategy that strikes a balance between efforts to slow the spread of a pandemic with economic and societal consequences of delaying and closing roads and borders. The plan can be viewed at www.whitehouse.gov
