In my 17 years working at the World Health Organization, we experienced numerous infectious disease outbreaks, the most notable being the AIDS pandemic.  The current H1N1 flu reminds us that diseases don't have borders.   With the increasingly global economy and relative ease of travel across and among countries, a new infectious disease emerges almost each year. These epidemics – and in some cases, pandemics -- can have a devastating impact on the economy, security and potential loss of life throughout the world.  These complex global health issues require a multidisciplinary approach to solve and illustrate why we have a Duke Global Health Institute.

An epidemic is a disease outbreak within a defined locale or population.  An epidemic becomes a pandemic when it spreads globally to a larger number of people in multiple countries. An influenza pandemic occurs when a new influenza virus emerges for which there is little or no immunity in the human population, begins to cause serious illness and then spreads easily person-to-person worldwide. 

3. How is the situation today different from some of the other widely known pandemics, most notably the 1918 influenza outbreak?

Historically, there were three flu pandemics in the 20th century, the deadliest of which in 1918.  The 1918 influenza pandemic caused at least 675,000 U.S. deaths and up to 50 million deaths worldwide.  We are in a much better situation today to confront an influenza pandemic. Our health systems are much more advanced, we know much more about how to prevent influenza infection,  and we have medications to treat the flu once it’s detected.  Moreover, except for in Mexico, most of the cases we are seeing are mild.

4. What does it mean when the WHO elevates the threat level?

WHO has a six-phase alert system to provide guidance to nations as to when to active their pandemic preparedness plans.  In general, Phases 1-3 indicate an outbreak of infections predominantly among animals with few human transmissions.  Phase 4 means there is human-to-human transmission detected.  And Phases 5-6 indicate widespread human infections.  The current WHO level is 5.  This is a strong signal that a pandemic is imminent and that it’s time to finalize preparations for it.  At this phasegovernment preparedness plans include steps like ensuring laboratories can test for the disease and health systems can identify and treat cases, track an outbreak and prevent the virus from spreading in hospitals and clinics.

5. When will we know that a pandemic starts?  And when will we know that it is over?

Once WHO announces we’ve moved to Phase 6 we’ll know the pandemic has started. Pandemics often go in waves that can last for months or even years. For this reason it is often difficult to know when a pandemic is truly over.   

6. How concerned should members of the Duke community be about the emerging flu situation?

The Duke community, including students, staff, faculty and patients, should be on alert, as there are still many things we do not know about this H1N1 strain of influenza and it is likely that we will have cases in North Carolina.  Prevention is the best medicine at this stage of the outbreak.

7. Do Duke and other universities face any special issues?

Universities and schools are a special case. We’ve seen the largest number of outbreaks in the U.S. occur in schools. Any time you have a large number of people gathered in a confined space there’s greater risk of human-to-human transmission.

8. Is the situation life threatening?

To put this outbreak into perspective, about 36,000 people in the US die from the seasonal flu each year.  As of May 1, 2009, at 10 a.m., CDC is reporting 109 confirmed cases and one death in the U.S.  Worldwide, a total of 331 cases in 11 countries has been reported, with more than 150 deaths, most of them in or around Mexico City.  We do not know the full extent of this particular strain of the flu, but from the data we have at this point, the H1N1 virus can be life threatening. But it is reassuring that most cases have so far been mild, and that it is possible to prevent most cases through hand washing, covering the nose and mouth when coughing and not going to work or school if you have flu-like symptoms.