Swine Flu: Now Full-Scale Pandemic
'The move to Phase 6, the highest level in WHO's graduated scale of pandemic alerts, has been expected for weeks.'

Ruth Karron
Director, Center for Immunization Research and Vaccine Initiative ,Johns Hopkins Bloomberg School of Public Health
Thursday, June 11, 2009 3:00 PM

The World Health Organization today declared the global outbreak of the H1N1 influenza virus to be in Phase 6 -- a full-scale pandemic. The announcement essentially warns WHO's 194 member nations to expect the arrival of the new flu strain, which is likely to infect up to one-third of the population in the first wave and return in later waves over the next several years.

What does this mean for the world and the U.S.? Who is at risk now? Ruth Karron, director of the Center for Immunization Research and Vaccine Initiative at Johns Hopkins Bloomberg School of Public Health, was online Thursday, June 11, at 3 p.m. ET to discuss today's announcement.


Ruth Karron: Hi, This is Ruth Karron from Johns Hopkins Bloomberg School of Public Health, here to answer questions about the WHO's declaration today that we are at a pandemic level for novel H1N1 influenza.


Kansas City, Mo.: What steps should we take to ensure the safety of our families and communities?

Ruth Karron: There will be a number of steps that we can take as individuals and as communities to help protect ourselves. Some of these are measures that we as individuals can put in place right now if we have not already done so. These include staying home when you are ill, practicing good hand and respiratory hygiene, and keeping yourself informed. In the coming weeks and months, there will be other measures (such as the use of vaccines or antivirals) that may be employed at the recommendation of federal or local public health officials.


Washington, D.C.: Does this new level apply to conditions in the U.S. or just outside of the country? Can you please explain what the higher level means to specific locations?

Ruth Karron: This is a global increase-- by definition, pandemic means that the virus has had sustained person-to-person spread on more than one continent.


Washington, D.C.: Will this cause some countries to automatically adjust their travel policies? Should I delay any international travel plans?

Ruth Karron: At this point, H1N1 influenza is widespread. For that reason, WHO does not recommend any restriction on travel or the closing of any borders. Despite this recommendation, it remains to be seen whether individual countries will change their travel policies.


Over 52: As a child, I had the flu that was going around in Fall 1957. Seriously, how much immunity could I still have after 52 years?

Ruth Karron: While it's difficult to know how much immunity you have as an individual, the CDC has published studies to show that some individuals born before 1957 appear to have antibodies to this novel H1N1 virus. So, the possibility exists that older individuals in the community may be less vulnerable than younger individuals.


Washington, D.C.: So it's pandemic for everywhere?

Ruth Karron: Yes, this is a global pandemic.


Washington, D.C.: Will the fall vaccine be effect on this H1N1 strain and should public places be avoided?

Ruth Karron: Manufacturers are producing both seasonal flu vaccine and the H1N1 vaccine. We will hear more in the coming months about vaccination strategies in the US.

At this point, there are no recommendations to avoid public places.


Ffx: What are the symptoms of Swine Flu?

Ruth Karron: The symptoms of swine flu may be very similar to seasonal flu: sore throat, cough, and fever. It appears that GI symptoms (vomiting or diarrhea) occur somewhat more frequently with this flu than with typical seasonal flu.


On the front lines: I am a nurse practitioner in a children's hospital and my biggest worry is inadvertently infecting my family if I come in contact with a patient with H1N1. I practice as effective infection control as I can but I wonder how I'll feel the 1st time I need to walk into a room with a confirmed case who is intubated? Those who faced SARS and didn't flinch are heroes.

Ruth Karron: You should be discussing your concerns with your hospital's infection control personnel. Hospitals have developed policies to respond to pandemic influenza, which may include the use of additional protective gear if it is warranted.


Alexandria, Va.: Have there been any reported deaths from H1N1 that did not have any other health related issues?

Also, I think the WHO as well as the media have done a disservice by not explaining what constitutes a pandemic. People get to the PAN part and then remove the DEM to leave PANIC, which then spreads false information around.

Ruth Karron: In the WHO briefing today, Dr. Keiji Fukuda indicated that there have been some deaths in individuals without underlying conditions.

Although there is always room for improvement, I think that the WHO has tried to explain that the term "pandemic" refers to the degree of spread (person to person transmission on more than one continent)rather than the severity of disease. They characterize the current pandemic as being of moderate severity. I agree with you that this not a time to panic.


Washington, D.C.: As a professional, with knowledge of the disease, what was your response to this news today?

Ruth Karron: This announcement did not come as a surprise--it is an acknowledgement of the epidemiology that has been observed and reported. It reminds us that we need to continue to prepare and respond as needed.


Arlington, Va.: Have other diseases reached this scale on the WHO's levels?

Ruth Karron: Influenza is the only disease that has been classified in this way. This is the fist influenza pandemic of the 21st century. The last influenza pandemic occurred in 1968.


Ruth Karron: I'll be signing off now--thanks for all of your questions.

Ruth Karron


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