Being Ready Should Pandemic Influenza Strike

OCCHD is continually building the county’s capacity to respond to large-scale public health emergencies, including the naturally occurring H1N1 pandemic influenza. We are working cooperatively with the Oklahoma State Department of Health, Oklahoma City Emergency Management, the Metropolitan Medical Response System, Medical Emergency Response Center, the Medical Reserve Corps and other local entities.

The severity of the human influenza pandemic cannot be predicted, but modeling studies suggest that the impact of a pandemic on the United States could be substantial. In the absence of any control measures (vaccination or drugs), it has been estimated that in the United States a “medium-level” pandemic could cause 89,000 to 207,000 deaths, 314,000 to 734,000 hospitalizations, 18 to 42 million outpatient visits, and another 20 to 47 million people being sick. Over an expected period of two years, between 15% and 35% of the U.S. population could be affected by an influenza pandemic, and the economic impact could range between $71.3 and $166.5 billion. This effect does not include members of the general population that may have to miss work to care for ill family members, potentially raising the population affected by an influenza pandemic to 55% during the peak weeks of community outbreak (Department of Health and Human Services, Centers for Disease Control and Prevention, Pandemic Flu: Key Facts, January 17, 2006).

Three conditions must be met for a pandemic to begin:

• A new influenza virus subtype must emerge for which there is little or no human immunity. For example, the H5N1 virus (bird flu) is a new virus for humans. It has never circulated widely among people, infecting only around 200 humans, but has killed over half of the people it infects.
• It must infect humans and cause illness.
• It must spread easily and sustainably (continue without interruption) among humans.

An influenza pandemic differs from other public health threats, in that:

• A pandemic will last much longer than most public health emergencies, and may include “waves” of influenza activity separated by months (in 20th century pandemics, a second wave of influenza activity occurred 3 to 12 months after the first wave).
• The numbers of health-care workers and first responders available to work is expected to be reduced. This population will be at high risk of illness through exposure in the community and in health-care settings.
• Resources in many locations could be limited, depending on the severity and spread of an influenza pandemic.
• There will be large surges in the number of people requiring or seeking medical or hospital treatment, which could overwhelm health services.
• High rates of worker absenteeism will interrupt other essential services, such as emergency response, communications, fire and law enforcement, and transportation, even with Continuity of Operations Plans in place.
• Rates of illness are expected to peak fairly rapidly within a given community, because all populations will be fully susceptible to an H5N1-like virus.
• Local social and economic disruptions may be temporary, yet have amplified effects due to today’s closely interrelated and interdependent systems of trade and commerce.
• A second wave of global spread should be anticipated within a year, based on past experience.
• All countries are likely to experience emergency conditions during a pandemic, leaving few opportunities for international assistance, which is typically seen during natural disasters or localized disease outbreaks. Once international spread has begun, governments will likely focus on protecting domestic populations.

For more information regarding pandemic influenza, please visit the following websites:
Centers for Disease Control
Homeland Security
PandemicFlu.gov
Federal Emergency Management Agency
World Health Organization

To contact OCCHD regarding pandemic influenza planning, give us a call at 405-425-4397 or email us at preparedness@occhd.org.