Pandemic flu is a virulent human flu that causes a global outbreak, or pandemic, of serious illness. Because there is little natural immunity, the disease can spread easily from person-to-person. Currently, there is no pandemic flu.
Most of us are familiar with seasonal influenza or the “flu,” a viral infection that, despite annual vaccinations, results in approximately 36,000 deaths in the United States, including 2,000 in Illinois, and 200,000 hospitalizations annually. Intermittently over the centuries, changes in the genetic makeup of influenza virus result in a new strain to which people have never been exposed. These novel strains have the potential to cause a pandemic or worldwide outbreak of influenza, with potentially catastrophic consequences. In Illinois alone, a pandemic of even modest severity could result in thousands of deaths and the sickening of millions, even among those previously healthy. A new strain of influenza virus, H5N1, has been found in birds in Asia and Europe, and has shown it can infect humans. If the avian virus undergoes further change and becomes transmissible between humans, it could very well be the source of a new pandemic. It is impossible to know whether the currently circulating H5N1 strain will cause a human pandemic, but history and science suggest that the world will face one or more pandemics this century.
FREQUENTLY ASKED QUESTIONS
What is pandemic influenza?
A pandemic is a global outbreak of disease that occurs when a novel influenza virus emerges in the human population, it causes serious illness and is spread easily from person-to-person. Currently, there is no pandemic influenza.
What is the difference between a pandemic and a seasonal outbreak of the flu?
A pandemic is caused by a new influenza virus that most people have not been exposed to, so there is little or no pre-existing immunity.
Seasonal flu is a contagious respiratory illness caused by influenza viruses that are similar to previous years. Some people may have built up immunity and there also is a vaccine for each year’s flu season. It can cause mild to severe illness and is responsible for about 36,000 deaths each year in the United States, including about 1,800 deaths in Illinois.
When is the next pandemic expected?
Pandemics have occurred intermittently over centuries – 10 in the last 300 years, including three in the last century, 1918, 1957 and1968. No one can predict the timing or severity of the next pandemic, but many scientists believe it is only a matter of time before the next one occurs. History and science suggest we will face one or more pandemics this century.
Why is there concern about avian influenza?
Currently, avian or “bird” flu is just that – a strain (H5N1) of influenza that is infecting and killing birds in Asia, Africa and parts of Europe. The H5N1 virus has been transmitted from birds to mammals and, in some limited circumstances, to humans who have come in close contact with the sick birds. Scientists are concerned that the bird strain could mutate or change and become transmissible between humans, which could then trigger a pandemic.
What is Illinois doing to address the threat of pandemic flu?
The Illinois Department of Public Health is charged with leading state government and its public health and health care partners in the event of a catastrophic infectious disease outbreak, such as an influenza pandemic. The Department developed a pandemic influenza response plan in 2001 that is continually being updated to stop, slow or otherwise limit the spread of a pandemic.
Recently, the Department joined the Office of the Governor and the Illinois Emergency Management Agency to develop an emergency plan for responding to an influenza pandemic. The state, as well as local health departments and other public health partners, frequently exercise all or parts of the plan to test the state’s preparedness. In the event a vaccine against a pandemic flu is available, the Department has developed plans for mass immunizations. And the state has reviewed its laws and regulations pertaining to its authority to impose isolation and quarantine orders, and restrict public gatherings, such as at sporting events and concerts.
What is the federal government doing?
- Supporting federal, state and local health agencies’ efforts to prepare for and respond to a pandemic flu outbreak;
- Working with the World Health Organization (WHO) and other nations to help detect and contain outbreaks;
- Developing a national stockpile of antiviral drugs to help treat and control the spread of disease;
- Supporting the manufacture and testing of possible vaccines, including finding more reliable and quicker ways to make large quantities of vaccine;
- Working with federal agencies to prepare and to encourage communities, businesses and organizations to plan for a pandemic flu outbreak.
What risks do Illinoisans face in a flu pandemic?
The spread of a new strain of the flu to which people have never been exposed has the potential to sweep around the world in as little as three months, causing millions of illnesses and death. The impact of such an event could have a devastating effect on the health and well-being of the public. In, Illinois, it has been projected that a moderate pandemic, over the course of 12 weeks, would cause:
- 8,700 deaths
- 30,000 hospitalizations
- 1.8 million outpatient visits
- 2 million becoming ill
A pandemic is likely to come in waves, each lasting months, and pass through communities of all size across the world, nation and the state. It ultimately could threaten all critical infrastructure by removing essential personnel from the workplace for weeks or months.
Does the annual flu vaccine protect people against pandemic influenza?
No. Influenza vaccines are designed to protect against a specific virus, so a pandemic vaccine cannot be produced until a new pandemic influenza virus emerges and is identified. Even after a pandemic influenza virus has been identified, it could take six months to develop, test and produce vaccine, and then only limited amounts would be available at first. Research is underway to explore how to make vaccines more quickly.
How will vaccine be distributed if a pandemic breaks out?
Illinois and local health departments have developed plans to rapidly distribute what vaccine may be available. These plans build on experience gained on other emergencies. The state would work with the federal government and other partners to make recommendations to guide the early use of vaccine.
Vaccine makers already have a system in place to distribute vaccine. Tens of millions of doses of seasonal influenza vaccine are shipped every year, and during shortages, vaccine makers have responded to urgent situations.
Fairness in vaccine distribution and use during a pandemic are important. Protecting people at high risk and safeguarding essential day-to-day services are important considerations in distributing the limited supply of vaccine that will be available.
What age groups are most likely to be affected during an influenza pandemic?
Although scientists cannot predict the specific consequences of an influenza pandemic, it is likely that many age groups would be seriously affected. Factors to consider include:
- Few, if any, people would have immunity to the virus.
- The virus could spread rapidly.
- An influenza pandemic could temporarily disrupt activities important to overall public health, the economy and essential community services.
What is the difference between a vaccine and an antiviral?
Vaccines are usually given as a preventive measure. Currently available viral vaccines are usually made from either killed virus or weakened versions of the live virus or pieces of the virus that stimulate an immune response to the virus. When immunized, the body is then poised to fight or prevent infection more effectively.
Antivirals are drugs that may be given to help prevent viral infections or to treat people who have been infected by a virus. When given to treat people who have been infected, antiviral medications may help limit the impact of some symptoms and reduce the potential for serious complications, especially for people in high-risk groups.
How would antivirals be used?
Antivirals may help prevent infection in people at risk and lessen the impact of symptoms in those infected with influenza. It is unlikely that they would substantially modify the course or effectively contain the spread of an influenza pandemic.
A number of antiviral medications are approved by the U.S. Food and Drug Administration to treat and, sometimes, prevent flu. At this time, Tamiflu and Relenza are the most likely antivirals to be used in a pandemic. There are efforts underway to find new drugs and to increase the supply of antivirals. If everyone follows the recommended uses of antivirals, there will be more available for those who need it most.
What other prevention strategies will be available to protect people?
In the event of a pandemic, certain public health measures may be important to help contain or limit the spread of infection as effectively as possible. The actions could include:
- Treating sick and exposed persons with antivirals,
- isolating sick people in hospitals, homes or other facilities,
- identifying and quarantining exposed people,
- canceling public events, and
- restricting travel.
In addition, people should protect themselves by:
- Getting seasonal flu shots,
- washing hands frequently with soap and warm water,
- covering your nose and mouth with a tissue when coughing or sneezing,
- avoiding touching eyes, nose or mouth,
- staying away from people who are sick, and staying home when you are sick.